Semiconductor Device

Abstract

A capacitor 1, which is an embodiment of this semiconductor device, is provided with a substrate 10, a first electrode layer 22 which is provided on the substrate 10, a dielectric film 23 which is provided on the first electrode layer 22 and which covers the end of the first electrode layer 22, a second electrode layer 24 which is provided on the dielectric film 23, a moisture-proof membrane 25 which is provided on the dielectric film 23 and the second electrode layer 24, a protective layer 26 which is provided on the moisture-proof membrane 25, and an external electrode 27 which passes through the protective layer 26. At least part of the lateral surface 24c of the second electrode layer 24 has a tapered shape that tapers inwards from a first primary surface 24a towards a second primary surface 24b.

Description

[Technical field]

[0001] The present invention relates to a semiconductor device. [Background technology]

[0002] A typical capacitor element used in semiconductor integrated circuits is, for example, a metal insulator metal (MIM) capacitor, which has a parallel plate structure in which an insulator is sandwiched between a lower electrode and an upper electrode.

[0003] Patent Document 1 discloses a capacitor component comprising a lower electrode formed on a substrate, a dielectric thin film formed on the lower electrode, an upper electrode formed on the dielectric thin film, an insulating layer formed on the substrate including the upper electrode, and a pair of electrode terminals connected to the electrodes, respectively, and arranged so that their ends are positioned on the same plane. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 5-47586 Summary of the Invention [Problem to be solved by the invention]

[0005] In the capacitor component (capacitor) described in Patent Document 1, the electrode terminal, which is the external electrode, protrudes the most. Therefore, for example, when mounting a semiconductor device such as a capacitor on a wiring board, a load is applied to the most protruding external electrode. If an excessive load is applied to the semiconductor device due to the load being transmitted in the thickness direction of the semiconductor device via the external electrode, there is a risk of a problem that a crack occurs in the dielectric film and the semiconductor device is short-circuited.

[0006] The present invention has been made to solve the above problems, and aims to provide a semiconductor device in which cracks occurring in a dielectric film are suppressed when a load is applied to an external electrode. [Means for solving the problem]

[0007] The semiconductor device of the present invention includes a substrate, a first electrode layer provided on the substrate, a dielectric film provided on the first electrode layer and covering an end of the first electrode layer, a second electrode layer provided on the dielectric film, a moisture-resistant film provided on the dielectric film and the second electrode layer, a protective layer provided on the moisture-resistant film, and an external electrode penetrating the protective layer. The first electrode layer has a first main surface on the substrate side, a second main surface on the dielectric film side, and a side surface connecting the first main surface and the second main surface. The second electrode layer has a first main surface on the dielectric film side, a second main surface on the moisture-resistant film side, and a side surface connecting the first main surface and the second main surface. At least a part of the side surface of the second electrode layer has a tapered shape inclined inward from the first main surface toward the second main surface. Effect of the Invention

[0008] According to the present invention, it is possible to provide a semiconductor device in which cracks occurring in a dielectric film when a load is applied to an external electrode are suppressed. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view illustrating an example of a capacitor according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view illustrating an example of the capacitor according to the first embodiment of the present invention. [Diagram 3] FIG. 3 is an enlarged cross-sectional view of a side surface of a second electrode layer constituting the capacitor shown in FIG. [Figure 4-1] FIG. 4-1 is a graph showing the relationship between the taper angle θA and the stress at point A. [Figure 4-2]FIG. 4-2 is a schematic diagram for explaining a method for measuring the taper angle θA. [Diagram 5] FIG. 5 is a cross-sectional view illustrating an example of a capacitor according to a second embodiment of the present invention. [Figure 6] FIG. 6 is a cross-sectional view illustrating an example of a capacitor according to a third embodiment of the present invention. [Figure 7] FIG. 7 is an enlarged cross-sectional view of the side surfaces of the first electrode layer and the second electrode layer that constitute the capacitor shown in FIG. [Figure 8] FIG. 8 is a cross-sectional view illustrating an example of a capacitor according to a fourth embodiment of the present invention. [Figure 9] FIG. 9 is an enlarged cross-sectional view of a side surface of a third electrode layer constituting the capacitor shown in FIG. [Figure 10] FIG. 10 is a cross-sectional view illustrating an example of a capacitor according to a fifth embodiment of the present invention. [Figure 11] FIG. 11 is a cross-sectional view illustrating an example of a capacitor according to a sixth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The semiconductor device of the present invention will now be described. However, the present invention is not limited to the following configurations, and can be appropriately modified and applied within the scope of the present invention. Note that the present invention also includes a combination of two or more of the individual preferred configurations of the present invention described below.

[0011] The following embodiments are merely examples, and it goes without saying that partial replacement or combination of the configurations shown in the different embodiments is possible. In the second and subsequent embodiments, the description of the matters common to the first embodiment will be omitted, and only the differences will be described. In particular, the same effects and advantages due to the same configuration will not be mentioned one by one for each embodiment.

[0012] In the following description, unless otherwise specified, each embodiment is simply referred to as the "semiconductor device of the present invention." The shape and arrangement of each component of the semiconductor device of the present invention are not limited to the examples shown in the drawings.

