The present disclosure generally relates to light emitting diode, and more particularly, to a micro light emitting diode (LED), a micro-LED array panel, and a manufacturing method thereof.
Inorganic micro pixel light emitting diodes, also referred to as micro light emitting diodes, micro-LEDs or μ-LEDs, are of increasing importance because of their use in various applications including self-emissive micro-displays, visible light communications, and optogenetics. The micro-LEDs exhibit higher output performance than conventional LEDs due to better strain relaxation, improved light extraction efficiency, and uniform current spreading. The micro-LEDs also exhibit improved thermal effects, fast response rate, larger work temperature range, higher resolution, color gamut and contrast, and lower power consumption, and can be operated at higher current density compared with conventional LEDs.
The inorganic micro-LEDs are conventionally III-V group epitaxial layers formed as multiple mesas. A space is formed between the adjacent micro-LEDs in the conventional micro-LEDs structures to avoid carriers in the epitaxial layer spreading from one mesa to an adjacent mesa. However, the space which is formed between the adjacent micro-LEDs can reduce an active light emitting area and decrease light extraction efficiency. If there is no space between the adjacent micro-LEDs, the active light emitting area would be increased and the carriers in the epitaxial layer would spread laterally to the adjacent mesa, which reduces the light emitting efficiency of the micro-LED. Furthermore, if there is no space formed between the adjacent mesas, cross talk will be produced between the adjacent micro-LEDs, which would interfere with LEDs operation.
However, smaller micro-LEDs with higher current densities will experience red-shift, lower maximum efficiency, and inhomogeneous emission at high current density, which has been attributed to fabrication process damage that results in degraded electrical injection. In addition, the peak external quantum efficiencies (EQEs) and internal quantum efficiency (IQE) are largely decreased with decreasing chip size. The decreased EQE appears due to nonradiative recombination caused by etching damage and the decreased IQE is attributed to poor current injection and electron leakage current of micro-LEDs.
The above discussion is only provided to assist in understanding the technical problem overcome by the present disclosure, and does not constitute an admission that the above is prior art.
Embodiments of the present disclosure provide a micro-LED. The micro-LED includes a first type semiconductor layer; and a light emitting layer formed on the first type semiconductor layer; a first type cap layer formed at a bottom surface of the light emitting layer and between the first type semiconductor layer and the light emitting layer; wherein the first type semiconductor layer includes a mesa structure, a trench, and a ion implantation fence separated from the mesa structure, the trench extending up through the first type semiconductor layer and extending up into at least part of the first type cap layer; and the ion implantation fence is formed around the trench and the trench is formed around the mesa structure; wherein an electrical resistance of the ion implantation fence is higher than an electrical resistance of the mesa structure.
Embodiments of the present disclosure provide a method for manufacturing a micro-LED. The method includes providing an epitaxial structure, wherein the epitaxial structure includes a first type semiconductor layer, a first type cap layer, a light emitting layer, a second type cap layer, and a second type semiconductor layer sequentially from top to bottom; patterning the first type semiconductor layer to form a mesa structure, a trench, and a fence; depositing a bottom contact on the mesa structure; and performing an ion implantation process into the fence to form an ion implantation fence.
Embodiments of the present disclosure provide micro-LED array panel. The micro-LED array panel includes a plurality of the above-described micro-LEDs.
Embodiments and various aspects of the present disclosure are illustrated in the following detailed description and the accompanying figures. Various features shown in the figures are not drawn to scale.
Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings in which the same numbers in different drawings represent the same or similar elements unless otherwise represented. The implementations set forth in the following description of exemplary embodiments do not represent all implementations consistent with the invention. Instead, they are merely examples of apparatuses and methods consistent with aspects related to the invention as recited in the appended claims. Particular aspects of the present disclosure are described in greater detail below. The terms and definitions provided herein control, if in conflict with terms and/or definitions incorporated by reference.
The present disclosure provides a micro-LED which can avoid nonradiative recombination at sidewalls of a mesa according to a structure of a semiconductor layer and continuously formed light emitting layer. Furthermore, compared with conventional micro-LEDs, a space between adjacent mesas can be decreased largely due to an ion implantation fence. Therefore, the integration level of the micro-LEDs in a chip is increased and the active light emitting efficiency is improved. Furthermore, the micro-LED provided by the present disclosure can also increase the active light emitting area and improve the image quality.
Referring to
A conductive type of the first type semiconductor layer 110 is different from a conductive type of the second type semiconductor layer 120. In some embodiments, the conductive type of the first type semiconductor layer 110 is P type and the conductive type of the second type semiconductor layer 120 is N type. In some embodiments, the conductive type of the second type semiconductor layer 120 is P type and the conductive type of the first type semiconductor layer 110 is N type. For example, a material of the first type semiconductor layer 110 can be selected from one or more of p-GaAs, p-GaP, p-AlInP, p-GaN, p-InGaN, or p-AlGaN. The material of the second type semiconductor layer 120 can be selected from one or more of n-GaAs, n-AlInP, n-GaInP, n-AlGaAs, n-AlGaInP, n-GaN, n-InGaN, or n-AlGaN. A conductive type of the first type cap layer 114 is the same as the conductive type of the first type semiconductor layer 110 and a conductive type of the second type cap layer 124 is the same as the second type semiconductor layer 120.
The first type semiconductor layer 110 includes a mesa structure 111, a trench 112 and an ion implantation fence 113. The ion implantation fence 113 is separated from the mesa structure 111 by the trench 112. The trench 112 and the ion implantation fence 113 are annular around the mesa structure 111.
The ion implantation fence 113 includes a light absorption material for absorbing light from the mesa structure 111. A conductive type of the light absorption material is the same as the conductive type of the first type semiconductor layer 110. Preferably, the light absorption material is selected from one or more of p-GaAs, p-GaP, p-AlInP, p-GaN, p-InGaN, or p-AlGaN. Additionally, the ion implantation fence 113 is formed at least by implanting ions into a fence formed from the first type semiconductor layer 110. Preferably, the ion type implanted into the fence is selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
Furthermore, the width of the ion implantation fence 113 is not greater than 50% of the diameter of the mesa structure 111. In some embodiments, the width of the ion implantation fence 113 is not greater than 10% of the diameter of the mesa structure 111. Preferably, the width of the ion implantation fence 113 is not greater than 200 nm, the diameter of the mesa structure 111 is not greater than 2500 nm, and the thickness of the first type semiconductor layer 110 is not greater than 300 nm.
In some embodiments, the width of the trench 112 is not greater than 50% of the diameter of the mesa structure 111. In some embodiments, the width of the trench 112 is not greater than 10% of the diameter of the mesa structure 111. Preferably, the width of the first trench 112 is not greater than 200 nm.
In some embodiments, the top surface of the ion implantation fence 113 is lower than or aligned with the top surface of the first type semiconductor layer 110. Therefore, the ion implantation fence 113 can contact the first type cap layer 114 but cannot contact the light emitting layer 130. The top surface of the ion implantation fence 113 can be formed at any position within the first type semiconductor layer 110. As shown in
In some embodiments, the trench 112 extends up through the first type semiconductor layer 110 and the first type cap layer 114 and reaches the light emitting layer 130. In some embodiments, referring to
Referring to
Additionally, the bottom surface of the ion implantation fence 113 can be formed at any position. Preferably, the bottom surface of the ion implantation fence 113 is aligned with the bottom surface of the first type semiconductor layer 110. Referring to
In some embodiments, as shown in
In this embodiment, an integrated circuit (IC) backplane 190 is formed under the first type semiconductor layer 110 and is electrically connected with the first type semiconductor layer 110 via a connection structure 150. As shown in
The micro-LED further includes a bottom contact 160. The bottom contact 160 is formed at the bottom of the first type semiconductor layer 110. An upper surface of the connection structure 150 is connected with the bottom contact 160 and a bottom surface of the connection structure 150 is connected with the IC backplane 190.
