This application claims the right of priority based on TW application Serial No. 110131037, filed on Aug. 23, 2021, which is incorporated by reference herein in their entirety.
The present disclosure relates to a semiconductor device, in particular, to a semiconductor optoelectronic device such as a light-emitting device (such as a light-emitting diode (LED)).
A group III-V semiconductor material containing a group III element and a group V element may be applied to various optoelectronic devices, such as light emitting diodes (LEDs), laser diodes (LDs), photoelectric detectors, solar cells or power devices (such as switches or rectifiers). These optoelectronic devices can be applied in various fields, such as illumination, medical care, display, communication, sensing, or power supply system. For example, in light-emitting devices, LEDs have low energy consumption and long operating lifetime, and are widely used.
The present disclosure provides a semiconductor device. The semiconductor device includes a first semiconductor structure, a second semiconductor structure, and an active region. The first semiconductor structure includes a first semiconductor layer which includes a first dopant and a second dopant. The second semiconductor structure is located on the first semiconductor structure and includes the first dopant. The active region is located between the first semiconductor structure and the second semiconductor structure and includes the first dopant. The first dopant and the second dopant have different conductivity types.
The following embodiments will be described with accompany drawings to disclose the concept of the present disclosure. In the drawings or description, same or similar portions are indicated with same or similar numerals. Furthermore, a shape or a size of a member in the drawings may be enlarged or reduced. Particularly, it should be noted that a member which is not illustrated or described in drawings or description may be in a form that is known by a person skilled in the art.
In the present disclosure, if not otherwise specified, the general formula InGaP represents Inx0Ga1-x0P, wherein 0<x0<1; the general formula AlInP represents Alx1In1-x1P, wherein 0<x1<1; the general formula AlGaInP represents Alx2Gax3In1-x2-x3P, wherein 0<x2<1 and 0<x3<1; the general formula InGaAsP represents Inx4Ga1-x4Asx5P1-x5, wherein 0<x4<1 , 0<x5<1; the general formula AlGaInAs represents Alx6Gax7In1-x6-x7As, wherein 0<x6<1 and 0<x7<1; the general formula InGaAs represents Inx8Ga1-x8As, wherein 0<x8<1; the general formula AlGaAs represents Alx9Ga1-x9As, wherein 0<x9<1; the general formula InGaN represents Inx10Ga1-x10N, wherein 0<x10<1; the general formula AlGaN represents Alx11Ga1-x11N, wherein 0<x11<1; the general formula AlGaAsP represents Alx12Ga1-x12Asx13P1-x13, wherein 0<x12<1 and 0<x13<1; the general formula InGaAsN represents Inx14Ga1-x14Asx15N1-x15, wherein 0<x14<1 and 0<x15<1; the general formula AlInGaN represents Alx16Inx17Ga1-x16-x17N, wherein 0<x16<1 and 0<x17<1. The content of each element may be adjusted for different purposes, for example, for adjusting the energy gap, or the peak wavelength or dominant wavelength when the semiconductor device is a light-emitting device. However, the present disclosure is not limited thereto.
For example, the semiconductor device of the present disclosure is a light-emitting device (such as a light-emitting diode or a laser diode), a light absorbing device (such as a photo-detector) or a non-optoelectronic device. Analysis of the composition and/or dopant contained in each layer of the semiconductor device of the present disclosure may be conducted by any suitable method such as a secondary ion mass spectrometer (SIMS). A thickness of each layer may be obtained by any suitable method, such as a transmission electron microscopy (TEM) or a scanning electron microscope (SEM).
A person skilled in the art can realize that addition of other components based on a structure recited in the following embodiments is allowable. For example, if not otherwise specified, a description similar to “a first layer/structure is on or under a second layer/structure” may include an embodiment in which the first layer/structure directly (or physically) contacts the second layer/structure, and may also include an embodiment in which another structure is provided between the first layer/structure and the second layer/structure, such that the first layer/structure and the second layer/structure do not physically contact each other. In addition, it should be realized that a positional relationship of a layer/structure may be altered when being observed in different orientations.
Furthermore, in the present disclosure, a description of “a layer/structure only includes M material” means the M material is the main constituent of the layer/structure; however, the layer/structure may still contain a dopant or unavoidable impurities.