[0013] In the following, a capacitor will be described as an example of one embodiment of the semiconductor device of the present invention. The semiconductor device of the present invention may be a capacitor itself (i.e., a capacitor element) or a device including a capacitor.

[0014] [First embodiment] In the capacitor according to the first embodiment of the present invention, the second electrode layer is made of a single conductive layer.

[0015] Fig. 1 is a cross-sectional view showing an example of a capacitor according to a first embodiment of the present invention. Fig. 2 is a plan view showing an example of a capacitor according to a first embodiment of the present invention. Fig. 1 is a cross-sectional view taken along line II of the capacitor shown in Fig. 2.

[0016] In this specification, the length direction, width direction, and thickness direction of a capacitor (semiconductor device) are defined as the directions indicated by arrows L, W, and T, respectively, as shown in Figures 1 and 2. Here, the length direction L, width direction W, and thickness direction T are perpendicular to each other.

[0017] 1 and 2 includes a substrate 10, an insulating film 21 provided on the substrate 10, a first electrode layer 22 provided on the insulating film 21, a dielectric film 23 provided on the first electrode layer 22 and covering an end of the first electrode layer 22, a second electrode layer 24 provided on the dielectric film 23, a moisture-resistant film 25 provided on the dielectric film 23 and the second electrode layer 24, a protective layer 26 provided on the moisture-resistant film 25, and an external electrode 27 penetrating the protective layer 26. The external electrode 27 includes a first external electrode 27A connected to the first electrode layer 22 and a second external electrode 27B connected to the second electrode layer 24. The first external electrode 27A penetrates the protective layer 26, the moisture-resistant film 25, and the dielectric film 23, and the second external electrode 27B penetrates the protective layer 26 and the moisture-resistant film 25.

[0018] The substrate 10 is not particularly limited, but is preferably a semiconductor substrate such as a silicon substrate or a gallium arsenide substrate, or an insulating substrate such as glass or alumina.

[0019] The insulating film 21 may be provided so as to cover the entirety of one main surface of the substrate 10, or may be provided so as to cover a part of it, but it needs to be provided in a region larger than the first electrode layer 22 and overlapping the entirety of the first electrode layer 22. When the substrate 10 is an insulating substrate such as glass or alumina, the insulating film 21 does not need to be provided.

[0020] The material constituting the insulating film 21 is not particularly limited, but preferable examples include SiO2, SiN, Al2O3, HfO2, Ta2O5, and ZrO2.

[0021] The first electrode layer 22 is provided at a position away from the end of the substrate 10. That is, the end of the first electrode layer 22 is located inside the end of the substrate 10. The first electrode layer 22 has a first main surface 22a on the substrate 10 side, a second main surface 22b on the dielectric film 23 side, and a side surface 22c connecting the first main surface 22a and the second main surface 22b.

[0022] The first electrode layer 22 may have a structure consisting of a single conductive layer, or may have a structure consisting of multiple conductive layers stacked in the thickness direction (the direction indicated by the arrow T in Figures 1 and 2).

[0023] The material constituting the first electrode layer 22 is not particularly limited, but is preferably Cu, Ag, Au, Al, Ni, Cr or Ti, or an alloy containing at least one of these metals.

[0024] The dielectric film 23 is provided so as to cover the first electrode layer 22 except for the opening. The dielectric film 23 is also provided on the surface of the insulating film 21 from the end of the first electrode layer 22 to the end of the insulating film 21. That is, the dielectric film 23 is provided so as to cover the end of the first electrode layer 22. Furthermore, the dielectric film 23 may also be provided on the surface of the substrate 10 from the end of the insulating film 21 to the end of the substrate 10. That is, the dielectric film 23 may be provided so as to cover the end of the insulating film 21.

[0025] The material constituting the dielectric film 23 is not particularly limited, but preferably includes oxides or nitrides such as SiO2, SiN, Al2O3, HfO2, and Ta2O5.

[0026] The second electrode layer 24 is provided opposite the first electrode layer 22 with the dielectric film 23 interposed therebetween. The second electrode layer 24 has a first main surface 24a on the dielectric film 23 side, a second main surface 24b on the moisture-resistant film 25 side, and a side surface 24c connecting the first main surface 24a and the second main surface 24b.

[0027] The second electrode layer 24 has a structure made of a single conductive layer.

[0028] The material constituting the second electrode layer 24 is not particularly limited, but is preferably Cu, Ag, Au, Al, Ni, Cr or Ti, or an alloy containing at least one of these metals.

[0029] FIG. 3 is an enlarged cross-sectional view of a side surface of a second electrode layer constituting the capacitor shown in FIG.

[0030] As shown in FIGS. 1 and 3, the side surface 24c of the second electrode layer 24 has a tapered shape that slopes inward from the first main surface 24a on the dielectric film 23 side to the second main surface 24b on the moisture-resistant film 25 side.

[0031] The moisture-resistant film 25 is provided so as to cover the dielectric film 23 and the second electrode layer 24 except for the openings. By providing the moisture-resistant film 25, the moisture resistance of the capacitor element, particularly the dielectric film 23, is improved.

[0032] The material constituting the moisture-resistant film 25 is not particularly limited, but preferably includes moisture-resistant materials such as SiO2 and SiN.

