Electronic component

Abstract

To provide an electronic component capable of improving the reliability thereof.SOLUTION: In an electronic component 1, a shape of an external surface 32a of a barrier layer 32 that covers a conductive layer 31 has a peak 50 that protrudes upward. Such a shape can suppress the formation of a recess on the external surface 32a of the barrier layer 32. Therefor, an accumulation, of an etching solution used in an etching process, on the external surface 32a of the barrier layer 32 can be suppressed. Consequently, even when an etching process is used, corrosion due to permeation of an etching solution into the conductive layer 31 can be suppressed. Thus, the improvement of the electronic component 1 can be improved.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to electronic components. [Background technology]

[0002] A known electronic component is described in Patent Document 1. This electronic component includes a substrate having a main surface, an insulating layer disposed on the main surface of the substrate and having an opening, a conductive layer formed in the opening of the insulating layer, and a barrier layer covering the conductive layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2022 / 244473 Summary of the Invention [Problem to be solved by the invention]

[0004] A recess is formed on the upper surface of the electrode pad of the electronic component. A seam may occur in the barrier layer at the recess. In addition, when an etching solution is used in the electronic component manufacturing process, the etching solution may remain in the recess after the etching process. In this case, the etching solution may pass through the seam and corrode the conductive layer. Therefore, there is a need to suppress such corrosion and improve the reliability of the electronic component.

[0005] An object of the present invention is to provide an electronic component that can improve reliability. [Means for solving the problem]

[0006] The electronic component of the present invention includes a substrate having a main surface, an insulating layer disposed on the main surface of the substrate and having an opening, a conductive layer formed in the opening of the insulating layer, and a barrier layer covering the conductive layer, and at least the outer surface of the barrier layer is shaped to have one upwardly protruding ridge.

[0007] In the electronic component according to the present invention, the shape of the outer surface of the barrier layer covering the conductive layer has one ridge that protrudes upward. This shape can prevent recesses from being formed on the outer surface of the barrier layer. This can prevent the etching solution used in the etching process from accumulating on the outer surface of the barrier layer. This can prevent corrosion caused by the etching solution penetrating into the conductive layer even when the etching process is used. As a result, the reliability of the electronic component can be improved.

[0008] The barrier layer may extend onto the insulating layer, in which case the conductive layer present on the insulating layer can be prevented from being corroded by the etching solution.

[0009] The conductive layer may further include a thin film formed on the barrier layer. In this case, even if a defect such as a hole exists in the barrier layer, the thin film can cover the defect. Therefore, corrosion of the conductive layer by the etching solution can be more reliably suppressed.

[0010] The barrier layer is made of a material containing 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 against the etching solution can be improved. Therefore, the conductive layer can be prevented from being corroded due to damage caused by the corrosion of the barrier layer.

[0011] The thickness of the barrier layer may be 100 nm or more, in which case the barrier layer can sufficiently cover the conductive layer, and therefore the conductive layer can be more reliably prevented from being corroded by the etching solution.

[0012] The insulating layer may 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 against the etching solution can be improved. As a result, the conductive layer can be prevented from being corroded due to defects caused by the corrosion of the insulating layer.

[0013] The substrate may contain GaN. A chemical solution containing H2O2 is often used as an etching solution. This H2O2 may oxidize GaN and form Ga2O3. Therefore, when GaN is used as the substrate, if the conductive layer is corroded and H2O2 penetrates into the substrate, Ga2O3 may be formed between the GaN and the conductive layer, and the substrate may no longer function as a semiconductor. Therefore, the effect of the present invention can be more pronounced when the substrate contains GaN. Effect of the Invention

[0014] According to the present invention, it is possible to provide an electronic component that can improve reliability. [Brief description of the drawings]

[0015] [Figure 1] 1 is a schematic cross-sectional view showing an electronic component according to an embodiment of the present invention. [Diagram 2] FIG. 11 is a schematic cross-sectional view showing an electronic component according to a comparative example. [Diagram 3] FIG. 11 is a schematic cross-sectional view showing an electronic component according to a modified example. [Figure 4] FIG. 11 is a schematic cross-sectional view showing an electronic component according to a modified example. [Diagram 5] FIG. 11 is a schematic cross-sectional view showing an electronic component according to a modified example. [Figure 6] FIG. 11 is a schematic cross-sectional view showing an electronic component according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The configuration of an electronic component according to an embodiment will be described with reference to Fig. 1. An electronic component 1 according to an embodiment includes a substrate 10, an insulating layer 20, and an electrode pad 30. As an example, the electronic component 1 is a semiconductor element, such as an LED element or a semiconductor laser element.