As shown in
As shown in
The base 100 may include conductive or insulating materials. The conductive materials may include gallium arsenide (GaAs), indium phosphide (InP), silicon carbide (SiC), gallium phosphide (GaP), zinc oxide (ZnO), gallium nitride (GaN), aluminum nitride (AlN), germanium (Ge) or silicon (Si). The insulating material may include sapphire. In an embodiment, the base 100 is a growth substrate, that is, the epitaxial structure 102 can be formed on the base 100 by an epitaxial method such as metal-organic chemical vapor deposition (MOCVD). In an embodiment, the base 100 is a bonding substrate instead of a growth substrate, and the base 100 can be bonded to the epitaxial structure 102 by an adhesive material layer (not shown).
The first semiconductor structure 104 and the second semiconductor structure 106 may have different conductivity types. For example, the first semiconductor structure 104 is n-type and the second semiconductor structure 106 is p-type, or the first semiconductor structure 104 is p-type and the second semiconductor structure 106 is n-type. Thereby, the first semiconductor structure 104 and the second semiconductor structure 106 can respectively provide electrons and holes, or holes and electrons. The first semiconductor structure 104, the second semiconductor structure 106, and the active region 108 may include an III-V semiconductor material. The III-V semiconductor material may include aluminum (Al), gallium (Ga), arsenic (As), phosphorus (P), nitrogen (N), or indium (In). In an embodiment, the first semiconductor structure 104, the second semiconductor structure 106, and the active region 108 may not contain nitrogen (N). Specifically, the III-V semiconductor material can be a binary compound semiconductor (such as GaAs, GaP or GaN), a ternary compound semiconductor (such as InGaAs, AlGaAs, InGaP, AlInP, InGaN or AlGaN) or a quaternary compound semiconductor (such as AlGaInAs, AlGaInP, AlInGaN, InGaAsP, InGaAsN or AlGaAsP). In an embodiment, the active region 108 only include a ternary compound semiconductor (such as InGaAs, AlGaAs, InGaP, AlInP, InGaN, or AlGaN) or a quaternary compound semiconductor (such as AlGaInAs, AlGaInP, AlInGaN, InGaAsP, InGaAsN, or AlGaAsP).
The epitaxial structure 102 may include a double heterostructure (DH), a double-side double heterostructure (DDH) or a multiple quantum well (MQW) structure. According to an embodiment, when the semiconductor device 10 is a light-emitting device, the active region 108 may emit a light during operation of the semiconductor device 10. The light includes visible light or invisible light. The light emitted by the semiconductor device 10 is determined by the material composition of the active region 108. For example, when the material of the active region 108 includes InGaN, it may emit a blue light with a peak wavelength of 400 nm to 490 nm, a deep blue light or a green light with a peak wavelength of 490 nm to 550 nm; when the material of the active region 108 includes AlGaN, it may emit ultraviolet light with a peak wavelength of 250 nm to 400 nm; when the material of the active region 108 includes InGaAs, InGaAsP, AlGaAs or AlGaInAs, it may emit an infrared light with a peak wavelength of 700 to 1700 nm; when the material of the active region 108 includes InGaP or AlGaInP, it may emit a red light with a peak wavelength of 610 nm to 700 nm, or a yellow light with a peak wavelength of 530 nm to 600 nm.
In an embodiment, the active region 108 may include a first confinement layer 108a, a second confinement layer 108b, and one or more semiconductor stacks 108c between the first confinement layer 108a and the second confinement layer 108b. Each semiconductor stack 108c includes a barrier layer 108c1 and a well layer 108c2. In an embodiment, the number of the semiconductor stacks 108c may be greater than or equal to two. In an embodiment, the number of the semiconductor stacks 108c may be 20 or less, and may be 10 or less. For example, the number of the semiconductor stacks 108c is 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, or 19. In an embodiment, when the active region 108 includes five or less semiconductor stacks 108c (i.e., five or less barrier layers 108c1 and five or less well layers 108c2), the semiconductor device 10 can have a relatively high quantum efficiency, especially when the semiconductor device 10 is operated at a low current density (such as 1 A/cm2 or less) or a low current (such as 10 mA or less). Specifically, the current density can be obtained by dividing the magnitude of the current (unit: ampere (A)) applied to the semiconductor device 10 by a top-view area of the epitaxial structure 102 (unit: cm2). In an embodiment, the top-view area of the epitaxial structure 102 may be in the range of 1 μm2 to 2500 μm2, such as 50 μm2 to 100 μm2, 600 μm2, 1200 μm2, 1500 μm2 or 2000 m2. When the epitaxial structure 102 has a plurality of areas with different sizes in a top view, the top-view area refers to the largest one of these areas.