[0033] The protective layer 26 has openings at positions overlapping the openings of the dielectric film 23 and the moisture-resistant film 25 (openings overlapping the first electrode layer 22) and at a position overlapping the opening of the moisture-resistant film 25 (openings overlapping the second electrode layer 24). By providing the protective layer 26, the capacitor element, in particular the dielectric film 23, is protected from moisture.

[0034] The material constituting the protective layer 26 is not particularly limited, but preferable examples include resin materials such as polyimide resin and resin in solder resist.

[0035] The material constituting the external electrode 27 is not particularly limited, but preferably includes Cu, Ni, Ag, Au, Al, etc. The external electrode 27 may have a single-layer structure or a multi-layer structure. The outermost surface of the external electrode 27 is preferably made of Au or Sn.

[0036] When the first external electrode 27A has a multi-layer structure, the first external electrode 27A may have, in order from the substrate 10 side, a seed layer 28a, a first plating layer 28b, and a second plating layer 28c, as shown in FIG.

[0037] The seed layer 28a of the first external electrode 27A may be, for example, a laminate (Ti / Cu) of a conductive layer made of titanium (Ti) and a conductive layer made of copper (Cu).

[0038] An example of a material for the first plating layer 28b of the first external electrode 27A is nickel (Ni).

[0039] Examples of materials for the second plating layer 28c of the first external electrode 27A include gold (Au) and tin (Sn).

[0040] When the second external electrode 27B has a multi-layer structure, the second external electrode 27B may have, in order from the substrate 10 side, a seed layer 28a, a first plating layer 28b, and a second plating layer 28c, as shown in FIG.

[0041] The seed layer 28a of the second external electrode 27B may be, for example, a laminate (Ti / Cu) of a conductive layer made of titanium (Ti) and a conductive layer made of copper (Cu).

[0042] An example of a material for the first plating layer 28b of the second external electrode 27B is nickel (Ni).

[0043] Examples of materials for the second plating layer 28c of the second external electrode 27B include gold (Au) and tin (Sn).

[0044] The constituent materials of the first external electrode 27A and the second external electrode 27B may be the same as or different from each other.

[0045] 1 and 2, a first resin body 31 may be provided between the first external electrode 27A and the second external electrode 27B in a plan view from the thickness direction T. The first resin body 31 is provided on the surface of the protective layer 26, for example.

[0046] As shown in FIG. 1, the tip of the first resin body 31 is preferably located higher than the tips of the first external electrode 27A and the second external electrode 27B in the thickness direction T. In this case, when the capacitor 1 is mounted on the wiring board, the first resin body 31 comes into contact with the wiring board (for example, the upper surface, land, solder, etc. of the wiring board) before the first external electrode 27A and the second external electrode 27B. Therefore, a load is applied to the first resin body 31, and the load applied to the first external electrode 27A and the second external electrode 27B is suppressed. As a result, the load is prevented from being transmitted to the capacitor element via the first external electrode 27A and the second external electrode 27B, and therefore damage to the capacitor element, particularly damage to the dielectric film 23, is suppressed.

[0047] The first resin body 31 preferably contains at least one resin selected from the group consisting of a resin in a solder resist, a polyimide resin, a polyimide amide resin, and an epoxy resin. The first resin body 31 is preferably a cured product of a photosensitive resin.

[0048] The first resin body 31 may include a first wall portion 31a provided on the first external electrode 27A side and a second wall portion 31b provided on the second external electrode 27B side and separated from the first wall portion 31a. In a plan view as shown in Fig. 2, the first wall portion 31a and the second wall portion 31b are preferably provided in parallel.

[0049] The first wall 31a may have an opening communicating with a space separating the first wall 31a and the second wall 31b. Similarly, the second wall 31b may have an opening communicating with a space separating the first wall 31a and the second wall 31b.

[0050] 1 and 2, a second resin body 32 may be provided between an end of the substrate 10 and the first external electrode 27A, and between an end of the substrate 10 and the second external electrode 27B, in a plan view from the thickness direction T. The second resin body 32 is provided, for example, on the surface of the protective layer 26. The second resin body 32 may also be provided outside the protective layer 26, in which case it may be provided on the substrate 10.

[0051] 1, it is preferable that the tip of the second resin body 32 is located higher than the tips of the first external electrode 27A and the second external electrode 27B in the thickness direction T. In this case, for example, when mounting the capacitor 1 on a wiring board, the load can be distributed more widely by the second resin body 32, so that the load applied to the capacitor element, in particular, the dielectric film 23, is sufficiently suppressed.

[0052] 1, the tip of the second resin body 32 is preferably located lower than the tip of the first resin body 31 in the thickness direction T. In this case, for example, when the capacitor 1 is mounted on a wiring board, the capacitor 1 can be stably held on the wiring board by the first resin body 31.

[0053] The second resin body 32 preferably contains at least one resin selected from the group consisting of a resin in a solder resist, a polyimide resin, a polyimide amide resin, and an epoxy resin. The second resin body 32 is preferably a cured product of a photosensitive resin.

[0054] The resin contained in the first resin body 31 and the resin contained in the second resin body 32 may be the same as or different from each other.

