Electronic component

Abstract

This electronic component includes: a substrate having a main surface; an insulating layer disposed on the main surface of the base material and having an opening; a conductive layer formed in the opening of the insulating layer; and a barrier layer covering the conductive layer; wherein at least the shape of the outer surface of the barrier layer is provided with a mountain part protruding upwards.

Description

TECHNICAL FIELD

[0001] The present application relates to an electronic component. BACKGROUND

[0002] As an electronic component, an electronic component described in Patent Literature 1 is known. The electronic component includes a substrate having a main surface, an insulating layer disposed on the main surface of the substrate and having an opening portion, a conductive layer formed on the opening portion of the insulating layer, and a barrier layer covering the conductive layer.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: International Publication No. 2022 / 244473 SUMMARY

[0006] [PROBLEMS TO BE SOLVED BY THE INVENTION]

[0007] A recess is formed on the upper surface of the electrode pad of the above-described electronic component. At the position of the recess, a seam can be generated in the barrier layer. In addition, when an etching solution is used in the manufacturing process of the electronic component, a phenomenon in which the etching solution remains in the recess after the etching process occurs. In this case, the conductive layer can be corroded by the etching solution passing through the above-described seam. Therefore, it is required to suppress such corrosion, thereby improving the reliability of the electronic component.

[0008] An object of the present application is to provide an electronic component capable of improving the reliability.

[0009] [MEANS FOR SOLVING THE PROBLEMS]

[0010] The electronic component of the present application includes a substrate having a main surface, an insulating layer disposed on the main surface of the substrate and having an opening portion, a conductive layer formed on the opening portion of the insulating layer, and a barrier layer covering the conductive layer, wherein at least the shape of the outer surface of the barrier layer has one upwardly protruding mountain portion.

[0011] In the electronic component of the present application, the shape of the outer surface of the barrier layer covering the conductive layer has one upwardly protruding mountain portion. According to this shape, it is possible to suppress the formation of a recess on the outer surface of the barrier layer. Therefore, it is possible to suppress the stagnation of the etching solution used in the etching process on the outer surface of the barrier layer. Therefore, even in the case where the etching process is used, it is possible to suppress the corrosion caused by the infiltration of the etching solution into the conductive layer. The reliability of the electronic component can be improved by the above-described means.

[0012] The barrier layer can extend over the insulating layer. In this case, it is possible to suppress the corrosion of the conductive layer present on the insulating layer by the etching solution.

[0013] The electronic component of the present application can further have a thin film formed on the barrier layer. In this case, even if a defect such as a hole exists at the barrier layer, the thin film can cover the defect. Therefore, the corrosion of the conductive layer caused by the etching liquid can be more reliably suppressed.

[0014] The barrier layer contains at least any one of Ni, Ta, Ti, W, Mo, Cr, Zn, In, Nb, Sn, and C. In this case, the corrosion resistance of the barrier layer to the etching liquid can be improved. Therefore, the corrosion of the conductive layer caused by the defect due to the corrosion of the barrier layer can be suppressed.

[0015] The thickness of the barrier layer can be 100 nm or more. In this case, the barrier layer can sufficiently cover the conductive layer. Therefore, the corrosion of the conductive layer by the etching liquid can be more reliably suppressed.

[0016] The insulating layer can contain at least one of silicon oxide, silicon nitride, silicon oxynitride, epoxy resin, and polyimide. In this case, the corrosion resistance of the insulating layer itself to the etching liquid can be improved. As a result, the corrosion of the conductive layer caused by the defect due to the corrosion of the insulating layer can be suppressed.

[0017] The substrate can also contain GaN. As the etching liquid, a chemical liquid containing H2O2 is used in many cases. The H2O2 can oxidize GaN to form Ga2O3. Therefore, when GaN is used as the substrate, if the conductive layer is corroded, the H2O2 permeates into the substrate, Ga2O3 can be formed between GaN and the conductive layer, and thus the function as a semiconductor can be lost. Therefore, in the present application, when GaN is contained in the substrate, the effect of the present application can be more remarkably exhibited.