The barrier layer 108c1 and/or the well layer 108c2 may include aluminum (Al). In an embodiment, the active region 108 includes n semiconductor stacks 108c and has n barrier layers 108c1 and n well layers 108c2, wherein n is a positive integer (i.e., n barrier layers 108c1 includes a first barrier layer, a second barrier layer . . . and a n-th barrier layer, and n well layers 108c2 includes a first well layer, a second well layer . . . and a n-th well layer). Each barrier layer 108c1 may have a first aluminum content percentage (ai %, wherein i=1, 2 . . . n), and each well layer 108c2 may have a second aluminum content percentage (bi %, wherein i=1, 2 . . . n). For example, the first barrier layer 108c1 has a first aluminum content percentage a1%, the second barrier layer 108c1 has a first aluminum content percentage a2%, and the n-th barrier layer 108c1 has a first aluminum content percentage an %; the first well layer 108c2 has a second aluminum content percentage b1%, the second well layer 108c2 has a second aluminum content percentage b2%, and the n-th well layer 108c2 has a second aluminum content percentage bn %. In an embodiment, the first aluminum content percentages in each barrier layer 108c1 may be the same or different. The difference in aluminum content percentage (Al %) between the barrier layers 108c1 may be between 0 to 1 atom %. In an embodiment, the second aluminum content percentage in each the well layer 108c2 may be the same or different. The difference in aluminum content percentage (Al %) between the well layers 108c2 may be between 0 to 1 atom %.
Specifically, the first and second aluminum content percentages refer to the atomic percentages (atom %) of Al in the barrier layer 108c1 and the well layer 108c2, respectively. For example, the first and second aluminum content percentages can be obtained by analyzing the barrier layer 108c1 and the well layer 108c2 with an Energy Dispersive X-ray spectrometer (EDX). As an example, when the barrier layer 108c1 includes Alz1Ga0.5-z1In0.5P (wherein 0≤z1≤0.5), and the well layer 108c2 includes Alz2Ga0.5-z2In0.5P (wherein 0≤z2≤0.5), z1 and z2 can be obtained from EDX analysis. Here, the first aluminum content percentage (ai %) of the barrier layer 108c1 can be defined as z1*100%, and the second aluminum content percentage (bi %) of the well layer 108c2 can be defined as z2*100%. That is, the aluminum content percentage represents the ratio of Al to the sum of the atomic percentages of all the group III elements. For example, when z1=0.3, it means that the first aluminum content percentage is 30%. In an embodiment, the aluminum content percentages of the barrier layer 108c1 and the well layer 108c2 can also be obtained by a SIMS analysis. In an embodiment, the first aluminum content percentage is greater than the second aluminum content percentage. In an embodiment, the first aluminum content percentage may be in the range of 15% to 50%, such as 20%, 25%, 30%, 35%, 40%, 45% or 50%. In an embodiment, the second aluminum content percentage may be in the range of 0% to 15%, such as 5% or 10%. In an embodiment, when the percentage of the first aluminum content is greater than or equal to 25%, the ability of the barrier layer 108c1 to confine electrons can be further improved, resulting in better quantum efficiency (such as better external quantum efficiency (EQE) or internal quantum efficiency (IQE)). In an embodiment, when the percentage of the first aluminum content is greater than or equal to 35%, a better quantum efficiency can be obtained.