[0055] As shown in Figure 2, the second resin body 32 preferably has a first outer peripheral portion 32a provided along the end of the substrate 10 between the end of the substrate 10 and the first external electrode 27A when viewed in a plane from the thickness direction T, and a second outer peripheral portion 32b provided along the end of the substrate 10 between the end of the substrate 10 and the second external electrode 27B.

[0056] The first wall portion 31a and the first outer peripheral portion 32a are preferably connected to each other, and the second wall portion 31b and the second outer peripheral portion 32b are preferably connected to each other.

[0057] As described above, the capacitor 1 shown in FIG. 1 is characterized in that the side surface 24c of the second electrode layer 24 has a tapered shape that slopes inward from the first main surface 24a toward the second main surface 24b.

[0058] 3, by having the side surface 24c of the second electrode layer 24 have the above-mentioned tapered shape, it is possible to reduce the stress at the stress concentration point A on the moisture-resistant film 25 provided at the end of the second electrode layer 24 when a load is applied to the external electrode 27 (particularly the second external electrode 27B). Therefore, it is possible to alleviate the stress on the moisture-resistant film 25, and therefore it is possible to reduce the stress applied to the moisture-resistant film 25 and the dielectric film 23 provided under the second electrode layer 24. As a result, it is possible to suppress the occurrence of cracks in the dielectric film 23.

[0059] Figure 4-1 shows the taper angle θ A1 is a graph showing the relationship between the taper angle θ and the stress at point A. A means the angle of the side surface 24c of the second electrode layer 24 with respect to the first main surface 24a of the second electrode layer 24, as shown in FIG.

[0060] The stress at point A was calculated by performing a simulation using the finite element method. When the side surface 24c of the second electrode layer 24 does not have a tapered shape, the taper angle θ A is 90°. The relative values ​​normalized with the stress at point A set to 100% are shown in Figure 4-1.

[0061] From Figure 4-1, the taper angle θ A It can be seen that the magnitude of the stress at point A, which is the stress concentration point on the moisture-resistant film 25, decreases as the angle becomes smaller than 90°.

[0062] In particular, the taper angle θ A When the taper angle θ is 45° or less, the effect of reducing the stress at point A is high. A The smaller the taper angle θ A If the angle θ is less than 20°, the area of ​​the second main surface 24b relative to the first main surface 24a of the second electrode layer 24 becomes small, making it difficult to ensure the contact area with the second external electrode 27B. A When θ is 20° or less, A It is preferable that it is ≦45°.

[0063] Figure 4-2 shows the taper angle θ A FIG. 2 is a schematic diagram for explaining a method for measuring the amount of

[0064] 4-2, when the film thickness of the second electrode layer 24 is T, the point where a line segment parallel to the first main surface 24a of the second electrode layer 24 and having a height of 1 / 2T intersects with a line segment along the side surface 24c of the second electrode layer 24 is X. The angle connecting the first main surface 24a of the second electrode layer 24, the vertex O, and the point X is the taper angle θ. AThe taper angle θ B and θ C can also be measured in a similar manner.

[0065] Generally, the second electrode layer 24 is made of the above-mentioned metal, etc. In this case, a desired tapered shape can be easily formed on the side surface 24c of the second electrode layer 24 by using a method such as wet etching or dry etching.

[0066] 1, the side surface 22c of the first electrode layer 22 does not have a tapered shape. That is, the angle θ of the side surface 22c of the first electrode layer 22 with respect to the first major surface 22a of the first electrode layer 22 is B (see FIG. 7) is 90°. In this way, the angle θ of the side surface 24c of the second electrode layer 24 with respect to the first main surface 24a of the second electrode layer 24 is A The angle of the side surface 22c of the first electrode layer 22 with respect to the first main surface 22a of the first electrode layer 22 is defined as θ B Then, θ A <θ B It is preferable that:

[0067] The tapered shape of the second electrode layer 24 may be formed on a part of the side surface of the second electrode layer 24, or may be formed on the entire side surface. However, the load applied to the external electrode 27 (particularly the second external electrode 27B) is applied isotropically in the planar direction of the film such as the moisture-resistant film 25. Therefore, from the viewpoint of reducing the stress applied to the dielectric film 23, it is preferable that the entire side surface of the second electrode layer 24 has a tapered shape.

[0068] As shown in Figs. 1 and 2, when viewed in plan from the thickness direction T, the outer shape of the second external electrode 27B is preferably smaller than the outer shape of the second electrode layer 24. If the outer shape of the second external electrode 27B is equal to or larger than the outer shape of the second electrode layer 24, the load applied to the external electrode 27 (particularly the second external electrode 27B) is more likely to be applied to the dielectric film 23. In contrast, if the outer shape of the second external electrode 27B is smaller than the outer shape of the second electrode layer 24, the second electrode layer 24 is present directly below the second external electrode 27B, so that the load applied to the external electrode 27 (particularly the second external electrode 27B) is less likely to be applied to the dielectric film 23. As a result, the occurrence of cracks in the dielectric film 23 can be further suppressed.

[0069] The capacitor 1 shown in FIG. 1 can be manufactured by a known method, for example, as described in International Publication No. WO 2019 / 021827, except for forming a tapered shape in the second electrode layer 24.