[0018] [Effects of Invention]

[0019] According to the present application, an electronic component capable of improving reliability can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a schematic cross-sectional view of an electronic component representing an embodiment of the present application.

[0021] Figure 2 is a schematic cross-sectional view of an electronic component representing a comparative example.

[0022] Figure 3 is a schematic cross-sectional view of an electronic component representing a modified example.

[0023] Figure 4 is a schematic cross-sectional view of an electronic component representing a modified example.

[0024] Figure 5 is a schematic cross-sectional view of an electronic component representing a modified example.

[0025] Figure 6 This is a schematic cross-sectional view of an electronic component representing a modified example. Detailed Implementation

[0026] Reference Figure 1 The structure of the electronic component in the embodiment will be described. The electronic component 1 in the embodiment includes a substrate 10, an insulating layer 20, and an electrode pad 30. An example of the electronic component 1 is a semiconductor element, such as an LED element or a semiconductor laser element.

[0027] The substrate 10 is a flat plate. The substrate 10 has a flat main surface 10a. The substrate 10 may contain GaN. Alternatively, the substrate 10 may also contain GaAs, GaP, AlGaInP, InGaN, Si, etc.

[0028] An insulating layer 20 is disposed on the main surface 10a of the substrate 10 in such a way as to cover the main surface 10a. The insulating layer 20 is a so-called passivation film. The insulating layer 20 has a flat main surface 20a. The insulating layer 20 is composed of an oxide or nitride containing at least one element selected from Si, Al, Zr, Mg, Ta, Ti, and Y, or is composed of a resin. For example, the insulating layer 20 may contain at least one of silicon oxide, silicon nitride, silicon oxynitride, epoxy resin, and polyimide. The thickness of the insulating layer 20 is not particularly limited and may be 100 nm or more and 3000 nm or less.

[0029] An opening 21 is provided in the insulating layer 20. When viewed from a direction orthogonal to the main surface 10a, the opening 21 has an arbitrary shape (e.g., a circle, a polygon, etc.). The opening 21 of the insulating layer 20 has an inner peripheral surface 21a extending vertically between the main surface 10a of the substrate 10 and the main surface 20a of the insulating layer 20. In this embodiment, the inner peripheral surface 21a extends substantially perpendicular to the main surface 10a.

[0030] The electrode pad 30 is made of a metallic material. The electrode pad 30 is a thick-film electrode disposed near the opening 21 of the insulating layer 20 and extending along the normal direction of the main surface of the substrate 10. The electrode pad 30 includes a conductive layer 31 and a barrier layer 32. The conductive layer 31 is the portion located on the upper side of the insulating layer 20. When viewed from a direction orthogonal to the main surface 10a, the electrode pad 30 has an arbitrary shape (e.g., circular, polygonal, etc.).

[0031] The conductive layer 31 is formed on the opening 21 of the insulating layer 20 in such a way that it covers the opening 21. The conductive layer 31 can be formed, for example, by sputtering Cu. More specifically, the conductive layer 31 integrally covers the edge of the opening 21 on the main surface 20a of the insulating layer 20, the main surface 10a of the substrate 10 exposed from the opening 21, and the inner peripheral surface 21a of the opening 21.

[0032] The barrier layer 32 is a layer covering the conductive layer 31. The barrier layer 32 covers the entire area of ​​the outer surface 31a of the conductive layer 31. As described above, the conductive layer 31 covers the edge of the opening 21 of the insulating layer 20. Therefore, the barrier layer 32 also covers the edge of the opening 21 of the insulating layer 20. Thus, the barrier layer 32 extends above the insulating layer 20. The barrier layer 32 may contain at least one of Ni, Ta, Ti, W, Mo, Cr, Zn, In, Nb, Sn, and C. The thickness of the barrier layer 32 may be 100 nm or more, or 300 nm or more. The thickness of the barrier layer 32 may be less than 3000 nm, or less than 1000 nm.