In an embodiment, the active region 108 includes n semiconductor stacks 108c (i.e., n barrier layers 108c1 and n well layers 108c2), wherein n is a positive integer. Each barrier layer 108c1 has a first thickness (t1i, wherein i=1, 2 . . . n), and each well layer 108c2 has a second thickness (t2i, wherein i=1, 2 . . . n). The first thickness may be greater than or equal to the second thickness. The first barrier layer 108c1 has a first thickness t11, the second barrier layer 108c1 has a first thickness t12, the n-th barrier layer 108c1 has a first thickness t1n, the first well layer 108c2 has a second thickness t21, the second well layer 108c2 has a second thickness t22, and the n-th well layer 108c2 has a second thickness t2n. In an embodiment, the first thicknesses of the barrier layers 108c1 may be the same or different, and the thickness difference between the barrier layers 108c1 may be between 0 to 1 nm. In an embodiment, the second thicknesses of the well layers 108c2 may be the same or different, and the thickness difference between the well layers 108c2 may be between 0 to 1 nm. The first thickness and the second thickness may be less than or equal to 200 Å, such as about 150 Å, 100 Å, 50 Å, or 10 Å. In an embodiment, when the thicknesses of the barrier layer 108c1 and the well layer 108c2 are both less than or equal to 200 Å, the semiconductor device 10 may have a better quantum efficiency. In an embodiment, the ratio of the first thickness (t1i) to the second thickness (t2i) is in the range of 2:1 to 40:1. For example, the ratio of the first thickness to the second thickness (t1i/t2i) may be in the range of 10:1 to 35:1. By having a larger first thickness, the ability of the barrier layer 108c1 to confine electrons can be improved. In an embodiment, the first thickness may be in the range of 20 Å to 4000 Å. For example, the first thickness may be greater than or equal to 100 Å and less than or equal to 2000 Å. The second thickness may be in the range of 10 Å to 200 Å, such as 150 Å, 100 Å or 50 Å.
As shown in
In an embodiment, the first semiconductor structure 104 includes a first dopant and a second dopant different from the first dopant. Specifically, the first semiconductor layer 116 and/or the second semiconductor layer 118 may contain the first dopant and the second dopant. In an embodiment, the second dopant is continuously distributed in the first semiconductor structure 104 (such as the first semiconductor layer 116 and the second semiconductor layer 118). For example, in a SIMS analysis of the semiconductor structure 104, the signal of the second dopant can be obtained at each depth position in the semiconductor structure 104. With respect to the first semiconductor structure 104 (i.e., the first semiconductor layer 116 and the second semiconductor layer 118), the first dopant and the second dopant have different conductivity types (such as p-type and n-type, or n-type and p-type, respectively). In an embodiment, the first semiconductor structure 104 includes the first dopant and the second dopant, and the conductivity type of the first semiconductor structure 104 is n-type. In an embodiment, the first semiconductor structure 104 includes the first dopant and the second dopant, and the conductivity type of the first semiconductor structure 104 is p-type.
According to an embodiment, the first dopant has a first maximum concentration (C1) in the first semiconductor structure 104, and the second dopant has a second maximum concentration (C2) in the first semiconductor structure 104 greater than the first maximum concentration (C1). In an embodiment, the first maximum concentration (C1) and the second maximum concentration (C2) are located at or near an interface between the first semiconductor layer 116 and the second semiconductor layer 118. In an embodiment, the conductivity type of the first semiconductor structure 104 is determined by the concentrations of the first dopant and the second dopant. For example, when the second dopant is an n-type dopant and the concentration of the second dopant in the first semiconductor structure 104 is greater than that of the first dopant, the conductivity type of the first semiconductor structure 104 is n-type. By contrast, when the second dopant is a p-type dopant and the concentration of the second dopant in the first semiconductor structure 104 is greater than that of the first dopant, the conductivity type of the first semiconductor structure 104 is p-type. In an embodiment, according to the concentration relationship between the first and second dopants, the first semiconductor structure 104 can be divided into a first region and a second region. The concentration of the second dopant is greater than that of the first dopant in the first region, and the concentration of the second dopant is smaller than the concentration of the first dopant in the second region. In this case, when the second dopant is an n-type dopant, the conductivity type of the first region in the first semiconductor structure 104 can be n-type, and the conductivity type of the second region can be p-type; by contrast, when the second dopant is a p-type dopant, the conductivity type of the first region in the first semiconductor structure 104 may be p-type, and the conductivity type of the second region may be n-type. The first region and the second region do not overlap. The first region (or the second region) may be entirely located in the first semiconductor layer 116 or the second semiconductor layer 118. Alternatively, the first region (or the second region) may be in the first semiconductor layer 116 and the second semiconductor layer 118. For example, the first region may have a first part in the first semiconductor layer 116 and a second part in the second semiconductor layer 118 (i.e., the first region extends across the interface between the first semiconductor layer 116 and the second semiconductor layer 118), and the rest portion of the first semiconductor structure 104 that does not overlap with the first region belongs to the second region. In an embodiment, the first dopant and the second dopant may be group II, group IV or group VI elements in the periodic table of elements. In an embodiment, the first dopant and the second dopant are group VI and group II elements, respectively. Specifically, the first dopant and the second dopant can be respectively C, Zn, Si, Ge, Sn, Se, Mg or Te.