[0070] [Second embodiment] In a capacitor according to a second embodiment of the present invention, as a modification of the first embodiment, the second electrode layer is made of a multi-layer conductive layer.

[0071] FIG. 5 is a cross-sectional view illustrating an example of a capacitor according to a second embodiment of the present invention.

[0072] In the capacitor 2 shown in Fig. 5, the second electrode layer 24 is made of multiple conductive layers stacked in the thickness direction (the direction indicated by the arrow T in Fig. 5). The number of conductive layers is not particularly limited. It is sufficient that the side surface of at least one conductive layer has a tapered shape, but it is preferable that the side surface of each conductive layer has a tapered shape.

[0073] In the second electrode layer 24, among the conductive layers adjacent in the thickness direction T, the conductive layer closer to the moisture-resistant film 25 has a smaller area in a plan view in the thickness direction T than the conductive layer closer to the dielectric film 23. The taper angles of the conductive layers may be the same or different.

[0074] Capacitor 2 shown in FIG. 5 also provides the same effects as capacitor 1 shown in FIG.

[0075] [Third embodiment] In a capacitor according to a third embodiment of the present invention, as a modification of the first and second embodiments, not only the side surface of the second electrode layer but also the side surface of the first electrode layer has a tapered shape.

[0076] Fig. 6 is a cross-sectional view showing an example of a capacitor according to a third embodiment of the present invention, and Fig. 7 is an enlarged cross-sectional view showing the side surfaces of a first electrode layer and a second electrode layer constituting the capacitor shown in Fig. 6.

[0077] 6, the side surface 22c of the first electrode layer 22 has a tapered shape that is inclined inward from the first main surface 22a to the second main surface 22b. Furthermore, as shown in FIG. 7, the angle of the side surface 24c of the second electrode layer 24 with respect to the first main surface 24a of the second electrode layer 24 is set to θ A The angle of the side surface 22c of the first electrode layer 22 with respect to the first main surface 22a of the first electrode layer 22 is defined as θ B Then, θ A <θ B It is.

[0078] As shown in FIG. 7, when the side surface 24c of the second electrode layer 24 and the side surface 22c of the first electrode layer 22 have a tapered shape, θ A <θ B This makes it possible to make the stress at the stress concentration point A on the moisture-resistant film 25 provided on the end of the second electrode layer 24 smaller than the stress at the stress concentration point B on the moisture-resistant film 25 along the end of the first electrode layer 22. Therefore, it is possible to relatively reduce the stress applied to the moisture-resistant film 25 and the dielectric film 23 provided under the second electrode layer 24. As a result, it is possible to suppress the occurrence of cracks in the dielectric film 23.

[0079] The angle of the side surface 24c of the second electrode layer 24 with respect to the first main surface 24a of the second electrode layer 24 is defined as θ A When θ is 20° or less, A It is preferable that it is ≦45°.

[0080] The angle of the side surface 22c of the first electrode layer 22 with respect to the first main surface 22a of the first electrode layer 22 is defined as θ B Then, 25°≦θ B It is preferable that the angle is ≦70°.

[0081] The tapered shape of the second electrode layer 24 may be formed on a part of the side surface of the second electrode layer 24 or on the entire surface, but it is preferable that the entire side surface of the second electrode layer 24 has a tapered shape. The tapered shape of the first electrode layer 22 may be formed on a part of the side surface of the first electrode layer 22 or on the entire surface, but it is preferable that the entire side surface of the first electrode layer 22 has a tapered shape.

[0082] [Fourth embodiment] A capacitor according to a fourth embodiment of the present invention further includes a third electrode layer provided on the dielectric film at a distance from the second electrode layer, and the external electrodes include a first external electrode connected to the third electrode layer and a second external electrode connected to the second electrode layer. In the capacitor according to the fourth embodiment of the present invention, the second electrode layer is made of a single conductive layer.

[0083] FIG. 8 is a cross-sectional view illustrating an example of a capacitor according to a fourth embodiment of the present invention.

[0084] 8 includes a substrate 10, an insulating film 21 provided on the substrate 10, a first electrode layer 22 provided on the insulating film 21, a dielectric film 23 provided on the first electrode layer 22, a second electrode layer 24 provided on the dielectric film 23, a third electrode layer 29 provided on the dielectric film 23 and spaced apart from the second electrode layer 24, a moisture-resistant film 25 provided on the dielectric film 23, the second electrode layer 24, and the third electrode layer 29, a protective layer 26 provided on the moisture-resistant film 25, and an external electrode 27 penetrating the protective layer 26. The external electrode 27 includes a first external electrode 27A connected to the third electrode layer 29 and a second external electrode 27B connected to the second electrode layer 24. The first external electrode 27A penetrates the protective layer 26 and the moisture-resistant film 25, and the second external electrode 27B penetrates the protective layer 26 and the moisture-resistant film 25.