[0033] Next, the cross-sectional shape of the electrode pad 30 will be described. The electrode pad 30 has a shape that rises upward from the substrate 10. The electrode pad 30 has: edge portions 40A and 40B; raised portions 41A and 41B; and a body portion 42. The edge portion 40 is the portion that extends along the main surface 20a near the edge of the opening 21 of the main surface 20a of the insulating layer 20. The thickness of the edge portion 40 is thinner than that of the body portion 42. The raised portion 41 is the portion that rises upward from the edge portion 40. The body portion 42 is the portion that is formed thicker at the center of the electrode pad 30. The thickness T of the conductive layer 31 in the body portion 42 can be 100 nm or more, and can be 5000 nm or less.

[0034] In this embodiment, the outer surface 31a of the conductive layer 31 and the outer surface 32a of the barrier layer 32 have substantially the same shape and are in a generally parallel relationship. The outer surface of the electrode pad 30 corresponds to the outer surface 32a of the outermost barrier layer 32.

[0035] In the cross-sectional view, the main body 42 has a pair of raised portions 41A and 41B on the left and right sides, and a pair of edge portions 40A and 40B on the right and left sides. The portions of the outer surfaces 31a and 32a that form an angle of 45° or more with respect to the main surface 10a can be regarded as the raised portions 41A and 41B. However, if the electrode pad 30 has a gently curved shape as a whole, the portions corresponding to the raised portions 41A and 41B can be omitted.

[0036] The outer surfaces 31a and 32a of the main body 42 extend in the direction extending along the main surface 10a between the upper ends of the upright portions 41A and 41B. Additionally, corner portions 43A and 43B are formed at the locations where the upright portions 41A and 41B connect to the main body 42. However, as... Figure 1 As shown, it is not necessary to explicitly form the corner portions 43A and 43B; it is sufficient that the upright portions 41A and 41B are connected to the main body portion 42. In this embodiment, the outer surfaces 31a and 32a of the main body portion 42 have a shape that protrudes upward from the outer peripheral end toward the inner peripheral side. Therefore, the outer surface 32a of the barrier layer 32 has an upwardly protruding hill 50.

[0037] The outer surfaces 31a and 32a of the mountain portion 50 are depicted as arcs curving upwards between corner portions 43A and 43B. The surface of the mountain portion 50 is referred to as the curved surface 51. When the mountain portion 50 is depicted as an arc, the radius of curvature of the outermost outer surface 32a of the mountain portion 50 can be 4.5 μm or more. The lateral dimension W of the mountain portion 50 can be 2 μm or more, and can be 10 μm or less. In this embodiment, the lateral dimension W of the mountain portion 50 is the lateral dimension between corner portions 43A and 43B. Additionally, sometimes minute irregularities due to surface roughness or slightly protruding small convex portions due to manufacturing errors may be formed on the outer surface 32a. However, these small convex portions do not correspond to the mountain portion as described in this specification. Furthermore, for corner portions 43A and 43B, the outer peripheral portions (i.e., the raised portions 41A and 41B) extend downwards away from corner portions 43A and 43B. However, the inner peripheral portion (i.e., the body portion 42) does not extend downwards away from the corner portions 43A and 43B. Therefore, the corner portions 43A and 43B do not correspond to the mountain portion in this specification.

[0038] There are no particular limitations on the method for forming the hill 50 of the electronic component 1. For example, as a method for forming the conductive layer 31, the following method can be used: for the opening 21 of the insulating layer 20, the opening size of the lift-off resist is adjusted, and the resist is removed after sputtering. Alternatively, the conductive layer 31 can also be formed using the deposited film. The hill 50 can also be formed using these methods.

[0039] Furthermore, there are no particular limitations on the method for forming the barrier layer 32 in a manner that extends to the insulating layer 20. For example, as a method for forming the barrier layer 32, the following approach can be adopted: widen the opening size of the stripping resist opening and perform stripping after sputtering. In this case, by making the opening size wider than that of the conductive layer 31, the barrier layer 32 can be extended to the insulating layer 20. Alternatively, the barrier layer 32 can also be formed using a deposited film.