In an embodiment, the first semiconductor structure 104 may further include a superlattice structure (not shown) located between the first semiconductor layer 116 and the second semiconductor layer 118 to further improve the current distribution. The superlattice structure can be made by alternately stacking two kinds of III-V compound semiconductor layers that contain different materials. According to an embodiment, the materials of the superlattice structure are different from the material of the barrier layer 108c1 or the well layer 108c2. In an embodiment, the superlattice structure may include binary compound semiconductors and ternary compound semiconductors that are alternately stacked, such as GaN and AlGaN. In an embodiment, the superlattice structure may include ternary compound semiconductors and quaternary compound semiconductors that are alternately stacked, such as AlInP and AlGaInP.
As shown in
In an embodiment, the active region 108 optionally includes the first dopant. The first dopant may be an n-type or p-type dopant with respect to the active region 108. In an embodiment, the active region 108 and the first semiconductor structure 104 have the same conductivity type. In an embodiment, the doping concentration of the first dopant in the active region 108 is greater than or equal to 1×1016/cm3. In an embodiment, the doping concentration of the first dopant in the active region 108 is less than 1×1019/cm3. Specifically, the doping concentration of the first dopant in the active region 108 may be in the range of 1×1016/cm3 to 5×1016/cm3, 1×1017/cm3, 5×1017/cm3, 1×1018/cm3 or 5×1018/cm3. The first dopant has a third maximum concentration (C3) in the active region 108, and the third maximum concentration (C3) may be greater than, less than, or equal to the first maximum concentration (C1). In an embodiment, the first dopant is continuously distributed in the active region 108. For example, in a SIMS analysis of the active region 108, the signal of the first dopant can be obtained at each depth position in the active region 108. Specifically, in an embodiment, in the SIMS analysis, the first dopant is distributed between a surface of the second confinement layer 108b away from the semiconductor stack(s) 108c and the interface between the semiconductor stack(s) 108c and the first confinement layer 108a, and is present in each barrier layer 108c1 and each well layer 108c2 of the active region 108. For example, in the active region 108, the first dopant has a doping concentration of not less than 1×1016/cm3 and less than 1×1018/cm3.
In an embodiment, in the semiconductor stack 108c closest to the second confinement layer 108b, the doping concentration of the first dopant may be not less than 1×1016/cm3 and not greater than 1×1018/cm3. In an embodiment, in the semiconductor stack 108c closest to the first confinement layer 108a, the doping concentration of the first dopant may be not less than 1×1016/cm3 and not greater than 1×1017/cm3. In an embodiment, the doping concentration of the first dopant in the semiconductor stack 108c closest to the second confinement layer 108b is greater than or equal to the doping concentration of the first dopant in the semiconductor stack 108c closest to the first confinement layer 108a. In an embodiment, the first dopant is distributed in the first confinement layer 108a, the second confinement layer 108b and the semiconductor stack(s) 108c. In an embodiment, the doping concentration of the first dopant in the second confinement layer 108b is greater than or equal to the doping concentration of the first dopant in the semiconductor stack(s) 108c. In an embodiment, the doping concentration of the first dopant in the semiconductor stack(s) 108c is greater than or equal to the doping concentration of the first dopant in the first confinement layer 108a. In an embodiment, the doping concentration of the first dopant decreases gradually from the second confinement layer 108b to the first confinement layer 108a. Specifically, In an embodiment, the first dopant in the second confinement layer 108b may have a minimum doping concentration 51, the first dopant in the first confinement layer 108a may have a minimum doping concentration S2, and the first dopant in the semiconductor stack(s) 108c may have a minimum doping concentration S3, where S1≥S3≥S2. The minimum doping concentrations S1, S2, and S3 may be the minimum concentrations of the first dopant in the second confinement layer 108b, the first confinement layer 108a, and the semiconductor stack(s) 108c, respectively. For example, when analyzing the concentration curve of the first dopant by SIMS, the minimum doping concentrations mentioned above may correspond to the lowest trough positions of the concentration curve of the first dopant in the second confinement layer 108b, the first confinement layer 108a and the semiconductor stack 108c, respectively, in the SIMS analysis result (in the absence of apparent troughs, the lowest trough positions may refer to minimum detectable concentrations of the first dopant).
