The disclosure relates to a substrate structure and a manufacturing method thereof, and in particular relates to a substrate structure having a conductive via and a manufacturing method thereof.
At present, to create high aspect ratio (AR) through glass vias (TGVs) in glass substrates, glass substrates are bonded together through resin material. Subsequently, the through glass vias in two glass substrates are electrically connected through the conductive paste in the resin material. That is, after the two glass substrates are bonded, there is conductive paste between the through glass vias. Alternatively, the thickness of the glass substrate adopted is greater than 200 microns, such as 500 microns, and high aspect ratio through glass vias are formed through laser, etching, hole filling and other processes. It may be seen that it is difficult to produce high aspect ratio through glass vias in glass substrates.
A substrate structure and a manufacturing method thereof are provided in the disclosure, in which the included substrate structure and the manufacturing method thereof may have high aspect ratio through glass vias.
A manufacturing method of a substrate structure of the disclosure includes the following operation. A first substrate including a first core layer and a first conductor that is exposed is provided. A second substrate including a second core layer and a second conductor that is exposed is provided. Conductive nano-wires are formed on the first conductor or the second conductor. The first conductor of the first substrate is aligned with the second conductor of the second substrate, and the conductive nano-wires are located between the first conductor and the second conductor, so that the first substrate and the second substrate are bonded by at least conductive diffusion bonding formed by the conductive nano-wires.
In one embodiment, the first conductor or the second conductor includes the same material as the conductive nano-wires.
In one embodiment, the first conductor or the second conductor includes a copper layer, and the conductive nano-wires are copper nano-wires.
In one embodiment, the copper nano-wires are directly formed on the copper layer.
In one embodiment, the first substrate or the second substrate further includes a polymer, and during the aligning the first conductor of the first substrate with the second conductor of the second substrate, the polymer is further located between the first core layer and the second core layer, so that the first substrate and the second substrate are further bonded through a chain or network structure formed by the polymer.
In one embodiment, during the bonding the first substrate and the second substrate that are separated from each other, the temperature is less than or equal to 200° C.
In one embodiment, the polymer includes a silicone polymer, and the chain or network structure has at least bridging oxygen.
A substrate structure of the disclosure includes a first substrate and a second substrate. The first substrate includes a first core layer and a first conductor. The second substrate includes a second core layer and a second conductor. There is a metal diffusion bonding interface between the first conductor and the second conductor. There is a covalent bonding interface between the first core layer and the second core layer.
In one embodiment, the metal diffusion bonding interface is a copper diffusion bonding interface.
In one embodiment, the covalent bonding interface is a chain or network structure having at least bridging oxygen.
Based on the above, because conductive nano-wires have the characteristics of low melting point and high surface area, the temperature in the manufacturing process operation may be reduced, and problems such as warping and cracking of the chip in an element caused by excessive temperature during the bonding process may be avoided. Therefore, having copper bonding between conductive nano-wires allows for lower heating temperatures to improve the quality of through glass vias with high aspect ratios.
The following examples are described in detail with the accompanying drawings, but the provided examples are not intended to limit the scope of the disclosure. In addition, the drawings are for illustrative purposes only and are not drawn in full scale.
In addition, the terms such as “including”, “having”, etc. used in the text are all open- ended terms, that is, “including but not limited to”.
It should be understood that, although the terms “first”, “second”, “third”, or the like may be used herein to describe various elements, components, regions, layers, and/or portions, these elements, components, regions, and/or portions should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Thus, “a first element,” “component,” “region,” “layer,” or “portion” discussed below may be referred to as a second element, component, region, layer, or portion without departing from the teachings herein.
In the disclosure, wordings used to indicate directions, such as “up,” “down,” “top,” and “bottom,” merely refer to directions in the accompanying drawings. Therefore, the directional terms are used to illustrate rather than limit the disclosure.
In the accompanying drawings, the drawings illustrate the general features of the methods, structures, and/or materials used in the particular embodiments. However, the drawings shall not be interpreted as defining or limiting the scope or nature covered by the embodiments. For example, the relative sizes, thicknesses, and locations of the layers, regions, and/or structures may be reduced or enlarged for clarity.
