Semiconductor device manufacturing method and semiconductor device

Abstract

To provide a manufacturing method of a semiconductor device in which an electrode made of a metal material that dissolves in a developing solution or a stripping solution is disposed on a semiconductor element surface, and the semiconductor device manufactured by the manufacturing method.SOLUTION: A method includes steps of: preparing a wafer on which an electrode 11 of a semiconductor element 10 is formed, the electrode made of a metal material that dissolves in a developing solution or a stripping solution; forming a wiring pattern 13 covering the electrode 11 on the wafer, the wiring pattern made of a metal material that does not dissolve in the developing solution or the stripping solution; forming a post comprising a resist layer that is cured to form an opening 60; individualizing the wafer having the post formed thereon into each semiconductor element 10 while the post is formed; die bonding the semiconductor element 10 on a substrate; electrically connecting the semiconductor element 10 and an external electrode 31 on the substrate; disposing the semiconductor elements 10 and the substrate in a sealing mold, and sealing these with a resin; and removing the post to form the opening 60.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a semiconductor device that is sealed with resin and has an opening in a part thereof, and to the semiconductor device. [Background technology]

[0002] Conventionally, semiconductor devices have been known in which an opening is formed in an encapsulating resin for protecting components such as bonding wires to allow light to enter the light receiving portion of a light receiving element or to allow light emitted by a light emitting element to radiate. As a method for manufacturing such a semiconductor device, Patent Document 1 discloses a method for manufacturing a semiconductor device, which includes the steps of forming a post (first resin film) on a light receiving portion 120 on a wafer or around the light receiving portion 120, pressing an encapsulating mold against the upper surface of the post and the lower surface of a lead frame 180, respectively, and injecting encapsulating resin into the gaps around the post to form an encapsulating resin layer 200 around the post, and removing the post to expose the light receiving element 100 to the outside. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-62232 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when manufacturing a semiconductor device in which a portion of a semiconductor element is exposed through an opening using the method disclosed in Patent Document 1, a resist layer is laminated on the upper surface of a wafer, a portion of the resist layer is hardened by exposure to light, and the unhardened resist layer is removed using an alkaline developer, thereby forming posts on the upper surface of the wafer. Furthermore, unnecessary posts can be removed using an alkaline stripper. However, when a semiconductor element has an electrode on its surface made of a metal composition containing aluminum, zinc, or lead, there is a problem that when the resist layer is removed using an alkaline developer or stripper, the alkaline developer or stripper comes into contact with the aluminum, zinc, or lead used in the electrode and reacts with it, causing the electrode to dissolve (corrode).

[0005] The present invention aims to provide a method for manufacturing a semiconductor device that can appropriately manufacture a semiconductor device in which an electrode made of a metal material that dissolves in a developer or a stripper is arranged on the surface of a semiconductor element, and a semiconductor device manufactured by the manufacturing method. [Means for solving the problem]

[0006] The present invention The first perspective The method for manufacturing a semiconductor device according to the present invention is a method for manufacturing a semiconductor device including a semiconductor element having a functional part disposed in an opening, and includes the steps of: preparing a wafer on which electrodes of the semiconductor element are formed, the electrodes being made of a metal material that dissolves in a developer or a stripper; forming a wiring pattern on the wafer, the wiring pattern being made of a metal material that is not soluble in the developer or the stripper and that covers the electrodes; forming posts made of a hardened resist layer for forming the openings; singulating the wafer on which the posts are formed into individual semiconductor elements with the posts still formed; die-bonding the semiconductor elements onto a substrate; and bonding the semiconductor elements and external electrodes on the substrate together. via the wiring pattern a step of electrically connecting the semiconductor element and the substrate, and placing the semiconductor element and the substrate in a molding die, and filling the space around the outer periphery of the posts with ... Seal Stop Forming the resin sealing part and removing the posts formed on the semiconductor element. To the resin sealing portion Forming the opening By doing so, a part of the wiring pattern is exposed from the resin sealing portion. Process and The electrode is disposed within the opening, and the wiring pattern includes a wiring that extends from inside the opening to outside the opening and covers the electrode disposed within the opening. It is characterized by: a step of forming a wiring pattern on the wafer, the wiring pattern being made of a metal material that is insoluble in the developer and the stripper and that covers the electrodes; a step of forming a resist layer on an area including at least a portion of the electrodes after forming the wiring pattern; a step of hardening a portion of the resist layer; a step of removing the unhardened portion of the resist layer using the developer or the stripper to form posts made of the hardened resist layer; a step of singulating the wafer on which the posts are formed into individual semiconductor elements with the posts still formed; a step of die-bonding the semiconductor elements on which the posts are formed onto a substrate; In the above-described method for manufacturing a semiconductor device, the developing solution or the stripping solution may be alkaline, and the electrode may be made of a metal composition containing aluminum, zinc, or lead. The above-described method for manufacturing a semiconductor device may include, as a pre-step of the step of forming the wiring pattern on the wafer, a step of forming a metal film that covers the electrodes in order to improve adhesion of the wiring. In the above-mentioned method for manufacturing a semiconductor device, the metal film can be formed by vapor deposition or sputtering on the electrode, and the wiring pattern can be formed by plating on the metal film.