Referring to
Referring to
In step 502: referring to
The step 502 may further include: etching the first type semiconductor layer 610, the first type cap layer 614, and the light emitting layer 630 in sequence, and stopping the etching on the second type cap layer 624. As shown in
In some embodiments, the step 502 may include: etching the first type semiconductor layer, the first type cap layer and the light emitting layer in sequence, and stopping the etching in the light emitting layer. For example, referring back to
In some embodiments, the step 502 may include: etching the first type semiconductor layer, the first type cap layer, the light emitting layer, the second type cap layer, and the second type semiconductor layer in sequence, and stopping the etching in the second type semiconductor layer. For example, referring back to,
Referring back to
In step 503: referring to
Before the bottom contact 660 deposited, a first protective mask (not shown) is used to protect an area where the bottom contact 660 will not be formed. Then, the material of the bottom contact 660 is deposited on the first protective mask and on the first type semiconductor layer 610 by a conventional vapor deposition process, such as a physical vapor deposition process or a chemical vapor deposition process. After the deposition process, the first protective mask is removed from the first type semiconductor layer 610 and the material on the first protective mask is also removed with the first protective mask to form the bottom contact 660 on the mesa structure 611.
In step 504: referring to
In combination with
In step 505: referring to
As shown in
In step 506: referring to
In step 507: referring to
In step 508: referring to
In step 509: referring to
In step 510: referring to
A micro-LED array panel is further provided by some embodiments of the present disclosure. The micro-LED array panel includes a plurality of micro-LEDs as described above and shown in
A conductive type of the first type semiconductor layer 710 is different from a conductive type of the second type semiconductor layer 720. For example, in some embodiments, the conductive type of the first type semiconductor layer 710 is P type, and the conductive type of the second type semiconductor layer 720 is N type. In some embodiments, the conductive type of the second type semiconductor layer 720 is P type, and the conductive type of the first type semiconductor layer 710 is N type. The thickness of the first type semiconductor layer 710 is greater than the thickness of the second type semiconductor layer 720. In some embodiments, the material of the first type semiconductor layer 710 is selected from one or more of p-GaAs, p-GaP, p-AlInP, p-GaN, p-InGaN, or p-AlGaN. The material of the second type semiconductor layer 720 is selected from one or more of n-GaAs, n-AlInP, n-GaInP, n-AlGaAs, n-AlGaInP, n-GaN, n-InGaN, or n-AlGaN. A conductive type of the first type cap layer 714 is the same as the conductive type of the first type semiconductor layer 710 and a conductive type of the second type cap layer 724 is the same as the second type semiconductor layer 720.
The first type semiconductor layer 710 includes multiple mesa structures 711, multiple trenches 712, and multiple ion implantation fences 713 separated from the mesa structures 711 by the trenches 712. The top surface of the ion implantation fence 713 is aligned with or lower than the top surface of the first type semiconductor layer 710. Thus, the ion implantation fence 713 cannot reach the light emitting layer 730. The top of the ion implantation fence 713 can be formed at any position. Additionally, the bottom surface of the ion implantation fence 713 can be formed at any position. The relationship of the top surface of the ion implantation fence 713, the top surface of the first type semiconductor layer 710, and the top surface of the trench 712 can be seen in the micro-LED shown in
In some embodiments, the space between the adjacent sidewalls of the adjacent ones of the mesa structure 711 can be adjusted. For example, in some embodiments, the space between the adjacent sidewalls of the mesa structures 711 is not greater than 50% of the diameter of the mesa structure 711. In some embodiments, the space between the adjacent sidewalls of the mesa structures 711 is not greater than 30% of the diameter of the mesa structure 711. Preferably, the space between the adjacent sidewalls of the mesa structure 711 is not greater than 600 nm. Additionally, in some embodiments, the width of the ion implantation fence 713 can be adjusted. For example, the width of the ion implantation fence 713 can be not greater than 50% of the diameter of the mesa structure 711. In some embodiments, the width of the ion implantation fence 713 can be not greater than 10% of the diameter of the mesa structure 711. Preferably, in the micro-LED array panel, the width of the ion implantation fence 713 is not greater than 200 nm.
In this embodiment, the micro-LED array panel further includes a top contact 980 and a top conductive layer 970. The top contact 980 is formed on the top of a second type semiconductor layer 920. The top conductive layer 970 is formed on the top of the second type semiconductor layer 920 and the top contact 980. A conductive type of the top contact 980 is the same as a conductive type of the second type semiconductor layer 920. For example, in some embodiments, the conductive type of the second type semiconductor layer 920 is N type and the conductive type of the top contact 980 is N type. In some embodiments, the conductive type of the second type semiconductor layer 920 is P type and the conductive type of the top contact 980 is P type. The top contact 980 is made of metal or metal alloy, such as, AuGe, AuGeNi, etc. The top contact 980 is used for forming ohmic contact between the top conductive layer 970 and the second type semiconductor layer 920, to optimize the electrical properties of the micro-LEDs. The diameter of the top contact 980 is about 20˜50 nm and the thickness of the top contact 980 is about 10˜20 nm.
The micro-LED array panel can be manufactured by the method 500 as shown in
The second type semiconductor layer 1020 includes a mesa structure 1021, a trench 1022, and an ion implantation fence 1023 separated from the mesa structure 1021. The bottom surface of the ion implantation fence 1023 is aligned with or higher than the bottom surface of the second type semiconductor layer 1020. Thus, the ion implantation fence 1023 can reach the second type cap layer 1024 but cannot reach the light emitting layer 1030. The bottom surface of the ion implantation fence 1023 can be formed at any position. Furthermore, the ion implantation fence 1023 is formed around the trench 1022 and the trench 1022 is formed around the mesa structure 1021. The electrical resistance of the ion implantation fence 1023 is higher than the electrical resistance of the mesa structure 1021.
The ion implantation fence 1023 includes a light absorption material for absorbing light from the mesa structure 1021. A conductive type of the light absorption material is the same as the conductive type of the second type semiconductor layer 1020. Preferably, the light absorption material is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN. Additionally, the ion implantation fence 1023 is formed at least by implanting ions into the second type semiconductor layer 1020. Preferably, the ion type implanted into the second type semiconductor layer 1020 is selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
Furthermore, the width of the ion implantation fence 1023 can be adjusted. For example, in some embodiments, the width of the ion implantation fence 1023 is not greater than 50% of the diameter of the mesa structure 1021. In some embodiments, the width of the ion implantation fence 1023 is not greater than 10% of the diameter of the mesa structure 1021. Preferably, the width of the ion implantation fence 1023 is not greater than 200 nm. The diameter of the mesa structure 1021 is not greater than 2500 nm. The thickness of the second type semiconductor layer 1020 is not greater than 100 nm.
In some embodiments, the width of the trench 1022 is not greater than 50% of the diameter of the mesa structure 1021. In some embodiments, the width of the trench 1022 is not greater than 10% of the diameter of the mesa structure 1021. Preferably, the width of the trench 1022 is not greater than 200 nm.