In the following embodiments, the same or similar elements will be designated by the same or similar reference numerals, and descriptions thereof will be omitted. In addition, the features of different embodiments may be combined with each other when they are not in conflict, and simple equivalent changes and modifications made according to the specification or the claims are still within the scope of the disclosure.
Referring to
In one embodiment, the core substrate 111 may be a glass substrate. In one embodiment, the core substrate 111 may also be a ceramic substrate, a bismaleimide triazine (BT) substrate, an epoxy glass fiber unclad laminate (e.g., FR4) substrate, a polyimide (PI) substrate, an Ajinomoto build-up film (ABF) substrate or a multi-layer circuit board, but the disclosure is not limited thereto. In one embodiment, the thickness T1 of the core substrate 111 may be in a range between about 100 microns and about 400 microns.
In one embodiment, the via 112 may be a penetrating via. In one embodiment, the via 112 may be formed by mechanical drilling, laser drilling, etching, or other suitable methods. In one embodiment, the via 112 may be a through glass via, in which the diameter D1 of the via 112 may be in a range between about 20 microns and about 150 microns.
Referring to
Referring to
In one embodiment, the first conductive layer 114 may be referred to as a seed layer. In one embodiment, the first conductive layer 114 may include copper or/and titanium, but the disclosure is not limited thereto. In one embodiment, the first conductive layer 114 may be formed by using a sputtering process or an electroless plating process, or a sputtering process may be used first and then an electroless plating process may be used to completely cover the sidewalls of the via 112.
Referring to
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It is worth noting that
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In one embodiment, the third conductive layer 117 may be referred to as a seed layer. In one embodiment, the third conductive layer 117 may include copper or/and titanium, but the disclosure is not limited thereto. In one embodiment, the third conductive layer 117 may be formed by using a sputtering process or an electroless plating process, or a sputtering process may be used first and then an electroless plating process may be used so that the sidewalls of the conductive via 116 may be completely covered.
In an embodiment, the third conductive layer 117 may be referred to as a conductive connection layer. That is, the conductive vias 116 that are electrically separated from each other in
Referring to
The material of the patterned mask layer 118 is different from the material of the third conductive layer 117, and its purpose is to make it easier for subsequent conductive nano-wires (the conductive nano-wires 120 shown in
Referring to
In one embodiment, a porous film layer (not marked) may be heat-pressed on the portion of the third conductive layer 117 exposed by the patterned mask layer 118. The aforementioned porous film layer may form a growth template for the conductive nano-wires 120. Then, conductive nano-wires 120 for alignment are formed on the growth template by an appropriate method (e.g., copper electroplating).
In one embodiment, the thickness of the conductive nano-wires 120 (i.e., the alignment height of a majority of each conductive nano-wire 120 for alignment; or, its average) is greater than the thickness of the third conductive layer 117. In this way, it may be suitable for subsequent manufacturing processes. In one embodiment, the thickness of the conductive nano-wire 120 may be adjusted by appropriate means (e.g., the concentration of metal ions in the plating solution, the current of electroplating, the formation time or temperature, etc.).
In the aspect shown in
Referring to
In one embodiment, a portion of the third conductive layer 117 (e.g., a portion of the third conductive layer 117 under the conductive nano-wire 120) may be retained. In one embodiment, during the aforementioned removal process, some of the conductive nano-wires 120 may be removed (e.g., shorter or peripheral conductive nano-wires 120 may be removed); and/or, a portion of the conductive nano-wires 120 may be removed (e.g., a portion of the conductive nano-wires 120 may be removed to make the conductive nano-wires 120 shorter or thinner). That is, compared with the conductive nano-wires 120 in
From the enlarged view, the thickness T3 of the conductive nano-wires 120 may be in a range between about 1 micron and about 50 microns, and the line diameter or line width D2 of the conductive nano-wires 120 may be in a range between about 4 nanometers and about 4 microns.
In addition, before the aforementioned removal process is performed, the thickness of the conductive nano-wire 120 (i.e., the thickness of the conductive nano-wire 120 in
Referring to
In one embodiment, the core substrates 111 in the first substrate 110 and the second substrate 210 are bonded through a sol-gel process. The sol-gel process mainly goes through two stages: a hydrolysis reaction 130 and a condensation reaction 132.