The second dopant may also be distributed in the semiconductor stack 108c and/or the first confinement layer 108a. In an embodiment, the first dopant and the second dopant may coexist in the first confinement layer 108a. In an embodiment, the second dopant in the first confinement layer 108a may have a doping concentration of not less than 1×1016/cm3, such as in the range of 5×1016/cm3 to 1×1018/cm3. In an embodiment, the doping concentration of the second dopant in the second semiconductor layer 118 is greater than the doping concentration of the second dopant in the first confinement layer 108a. According to an embodiment, in the active region 108, the concentration of the first dopant gradually increases and the concentration of the second dopant gradually decreases along the direction from the first confinement layer 108a to the second confinement layer 108b. According to an embodiment, when analyzing the distribution of the first dopant and the second dopant in the epitaxial structure 102, the concentration curves of the first dopant and the second dopant have an intersection in the active region 108 as shown in
As shown in
The first electrode 110 and the second electrode 112 provide electrical connections with an external power supply. The materials of the first electrode 110 and the second electrode 112 may be the same or different. For example, the materials of the first electrode 110 and the second electrode 112 may include a metal oxide, a metal or an alloy. The metal oxide may include indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), zinc tin oxide (ZTO), gallium zinc oxide (GZO), indium tungsten oxide (IWO), zinc oxide (ZnO) or indium zinc oxide (IZO). The metal may include germanium (Ge), beryllium (Be), zinc (Zn), gold (Au), platinum (Pt), titanium (Ti), aluminum (Al), nickel (Ni), or copper (Cu). The alloy may include two or more of the above metals, such as germanium gold nickel (GeAuNi), beryllium gold (BeAu), germanium gold (GeAu) or zinc gold (ZnAu).
The main difference between the semiconductor device 20 of this embodiment and the semiconductor device 10 is that the semiconductor device 20 further includes an insulating structure 123, a conductive layer 124, a reflective layer 125 and a bonding structure 128. The insulating structure 123, the conductive layer 124, the reflective layer 125 and the bonding structure 128 are located between the epitaxial structure 102 and the base 100. In this embodiment, the second semiconductor structure 106 further includes a semiconductor contact layer 130. The semiconductor contact layer 130 may be located between the first electrode 110 and the fourth semiconductor layer 122. In this embodiment, the insulating structure 123 is connected to the first semiconductor structure 104, and the first electrode 110 is located on the second semiconductor structure 106 and is electrically connected to the second semiconductor structure 106. The conductive layer 124 covers the insulating structure 123, the reflective layer 125 covers the conductive layer 124, and the bonding structure 128 is located between the base 100 and the reflective layer 125. In this embodiment, the fourth semiconductor layer 122 is located between the semiconductor contact layer 130 and the third semiconductor layer 120 and the upper surface of the fourth semiconductor layer 122 has a roughened structure 122a. The material of the semiconductor contact layer 130 may be different from the material of the fourth semiconductor layer 122. In some embodiments, the material of the semiconductor contact layer 130 includes a binary III-V semiconductor material, such as GaAs or GaP, and may have the same conductivity type as the second semiconductor structure 106.