There is no limitation on the depth of the trench 1022. In some embodiments, the trench 1022 can extend down through the second type semiconductor layer 1020 and enter into the interior of the second type cap layer 1024. In some embodiments, the trench 1022 can extend down through the second type semiconductor layer 1020 and the second type cap layer 1024, and reach the light emitting layer 1030. In some embodiments, the trench 1022 can extend down through the second type semiconductor layer 1020 and the second type cap layer 1024, and extend into the interior of the light emitting layer 1030. In some embodiments, the trench 1022 can extend down through the second type semiconductor layer 1020, the second type cap layer 1024, and the light emitting layer 1030. Furthermore, in some embodiments, the trench 1022 can extend down through the second type semiconductor layer 1020, the second type cap layer 1024, and the light emitting layer 1030, and extend down into the interior of the first type cap layer 1014. Furthermore, in some embodiments, the trench 1022 can extend down through the second type semiconductor layer 1020, the second type cap layer 1024, the light emitting layer 1030, and the first type cap layer 1014, and extend down into the interior of the first type semiconductor layer 1010.
In some embodiments, as shown in
In some embodiments, as shown in
Additionally, in some embodiments, the top surface of the ion implantation fence 1023 can be formed at any position. In some embodiments, as shown in
In some embodiments, as show in
Additionally, in some embodiments, the micro-LED further includes a top contact 1080 and a top conductive layer 1070. The top contact 1080 is formed on the top of the second type semiconductor layer 1020. The top conductive layer 1070 is formed on the top surface of the second type semiconductor layer 1020 and the top surface of the top contact 1080, and covers the sidewalls of the second trench 1022. Preferably, a dielectric layer 1071 is formed on a sidewall and bottom surface of the trench 1022. A conductive type of the top contact 1080 is the same as a conductive type of the second type semiconductor layer 1020. For example, the conductive type of the second type semiconductor layer 1020 is N type and the conductive type of the top contact 1080 is N type. The top contact 1080 is made of metal or metal alloy, such as, AuGe, AuGeNi, etc. The top contact 1080 is used for forming an ohmic contact between the top conductive layer 1070 and the second type semiconductor layer 1020, to optimize the electrical properties of the micro-LED. The diameter of the top contact 1080 is about 20˜50 nm and the thickness of the top contact 1080 is about 10˜20 nm.
Referring to
Referring to
Preferably, before turning upside down the epitaxial structure, a bottom contact layer 1560 used as the bottom contact is deposited on the top surface of the first type semiconductor layer 1510. Then, a metal bonding layer which is used as a connection structure 1550 is deposited on the top surface of the bottom contact layer 1560.
In step 1402: referring to
In step 1403: referring to
In some embodiments, the step 1403 further includes: etching the second type semiconductor layer and the second type cap layer, and stopping the etching on the top surface of the light emitting layer 1030, to avoid the light emitting layer being etched in the patterning process. As shown in
In some embodiments, the step 1403 further includes: etching the second type semiconductor layer and the light emitting layer in sequence, and stopping the etching in the light emitting layer 1030. Referring back to
In some embodiments, the step 1403 further includes: etching the second type semiconductor layer, the light emitting layer, and the first type semiconductor layer in sequence, and stopping the etching in the first type semiconductor layer. Referring back to
The second type semiconductor layer 1520 is etched by a conventional dry etching process, such as a plasma etching process, which can be understood be those skilled in the field.
In step 1404: referring to
In step 1405: referring to
In step 1406: referring to
Before forming the top conductive layer 1570, a dielectric layer 1571 is formed on the sidewalls and the bottom surface of the trench 1522. As shown in
Referring back to
A micro-LED array panel is further provided according to some embodiments of the present disclosure. The micro-LED array panel includes a plurality of micro-LEDs as described above shown in
The second type semiconductor layer 1620 includes multiple mesa structures 1621, multiple trenches 1622, and multiple ion implantation fences 1623 separated from the mesa structures 1621 by the trenches 1622. The bottom surface of the ion implantation fence 1623 is not lower than the bottom surface of the second type semiconductor layer 1620.
Variations in the relationship of the bottom surface of the ion implantation fence 1623, and the bottom surface of the second type semiconductor layer 1620, and the bottom of the trench 1622 generally correspond to those shown for the micro-LED in
In some embodiments, the space between the adjacent sidewalls of adjacent ones of the mesa structures 1621 can be adjusted. For example, in some embodiments, the space between the adjacent sidewalls of the mesa structures 1621 is not greater than 50% of the diameter of the mesa structure 1621. In some embodiments, the space between the adjacent sidewalls of the mesa structures 1621 is not greater than 30% of the diameter of the mesa structure 1621. Preferably, the space between the adjacent sidewalls of the mesa structures 1621 is not greater than 600 nm. Additionally, in some embodiments, the width of the ion implantation fence 1623 can be adjusted. For example, the width of the ion implantation fence 1623 can be not greater than 50% of the diameter of the mesa structure 1621. In some embodiments, the width of the ion implantation fence 1623 can be not greater than 10% of the diameter of the mesa structure 1621. Preferably, in the micro-LED array panel, the width of the ion implantation fence 1623 is not greater than 200 nm.
A bottom contact 1660 is formed at the bottom of the first type semiconductor layer 1610. A connection structure 1650 is a metal bonding layer for bonding the micro-LED with an IC backplane 1690. The detail of the bottom contact 1660, the connection structure 1650 and the IC backplane 1690 can be found as referring to the above described micro-LED in
Furthermore, referring back to
Additionally, further details regarding the features of the micro-LED and the ion implantation fence in the micro-LED array panel can be understood by also referring to the micro-LEDs as shown in
The micro-LED array panel shown in
The first type semiconductor layer 1910 includes a first mesa structure 1911, a first trench 1912, and a first ion implantation fence 1913 separated from the first mesa structure 1911. The second type semiconductor layer 1920 includes a second mesa structure 1921, a second trench 1922, and a second ion implantation fence 1923 separated from the second mesa structure 1921.
Combined with
Combined with
Referring back to
In some embodiments, the center of the first mesa structure 1911 is aligned with the center of the second mesa structure 1921, the center of the first trench 1912 is aligned with the center of the second trench 1922, and the center of the first ion implantation fence 1913 is aligned with the center of the second ion implantation fence 1923.
The relationship of the top surface of the first ion implantation fence 1913, the top surface of the first trench 1912, and the top surface of the first type semiconductor layer 1910 is the same as that of the variants of the micro-LED in Embodiment 1 shown in
The relationship of the bottom of the second ion implantation fence 1923, the bottom of the second trench 1922, and the bottom of the second type semiconductor layer 1920 is the same as that of the variants of the micro-LED in embodiment 2 shown in
The micro-LED further includes a top contact 2080 and a top conductive layer 2070. The top contact 2080 is formed on the top of a second type semiconductor layer 2020. The top conductive layer 2070 is formed on the top of the second type semiconductor layer 2020 and the top contact 2080 and covers the sidewalls and bottom of the second trench 2022. Further details regarding the top contact 2080 and the top conductive layer 2070 can be found by referring to the description for Embodiment 2, which will not be further described here.
Additionally, further details regarding the micro-LED shown in
In Process I: the first type semiconductor layer is patterned, and then ions are implanted into the first type semiconductor layer to form a first ion implantation fence.