In the hydrolysis reaction 130 stage, the starting reactant may be silane oxide (Si(OR)4, where R is an alkyl functional group; for example, it includes: methyl, ethyl, propyl or isopropyl) (not marked and not limited thereto), which becomes hydroxide after hydrolysis. The chemical reaction formula may be as shown in the following <Reaction Formula 1>. In addition,
Si—OR+H2O→Si—OH+R—OH Reaction Formula 1
In one embodiment, a temperature exceeding 100 degrees Celsius may facilitate the hydrolysis reaction. For example, water molecules produced by hydrolysis reactions may easily become gases and be removed at temperatures exceeding 100 degrees Celsius.
In the condensation reaction 132 stage, after heating, the silane oxide containing hydroxyl groups easily reacts with the hydroxyl groups in other alkoxides to form covalent bonds, and after continuous reactions, polymerizes into a chain or network structure with bridging oxygen. The chemical reaction formula may be as shown in the following <Reaction Formula 2>.
Si—OH+HO—Si→Si—O—Si+H2O <Reaction Formula 2>
In one embodiment, the core substrate 111 of the first substrate 110 and the core substrate 111 of the second substrate 210 are bonded through polymerization of macromolecules. In
Referring to
In one embodiment, the conductive nano-wires 120 of the first substrate 110 and the conductive nano-wires 120 of the second substrate 210 are both copper nano-wires, and Cu-to-Cu diffusion bonding may be achieved between them through heating.
The conductive nano-wire 120 has the characteristics of low melting point and high surface area, so the temperature and pressure during the manufacturing process operation may be reduced, thereby reducing or even avoiding problems such as warping and cracking of the chip in an element caused by excessive temperature and pressure during the bonding process. Taking copper nano-wires as an example, the copper bonding between them may allow for lower heating temperatures (i.e., lower than the melting point of metallic copper), such as no more than about 200 degrees Celsius. In one embodiment, the heating temperature may be in a range between about 100 degrees Celsius and about 200 degrees Celsius, such as about 170 degrees Celsius (170° C.).
Please continue to refer to
In one embodiment, there is a metal diffusion bonding interface 150 between the conductive via 116 of the first substrate 110 and the conductive via 116 of the second substrate 210. In one embodiment, the metal diffusion bonding interface 150 is a copper diffusion bonding interface. In one embodiment, the metal diffusion bonding interface 150 is formed by aligned metal nano-wires (a type of conductive nano-wires, such as copper nano-wires). In one embodiment, although the metal diffusion bonding interface 150 is described as a “bonding interface”, structurally, it may be a thin layer structure or a structure in which nano-wires are interwoven and bonded. In one embodiment, the material of the conductive via 116 is the same as or similar to the material of the metal diffusion bonding interface 150. In one embodiment, when the material of the conductive via 116 and the material of the metal diffusion bonding interface 150 are substantially the same, there may be no obvious interface or layering therebetween (e.g.: between the conductive via 116 of the first substrate 110 and the conductive via 116 of the second substrate 210; and/or, between a certain conductive via 116 and the metal diffusion bonding interface 150).
In one embodiment, there is a covalent bonding interface 140 between the core layer 111 of the first substrate 110 and the core layer 111 of the second substrate 210 through chemical bonding force. In one embodiment, although the covalent bonding interface 140 is described as a “bonding interface”, structurally it may be a thin layer structure.
The structure and manufacturing method of the substrate structure 200 of the second embodiment of the disclosure are similar to the substrate structure 100 of the first embodiment. The only main difference between the two is that an organic resin layer 202 is included on the core layer 111 of at least one of the first substrate 110 and the second substrate 210.
Referring to
In one embodiment, the first substrate 110 and the second substrate 210 of the aforementioned first embodiment may also selectively include conductive layers that are the same as or similar to the fourth conductive layer 201.
Referring to
Referring to
In one embodiment, the core substrates 111 in the first substrate 110 and the second substrate 210 are bonded through a sol-gel process. The sol-gel process mainly goes through two stages: a hydrolysis reaction 130 and a condensation reaction 132.