[0085] In the configuration of the capacitor 1 shown in FIG. 1, a capacitor is formed on the left side, whereas in the configuration of the capacitor 4 shown in FIG. 8, capacitors are formed on the left and right sides. In the configuration shown in FIG. 8, the portion where the first external electrode 27A is connected to the first electrode layer 22 in the configuration shown in FIG. 1 is simply replaced with a configuration in which the first electrode layer 22, the dielectric film 23, and the third electrode layer 29 are provided in this order. Therefore, the configuration shown in FIG. 8 does not require additional element formation space compared to the configuration shown in FIG. 1. Therefore, a capacitor with a low capacitance can be fabricated while maintaining the same element area. Such a structure is effective when it is impossible to form a dielectric film with a certain thickness or more.

[0086] The third electrode layer 29 is provided opposite the first electrode layer 22 with the dielectric film 23 interposed therebetween. The third electrode layer 29 has a first main surface 29a on the dielectric film 23 side, a second main surface 29b on the moisture-resistant film 25 side, and a side surface 29c connecting the first main surface 29a and the second main surface 29b.

[0087] The third electrode layer 29 has a structure made of a single conductive layer.

[0088] The material constituting the third electrode layer 29 is not particularly limited, but is preferably Cu, Ag, Au, Al, Ni, Cr or Ti, or an alloy containing at least one of these metals.

[0089] FIG. 9 is an enlarged cross-sectional view of a side surface of a third electrode layer constituting the capacitor shown in FIG.

[0090] As shown in FIGS. 8 and 9, the side surface 29c of the third electrode layer 29 has a tapered shape that slopes inward from the first main surface 29a on the dielectric film 23 side to the second main surface 29b on the moisture-resistant film 25 side.

[0091] 9, by having the side surface 29c of the third electrode layer 29 have the above-mentioned tapered shape, it is possible to reduce the stress at the stress concentration point C on the moisture-resistant film 25 provided at the end of the third electrode layer 29 when a load is applied to the external electrode 27 (particularly the first external electrode 27A). Therefore, it is possible to alleviate the stress in the moisture-resistant film 25, and therefore it is possible to reduce the stress applied to the moisture-resistant film 25 and the dielectric film 23 provided under the third electrode layer 29. As a result, it is possible to suppress the occurrence of cracks in the dielectric film 23.

[0092] Therefore, the capacitor 4 shown in FIG. 8 also provides the same effects as the capacitor 1 shown in FIG.

[0093] The angle of the side surface 24c of the second electrode layer 24 with respect to the first main surface 24a of the second electrode layer 24 is defined as θ A When θ is 20° or less, A It is preferable that the angle is ≦45°.

[0094] The angle of the side surface 29c of the third electrode layer 29 with respect to the first main surface 29a of the third electrode layer 29 is defined as θ C When θ is 20° or less, C The taper angle θ of the third electrode layer 29 is preferably ≦45°. C is the taper angle θ of the second electrode layer 24 A It may be the same as or different from.

[0095] 8, the side surface 22c of the first electrode layer 22 does not have a tapered shape. That is, the angle θ of the side surface 22c of the first electrode layer 22 with respect to the first main surface 22a of the first electrode layer 22 is B (see FIG. 7) is 90°. In this way, the angle θ of the side surface 24c of the second electrode layer 24 with respect to the first main surface 24a of the second electrode layer 24 is A The angle of the side surface 22c of the first electrode layer 22 with respect to the first main surface 22a of the first electrode layer 22 is defined as θ B The angle of the side surface 29c of the third electrode layer 29 with respect to the first main surface 29a of the third electrode layer 29 is defined as θ C Then, θ A <θ B And θ C<θ B It is preferable that:

[0096] The tapered shape of the second electrode layer 24 may be formed on a part of the side surface of the second electrode layer 24 or on the entire surface, but it is preferable that the entire side surface of the second electrode layer 24 has a tapered shape. Similarly, the tapered shape of the third electrode layer 29 may be formed on a part of the side surface of the third electrode layer 29 or on the entire surface, but it is preferable that the entire side surface of the third electrode layer 29 has a tapered shape.

[0097] 8, when viewed in a plane from the thickness direction T, it is preferable that the outer shape of the first external electrode 27A is smaller than that of the third electrode layer 29, and the outer shape of the second external electrode 27B is smaller than that of the second electrode layer 24. If the outer shape of the first external electrode 27A is equal to or larger than that of the third electrode layer 29, the load applied to the external electrode 27 (particularly the first external electrode 27A) is more likely to be applied to the dielectric film 23. If the outer shape of the second external electrode 27B is equal to or larger than that of the second electrode layer 24, the load applied to the external electrode 27 (particularly the second external electrode 27B) is more likely to be applied to the dielectric film 23. In contrast, when the outer shape of the first external electrode 27A is smaller than that of the third electrode layer 29 and the outer shape of the second external electrode 27B is smaller than that of the second electrode layer 24, the third electrode layer 29 is present directly below the first external electrode 27A and the second electrode layer 24 is present directly below the second external electrode 27B, so that the load on the external electrodes 27 (the first external electrode 27A and the second external electrode 27B) is less likely to be applied to the dielectric film 23. As a result, the occurrence of cracks in the dielectric film 23 can be further suppressed.

[0098] [Fifth embodiment] A capacitor according to a fifth embodiment of the present invention is a modification of the fourth embodiment, in which the second electrode layer is made of a multi-layer conductive layer, and the third electrode layer is made of a multi-layer conductive layer.