In Process II: the second type semiconductor layer is patterned, and then ions are implanted into the second type semiconductor layer to form a second ion implantation fence.
Referring to
For Process I, the steps 2101-2109 are similar to the steps 501-509 of method 500 as shown in
In step 2103: referring to
In step 2104: referring to
In step 2105: referring to
The bottom isolation layer can be filled into the first trench. In some embodiments, the bottom isolation layer can be formed on the sidewalls of the first mesa structure, the first ion implantation fence, the first type semiconductor layer, the first type cap layer, the light emitting layer and the second type semiconductor layer, the second mesa structure, the second type cap layer, and the second type ion implantation fence in the first trench, which depends on a depth of the first trench.
In step 2106: referring to
In step 2107: referring to
In step 2108: referring to
In step 2109: referring to
In step 2111: referring to
In step 2112: referring to
In step 2113: referring to
In some embodiments, as shown to
The bottom isolation layer 2340 is formed on the sidewalls and the top of the first trench 2312, and the dielectric layer 2371 is formed on the sidewalls and the bottom of the second trench 2322. The thickness of the bottom isolation layer extending into the first trench 2312 depends on a position of the bottom of the second trench 2322 and a position of the top of the first trench 2312. The thickness of the dielectric layer 2371 extending into the second trench 2322 depends on a position of the bottom of the second trench 2322 and a position of the top of the first trench 2312.
A top contact and a bottom contact can be formed on the micro-LED according to some embodiments of the present disclosure, which will not be further described here.
Further details of the Process I can be found by reference to the description of steps 501-509 for the Embodiment 1. Further details of the Process II can be found by reference to the description of steps 1403-1406 for the Embodiment 2, which will not be further described here.
A micro-LED array panel is further provided according to some embodiments of the present disclosure. The micro-LED array panel includes a plurality of micro-LEDs as described above and shown in
The first type semiconductor layer 2410 includes multiple first mesa structures 2411, multiple first trenches 2412, and multiple first ion implantation fences 2413 separated from the first mesa structures via the first trenches 2412. The top surface of the first ion implantation fence 2413 is lower than the top surface of the first type semiconductor layer 2410. Referring back to
The second type semiconductor layer 2420 includes multiple second mesa structures 2421, multiple second trenches 2422, and multiple second ion implantation fences 2423 separated from the second mesa structures 2421 via the second trenches 2422. The bottom surface of the second ion implantation fence 2423 is higher than the bottom surface of the second type semiconductor layer 2420. A top view of the micro-LED array panel is similar to the top view shown in
In some embodiments, the space between the adjacent sidewalls of the first mesa structures 2411 can be adjusted. For example, in some embodiments, the space between the adjacent sidewalls of the first mesa structures 2411 is not greater than 50% of the diameter of the first mesa structure 2411. In some embodiments, the space between the adjacent sidewalls of the first mesa structures 2411 is not greater than 30% of the diameter of the first mesa structure 2411. Preferably, the space between the adjacent sidewalls of the first mesa structures 2411 is not greater than 600 nm. Additionally, in some embodiments, the width of the first ion implantation fence 2413 can be adjusted. For example, in some embodiments, the width of the first ion implantation fence 2413 is not greater than 50% of the diameter of the first mesa structure 2411. In some embodiments, the width of the first ion implantation fence 2313 is not greater than 10% of the diameter of the first mesa structure 2311. Preferably, in some embodiments, in the micro-LED array panel, the width of the first ion implantation fence 2413 is not greater than 200 nm. The space between the adjacent sidewalls of the second mesa structure 2421 is not greater than 50% of the diameter of the second mesa structure 2421. In some embodiments, the space between the adjacent sidewalls of the second mesa structure 2421 is not greater than 30% of the diameter of the second mesa structure 2421. Preferably, the space between the adjacent sidewalls of the second mesa structure 2421 is not greater than 600 nm. Additionally, the width of the second ion implantation fence 2423 is not greater than 50% of the diameter of the second mesa structure 2421. In some embodiments, the width of the second ion implantation fence 2423 is not greater than 10% of the diameter of the second mesa structure 2421. Preferably, in the micro-LED array panel, the width of the second ion implantation fence 2423 is not greater than 200 nm.
The micro-LED array panel further includes a bottom isolation layer 2440 filled in the first trench 2412. Preferably, the material of the bottom isolation layer 2440 is one or more of SiO2, SiNx, Al2O3, AlN, HfO2, TiO2, or ZrO2. In addition, an IC backplane 2490 is formed under the first type semiconductor layer 2410 and is electrically connected with the first type semiconductor layer 2410 via a connection structure 2450. The micro-LED array panel further includes a bottom contact 2460 formed at the bottom of the first type semiconductor layer 2410. An upper surface of the connection structure 2450 is connected with the bottom contact 2460 and a bottom of the connection structure 2450 is connected with the IC backplane 2490. The bottom contact 2460 is a protruding contact. In some embodiments, referring to
Referring back to
Furthermore, a dielectric layer 2471 is formed on the sidewalls and bottom of the second trench 2422 under the top conductive layer 2470.
Further detail characters of the micro-LED in the micro-LED array panel can be found by reference to the above described micro-LEDs, which will not be further described here.
The method of manufacturing the micro-LED array panel at least includes manufacturing a micro-LED. Details of manufacturing the micro-LED can be found by reference to the description of steps 501-509 in the Embodiment 1 and the description of steps 1403-1406 in the Embodiment 2, which will not be further described here.
In Embodiments 1-3, a micro lens can be further formed on or above the top of the second type semiconductor layer, such as on the top surface of the top conductive layer, which can be understood by those skilled in the field.
The micro-LED herein has a very small volume. The micro-LED may be an organic LED or an inorganic LED. The micro-LED can be applied in a micro-LED array panel. The light emitting area of the micro-LED array panel is very small, such as 1 mm×1 mm, 3 mm×5 mm. In some embodiments, the light emitting area is the area of the micro-LED array in the micro-LED array panel. The micro-LED array panel includes one or more micro-LED arrays that form a pixel array in which the micro-LEDs are pixels, such as a 1600×1200, 680×480, or 1920×1080 pixel array. The diameter of the micro-LED is in the range of about 200 nm˜2 μm. An IC backplane is formed at the back surface of the micro-LED array and is electrically connected with the micro-LED array. The IC backplane acquires signals such as image data from outside via signal lines to control corresponding micro-LEDs to emit light or not.
The embodiments may further be described using the following clauses:
1. A micro-LED, comprising:
a first type semiconductor layer;
a first type cap layer formed on the first type semiconductor layer; and
a light emitting layer formed on the first type cap layer; wherein
the first type semiconductor layer comprises a mesa structure, a trench, and an ion implantation fence separated from the mesa structure, the trench extending up through the first type semiconductor layer and extending up into at least part of the first type cap layer; and
the ion implantation fence is formed around the trench and the trench is formed around the mesa structure, wherein an electrical resistance of the ion implantation fence is higher than an electrical resistance of the mesa structure.
2. The micro-LED according to clause 1, wherein a top surface of the ion implantation fence is lower than or aligned with a top surface of the first type semiconductor layer.
3. The micro-LED according to clause 1, wherein a bottom surface of the ion implantation fence is aligned with or higher than or lower than a bottom surface of the first type semiconductor layer.