The insulating structure 123 may be a patterned dielectric layer. For example, the insulating structure 123 includes silicon nitride (SiNx), aluminum oxide (AlOx), silicon oxide (SiOx), magnesium fluoride (MgFx), or a combination thereof. In an embodiment, x=1.5 or 2. In an embodiment, the insulating structure 123 may be a single layer or multiple layers. When the insulating structure 123 is a single layer, it has an insulating refractive index of less than 2; when the insulating structure 123 includes multiple layers, the refractive index of each layer may be less than 2. In an embodiment, the insulating structure 123 may include a Distributed Bragg Reflector (DBR) structure. The DBR structure may include a plurality of first dielectric layers and a plurality of second dielectric layers alternately stacked, and the first dielectric layers and the second dielectric layers have different refractive indices. In an embodiment, the materials of the first dielectric layer and the second dielectric layer include aluminum oxide (Al2O3), silicon dioxide (SiO2), titanium dioxide (TiO2) or tantalum oxide (Nb2O5). As shown in
The conductive layer 124 may include metal or metal oxide. The metal may include silver (Ag), germanium (Ge), gold (Au), nickel (Ni), or a combination thereof. The metal oxide may include indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), zinc tin oxide (ZTO), gallium zinc oxide (GZO), indium tungsten oxide (IWO), zinc oxide (ZnO), indium zinc oxide (IZO), or a combination thereof.
The reflective layer 125 can reflect the light emitted from the active region 108 towards the first electrode 110 to exit the semiconductor device 20. The reflective layer 125 may be conductive and include a semiconductor material, a metal or an alloy. The semiconductor material may include an III-V semiconductor material, such as a binary, ternary or quaternary III-V semiconductor material. The metal may include but not limited to copper (Cu), aluminum (Al), tin (Sn), gold (Au), silver (Ag), lead (Pb), titanium (Ti), nickel (Ni), platinum (Pt) or Tungsten (W). The alloy may include two or more of the above metals. In an embodiment, the reflection layer 125 may include a Distributed Bragg Reflector (DBR) structure. The DBR structure can be formed by alternately stacking two or more semiconductor material layers with different refractive indices, such as AlAs/GaAs, AlGaAs/GaAs or InGaP/GaAs.
The bonding structure 128 connects the base 100 and the reflective layer 125. In an embodiment, the bonding structure 128 may be a single layer or multiple layers (not shown). The bonding structure 128 may be electrically conductive and include a metal oxide, a metal or an alloy. The metal oxide includes but is not limited to indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), zinc tin oxide (ZTO), gallium zinc oxide (GZO), zinc oxide (ZnO), gallium phosphide (GaP), indium cerium oxide (ICO), indium tungsten oxide (IWO), indium titanium oxide (ITiO), indium zinc oxide (IZO), indium gallium oxide (IGO), gallium aluminum zinc oxide (GAZO), or a combination thereof. The metal includes but is not limited to copper (Cu), aluminum (Al), tin (Sn), gold (Au), silver (Ag), lead (Pb), titanium (Ti), nickel (Ni), platinum (Pt) or Tungsten (W). The alloy may include two or more of the above metals.
In the embodiment, the second semiconductor structure 106 may include a third dopant that is different from the first dopant and the second dopant. In an embodiment, the third dopant may be distributed in the semiconductor contact layer 130 and/or the fourth semiconductor layer 122. In an embodiment, the third dopant is continuously distributed in the semiconductor contact layer 130. For example, in a SIMS analysis of the semiconductor contact layer 130, the signal of the third dopant can be obtained at each depth position in the semiconductor contact layer 130. In some embodiments, the semiconductor contact layer 130 and/or the fourth semiconductor layer 122 include both the first dopant and the third dopant. In the semiconductor contact layer 130 and/or the fourth semiconductor layer 122, the doping concentration of the third dopant may be higher than the doping concentration of the first dopant. Specifically, the third dopant may be a group II, group IV or group VI element in the periodic table of elements. In an embodiment, the third dopant is selected from C, Zn, Si, Ge, Sn, Se, Mg or Te. In an embodiment, with respect to the second semiconductor structure 106, the first dopant and the third dopant are of the same conductivity type, and the first dopant and the second dopant are of the different conductivity types. For example, with respect to the second semiconductor structure 106, the first dopant and the third dopant are p-type dopants, and the second dopant is an n-type dopant, or the first dopant and the third dopant are n-type dopants, and the second dopant is a p-type dopant. In an embodiment, the first dopant is continuously distributed from the third semiconductor layer 120 to the first confinement layer 108a. For example, when analyzing the third semiconductor layer 120 to the first confinement layer 108a by SIMS, the signal of the first dopant can be obtained at each depth position from the third semiconductor layer 120 to the first confinement layer 108a.