[0007] The present invention The first perspective The semiconductor device according to the present invention is a semiconductor device including a semiconductor element having a functional part disposed in an opening, the semiconductor element having an electrode made of a metal material that dissolves in a developer or a stripper on the upper surface thereof. At the same time, a wiring pattern made of a metal material that covers the electrodes and is insoluble in the developing solution and the stripping solution; and a resin sealing portion that seals the semiconductor element except for the opening. The electrode is disposed within the opening, and the wiring pattern covers the electrode and extends from inside the opening to outside the opening. It is characterized by: In the above semiconductor device, the electrodes may be made of a metal composition containing aluminum, zinc, or lead. The semiconductor device may have a metal film covering the electrodes to enhance adhesion of the wiring pattern, and the wiring pattern may be formed on the metal film. In the above semiconductor device, the wiring covering the electrode arranged in the opening may be electrically connected to an external electrode outside the opening by a wire. In the above semiconductor device, the electrode may be arranged outside the opening, and the wiring pattern may be configured to include wiring extending from the electrode arranged outside the opening to a position where the wiring pattern is connected to an external electrode by a wire. In the semiconductor device described above, the opening may be configured to have a substantially circular, elliptical, rectangular or polygonal shape when viewed from above. [Effects of the Invention]

[0008] According to the present invention, in a semiconductor device having a semiconductor element with an electrode made of a metal that dissolves in a resist developer or a resist stripper, it is possible to increase the degree of freedom in the shape of an opening for exposing a functional portion. [Brief explanation of the drawings]

[0009] [Figure 1] 1A is a plan view showing a semiconductor device according to this embodiment, and FIG. 1B is a cross-sectional view taken along line B1-B1 of FIG. [Figure 2] FIG. 1 is a plan view (part 1) for explaining a manufacturing method according to the present embodiment. [Figure 3] FIG. 10 is a plan view (part 2) for explaining the manufacturing method according to the present embodiment. [Figure 4] FIG. 2 is a cross-sectional view (part 1) for explaining the manufacturing method according to the present embodiment. [Figure 5] FIG. 10 is a cross-sectional view (part 2) for explaining the manufacturing method according to the present embodiment. [Figure 6] FIG. 10 is a cross-sectional view (part 3) for explaining the manufacturing method according to the present embodiment. [Figure 7] 1A is a plan view showing a semiconductor device according to a reference example, and FIG. 1B is a cross-sectional view taken along line B2-B2 of FIG. [Figure 8] FIG. 10 is a cross-sectional view showing a semiconductor device according to another embodiment. [Figure 9] FIG. 10 is a cross-sectional view showing a semiconductor device according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of a semiconductor device according to the present invention will be described with reference to the drawings. In practice, a large number of semiconductor devices are fabricated simultaneously using a single wafer, but the following description will be given by taking one of the semiconductor devices as an example.

[0011] <Configuration> FIG. 1(A) is a plan view showing a semiconductor device 1 according to this embodiment, and FIG. 1(B) is a cross-sectional view taken along line B1-B1 in FIG. 1(A). As shown in FIGS. 1(A) and 1(B), the semiconductor device 1 according to this embodiment is formed by sealing a flat-placed semiconductor element 10 with a resin sealing portion 50. The semiconductor device 1 also has an opening 60 for exposing a functional portion of the semiconductor element 10. An example of the semiconductor device 1 is an optical module in which a light-emitting element or a light-receiving element is mounted as the semiconductor element 10.