4. The micro-LED according to clause 1, wherein a top surface of the ion implantation fence is lower than a top surface of the trench.
5. The micro-LED according to clause 1, wherein the trench extends up through the first type cap layer.
6. The micro-LED according to clause 5, wherein the trench extends up into at least part of the light emitting layer.
7. The micro-LED according to clause 1, further comprising a second type cap layer formed on a top surface of the light emitting layer, and a second type semiconductor layer formed on the second type cap layer, wherein a conductive type of the second type semiconductor layer is different from the conductive type of the first type semiconductor layer.
8. The micro-LED according to clause 7, wherein the trench further extends up through the first type cap layer, the light emitting layer and into an interior of the second type cap layer.
9. The micro-LED according to clause 8, wherein the trench further extends up through the second type cap layer and into an interior of the second type semiconductor layer.
10. The micro-LED according to clause 9, wherein the trench further extends up through the second type semiconductor layer.
11. The micro-LED according to clause 1, wherein the mesa structure comprises one or more stair structures.
12. The micro-LED according to clause 1, wherein a width of the trench is not greater than 50% of a width of the mesa structure.
13. The micro-LED according to clause 12, wherein the width of the trench is not greater than 200 nm.
14. The micro-LED according to clause 1, wherein the ion implantation fence comprises a light absorption material, and the light absorption material is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN.
15. The micro-LED according to clause 1, wherein a thickness of the first type semiconductor layer is greater than a thickness of the light emitting layer.
16. The micro-LED according to clause 1, further comprising a bottom isolation layer filled in the trench.
17. The micro-LED according to clause 16, wherein a material of the bottom isolation layer is selected from one or more of SiO2, SiNx, Al2O3, AlN, HfO2, TiO2, or ZrO2.
18. The micro-LED according to clause 1, wherein the ion implantation fence is formed by at least implanting ions into the first type semiconductor layer.
19. The micro-LED according to clause 18, wherein the ions implanted into the ion implantation fence are selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
20. The micro-LED according to clause 1, wherein a width of the ion implantation fence is not greater than 50% of a diameter of the mesa structure.
21. The micro-LED according to clause 20, wherein the width of the ion implantation fence is not greater than 200 nm, the diameter of the mesa structure is not greater than 2500 nm, and a thickness of the first type semiconductor layer is not greater than 100 nm.
22. The micro-LED according to clause 7, wherein a material of the first type semiconductor layer is one or more of GaAs, GaP, AlInP, GaN, InGaN, AlGaN, and a material of the second type semiconductor layer is one or more of GaAs, AlInP, GaInP, AlGaAs, AlGaInP, GaN, InGaN and AlGaN.
23. The micro-LED according to clause 1, further comprising an integrated circuit (IC) backplane formed under the first type semiconductor layer and a connection structure electrically connecting the IC backplane with the first type semiconductor layer.
24. The micro-LED according to clause 23, wherein the connection structure is a connection pillar or a metal bonding layer.
25. The micro-LED according to clause 23, further comprising a bottom contact formed on a bottom surface of the first type semiconductor layer, an upper surface of the connection structure being connected with the bottom contact and a bottom surface of the connection structure being connected with the IC backplane.
26. A micro-LED array panel, comprising a plurality of micro-LEDs according to any one of clauses 1 to 25.
27. A method for manufacturing a micro-LED, comprising:
providing an epitaxial structure, wherein the epitaxial structure comprises a first type semiconductor layer, a first type cap layer, a light emitting layer, a second type cap layer, and a second type semiconductor layer sequentially from top to bottom;
patterning the first type semiconductor layer to form a mesa structure, a trench, and a fence;
depositing a bottom contact on the mesa structure; and
performing an ion implantation process into the fence to form an ion implantation fence.
28. The method according to clause 27, wherein after patterning the first type semiconductor layer to form the first mesa structure, the first trench, and the first fence, the method further comprises:
depositing a bottom isolation layer on the first type semiconductor layer and the bottom contact;
patterning the bottom isolation layer to expose the bottom contact;
depositing metal material on the isolation layer and the bottom contact;
grinding the metal material to a top surface of the bottom isolation layer, to form a connection structure; and
turning the epitaxial structure upside down and bonding the connection structure with an Integrated Circuit (IC) backplane.
29. The method according to clause 28, wherein in depositing the bottom isolation layer on the isolation layer and the bottom contact, a material of the bottom isolation layer is selected from one or more of SiO2, SiNx, Al2O3, AlN, HfO2, TiO2, or ZrO2.
30. The method according to clause 28, wherein in providing the epitaxial structure, the epitaxial structure is grown on a substrate.
31. The method according to clause 30, wherein turning the epitaxial structure upside down and bonding the connection structure with the IC backplane further comprises:
removing the substrate.
32. The method according to clause 30, wherein after turning the epitaxial structure upside down and bonding the connection structure with the IC backplane, the method further comprises:
forming a top contact and a top conductive layer on a top surface of the mesa structure.
33. The method according to clause 27, wherein patterning the first type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the first type semiconductor layer to a surface of the light emitting layer.
34. The method according to clause 27, wherein patterning the first type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the first type semiconductor layer and the light emitting layer in sequence, and stopping the etching in the light emitting layer.
35. The method according to clause 27, wherein patterning the first type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the first type semiconductor layer, the light emitting layer, and the second type semiconductor layer in sequence, and stopping the etching in the second type semiconductor layer.
36. The method according to clause 27, wherein depositing the bottom contact on the mesa structure further comprises:
forming a protective mask to protect an area where the bottom contact is not deposited;
depositing material of the bottom contact on the protective mask and on the first type semiconductor layer; and
removing the protective mask from the first type semiconductor layer and removing the material on the protective mask, to form the bottom contact on the mesa structure.
37. The method according to clause 27, wherein performing the ion implantation process into the first fence to form the first ion implantation fence further comprises:
forming a protective mask on an area not being ion implanted while leaving the fence exposed;
implanting ions into the fence; and
removing the protective mask.
38. The method according to clause 37, wherein in performing the ion implantation process into the fence to form the ion implantation fence, implanting with an energy of 0˜500 Kev.
39. The method according to clause 37, wherein in performing the ion implantation process into the fence to form the ion implantation fence, implanting a dose of 1E10˜9E17.
40. The method according to clause 37, wherein in performing the ion implantation process into the fence to form the ion implantation fence, implanting ions into the fence selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
41. The method according to clause 37, wherein in performing the ion implantation process into the fence to form the ion implantation fence, a width of the ion implantation fence is not greater than 50% of a diameter of the mesa structure.
42. The method according to clause 37, wherein in performing the ion implantation process into the fence to form the ion implantation fence, a width of the ion implantation fence is not greater than 200 nm, a diameter of the mesa structure is not greater than 2500 nm, and a thickness of the first type semiconductor layer is not greater than 300 nm.
43. The method according to clause 27, wherein in patterning the first type semiconductor layer to form the mesa structure, the trench, and the fence, a width of the trench is not greater than 50% of a diameter of the mesa structure.
44. The method according to clause 27, wherein a conductive type of the first type semiconductor layer is P type and a conductive type of the second type semiconductor layer is N type, wherein a material of the first type semiconductor layer is selected from one or more of p-GaAs, p-GaP, p-AlInP, p-GaN, p-InGaN, or p-AlGaN, and a material of the second type semiconductor layer is selected from one or more of n-GaAs, n-AlInP, n-GaInP, n-AlGaAs, n-AlGaInP, n-GaN, n-InGaN, or n-AlGaN.