[0099] FIG. 10 is a cross-sectional view illustrating an example of a capacitor according to a fifth embodiment of the present invention.

[0100] In the capacitor 5 shown in Fig. 10, the second electrode layer 24 is made of multiple conductive layers stacked in the thickness direction (the direction indicated by the arrow T in Fig. 10). The number of conductive layers is not particularly limited. It is sufficient that the side surface of at least one conductive layer has a tapered shape, but it is preferable that the side surface of each conductive layer has a tapered shape.

[0101] In the second electrode layer 24, among the conductive layers adjacent in the thickness direction T, the conductive layer closer to the moisture-resistant film 25 has a smaller area in a plan view in the thickness direction T than the conductive layer closer to the dielectric film 23. The taper angles of the conductive layers may be the same or different.

[0102] Similarly, the third electrode layer 29 is composed of multiple conductive layers stacked in the thickness direction T. The number of conductive layers is not particularly limited. It is sufficient that the side surface of at least one conductive layer has a tapered shape, but it is preferable that the side surface of each conductive layer has a tapered shape. The number of conductive layers included in the third electrode layer 29 may be the same as or different from the number of conductive layers included in the second electrode layer 24.

[0103] In the third electrode layer 29, among the conductive layers adjacent in the thickness direction T, the conductive layer closer to the moisture-resistant film 25 has a smaller area in a plan view in the thickness direction T than the conductive layer closer to the dielectric film 23. The taper angles of the conductive layers may be the same or different.

[0104] Capacitor 5 shown in FIG. 10 also provides the same effects as capacitor 2 shown in FIG.

[0105] [Sixth embodiment] In a capacitor according to a sixth embodiment of the present invention, as a modification of the fourth and fifth embodiments, not only the side surface of the second electrode layer but also the side surface of the first electrode layer has a tapered shape.

[0106] FIG. 11 is a cross-sectional view illustrating an example of a capacitor according to a sixth embodiment of the present invention.

[0107] 11, the side surface 22c of the first electrode layer 22 has a tapered shape that is inclined inward from the first main surface 22a to the second main surface 22b. Furthermore, the angle of the side surface 24c of the second electrode layer 24 with respect to the first main surface 24a of the second electrode layer 24 is set to θ A The angle of the side surface 22c of the first electrode layer 22 with respect to the first main surface 22a of the first electrode layer 22 is defined as θ B The angle of the side surface 29c of the third electrode layer 29 with respect to the first main surface 29a of the third electrode layer 29 is defined as θ C Then, θ A <θ B And θ C <θ B It is.

[0108] Capacitor 5 shown in FIG. 10 also provides the same effects as capacitor 3 shown in FIG.

[0109] The angle of the side surface 24c of the second electrode layer 24 with respect to the first main surface 24a of the second electrode layer 24 is defined as θ A When θ is 20° or less, A It is preferable that the angle is ≦45°.

[0110] The angle of the side surface 29c of the third electrode layer 29 with respect to the first main surface 29a of the third electrode layer 29 is defined as θ C When θ is 20° or less, C The taper angle θ of the third electrode layer 29 is preferably ≦45°. C is the taper angle θ of the second electrode layer 24 A It may be the same as or different from.

[0111] The angle of the side surface 22c of the first electrode layer 22 with respect to the first main surface 22a of the first electrode layer 22 is defined as θ B Then, 25°≦θ B It is preferable that the angle is ≦70°.

[0112] The tapered shape of the second electrode layer 24 may be formed on a part of the side surface of the second electrode layer 24 or on the entire surface, but it is preferable that the entire side surface of the second electrode layer 24 has a tapered shape. Similarly, the tapered shape of the third electrode layer 29 may be formed on a part of the side surface of the third electrode layer 29 or on the entire surface, but it is preferable that the entire side surface of the third electrode layer 29 has a tapered shape. Furthermore, the tapered shape of the first electrode layer 22 may be formed on a part of the side surface of the first electrode layer 22 or on the entire surface, but it is preferable that the entire side surface of the first electrode layer 22 has a tapered shape.

[0113] [Other embodiments] The semiconductor device of the present invention is not limited to the above-described embodiment, and various applications and modifications can be made within the scope of the present invention with respect to the configuration and manufacturing conditions of the semiconductor device such as a capacitor.

[0114] For example, in the fifth embodiment of the present invention, a capacitor has been described in which the second electrode layer is made of a multi-layer conductive layer and the third electrode layer is made of a multi-layer conductive layer, but the capacitor may also have one of the second and third electrode layers made of a single conductive layer and the other made of a multi-layer conductive layer. [Explanation of symbols]

[0115] 1, 2, 3, 4, 5, 6 Capacitor (semiconductor device) 10 Substrate 21 Insulating film 22 1st electrode layer 22a: First main surface of the first electrode layer 22b Second main surface of the first electrode layer 22c Side of the first electrode layer 23 Dielectric Film 24 Second electrode layer 24a: First main surface of second electrode layer 24b Second main surface of second electrode layer 24c Side of the second electrode layer 25 Moisture-resistant film 26 Protective layer 27 External electrode 27A 1st external electrode 27B 2nd external electrode 28a Seed layer 28b First plating layer 28c Second plating layer 29 Third electrode layer 29a: First main surface of the third electrode layer 29b second main surface of third electrode layer 29c Side of the third electrode layer 31 First resin body 31a 1st wall 31b 2nd wall part 32 Second resin body 32a 1st outer periphery 32b 2nd outer periphery A, B, C Stress concentration points on the moisture-resistant film θ A Angle of a side surface of the second electrode layer with respect to a first main surface of the second electrode layer θ B Angle of a side surface of the first electrode layer with respect to a first main surface of the first electrode layer θ C Angle of a side surface of the third electrode layer with respect to a first main surface of the third electrode layer