[0012] 1(A) and 1(B), the semiconductor device 1 has a semiconductor element 10, a metal film 12, rewiring 13, a DAF (Die Attach Film) 14, external electrodes 31, bonding wires 32, a resin sealing portion 50, and an opening 60. Each of these components will be described below.

[0013] An electrode 11 (electrode pad) having a rectangular shape in top view is formed on the top surface of the semiconductor element 10. In this embodiment, the electrode 11 is made of aluminum, but it can also be made of a metal compound containing aluminum or a metal composition containing zinc or lead. The top surface of the semiconductor element 10, including the electrode 11, is covered with a resin encapsulant 50, with an opening 60 provided in the center, through which a functional section 70 on the top surface of the semiconductor element 10 is exposed. The functional section 70 on the top surface of the semiconductor element 10 exposed through the opening 60 is, for example, a light-emitting section of a light-emitting element or a light-receiving section of a light-receiving element. If the semiconductor element 10 is a light-emitting element, light from the light-emitting section is emitted to the outside of the semiconductor device 1 through the opening 60. Alternatively, if the semiconductor element 10 is a light-receiving element, light from the outside of the semiconductor device 1 is incident on the light-receiving section of the semiconductor element 10 through the opening 60. The thickness of the semiconductor element 10 is not particularly limited, but can be, for example, 400 μm.

[0014] The upper and side surfaces of the semiconductor element 10 are covered with a resin encapsulant 50, and the lower surface of the semiconductor element 10 and the lower surface of the resin encapsulant 50 constitute the lower surface of the semiconductor device 1. On the lower surface of the semiconductor device 1, the lower surface of the semiconductor element 10 and the lower surfaces of the external electrodes 31 are exposed from the resin encapsulant 50. The external electrodes 31 are made of, for example, copper. The exposed lower surface of the semiconductor element 10 is covered with a DAF (Die Attach Film) 14. The DAF 14 is made of an insulating material, so the lower surface of the semiconductor element 10 is insulating. Therefore, even if a wiring pattern is routed through the mounting position of the semiconductor device 1 on the mounting surface of the substrate 30 (described below), a short circuit between the wiring pattern and the lower surface of the semiconductor element 10 can be prevented. The DAF 14 can be made of, for example, a 25 μm-thick thermosetting resin. Examples of such thermosetting resins include a mixture of epoxy, silicone, silica, and the like. As shown in FIG. 1(B), the resin sealing portion 50, the DAF 14 (the lower surface of the semiconductor element 10), and the external electrodes 31 that form the lower surface of the semiconductor device 1 are arranged substantially flush (on substantially the same plane).

[0015] In the semiconductor device 1 according to this embodiment, the upper surface of the electrode 11 of the semiconductor element 10 is covered with a metal film 12 and rewirings 13. The metal film 12 is a thin metal film formed by sputtering or vapor deposition of a metal such as titanium or copper, which can strengthen the adhesion of the rewirings 13. The metal film 12 is formed to cover each of the multiple electrodes 11. In this embodiment, the metal film 12 can be formed as a base in the region where the rewirings 13 are to be formed by removing the metal film 12 from the region where the rewirings 13 are to be formed by wet etching or the like. In this embodiment, the metal film 12 is formed to extend from the outside to the inside of the opening 60, as shown in FIG. 1(B).

[0016] The rewiring 13 is formed by forming a metal film 12 on the electrode 11 and then plating the metal film 12 with copper or other plating material. In this embodiment, after forming the metal film 12 over the entire upper surface of a wafer from which multiple semiconductor elements 10 are obtained, a first resist layer 20 is formed using a dry film resist or the like. Exposure and development are then performed to form a wiring pattern of the rewiring 13 (hereinafter referred to as the "rewiring pattern"), exposing portions of the metal film 12 in accordance with the rewiring pattern. The exposed metal film 12 is then plated with electrolytic plating or other plating material to form the rewiring 13, and the hardened resist layer 21 is then removed. Further, the metal film 12 in areas other than the rewiring pattern is removed by etching, thereby forming the rewiring pattern of the rewiring 13, as shown in FIGS. 1B and 2B. The rewiring pattern of this embodiment is composed of rewirings 13a to 13d, as shown in FIG. 2B. Of these, the rewiring 13b is formed so as to extend from the outside to the inside of the opening 60, as shown in FIGS. 1B and 2C.