[0017] The substrate 10 is a flat plate-shaped member. The substrate 10 has a flat main surface 10a. The substrate 10 may include GaN. Alternatively, the substrate 10 may include GaAs, GaP, AlGaInP, InGaN, Si, or the like.

[0018] The insulating layer 20 is disposed on the main surface 10a of the substrate 10 so as to cover the main surface 10a. The insulating layer 20 is a so-called passive film (passivation film). The insulating layer 20 has a flat main surface 20a. The insulating layer 20 is made of an oxide or nitride containing at least one of the elements Si, Al, Zr, Mg, Ta, Ti, and Y, or 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, but may be 100 nm or more and 3000 nm or less.

[0019] An opening 21 is provided in the insulating layer 20. The opening 21 has any shape (e.g., circular, polygonal, etc.) when viewed from a direction perpendicular to the main surface 10a. The opening 21 in the insulating layer 20 has an inner circumferential surface 21a extending in the up-down direction between the main surface 10a of the base material 10 and the main surface 20a of the insulating layer 20. In this embodiment, the inner circumferential surface 21a extends approximately perpendicular to the main surface 10a.

[0020] The electrode pad 30 is made of a metal material. The electrode pad 30 is a thick film electrode provided near the opening 21 of the insulating layer 20 and extending in the normal direction of the main surface of the base material 10. The electrode pad 30 includes a conductive layer 31 and a barrier layer 32. The conductive layer 31 is a portion located on the upper side of the insulating layer 20. The electrode pad 30 has any shape (e.g., circular, polygonal, etc.) when viewed from a direction perpendicular to the main surface 10a.

[0021] The conductive layer 31 is formed in the opening 21 of the insulating layer 20 so as to cover the opening 21. The conductive layer 31 can be formed by, for example, 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 base material 10 exposed from the opening 21, and the inner circumferential surface 21a of the opening 21.

[0022] The barrier layer 32 is a layer that covers the conductive layer 31. The barrier layer 32 covers the entire 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. Therefore, the barrier layer 32 extends onto the insulating layer 20. The barrier layer 32 may be a material containing 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 may be 300 nm or more. The thickness of the barrier layer 32 may be 3000 nm or less, or may be 1000 nm or less.

[0023] Next, the cross-sectional shape of the electrode pad 30 will be described. The electrode pad 30 has a shape rising upward from the substrate 10. The electrode pad 30 has edge portions 40A, 40B, rising portions 41A, 41B, and a main body portion 42. The edge portion 40 is a portion that extends along the main surface 20a of the insulating layer 20 near the edge of the opening 21. The edge portion 40 is thinner than the main body portion 42. The rising portion 41 is a portion that rises upward from the edge portion 40. The main body portion 42 is a portion that is formed thick at the center position of the electrode pad 30. The thickness T of the conductive layer 31 in the main body portion 42 may be 100 nm or more and may be 5000 nm or less.

[0024] In this embodiment, the outer surface 31a of the conductive layer 31 and the outer surface 32a of the barrier layer 32 have the same shape and are in a substantially parallel relationship. The outer surface of the electrode pad 30 corresponds to the outer surface 32a of the barrier layer 32, which is the outermost layer.

[0025] In a cross-sectional view, the main body 42 has a pair of rising portions 41A, 41B and a pair of edge portions 40A, 40B on the left and right sides. The rising portions 41A, 41B may be regarded as portions where the outer surfaces 31a, 32a form an angle of 45° or more with respect to the main surface 10a. However, if the electrode pad 30 has a gently curved shape as a whole, the portions corresponding to the rising portions 41A, 41B may be omitted.