It should be noted that although in
The main difference between the semiconductor device 30 and the semiconductor device 20 is that the semiconductor device 30 has a patterned first semiconductor layer 116. In this embodiment, the first semiconductor layer 116 does not overlap the structure of the first electrode 110 in the vertical direction. Specifically, the first semiconductor layer 116 includes a plurality of portions 116s separated from each other, and the insulating structure 123 may be located between two adjacent portions 116s, overlapped with each portion 116s in the horizontal direction, and may conformally cover on the side wall 116w of each portion 116s. As shown in
In an embodiment, with respect to the first semiconductor structure 104, the first dopant and the third dopant are of the same conductivity type, the second dopant and the fourth dopant are of the same conductivity type, and the first/third dopants and the second/fourth dopants are of different conductivity types. For example, in an embodiment, the first dopant and the third dopant are n-type dopants, and the second dopant and the fourth dopant are p-type dopants; in another embodiment, the first dopant and the third dopant are p-type dopants, and the second dopant and the fourth dopant are n-type dopants. According to an embodiment, the maximum concentration of the fourth dopant in the first semiconductor layer 116 may be greater than the maximum concentration of the second dopant. Specifically, the fourth dopant in the first semiconductor layer 116 may have a doping concentration of not less than 1×1018/cm3 or not less than 1×1019/cm3, such as in the range of 5×1018/cm3 to 5×1019/cm3. In this embodiment, the doped region 116a does not overlap with the structure of the first electrode 110 in the vertical direction, thereby the current distribution of the semiconductor device 30 during operation can be improved. The detailed descriptions of positions, relative relationships and material of other layers or structures as well as structural variations in this embodiment can be referred to the foregoing embodiments and are not repeatedly described herein.
Specifically,
As shown in
The semiconductor device 60 is located on the carrier 63 and may be the semiconductor device as described in any embodiment of the present disclosure (such as the semiconductor devices 10, 20, 30, 40, 50, 50′ and variations thereof). In the embodiment, the carrier 63 includes a first portion 63a and a second portion 63b, and the semiconductor device 60 is electrically connected to the second portion 63b of the carrier 63 by a bonding wire 65. The material of the bonding wire 65 may include metal, such as gold (Au), silver (Ag), copper (Cu), or aluminum (Al), or may include alloy containing one or more of the above metals. The encapsulating material 68 covers the semiconductor device 60 and protects the semiconductor device 60. Specifically, the encapsulating material 68 may include a resin material, such as an epoxy resin, or a silicone resin. The encapsulating material 68 may further include a plurality of wavelength conversion particles (not shown) to convert a first light emitted by the semiconductor device 60 into a second light. The wavelength of the second light is greater than the wavelength of the first light.
Based on the above, an epitaxial structure, a semiconductor device or a semiconductor component can be provided in the present disclosure. For example, by adjusting dopant concentrations in the epitaxial structure, improved optical-electrical characteristics, such as capacitance or forward voltage, may be provided. Specifically, the epitaxial structure, the semiconductor device or the semiconductor component of the present disclosure can be applied to products in various fields, such as illumination, medical care, display, communication, sensing, or power supply system, for example, can be used in a light fixture, monitor, mobile phone, tablet, an automotive instrument panel, a television, computer, wearable device (such as watch, bracelet or necklace), traffic sign, outdoor display device, or medical device.
It should be realized that each of the embodiments mentioned in the present disclosure is used for describing the present disclosure, but not for limiting the scope of the present disclosure. Any obvious modification or alteration is not departing from the spirit and scope of the present disclosure. Furthermore, embodiments can be combined or substituted under proper condition and are not limited to specific embodiments described above. A connection relationship between a specific component and another component specifically described in an embodiment can also be applied in another embodiment and is within the scope as claimed in the present disclosure.
Number | Date | Country | Kind |
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110131037 | Aug 2021 | TW | national |