[0017] 3(D), the rewirings 13a to 13d are each connected to an external electrode 31 provided on the substrate 30 by a bonding wire 32. By connecting the rewirings 13a to 13d to the external electrodes 31a to 31c, 31f by the bonding wire 32, the electrodes 11 of the semiconductor element 10 are electrically connected to the external electrodes 31. Note that in the example of FIG. 3, the external electrodes 31d and 31e are not used, but if the external electrode 31d is used, for example, the rewiring pattern may be such that the rewiring 13d extends in a direction approaching the external electrode 31d.

[0018] The semiconductor element 10, bonding wires 32, and external electrodes 31 arranged on the substrate 30 are sealed with a resin sealing portion 50 and then separated from the substrate 30. The opening 60 is not sealed with the resin sealing portion 50, and a functional portion 70 provided on the upper surface of the semiconductor element 10 is exposed through the opening 60. For example, epoxy resin used for sealing is known to lose its light transmission characteristics as it deteriorates, but because the opening 60 is hollow, this problem does not occur. The resin sealing portion 50 can be made of, for example, a black epoxy resin containing a light-blocking filler.

[0019] <Manufacturing method> Next, a method for manufacturing the semiconductor device 1 according to this embodiment will be described with reference to FIGS. 2 to 6. FIGS. 2 and 3 are plan views illustrating the method for manufacturing the semiconductor device 1 according to this embodiment, and FIGS. 4 to 6 are cross-sectional views illustrating the method for manufacturing the semiconductor device 1 according to this embodiment. FIG. 4(A) is a cross-sectional view taken along line 4A-4A in FIG. 2(A), FIG. 5(H) is a cross-sectional view taken along line 5H-5H in FIG. 2(B), and FIG. 5(K) is a cross-sectional view taken along line 5K-5K in FIG. 2(C). FIG. 6(L) is a cross-sectional view taken along line 6L-6L in FIG. 3(D), and FIG. 6(N) is a cross-sectional view taken along line 6N-6N in FIG. 3(E). Furthermore, the semiconductor elements 10 are obtained by dicing a wafer, and Figures 2(A) to (C), 4(A) to (E), and 5(F) to (K) show the process before dicing the semiconductor elements 10, but for ease of explanation, in the following, the area corresponding to one semiconductor element 10 on the wafer before dicing will be described as the semiconductor element 10.

[0020] First, a wafer having areas corresponding to a plurality of semiconductor elements 10 is prepared. As shown in Fig. 4(A), an electrode formation step is carried out to form a plurality of electrodes 11 on the upper surface of each of the regions corresponding to the plurality of semiconductor elements 10. In this embodiment, as shown in Fig. 2(A), a wafer is prepared on which four electrodes 11a to 11d are formed in a region corresponding to one semiconductor element 10. Next, as shown in FIG. 4(B), a metal film formation process is carried out to form a thin metal film 12 made of a metal composition containing a metal other than aluminum, zinc, or lead (preferably copper or titanium) on the entire upper surface of the semiconductor element 10 by sputtering or vapor deposition.

[0021] Next, as shown in FIG. 4(C), a first resist layer forming step is carried out in which a resist such as a dry film is applied on the metal film 12 to form a first resist layer 20. 4(D), a resist hardening step is carried out in which the first resist layer 20 in areas other than the areas corresponding to the rewiring pattern of the rewiring 13 is exposed to light and hardened. In FIG. 4(D), the hardened resist layer (hereinafter referred to as the "hardened resist layer") is indicated by the reference numeral 21. Next, as shown in Fig. 4(E), a first resist layer removal step is performed in which the uncured first resist layer 20 is removed with a developer. Here, since the metal film 12 covering the electrode 11 is formed in the metal film formation step (Fig. 4(B)), the developer does not come into contact with the electrode 11 in the first resist layer removal step, and dissolution (corrosion) of the electrode 11 by the developer can be prevented. Note that even when the first resist layer removal step is performed, the cured resist layer 21 is not removed.