[0026] The outer surfaces 31a, 32a of the main body 42 extend along the direction in which the main surface 10a extends between the upper end of the rising portion 41A and the upper end of the rising portion 41B. In addition, corners 43A, 43B are formed at the points where the rising portions 41A, 41B and the main body 42 are connected. However, as shown in FIG. 1, it is not necessary to clearly form the corners 43A, 43B, as long as the rising portions 41A, 41B and the main body 42 are connected. In this embodiment, the outer surfaces 31a, 32a of the main body 42 have a shape that protrudes upward from the end on the outer periphery side toward the inner periphery side. As a result, the shape of the outer surface 32a of the barrier layer 32 has one ridge portion 50 that protrudes upward. The shape of the outer surface 32a of the barrier layer 32 has one ridge portion 50 that protrudes upward.

[0027] The outer surfaces 31a, 32a of the peak portion 50 form a curved arc between the corners 43A and 43B so as to be convex upward. The surface of the peak portion 50 is a curved surface 51. When the peak portion 50 is formed by an arc, the radius of curvature of the outermost outer surface 32a of the peak portion 50 may be 4.5 μm or more. The horizontal dimension W of the peak portion 50 may be 2 μm or more and 10 μm or less. In this embodiment, the horizontal dimension W of the peak portion 50 is the horizontal dimension between the corners 43A and 43B. Note that the outer surface 32a may have minute irregularities formed due to surface roughness, or minute protrusions that protrude slightly due to manufacturing errors, etc. However, these minute protrusions do not fall under the peak portion of this specification. In addition, the outer peripheral portion of the corners 43A and 43B (i.e., the rising portions 41A and 41B) slopes downward as it moves away from the corners 43A and 43B, but the inner peripheral portion (i.e., the main body portion 42) does not slope downward as it moves away from the corners 43A and 43B. Therefore, the corners 43A and 43B do not correspond to the peaks in this specification.

[0028] The method for forming the ridges 50 of the electronic component 1 is not particularly limited. For example, the conductive layer 31 may be formed by adjusting the opening size of the openings in the lift-off resist relative to the openings 21 in the insulating layer 20, and then performing lift-off after sputtering film formation. The conductive layer 31 may also be formed by film formation by plating. The ridges 50 may be formed by these methods.

[0029] Furthermore, the method for forming the barrier layer 32 so as to extend to the insulating layer 20 is not particularly limited. For example, the method for forming the barrier layer 32 may be a method in which the opening size of the opening of the lift-off resist is widened and lift-off is performed 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. Moreover, the barrier layer 32 may be formed by film formation by plating.

[0030] The operation and effect of the electronic component 1 according to this embodiment will be described.

[0031] First, an electronic component 100 according to a comparative example will be described with reference to Fig. 2. As shown in Fig. 2, a recess 150 is formed on the upper surface of an electrode pad 130 of the electronic component 100 according to the comparative example. At the location of the recess 150, a seam X may be generated in the barrier layer 132. Furthermore, when an etching solution is used in the electronic component manufacturing process, a phenomenon occurs in which the etching solution remains in the recess 150 after the etching process. In this case, the etching solution may pass through the above-mentioned seam X and corrode the conductive layer 131.

[0032] In contrast, in electronic component 1 according to this embodiment, outer surface 32a of barrier layer 32 covering conductive layer 31 has a shape that has one ridge 50 that protrudes upward. This shape can prevent recesses from being formed on outer surface 32a of barrier layer 32. This can prevent the etching solution used in the etching process from accumulating on outer surface 32a of barrier layer 32. This can prevent corrosion caused by the etching solution penetrating into conductive layer 31 even when an etching process is used. As a result, the reliability of electronic component 1 can be improved.

[0033] The barrier layer 32 may 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.

[0034] The barrier layer 32 may be made of a material containing 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 against the etching solution can be improved. Therefore, the conductive layer 31 can be prevented from being corroded due to damage caused by the corrosion of the barrier layer 32.

[0035] The thickness of the barrier layer 32 may be 100 nm or more. In this case, the barrier layer 32 can sufficiently cover the conductive layer 31. Therefore, corrosion of the conductive layer 31 by the etching solution can be more reliably suppressed.

[0036] The insulating layer 20 may 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 20 itself against the etching solution can be improved. As a result, the conductive layer 31 can be prevented from being corroded due to defects caused by the corrosion of the insulating layer 20.

[0037] The substrate 10 may contain GaN. A chemical solution containing H2O2 is often used as an etching solution. This H2O2 may oxidize GaN and form Ga2O3. Therefore, when GaN is used as the substrate 10, if the conductive layer 31 is corroded and H2O2 penetrates into the substrate 10, Ga2O3 may be formed between the GaN and the conductive layer 31, and the substrate 10 may no longer function as a semiconductor. Therefore, the structure of the electronic component 1 according to the embodiment can be more effective when the substrate 10 contains GaN.