[0040] The function and effects of the electronic component 1 in this embodiment will be explained.

[0041] First, refer to Figure 2 The electronic component 100 of the comparative example will be described. For example... Figure 2 As shown, a recess 150 is formed on the upper surface of the electrode pad 130 of the comparative example electronic component 100. At the location of this recess 150, a gap X may be formed in the barrier layer 132. Furthermore, when an etching solution is used in the fabrication process of the electronic component, etching solution residue may remain in the recess 150 after the etching process. In this case, the conductive layer 131 may be corroded as the etching solution passes through the aforementioned gap X.

[0042] In contrast, in the electronic component 1 of this embodiment, the outer surface 32a of the barrier layer 32 covering the conductive layer 31 has an upwardly protruding hill 50. This shape suppresses the formation of recesses on the outer surface 32a of the barrier layer 32. Therefore, it prevents the etching solution used in the etching process from remaining on the outer surface 32a of the barrier layer 32. Thus, even when using an etching process, corrosion caused by the etching solution penetrating into the conductive layer 31 can be suppressed. This structure improves the reliability of the electronic component 1.

[0043] The barrier layer 32 can extend onto the insulating layer 20. In this case, the conductive layer 31 present on the insulating layer 20 can be prevented from being corroded by the etching solution.

[0044] The barrier layer 32 may contain at least one of Ni, Ta, Ti, W, Mo, Cr, Zn, In, Nb, Sn, and C. In this case, the corrosion resistance of the barrier layer 32 to the etching solution can be improved. Therefore, it is possible to suppress the corrosion of the conductive layer 31 due to defects caused by the corrosion of the barrier layer 32.

[0045] The thickness of the barrier layer 32 can be 100 nm or more. In this case, the barrier layer 32 can fully cover the conductive layer 31. Therefore, the corrosion of the conductive layer 31 by the etchant can be more effectively suppressed.

[0046] The insulating layer 20 may comprise at least one of silicon oxide, silicon nitride, silicon oxynitride, epoxy resin, and polyimide. In this case, the corrosion resistance of the insulating layer 20 itself to the etching solution can be improved. As a result, defects caused by the corrosion of the insulating layer 20 that lead to corrosion of the conductive layer 31 can be suppressed.

[0047] The substrate 10 may contain GaN. As the etching solution, a solution containing H2O2 is typically used. This H2O2 may oxidize GaN to form Ga2O3. Therefore, when GaN is used as the substrate 10, if the conductive layer 31 is etched, H2O2 penetrates into the substrate 10, forming Ga2O3 between the GaN and the conductive layer 31, potentially rendering it unable to function as a semiconductor. Therefore, for the structure of the electronic component 1 in this embodiment, including GaN in the substrate 10 makes the effects of the present invention more significant.

[0048] The present invention is not limited to the embodiments described above.

[0049] For example, it can be adopted Figure 3 The structure shown. Figure 3 The illustrated electronic component 1 further includes a thin film 33 formed on the barrier layer 32. The thin film 33 covers the entire barrier layer 32. There are no particular limitations on the material of the thin film 33; for example, Au, Sn, Pd, etc., can be used. There are also no particular limitations on the thickness of the thin film 33; it can be 10 nm or more and 300 nm or less. In this case, even if defects such as pores exist in the barrier layer 32, the thin film 33 can cover these defects. Therefore, corrosion of the conductive layer 31 caused by the etching solution can be suppressed more reliably.

[0050] The shape or position of the hill 50 is not limited to the above-described embodiment. For example, it can be adopted... Figure 4 The structure shown. Figure 4 In the illustrated electronic component 1, a hill 50 is formed in a portion of the body portion 42 by a protrusion 60 that protrudes further upward than the curved surface 51 described above. The protrusion 60 is formed by extending the upper end of the upright portion 41A to a position higher than the other upright portions 41B, and drawing an arc with a radius of curvature smaller than the arc of the curved surface 51. The curved surface 51 of the body portion 42 does not have any portion protruding upward except for the protrusion 60. Therefore, the outer surface 32a of the barrier layer 32 has a hill 50.