[0022] The developer according to this embodiment is an alkaline aqueous solution, and examples thereof include alkaline aqueous solutions containing alkaline agents such as inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; primary amines such as ethylamine and n-propylamine; secondary amines such as diethylamine and di-n-butylamine; tertiary amines such as triethylamine and methyldiethylamine; alcohol amines such as dimethylethanolamine and triethanolamine; tetraalkylammonium hydroxides such as dimethylbis(2-hydroxyethyl)ammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, ethyltrimethylammonium hydroxide, butyltrimethylammonium hydroxide, methyltriamylammonium hydroxide, and dibutyldipentylammonium hydroxide; quaternary ammonium salts such as trimethylphenylammonium hydroxide, trimethylbenzylammonium hydroxide, and triethylbenzylammonium hydroxide; and cyclic amines such as pyrrole and piperidine. The alkaline aqueous solution may also be used by adding an appropriate amount of alcohols and surfactants. The concentration of the alkaline agent in the alkaline developer is preferably 0.001 to 20% by mass, more preferably 0.01 to 10% by mass, and even more preferably 0.1 to 1% by mass. The pH of the alkaline developer is preferably 10.0 to 15.0. The alkaline agent concentration and pH of the alkaline developer can be adjusted as appropriate. The alkaline developer may be used by adding an appropriate amount of a water-soluble organic solvent such as methanol or ethanol, a surfactant, etc.

[0023] The developing method is not particularly limited, and for example, dip (immersion) development or spray development can be used depending on the type of dry film resist. The reaction temperature between the first resist layer 20 and the developer can also be set appropriately. In this embodiment, the first resist layer 20 (drum film resist) has a crosslinked structure of a resin having a carboxyl group in its side chain, and the carboxyl group of the first resist layer 20 reacts with the developer to dissolve the first resist layer 20. After development, the resist is preferably thoroughly washed with a dedicated rinse or pure water, and then dried by spin drying using a spin dryer or the like.

[0024] Next, a rewiring process is carried out in which a plating process is performed on the rewiring pattern portion where the metal film 12 is exposed, and a rewiring pattern is formed in which rewiring 13 is laminated on the metal film 12, as shown in Fig. 5(F). The plating process is carried out using a metal composition containing a metal other than aluminum, zinc, and lead (preferably copper). Subsequently, a hardened resist layer removal step is carried out to remove the remaining hardened resist layer 21. The method for removing the hardened resist layer 21 is not particularly limited, and may be, for example, a method using a plasma asher or an ozone asher to remove the hardened resist layer 21 from the semiconductor element 10, or a method using a wet station to remove the hardened resist layer 21 from the semiconductor element 10 with a specific chemical solution (e.g., a commercially available resist stripper). As a result, as shown in FIG. 5(G), only the metal film 12 and the rewiring 13 are stacked on the semiconductor element 10. In this embodiment, since the electrodes 11 are covered with the metal film 12 and the rewiring 13, an alkaline stripper may also be used as the resist stripper. Next, a metal film removal step is carried out in which the metal film 12 formed on the entire upper surface of the semiconductor element 10 is etched to remove unnecessary metal film 12. As a result, as shown in Figures 2(B) and 5(H), the metal film 12 is formed only in the region where the rewiring pattern of the rewiring 13 is formed, and the upper surface of the semiconductor element 10 is exposed in other regions.

[0025] Next, as shown in FIG. 5(I), a dry film resist is again applied to the upper surface side of the semiconductor element 10, and a second resist layer forming step is carried out to form a second resist layer 22. Next, a post forming step is carried out in which a region of the second resist layer 22 that will become the periphery of the opening 60 is exposed to light and hardened to form the post 23. In this embodiment, as shown in FIG. 5(J), a square frame-shaped closed post 23 that crosses a part of the rewiring 13 is formed (see FIG. 2(C)). Next, a second resist layer removal process is performed in which the unhardened second resist layer 22 is developed and removed with a developer. As a result, only the posts 23 and the rewiring pattern remain on the upper surface of the semiconductor element 10, as shown in Figures 2(C) and 5(K). Even in the second resist layer removal process, the electrodes 11 are covered with the metal film 12 and the rewiring 13, so dissolution (corrosion) of the electrodes 11 by the developer can be prevented.