45. The method according to clause 44, wherein the ion implantation fence comprises a light absorption material.
46. The method according to clause 45, wherein the light absorption material is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN.
47. A micro-LED, comprising:
a first type semiconductor layer;
a first type cap layer formed on the first type semiconductor layer;
a light emitting layer formed on the first type cap layer;
a second type cap layer formed on the light emitting layer;
a second type semiconductor layer formed on the second type cap layer; and
an integrated circuit (IC) back plane formed at a bottom surface of the first type semiconductor layer; wherein
the second type semiconductor layer comprises a mesa structure, a trench, and an ion implantation fence separated from the mesa structure, the trench extending down through the second type semiconductor layer and extending down into at least part of the second type cap layer; and
the ion implantation fence is formed around the trench and the trench is formed around the mesa structure, wherein an electrical resistance of the ion implantation fence is higher than an electrical resistance of the mesa structure;
wherein a conductive type of the first type semiconductor layer is different from a conductive type of the second type semiconductor layer.
48. The micro-LED according to clause 47, wherein a bottom surface of the ion implantation fence is higher than or aligned with a bottom surface of the second type semiconductor layer.
49. The micro-LED according to clause 47, wherein a top surface of the ion implantation fence is aligned with or higher than or lower than a top surface of the second type semiconductor layer.
50. The micro-LED according to clause 47, wherein a bottom surface of the ion implantation fence is higher than a bottom surface of the trench.
51. The micro-LED according to clause 47, wherein the trench extends down through the second type cap layer.
52. The micro-LED according to clause 51, wherein the trench further extends down into at least part of the light emitting layer.
53. The micro-LED according to clause 52, wherein the trench further extends down through the light emitting layer and into an interior of the first type cap layer; or the trench further extends down through the light emitting layer and the first type cap layer and extends into an interior of the first type semiconductor layer.
54. The micro-LED according to clause 53, wherein the trench further extends down through the first type semiconductor layer.
55. The micro-LED according to clause 47, wherein the mesa structure comprises one or more stair structures.
56. The micro-LED according to clause 47, wherein a width of the trench is not greater than 50% of a width of the mesa structure.
57. The micro-LED according to clause 56, wherein a width of the trench is not greater than 200 nm.
58. The micro-LED according to clause 47, wherein the ion implantation fence comprises a light absorption material, and the light absorption material is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN.
59. The micro-LED according to clause 47, wherein a thickness of the second type semiconductor layer is larger than a thickness of the light emitting layer.
60. The micro-LED according to clause 47, further comprising a bottom isolation layer formed between a bottom surface of the first type semiconductor layer and a top surface of the IC backplane.
61. The micro-LED according to clause 60, wherein a material of the bottom isolation layer is selected from one or more of SiO2, SiNx, Al2O3, AlN, HfO2, TiO2, or ZrO2.
62. The micro-LED according to clause 47, wherein the ion implantation fence is formed by at least implanting ions into the second type semiconductor layer.
63. The micro-LED according to clause 62, wherein the ions implanted into the second type semiconductor layer are selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
64. The micro-LED according to clause 47, wherein a width of the ion implantation fence is not greater than 50% of a diameter of the mesa structure.
65. The micro-LED according to clause 62, wherein the width of the ion implantation fence is not greater than 200 nm, the diameter of the mesa structure is not greater than 2500 nm, and a thickness of the first type semiconductor layer is not greater than 300 nm.
66. The micro-LED according to clause 47, wherein a material of the first type semiconductor layer is one or more of GaAs, GaP, AlInP, GaN, InGaN, AlGaN, and a material of the second type semiconductor layer is one or more of GaAs, AlInP, GaInP, AlGaAs, AlGaInP, GaN, InGaN and AlGaN.
67. The micro-LED according to clause 47, further comprising a connection structure electrically connecting the IC backplane with the first type semiconductor layer.
68. The micro-LED according to clause 67, wherein the connection structure is a connection pillar or a metal bonding layer.
69. The micro-LED according to clause 67, further comprising a bottom contact formed on a bottom surface of the first type semiconductor layer, an upper surface of the connection structure being connected with the bottom contact and a bottom surface of the connection structure being connected with the IC backplane.
70. A micro-LED array panel, comprising a plurality of micro-LEDs according to any one of clauses 47 to 69.
71. A method for manufacturing a micro-LED, comprising:
providing an epitaxial structure, wherein the epitaxial structure comprises a first type semiconductor layer, a first type cap layer, a light emitting layer, a second type cap layer, and a second type semiconductor layer sequentially from top to bottom;
bonding the epitaxial structure with an integrated circuit (IC) backplane;
patterning the second type semiconductor layer to form a mesa structure, a trench, and a fence;
depositing a top contact on the mesa structure;
performing an ion implantation process into the fence; and
depositing a top conductive layer on a top surface of the second type semiconductor layer, on a top contact, and in the trench.
72. The method according to clause 71, wherein providing the epitaxial structure further comprises:
depositing a bottom contact layer on a top surface of the first type semiconductor layer; and
depositing a metal bonding layer on a top surface of the bottom contact layer.
73. The method according to clause 72, wherein bonding the epitaxial structure with the IC backplane further comprises:
turning the epitaxial structure upside down; and
bonding the metal bonding layer with a contact pad of the IC backplane.
74. The method according to clause 73, wherein in providing the epitaxial structure, the epitaxial structure is grown on a substrate.
75. The method according to clause 74, wherein bonding the epitaxial structure with the IC backplane further comprises:
removing the substrate.
76. The method according to clause 71, wherein patterning the second type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the second type semiconductor layer to a surface of the light emitting layer.
77. The method according to clause 71, wherein patterning the second type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the second type semiconductor layer and the light emitting layer in sequence, and
stopping the etching in the light emitting layer.
78. The method according to clause 71, wherein the patterning the second type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the second type semiconductor layer, the light emitting layer, and the first type semiconductor layer in sequence, and
stopping the etching in the first type semiconductor layer.
79. The method according to clause 71, wherein depositing the top contact on the mesa structure further comprises:
forming a protective mask to protect an area where the bottom contact is not being deposited;
depositing a material of the top contact on the protective mask;
removing the protective mask from the second type semiconductor layer and removing the material of the top contact on the protective mask, to form the top contact on the mesa structure.
80. The method according to clause 71, wherein performing the ion implantation process into the fence further comprises:
forming a protective mask on an area not being ion implanted while leaving the fence exposed;
implanting ions into the fence; and
removing the protective mask.
81. The method according to clause 80, wherein in performing the ion implantation process into the fence, implanting with an energy 0˜500 KeV.
82. The method according to clause 80, wherein in performing the ion implantation process into the fence, implanting a dose of 1E10˜9E17.
83. The method according to clause 80, wherein in performing the ion implantation process into the fence, implanting ions into the ion implantation fence selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
84. The method according to clause 80, wherein in performing the ion implantation process into the fence, a width of the ion implantation fence is not greater than 50% of a diameter of the mesa structure.
85. The method according to clause 80 wherein in performing the ion implantation process into the fence, a width of the ion implantation fence is not greater than 200 nm, a diameter of the mesa structure is not greater than 2500 nm, and a thickness of the second type semiconductor layer is not greater than 100 nm.