In the hydrolysis reaction 130 stage, the starting reactant may be silane oxide (Si(OR)4), where R is an alkyl functional group in the organic resin layer 202, and becomes hydroxide after hydrolysis. The chemical reaction formula may be as shown in the aforementioned <Reaction Formula 1>. The molecular structural formula of the hydrolysis reaction 130 is only schematically presented in the left frame (130) of
In the condensation reaction 132 stage, after heating, the silane oxide containing hydroxyl groups easily reacts with the hydroxyl groups in other alkoxides to form covalent bonds, and after continuous reactions, polymerizes into a chain or network structure with bridging oxygen. The chemical reaction formula may be as shown in the aforementioned <Reaction Formula 2>. The core substrate 111 of the first substrate 110 and the core substrate 111 of the second substrate 210 are bonded through polymerization of macromolecules. In the right frame (132) of
Referring to
Please continue to refer to
In addition, after the conductive nano-wires 120 are formed, the fourth conductive layer 201 may be correspondingly removed in appropriate steps.
Referring to
Therefore, the organic resin layer 202 and the conductive nano-wires 120 on the core layer 111 of the first substrate 110 are bonded to the organic resin layer 202 and the conductive nano-wires 120 on the core layer 111 of the second substrate 210 to form the substrate structure 200 of the second embodiment.
Please continue to refer to
In the aforementioned embodiment, conductive nano-wires for alignment are formed on a conductor (e.g., conductive via 116). Moreover, conductors for alignment in different substrates (e.g., the first substrate 110 and the second substrate 210) may be bonded by the conductive nano-wires included therein. Moreover, insulators for alignment in different substrates (e.g., the first substrate 110 and the second substrate 210) may form a chain or network structure with bridging atoms (e.g., bridging oxygen) through covalent bonds, so that insulators for alignment in different substrates are bonded. Because the aforementioned two types of bonding (i.e., the bonding of conductors and insulators) may form an effective bond (e.g., atomic bridges may be formed; and, metal-to-metal diffusion bonding) at low heating temperatures (e.g., lower than the melting point of metallic copper) due to the materials and/or structures for alignment (e.g., materials with silicone and siloxane-based material; and, copper nano-wires), therefore, the possibility of thermal damage and/or thermal warping to the elements due to heating during the bonding process may be reduced. In this way, the quality and effect of the bonding may be improved.
In the aforementioned embodiments, the conductive layer may be a single layer or a multi-layer structure. If the conductive layer is a multi-layer structure, there may be no insulating material or dielectric material in between the multi-layer structure. In addition, in terms of structure, if it is a conductive layer of a multi-layer structure, even if the multi-layer structure is formed by different manufacturing processes, it may (but is not limited to) be represented by the same terms and/or reference numerals.
In the aforementioned embodiments, the insulating layer may be a single layer or a multi- layer structure. If it is an insulating layer with a multi-layer structure, there may be no conductive material in between the multi-layer structure. In addition, in terms of structure, if it is an insulating layer of a multi-layer structure, even if the multi-layer structure is formed by different manufacturing processes, it may (but is not limited to) be represented by the same terms and/or reference numerals.
In the aforementioned embodiments, one conductor and another conductor may be electrically connected to each other through the aligned conductive elements (e.g., conductive vias and wires). That is, unless otherwise stated or implied, even if one conductor and another conductor are not shown in the diagrams, the aforementioned one conductor and the aforementioned another conductor may still be electrically connected to each other through conductive elements that are not illustrated or not shown in cross-section in the diagrams.
| Number | Date | Country | Kind |
|---|---|---|---|
| 113116076 | Apr 2024 | TW | national |
| 113143769 | Nov 2024 | TW | national |
This application is a continuation-in-part application of and claims the priority benefit of U.S. application Ser. No. 18/677,924, filed on May 30, 2024, now pending. The prior U.S. application Ser. No. 18/677,924 claims the priority benefits of U.S. provisional application Ser. No. 63/623,823, filed on Jan. 23, 2024, and Taiwan application serial no. 113116076, filed on Apr. 30, 2024. This application also claims the priority benefit of U.S. provisional application Ser. No. 63/666,227, filed on Jun. 30, 2024, and Taiwan application serial no. 113143769, filed on Nov. 14, 2024. The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of this specification.
| Number | Date | Country | |
|---|---|---|---|
| 63623823 | Jan 2024 | US | |
| 63666227 | Jun 2024 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 18677924 | May 2024 | US |
| Child | 19023397 | US |