[0026] Next, a singulation step is carried out in which the wafer is diced to separate the semiconductor elements 10 into individual pieces. 3(D) and 6(L), a step of die-bonding the separated semiconductor element 10 to the upper surface of a stainless steel substrate 30 is then carried out. In this embodiment, by using a DAF 14, it is possible to die-bond the semiconductor element 10 to a predetermined position on the upper surface of the substrate 30. In the die-bonding step, a plurality of external electrodes 31a to 31f are also placed at predetermined positions on the substrate 30, and the external electrodes 31a to 31f are electrically connected to the rewirings 13 by bonding wires 32.

[0027] Next, as shown in FIG. 6(M), a resin sealing process is performed in which the semiconductor element 10 and external electrodes 31 mounted on the substrate 30 are housed together with the substrate 30 in a sealing mold 40 and sealed with resin. In the resin sealing process, the posts 23 established on the upper surface of the semiconductor element 10 are pressed against the lower surface of the substrate 30 in the sealing mold 40, while sealing resin is filled into the gaps around the closed posts 23 and cured, thereby forming a resin sealing portion 50 by transfer molding. Note that, as shown in FIG. 6(M), the space inside the posts 23 becomes an opening 60 that is not filled with sealing resin. After the resin sealing portion 50 is formed, the sealing mold 40 is removed.

[0028] Next, a post removal step is performed to remove the posts 23. By removing the substrate 30, the semiconductor device 1 is manufactured as shown in FIGS. 3(E) and 6(N). Note that, like the hardened resist layer 21, the posts 23 can be removed using a specific agent (such as a commercially available stripping solution). Note that, in this embodiment, since the electrodes 11 are covered with the metal film 12 and the rewiring 13, an alkaline stripping solution can also be used as the resist stripping solution for the posts 23. Furthermore, when manufacturing the semiconductor device 1, as shown in FIG. 6(O), the resin sealing portion 50 can be cut as appropriate so that the planar area of ​​the semiconductor device 1 has a predetermined size.

[0029] As described above, in the semiconductor device 1 according to this embodiment, a metal film 12 made of a developer-insoluble metal material (a metal composition other than aluminum, zinc, and lead) is formed by sputtering or vapor deposition on an electrode 11 made of a developer-soluble metal material (a metal composition containing aluminum, zinc, or lead) formed on the surface of a semiconductor element 10. Then, a rewiring 13 made of a developer-insoluble metal material (a metal composition other than aluminum, zinc, and lead) is formed on the metal film 12 by plating. A second resist layer 22 is then formed in an area including the top surface of the rewiring 13. Part of the second resist layer 22 is exposed to light and cured, and the uncured second resist layer 22 is removed with an alkaline developer, thereby forming posts 23 for forming openings 60. Furthermore, gaps around the outer periphery of the posts 23 are sealed with resin to form resin-sealed portions 50. The posts 23 are then removed to form openings 60. As described above, in the semiconductor device 1 according to this embodiment, the electrode 11 made of a metal composition containing aluminum, zinc, or lead is covered with the metal film 12 and the rewiring 13 made of a metal composition containing a metal other than aluminum, zinc, and lead. Therefore, even when the resist layers 20 and 22 are subsequently removed using an alkaline developer, or when the cured resist layer 21 or the post 23 is subsequently removed using an alkaline stripper, the alkaline developer or stripper can be prevented from coming into contact with the electrode 11, thereby preventing dissolution of the electrode 11 by the developer or stripper. Since there is no need to worry about dissolution of the electrode 11 by the developer or stripper, there is no need to use an expensive material such as gold, which is insoluble in the developer or stripper.

[0030] 3(D) and 5(K), in the semiconductor device 1 according to this embodiment, the rewirings 13a to 13d can be formed not only on the electrodes 11a to 11d but also on the rewiring 13b extending from the inside to the outside of the closed post 23. This makes it possible to ensure a sufficiently wide opening 60 regardless of the position of the electrode 11 (for example, even when an electrode is provided inside the opening 60 like the electrode 11b), thereby increasing the degree of freedom in designing the semiconductor device 1.