[0051] Alternatively, it can be used Figure 5 The structure shown. In Figure 5 In the electronic component 1 shown, the main body 42 is bent significantly. Therefore, corner portions 43A and 43B are not formed between the raised portions 41A and 41B and the main body 42 (see reference). Figure 1The main body 42 is formed in such a way that a continuous arc is drawn from the raised parts 41A and 41B. By making the main body 42 as a whole bend significantly in a way that protrudes upward, the outer surface 32a of the barrier layer 32 has a mountain 50.

[0052] It can be adopted Figure 6 The structure shown. Figure 6 The electronic component 1 shown is configured in such a way that it enables... Figure 4 The protrusion 60 shown is curved to a greater extent, forming a structure in which the upright portion 41B and the main body portion 42 are curved without the corner portion 43B. The main body portion 42 does not have any portion that protrudes upward except for the protrusion 60. Therefore, the outer surface 32a of the barrier layer 32 has a hill 50.

[0053] Furthermore, the shapes of the barrier layer and the conductive layer do not necessarily have to be the same. For example, the barrier layer only needs to have one mountain, while the conductive layer can have two or more mountains.

[0054] [Form 1]

[0055] An electronic component, wherein,

[0056] Include:

[0057] The substrate has a main surface;

[0058] An insulating layer disposed on the main surface of the substrate and having an opening;

[0059] A conductive layer is formed at the opening of the insulating layer; and

[0060] A barrier layer that covers the aforementioned conductive layer;

[0061] Furthermore, at least the outer surface of the aforementioned barrier layer has an upwardly protruding hillside.

[0062] [Form 2]

[0063] As described in aspect 1, the electronic component wherein the barrier layer extends over the insulating layer.

[0064] [Form 3]

[0065] The electronic component as described in aspect 1 or 2 further comprises a thin film formed on the aforementioned barrier layer.

[0066] [Form 4]

[0067] The electronic component described in any one of forms 1 to 3, wherein the barrier layer comprises at least one of Ni, Ta, Ti, W, Mo, Cr, Zn, In, Nb, Sn and C.

[0068] [Form 5]

[0069] The electronic component described in any of forms 1 to 4, wherein the thickness of the aforementioned barrier layer is 100 nm or more.

[0070] [Form 6]

[0071] The electronic component described in any of forms 1 to 5, wherein the insulating layer comprises at least one of silicon oxide, silicon nitride, silicon oxynitride, epoxy resin, and polyimide.

[0072] [Form 7]

[0073] The electronic component described in any of forms 1 to 6, wherein the substrate comprises GaN.

[0074] [Symbol Explanation]

[0075] 1: Electronic components

[0076] 10: Substrate

[0077] 20: Insulation layer

[0078] 31: Conductive layer

[0079] 32: Barrier layer

[0080] 50: Yamabe.

Claims

1. An electronic component, wherein, Include: The substrate has a main surface; An insulating layer disposed on the main surface of the substrate and having an opening; A conductive layer formed at the opening of the insulating layer; and A barrier layer that covers the conductive layer; At least the outer surface of the barrier layer has an upwardly protruding hill.

2. The electronic component according to claim 1, wherein, The barrier layer extends over the insulating layer.

3. The electronic component according to claim 1, wherein, It further comprises a thin film formed on the barrier layer.

4. The electronic component according to claim 1, wherein, The barrier layer comprises at least one of Ni, Ta, Ti, W, Mo, Cr, Zn, In, Nb, Sn, and C.

5. The electronic component according to claim 1, wherein, The thickness of the barrier layer is 100 nm or more.

6. The electronic component according to claim 1, wherein, The insulating layer comprises at least one of silicon oxide, silicon nitride, silicon oxynitride, epoxy resin, and polyimide.

7. The electronic component according to claim 1, wherein, The substrate contains GaN.

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