86. The method according to clause 71, wherein a conductive type of the first type semiconductor layer is P type and a conductive type of the second type semiconductor layer is N type; wherein a material of the first type semiconductor layer is selected from one or more of p-GaAs, p-GaP, p-AlInP, p-GaN, p-InGaN, or p-AlGaN, and a material of the second type semiconductor layer is selected from one or more of n-GaAs, n-AlInP, n-GaInP, n-AlGaAs, n-AlGaInP, n-GaN, n-InGaN, or n-AlGaN.
87. The method according to clause 86, wherein the ion implantation fence comprises a light absorption material.
88. The method according to clause 87, wherein the light absorption material is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN.
89. A micro-LED, comprising:
a first type semiconductor layer;
a first type cap layer formed on the first type semiconductor layer;
a light emitting layer formed on the first type cap layer;
a second type cap layer formed on the light emitting layer; and
a second type semiconductor layer formed on the second type cap layer;
wherein the first type semiconductor layer comprises a first mesa structure, a first trench, and a first ion implantation fence separated from the first mesa structure, the first trench extending up through the first type semiconductor layer and extending up into at least part of the first type cap layer; and
the first ion implantation fence is formed around the first trench and the first trench is formed around the first mesa structure; and an electrical resistance of the first ion implantation fence is higher than an electrical resistance of the first mesa structure; and
the second type semiconductor layer comprises a second mesa structure, a second trench, and a second ion implantation fence separated from the second mesa structure; and
the second ion implantation fence is formed around the second trench and the second trench is formed around the second mesa structure; and an electrical resistance of the second ion implantation fence is higher than an electrical resistance of the second mesa structure;
wherein a conductive type of the first type semiconductor layer is different from a conductive type of the second type semiconductor layer.
90. The micro-LED according to clause 89, wherein a top surface of the first trench does not touch the bottom of the second trench; and part of the light emitting layer is disposed between the top surface of the first trench and the bottom surface of the second trench.
91. The micro-LED according to clause 90, wherein a top surface of the first ion implantation fence is lower than or aligned with a top surface of the first type semiconductor layer; and a bottom surface of the second ion implantation fence is higher than or aligned with a bottom surface of the second type semiconductor layer.
92. The micro-LED according to clause 89, wherein a bottom surface of the first ion implantation fence is aligned with or higher than or lower than a bottom surface of the first type semiconductor layer; and
a top surface of the second ion implantation fence is aligned with or higher than or lower than a top surface of the second type semiconductor layer.
93. The micro-LED according to clause 89, wherein a top surface of the first ion implantation fence is lower than a top surface of the first trench.
94. The micro-LED according to clause 89, wherein the second trench does not extend down through the second type semiconductor layer.
95. The micro-LED according to clause 94, wherein the second trench extends down through the second type semiconductor layer and extends down into at least part of the second type cap layer, or extends down through the second type cap layer and extends down into at least part of the light emitting layer.
96. The micro-LED according to clause 95, wherein a bottom surface of the second ion implantation fence is higher than a bottom surface of the second trench.
97. The micro-LED according to clause 89, wherein a top surface of the first trench is directly connected with a bottom surface of the second trench, without the light emitting layer disposed between the first trench and the second trench.
98. The micro-LED according to clause 89, wherein the first mesa structure comprises one or more stair structures and the second mesa structure comprises one or more stair structures.
99. The micro-LED according to clause 89, wherein a width of the first trench is not greater than 50% of a width of the first mesa structure; and/or, a width of the second trench is not greater than 50% of a width of the second mesa structure.
100. The micro-LED according to clause 99, wherein the width of the first trench is not greater than 200 nm; and/or, the width of the second trench is not greater than 200 nm.
101. The micro-LED according to clause 89, wherein the first ion implantation fence comprises a first light absorption material, and the second ion implantation fence comprises a second light absorption material; wherein a conductive type of the first light absorption material is the same as a conductive of the first type semiconductor layer, and a conductive type of the second light absorption material is the same as a conductive of the second type semiconductor layer.
102. The micro-LED according to clause 101, wherein the first light absorption material is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN; and/or, the second light absorption material is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN.
103. The micro-LED according to clause 89, wherein a thickness of the first type semiconductor layer is greater than a thickness of the light emitting layer, a thickness of the second type semiconductor layer is greater than the thickness of the light emitting layer, and the thickness of the first type semiconductor layer is greater than the thickness of the second type semiconductor layer.
104. The micro-LED according to clause 89, further comprising a bottom isolation layer formed between a bottom surface of the first type semiconductor layer and a top surface of the IC backplane.
105. The micro-LED according to clause 104, wherein a material of the bottom isolation layer is selected from one or more of SiO2, SiNx, Al2O3, AlN, HfO2, TiO2, or ZrO2.
106. The micro-LED according to clause 89, wherein the first ion implantation fence is formed by at least implanting ions into the first type semiconductor layer and the second ion implantation fence is formed by at least implanting ions into the second type semiconductor layer.
107. The micro-LED according to clause 106, wherein the ions implanted into the first type semiconductor layer are selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F; the ions implanted into the second type semiconductor layer are selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
108. The micro-LED according to clause 89, wherein a width of the first ion implantation fence is not greater than 50% of a diameter of the first mesa structure, and a width of the second ion implantation fence is not greater than 50% of a diameter of the second mesa structure.
109. The micro-LED according to clause 108, wherein the width of the first ion implantation fence is not greater than 200 nm, the diameter of the first mesa structure is not greater than 2500 nm, and a thickness of the first type semiconductor layer is not greater than 100 nm; and
the width of the second ion implantation fence is not greater than 200 nm, the diameter of the second mesa structure is not greater than 2500 nm, and a thickness of the second type semiconductor layer is not greater than 300 nm.
110. The micro-LED according to clause 89, wherein a material of the first type semiconductor layer is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN; and a material of the second type semiconductor layer is selected from one or more of GaAs, AlInP, GaInP, AlGaAs, AlGaInP, GaN, InGaN, or AlGaN.
111. The micro-LED according to clause 89, further comprising an integrated circuit (IC) backplane formed under the first type semiconductor layer and a connection structure electrically connecting the IC backplane with the first type semiconductor layer.
112. The micro-LED according to clause 111, wherein the connection structure is a connection pillar or a metal bonding layer.
113. The micro-LED according to clause 111, further comprising: comprising a bottom contact formed on a bottom surface of the first type semiconductor layer, an upper a connection structure 1550 surface of the connection structure being connected with the bottom contact and a bottom surface of the connection structure being connected with the IC backplane.
114. A micro-LED array panel, comprising a plurality of micro-LEDs according to any one of clauses 89 to 113.
115. A method for manufacturing a micro-LED, comprising:
a process I comprising patterning a first type semiconductor layer; and implanting first ions into the first type semiconductor layer; and
a process II comprising patterning a second type semiconductor layer; and implanting second ions into the second type semiconductor layer.
116. The method according to clause 115, wherein the process I further comprises:
providing an epitaxial structure, wherein the epitaxial structure comprises a first type semiconductor layer, a first type cap layer, a light emitting layer, a second type cap layer, and a second type semiconductor layer sequentially from top to bottom;
patterning the first type semiconductor layer to form a mesa structure, a trench, and a fence;
depositing a bottom contact on the mesa structure;
performing an ion implantation process into the fence, to form an ion implantation fence;
depositing a bottom isolation layer on the first type semiconductor layer and the bottom contact;
patterning the bottom isolation layer to expose the bottom contact;
depositing metal material on the isolation layer and the bottom contact;
grinding the metal material to a top surface of the bottom isolation layer, to form a connection structure; and
turning the epitaxial structure upside down and bonding the connection structure with an integrated circuit (IC) backplane.