[0031] Fig. 7(A) is a plan view showing a semiconductor device 1a according to a reference example, and Fig. 7(B) is a cross-sectional view taken along line B2-B2 in Fig. 7(A). In the semiconductor device 1a according to the reference example, the rewiring 113 is formed in the same wiring pattern as the electrode 11. In the following, the same elements as those in the above-described embodiment are denoted by the same reference symbols, and description thereof will be omitted. When the rewiring 113 is formed only on the electrode 11, as shown in FIGS. 7A and 7B, the entire rewiring 113 must be sealed with a resin sealing portion 50 to protect the bonding wire 32 bonded to the rewiring 113. Therefore, an opening must be shaped so that the sealing resin can reach the rewiring 113 during transfer molding. In the reference example, as shown in FIG. 7A, the opening 160 is U-shaped or concave in top view, which enables the rewiring 113 located in the center to be sealed with resin. In contrast, in the semiconductor device 1 according to this embodiment, even when the electrode is located in the center, the rewiring 13b for electrically connecting to the central electrode 11b can extend from the inside to the outside of the opening 60, thereby increasing the flexibility in the shape of the opening 60. Therefore, the shape of the opening 60 can be, for example, a polygon, a polygon with an even number of vertices, a circle, or an ellipse.

[0032] Furthermore, the semiconductor device 1 according to this embodiment can increase the degree of freedom in the position of the electrodes 11 on the semiconductor element 10. That is, in a semiconductor device without rewiring 13, the position of the electrodes 11 on the semiconductor element 10 may be limited depending on the final form of the semiconductor device. However, in the semiconductor device 1 according to this embodiment, the electrodes 11 are covered with a rewiring pattern, so the layout can be easily changed by changing the rewiring pattern without changing the electrode positions on the semiconductor element. Furthermore, in the semiconductor device 1 according to this embodiment, even if the area of ​​the electrodes 11 is small, the workability of wire bonding can be improved by increasing the area of ​​the rewiring 13 or routing it.

[0033] Although the preferred embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the above-described embodiments. Various modifications and improvements can be made to the above-described embodiments, and such modifications and improvements are also included in the technical scope of the present invention.

[0034] For example, in the above-described embodiment, the opening 60 has a rectangular shape, but is not limited to this, and the opening 60 may have a circular or polygonal shape.

[0035] In the above-described embodiment, the rewirings 13 extend from the inside of the opening 60 where the electrodes 11 are disposed to the outside of the opening 60 as shown in FIGS. 1A and 1B, and the rewirings 13 are formed only on the electrodes 11 disposed outside the opening 60 as shown in FIGS. 7A and 7B. However, the present invention is not limited to these configurations. For example, as shown in FIG. 8, the electrodes 11 may be formed outside the opening 60, and the rewirings 13 covering the electrodes 11 may extend from the outside of the opening 60 toward the inside of the opening 60 or along the periphery of the opening 60 within the region outside the opening 60. By routing the rewirings 13 outside the opening 60 in this way, the position where wire bonding is performed on the rewirings 13 can be freely changed (because wire bonding is not restricted to the position of the electrodes 11 on the semiconductor element 10), thereby increasing the degree of freedom in design. FIG. 8 is a cross-sectional view showing a semiconductor device 1b according to another embodiment.

[0036] Furthermore, in the above-described embodiment, as shown in Fig. 1(B), a configuration in which the underside of the semiconductor element 10 is covered with the DAF 14 has been exemplified, but the present invention is not limited to this configuration, and as shown in Fig. 9, a configuration in which the semiconductor element 10 is bonded and mounted on the upper surface of the die pad 15 may also be used. In this case, the semiconductor element 10 is bonded onto the die pad 15 with an insulating or conductive adhesive, and the back surface of the die pad is exposed from the resin sealing portion. Fig. 9 is a cross-sectional view showing a semiconductor device 1c according to another embodiment. [Explanation of symbols]

[0037] 1, 1a to 1c...Semiconductor device 10...Semiconductor element 11...Electrode 12...Metal film 13…Rewiring 14...DAF 15...Die pad 20...Resist layer 21...hardened resist layer 22...Resist layer 31...External electrode 32...Bonding wire 50…Resin sealing part 60...Opening 23...Post 30...Substrate 40...Mold for sealing 70...Functional part