[0038] The present invention is not limited to the above-described embodiments.

[0039] For example, the structure shown in FIG. 3 may be adopted. The electronic component 1 shown in FIG. 3 further includes a thin film 33 formed on the barrier layer 32. The thin film 33 covers the entire barrier layer 32. The material of the thin film 33 is not particularly limited, but may be, for example, Au, Sn, Pd, or the like. The thickness of the thin film 33 is not particularly limited, but may be 10 nm or more and 300 nm or less. In this case, even if a defect such as a hole exists in the barrier layer 32, the thin film 33 can cover the defect. Therefore, corrosion of the conductive layer 31 by the etching solution can be more reliably suppressed.

[0040] The shape and position of the peak 50 are not limited to those in the above-described embodiment. For example, the structure shown in FIG. 4 may be adopted. In the electronic component 1 shown in FIG. 4, the peak 50 is formed by a protruding portion 60 that protrudes upward from the curved surface 51 in a part of the main body 42. The protruding portion 60 is formed by extending the upper end of the rising portion 41A to a position higher than the other rising portion 41B and drawing an arc with a smaller radius of curvature than the arc of the curved surface 51. The curved surface 51 of the main body 42 does not have any part that protrudes upward other than the protruding portion 60. Therefore, the outer surface 32a of the barrier layer 32 has one peak 50.

[0041] The structure shown in Fig. 5 may be adopted. In electronic component 1 shown in Fig. 5, main body 42 is curved largely throughout. As a result, no corners 43A, 43B (see Fig. 1) are formed between rising portions 41A, 41B and main body 42, and main body 42 is formed so as to describe a continuous arc from rising portions 41A, 41B. As a result of main body 42 being curved largely so as to protrude upward, outer surface 32a of barrier layer 32 has one peak 50.

[0042] The structure shown in Fig. 6 may be adopted. Electronic component 1 shown in Fig. 6 is configured by curving protruding portion 60 shown in Fig. 4 more greatly and curving rising portion 41B and main body portion 42 so as to eliminate corner portion 43B. Main body portion 42 does not have any portion that protrudes upward other than protruding portion 60. Therefore, outer surface 32a of barrier layer 32 has one ridge portion 50.

[0043] The shape of the barrier layer and the shape of the conductive layer do not necessarily have to be the same. For example, the barrier layer may have one peak, and the conductive layer may have two or more peaks.

[0044] [Form 1] 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; a barrier layer covering the conductive layer; An electronic component, wherein at least the outer surface of the barrier layer has a shape having one upwardly protruding ridge. [Form 2] 2. The electronic component of claim 1, wherein the barrier layer extends onto the insulating layer. [Form 3] 3. The electronic component according to claim 1, further comprising a thin film formed on the barrier layer. [Form 4] 4. The electronic component according to any one of aspects 1 to 3, wherein the barrier layer is made of a material containing at least one of Ni, Ta, Ti, W, Mo, Cr, Zn, In, Nb, Sn, and C. [Form 5] 5. The electronic device according to any one of aspects 1 to 4, wherein the barrier layer has a thickness of 100 nm or more. [Form 6] 6. The electronic component according to any one of aspects 1 to 5, wherein the insulating layer contains at least one of silicon oxide, silicon nitride, silicon oxynitride, epoxy resin, and polyimide. [Form 7] 7. The electronic device according to any one of the first to sixth aspects, wherein the substrate comprises GaN. [Explanation of symbols]

[0045] Reference Signs List 1: electronic component, 10: substrate, 20: insulating layer, 31: conductive layer, 32: barrier layer, 50: mountain portion.

Claims

1. 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; a barrier layer covering the conductive layer; An electronic component, wherein at least the outer surface of the barrier layer has a shape having one upwardly protruding ridge.

2. The electronic component of claim 1 , wherein the barrier layer extends onto the insulating layer.

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

4. 2. The electronic component according to claim 1, wherein the barrier layer is made of a material containing 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 barrier layer has a thickness of 100 nm or more.

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

7. The electronic component of claim 1 , wherein the substrate comprises GaN.

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