117. The method according to clause 116, wherein patterning the first type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the first type semiconductor layer to a surface of the light emitting layer.
118. The method according to clause 116, wherein patterning the first type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the first type semiconductor layer and the light emitting layer in sequence, and
stopping the etching in the light emitting layer.
119. The method according to clause 116, wherein patterning the first type semiconductor layer to form the mesa structure, the trench, and the fence further comprises:
etching the first type semiconductor layer, the light emitting layer, and the second type semiconductor layer in sequence, and
stopping the etching in the second type semiconductor layer.
120. The method according to clause 116, wherein depositing a bottom contact on the mesa structure further comprises:
forming a protective mask to protect an area where the bottom contact is not being deposited;
depositing a material of the bottom contact on the protective mask and on the first type semiconductor layer; and
removing the protective mask from the first type semiconductor layer and removing the material on the protective mask, to form the bottom contact on the mesa structure.
121. The method according to clause 116, wherein performing the ion implantation process into the fence to form the ion implantation fence further comprises:
forming a protective mask on an area not being ion implanted while leaving the fence exposed;
implanting ions into the fence; and
removing the protective mask.
122. The method according to clause 121, wherein in performing the ion implantation process into the fence to form the ion implantation fence, implanting with an energy of 0˜500 Kev, and implanting a dose of 1E10˜9E17.
123. The method according to clause 121, wherein in performing the ion implantation process into the fence to form the ion implantation fence, implanting ions into the fence selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
124. The method according to clause 121, wherein in performing the ion implantation process into the fence to form the ion implantation fence, a width of the ion implantation fence is not greater than 50% of a diameter of the mesa structure, the width of the ion implantation fence is not greater than 200 nm, the diameter of the mesa structure is not greater than 2500 nm, and a thickness of the first type semiconductor layer is not greater than 300 nm.
125. The method according to clause 116, wherein in patterning the first type semiconductor layer to form the mesa structure, the trench, and the fence, a width of the trench is not greater than 50% of a diameter of the mesa structure.
126. The method according to clause 115, wherein the mesa structure, the trench, and the fence are a first mesa structure, a first trench, and a first fence, respectively; wherein the process II further comprises:
patterning the second type semiconductor layer to form a second mesa structure, a second trench, and a second fence;
depositing a top contact on the second mesa structure;
performing an ion implantation process into the second fence;
depositing a top conductive layer on a top surface of the second type semiconductor layer, on the top contact, and in the second trench.
127. The method according to clause 126, wherein patterning the second type semiconductor layer to form the second mesa structure, the second trench, and the second fence further comprises:
etching the second type semiconductor layer to a surface of the light emitting layer.
128. The method according to clause 126, wherein patterning the second type semiconductor layer to form the second mesa structure, the second trench, and the second fence further comprises:
etching the second type semiconductor layer and the light emitting layer in sequence, and
stopping the etching in the light emitting layer.
129. The method according to clause 126, wherein patterning the second type semiconductor layer to form the second mesa structure, the second trench, and the second fence further comprises:
etching the second type semiconductor layer, the light emitting layer and the first type semiconductor layer in sequence, and
stopping the etching in the first type semiconductor layer.
130. The method according to clause 126, wherein depositing the top contact on the second mesa structure further comprises:
forming a protective mask to protect an area where the bottom contact is not being deposited;
depositing a material of the top contact on the protective mask;
removing the protective mask from the second type semiconductor layer and removing the material of the top contact on the protective mask, to form the top contact on the second mesa structure.
131. The method according to clause 126, wherein performing the ion implantation process into the second fence further comprises:
forming a protective mask on an area not being implanted while leaving the second fence exposed;
implanting the ions into the second fence; and
removing the protective mask.
132. The method according to clause 125, wherein in performing the ion implantation process into the second fence, implanting with an energy of 0˜500 KeV and implanting a dose of 1E10˜9E17.
133. The method according to clause 125, wherein in performing the ion implantation process into the second fence, implanting ions into the second fence selected from one or more of H, N, Ar, Kr, Xe, As, O, C, P, B, Si, S, Cl, or F.
134. The method according to clause 125, wherein in performing the ion implantation process into the second fence, a width of the second ion implantation fence is not greater than 50% of a diameter of the second mesa structure, the width of the second ion implantation fence is not greater than 200 nm, the diameter of the second mesa structure is not greater than 2500 nm, and a thickness of the second type semiconductor layer is not greater than 100 nm.
135. The method according to clause 116, wherein in providing the epitaxial structure, the epitaxial structure is grown on a substrate; the turning the epitaxial structure upside down and bonding the connection structure with the IC backplane further comprises:
removing the substrate.
136. The method according to clause 116, wherein in depositing the bottom isolation layer on the first type semiconductor layer and the bottom contact, a material of the bottom isolation layer is selected from one or more of SiO2, SiNx, Al2O3, AlN, HfO2, TiO2, or ZrO2.
137. The method according to clause 116, wherein the ion implantation fence comprises a light absorption material.
138. The method according to clause 137, wherein a conductive type of the light absorption material is the same as a conductive type of the first type semiconductor layer, and the light absorption material is selected from one or more of GaAs, GaP, AlInP, GaN, InGaN, or AlGaN.
139. The method according to clause 116, wherein a conductive type of the first type semiconductor layer is P type and a conductive type of the second type semiconductor layer is N type; and a material of the first type semiconductor layer is selected from one or more of p-GaAs, p-GaP, p-AlInP, p-GaN, p-InGaN or p-AlGaN; and a material of the second type semiconductor layer is selected from one or more of n-GaAs, n-AlInP, n-GaInP, n-AlGaAs, n-AlGaInP, n-GaN, n-InGaN, or n-AlGaN.
It should be noted that relational terms herein such as “first” and “second” are used only to differentiate an entity or operation from another entity or operation, and do not require or imply any actual relationship or sequence between these entities or operations. Moreover, the words “comprising,” “having,” “containing,” and “including,” and other similar forms are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items.
As used herein, unless specifically stated otherwise, the term “or” encompasses all possible combinations, except where infeasible. For example, if it is stated that a database may include A or B, then, unless specifically stated otherwise or infeasible, the database may include A, or B, or A and B. As a second example, if it is stated that a database may include A, B, or C, then, unless specifically stated otherwise or infeasible, the database may include A, or B, or C, or A and B, or A and C, or B and C, or A and B and C.
In the foregoing specification, embodiments have been described with reference to numerous specific details that can vary from implementation to implementation. Certain adaptations and modifications of the described embodiments can be made. Other embodiments can be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. It is also intended that the sequence of steps shown in figures are only for illustrative purposes and are not intended to be limited to any particular sequence of steps. As such, those skilled in the art can appreciate that these steps can be performed in a different order while implementing the same method.
In the drawings and specification, there have been disclosed exemplary embodiments. However, many variations and modifications can be made to these embodiments. Accordingly, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.
Number | Date | Country | Kind |
---|---|---|---|
PCT/CN2022/075282 | Jan 2022 | WO | international |
The disclosure claims the benefits of priority to PCT Application No. PCT/CN2022/075282, filed on Jan. 31, 2022, which is incorporated herein by reference in its entirety.