Claims

1. A substrate; A first electrode layer provided on the substrate; a dielectric film provided on the first electrode layer and covering an end portion of the first electrode layer; a second electrode layer provided on the dielectric film; a moisture-resistant film provided on the dielectric film and the second electrode layer; a protective layer provided on the moisture-resistant film; an external electrode penetrating the protective layer; Equipped with the first electrode layer has a first main surface on the substrate side, a second main surface on the dielectric film side, and a side surface connecting the first main surface and the second main surface; the second electrode layer has a first main surface on the dielectric film side, a second main surface on the moisture-resistant film side, and a side surface connecting the first main surface and the second main surface, At least a part of the side surface of the second electrode layer has a tapered shape inclined inward from the first main surface toward the second main surface, the external electrodes include a first external electrode connected to the first electrode layer and a second external electrode connected to the second electrode layer; The angle of the side surface of the second electrode layer with respect to the first main surface of the second electrode layer is defined as θ Ａ , the angle of the side surface of the first electrode layer with respect to the first main surface of the first electrode layer is θ Ｂ Then, θ Ａ <θ Ｂ and A semiconductor device, wherein at least a portion of the side surface of the first electrode layer has a tapered shape that slopes inward from the first main surface toward the second main surface.

2. The semiconductor device according to claim 1 , wherein the second electrode layer is made of a single conductive layer.

3. The second electrode layer is made of a multi-layer conductive layer stacked in a thickness direction, 2 . The semiconductor device according to claim 1 , wherein, of the conductive layers adjacent in the thickness direction, the conductive layer closer to the moisture-resistant film has a smaller area in a plan view in the thickness direction than the conductive layer closer to the dielectric film.

4. 4. The semiconductor device according to claim 1, wherein, when viewed in a plan view from the thickness direction, an outer shape of said second external electrode is smaller than an outer shape of said second electrode layer.

5. A substrate; A first electrode layer provided on the substrate; a dielectric film provided on the first electrode layer and covering an end portion of the first electrode layer; a second electrode layer provided on the dielectric film; a third electrode layer provided on the dielectric film and spaced apart from the second electrode layer; a moisture-resistant film provided on the dielectric film and the second electrode layer; a protective layer provided on the moisture-resistant film; an external electrode penetrating the protective layer; Equipped with the external electrodes include a first external electrode connected to the third electrode layer and a second external electrode connected to the second electrode layer; the first electrode layer has a first main surface on the substrate side, a second main surface on the dielectric film side, and a side surface connecting the first main surface and the second main surface; the second electrode layer has a first main surface on the dielectric film side, a second main surface on the moisture-resistant film side, and a side surface connecting the first main surface and the second main surface, the third electrode layer has a first main surface on the dielectric film side, a second main surface on the moisture-resistant film side, and a side surface connecting the first main surface and the second main surface, At least a part of the side surface of the second electrode layer has a tapered shape inclined inward from the first main surface toward the second main surface, At least a part of the side surface of the third electrode layer has a tapered shape inclined inward from the first main surface toward the second main surface, The angle of the side surface of the second electrode layer with respect to the first main surface of the second electrode layer is defined as θ Ａ , the angle of the side surface of the first electrode layer with respect to the first main surface of the first electrode layer is θ Ｂ θC is the angle of the side surface of the third electrode layer with respect to the first main surface of the third electrode layer, Ａ <θ Ｂ and θ C <θ B ; A semiconductor device, wherein at least a portion of the side surface of the first electrode layer has a tapered shape that slopes inward from the first main surface toward the second main surface.

6. the second electrode layer is made of a single conductive layer having the tapered shape, The semiconductor device according to claim 5 , wherein the third electrode layer is made of a single conductive layer having the tapered shape.

7. the second electrode layer is made of multiple conductive layers stacked in a thickness direction, each of which has the tapered shape; the third electrode layer is made of multiple conductive layers stacked in the thickness direction, each of which has the tapered shape; 6. The semiconductor device according to claim 5, wherein, of the conductive layers adjacent in the thickness direction, the conductive layer closer to the moisture-resistant film has a smaller area in a plan view in the thickness direction than the conductive layer closer to the dielectric film.

8. The semiconductor device according to any one of claims 5 to 7, wherein, when viewed in a plane from the thickness direction, an outer shape of the first external electrode is smaller than an outer shape of the third electrode layer, and an outer shape of the second external electrode is smaller than an outer shape of the second electrode layer.

9. The angle of the side surface of the second electrode layer with respect to the first main surface of the second electrode layer is defined as θ Ａ When 20°≦θ Ａ The semiconductor device according to claim 1 , wherein the angle is ≦45°.

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