Claims

1. A method for manufacturing a semiconductor device including a semiconductor element having a functional portion disposed in an opening, the method comprising: preparing a wafer on which electrodes of the semiconductor element are formed, the electrodes being made of a metal material that dissolves in a developing solution or a stripping solution; forming a wiring pattern on the wafer, the wiring pattern being made of a metal material that is insoluble in the developing solution and the stripping solution and covering the electrodes; forming a post made of a hardened resist layer to form the opening; a step of dividing the wafer on which the posts are formed into individual semiconductor elements while the posts remain formed; die-bonding the semiconductor element having the posts formed thereon onto a substrate; a step of electrically connecting the semiconductor element and an external electrode on the substrate via the wiring pattern; a step of placing the semiconductor element and the substrate in a molding die and forming a resin molding portion that seals a space on an outer periphery of the post; removing the post formed on the semiconductor element and forming the opening in the resin sealing portion to expose a part of the wiring pattern from the resin sealing portion; the electrode is disposed within the opening; The method for manufacturing a semiconductor device, wherein the wiring pattern includes wiring that extends from inside the opening to outside the opening and covers an electrode disposed in the opening.

2. A method for manufacturing a semiconductor device including a semiconductor element having a functional portion disposed in an opening, comprising: preparing a wafer on which electrodes of the semiconductor element are formed, the electrodes being made of a metal material that dissolves in a developing solution or a stripping solution; forming a wiring pattern on the wafer, the wiring pattern being made of a metal material that is insoluble in the developing solution and the stripping solution and covering the electrodes; forming a resist layer on an area including at least a portion of the electrode after forming the wiring pattern; curing a portion of the resist layer; removing uncured portions of the resist layer using the developer or the stripper to form posts made of the cured resist layer; a step of dividing the wafer on which the posts are formed into individual semiconductor elements while the posts remain formed; die-bonding the semiconductor element having the posts formed thereon onto a substrate; a step of electrically connecting the semiconductor element to an external electrode on the substrate; a step of placing the semiconductor element and the substrate in a molding die and sealing the space on the outer periphery of the posts with resin; removing the post formed on the semiconductor element to form the opening.

3. the developer or the stripper is alkaline, 3. The method for manufacturing a semiconductor device according to claim 1, wherein the electrode is made of a metal composition containing aluminum, zinc, or lead.

4. 4. The method for manufacturing a semiconductor device according to claim 1, further comprising the step of forming a metal film covering said electrodes in order to improve adhesion of said wiring pattern as a pre-step of the step of forming said wiring pattern on said wafer.

5. the metal film is formed on the electrode by vapor deposition or sputtering; 5. The method for manufacturing a semiconductor device according to claim 4, wherein the wiring pattern is formed by plating the metal film.

6. A semiconductor device including a semiconductor element having a functional part disposed in an opening, the semiconductor element has, on its upper surface, an electrode made of a metal material that dissolves in a developing solution or a stripping solution, and a wiring pattern that covers the electrode and is made of a metal material that is not dissolved in the developing solution or the stripping solution; a resin sealing portion that seals the semiconductor element except for the opening, the electrode is disposed within the opening; The semiconductor device is characterized in that the wiring pattern extends from inside the opening to outside the opening.

7. The semiconductor device according to claim 6 , wherein the electrode is made of a metal composition containing aluminum, zinc, or lead.

8. 8. The semiconductor device according to claim 6, further comprising a metal film covering said electrodes to enhance adhesion of said wiring pattern, said wiring pattern being formed on said metal film.

9. 9. The semiconductor device according to claim 6, wherein a wiring covering the electrode disposed in said opening is connected to an external electrode by a wire outside said opening.

10. the electrode is disposed outside the opening, 10. The semiconductor device according to claim 6, wherein said wiring pattern includes a wire extending from an electrode disposed outside said opening to a position where said wiring pattern is connected to an external electrode by a wire.

11. 11. The semiconductor device according to claim 6, wherein the opening has a substantially circular, elliptical, rectangular or polygonal shape when viewed from above.

Images