JP5026828B2 - Electronic component and manufacturing method thereof - Google Patents

Description

  The present invention relates to an electronic component and a manufacturing method thereof, and more particularly to an electronic component having a wafer level package structure and a manufacturing method thereof.

  In recent years, in response to the demand for downsizing of electronic components, a wafer level package that protects an element by providing a resin on the substrate so as to cover the element provided on the substrate, and uses the resin as a substitute for the package. (Hereinafter referred to as WLP) structure has been developed. FIG. 1 is a sectional view of an electronic component (conventional example 1) having a typical WLP structure. Referring to FIG. 1, an element 12 is provided on a substrate 10. An electrode 14 that is electrically connected to the element 12 is provided on the substrate 10. A resin 16 is provided on the substrate 10 so as to cover the element 12. A through electrode 18 that penetrates the resin 16 is provided on the electrode 14. A solder ball 20 is provided on the through electrode 18. Thus, the element 12 and the solder ball 20 are electrically connected via the through electrode 18 and the electrode 14, and when the electronic component is flip-chip mounted, the through electrode 18 and the solder ball 20 bring the electronic component to the outside. Functions as a terminal part to be electrically connected.

  In addition, as one of acoustic wave devices using elastic waves, there is provided a comb electrode made of IDT (Interdigital Transducer) formed on the surface of a piezoelectric substrate, and an elastic wave excited by applying electric power to the comb electrode Surface acoustic wave devices using are well known. Furthermore, recently, an acoustic wave device using a piezoelectric thin film resonator (FBAR: Film Bulk Acoustic Resonator) that forms a pair of electrodes on the front and back sides of a piezoelectric thin film and uses thickness vibration thereof has been developed. In order to maintain the characteristics of the acoustic wave element, these acoustic wave devices have a functional portion of the acoustic wave element (surface acoustic wave element: IDT electrode finger, piezoelectric thin film resonator element: region where the upper and lower electrodes sandwiching the piezoelectric thin film overlap) It is necessary to provide a cavity above. FIG. 2 is a sectional view of a surface acoustic wave device (conventional example 2) having a WLP structure. Referring to FIG. 2, an element 12 that is a surface acoustic wave element including a comb electrode and a reflector is provided on a substrate 10. Resin 16 having a second cavity 22 is provided on the functional portion of element 12. Other configurations are the same as those of the first conventional example and are shown in FIG.

  One method for forming the through electrode 18 is to fill a through hole formed on the electrode 14 that penetrates the resin 16 with solder paste or the like using squeegee printing. Conventional Example 1 and Conventional Example 2 have a structure in which the through hole is closed in the depth direction. For this reason, when solder paste or the like is filled in the through hole by squeegee printing, the air in the through hole has no escape path and is confined in the through hole, and a void is generated in the through hole.

Patent Document 1 discloses a technique for solving this problem. FIG. 3 shows a cross-sectional view of a surface acoustic wave device (conventional example 3) according to Patent Document 1. In FIG. With reference to FIG. 3, a hole portion 24 penetrating from the side surface of the through electrode 18 to the surface of the resin 16 is provided in one direction. The other configuration is the same as that of the conventional example 2 and is shown in FIG. According to Conventional Example 3, since the hole 24 that penetrates from the side surface of the through electrode 18 to the surface of the resin 16 is provided, if the through hole is filled with solder paste or the like by squeegee printing, the hole 24 becomes air. It can function as an escape route and can suppress the generation of voids in the through holes.
JP 10-48244 A

  First, FIG. 4 shows a cross-sectional view for explaining a problem in the case where the through hole 26 is filled with the solder paste by squeegee printing in the surface acoustic wave device according to the second conventional example. In FIG. 4, a cross-sectional view before individually dicing the surface acoustic wave device according to Conventional Example 2 is shown (the cross-sectional views before dicing are also shown in FIGS. 5, 13 and 15). Yes. Referring to FIG. 4, since the through hole 26 has a structure of a space closed in the depth direction, when the through hole 26 is filled with solder paste by squeegee printing using the squeegee 48, The air is confined without a passage, and a void 28 is generated in the through hole 26. The void 28 is likely to occur in a specific direction related to the direction of squeegee printing and the shape of the through hole 26. In order to suppress the generation of the voids 28, squeegee printing may be performed in a vacuum. However, since the substrate 10 is evacuated, the manufacturing efficiency is lowered and an expensive apparatus is required.

  Next, FIG. 5 shows a cross-sectional view for explaining a problem in the case where the through hole 26 is filled with the solder paste by squeegee printing in the surface acoustic wave device according to Conventional Example 3. Referring to FIG. 5, when the solder paste is filled in the through hole 26 by squeegee printing using the squeegee 48, if the solder paste is filled in the hole 24 before the through hole 26, The air passage is blocked. For this reason, the air in the through hole 26 is confined, and a void 28 is generated in the through hole 26.

  Usually, the surface acoustic wave devices 25 are collectively formed on a substrate 10 in a wafer state as shown in FIG. 6, and a plurality of surface acoustic wave devices 25 formed on the wafer are respectively separated by dicing regions. Separated into one. In other words, the process of filling the through holes 26 with the solder paste by squeegee printing is also performed collectively on the substrate 10 in the wafer state. In general, squeegee printing is reciprocated in order to improve manufacturing efficiency and solder paste filling. If the hole 24 is provided only in one direction as in the conventional example 3, the hole 24 is filled with solder paste before the through hole 26. Therefore, in the conventional example 3, since the hole 24 is not filled with solder paste, squeegee printing is performed only in one direction, or the hole 24 is covered with a mask or the like to perform squeegee printing back and forth. There must be. For this reason, it is difficult in Conventional Example 3 to form the through electrode 18 with high manufacturing efficiency.

  The present invention has been made in view of the above problems, and provides an electronic component capable of suppressing the amount of voids generated in a through hole and capable of forming a through electrode with high production efficiency, and a method for producing the same. The purpose is to do.

The present invention provides an element provided on a substrate, an electrode provided on the substrate and electrically connected to the element, a resin provided on the substrate so as to cover the element, and the electrode provided, anda through electrode penetrating through the resin, the resin will have a first hollow portion provided to extend in two or more directions from the side surface of the through electrode, the first cavity portion An upper surface and a lower surface of the electronic component are covered with the resin . According to the present invention, since the first cavity functions as an air hole, the amount of voids generated in the through hole can be suppressed. In addition, even if squeegee printing is performed from two or more directions where the first cavity is provided, the amount of voids generated in the through hole can be suppressed, so that the through electrode can be formed with high manufacturing efficiency. it can.

  The said structure WHEREIN: The said 1st cavity part can be set as the structure covered with the said resin. According to this configuration, even if squeegee printing is performed on the resin, the first cavity portion is not blocked, so that a mask or the like does not have to be used for squeegee printing. For this reason, a through electrode can be formed with high manufacturing efficiency.

  In the above configuration, at least two of the first cavities may be provided so as to be symmetric with respect to the through electrode. According to this configuration, since the squeegee printing can be performed in a reciprocating manner, the through electrode can be formed with high manufacturing efficiency.

  The said structure WHEREIN: The said 1st cavity part can be set as the structure provided so that the side surface of the said penetration electrode may be surrounded. According to this configuration, it is possible to suppress the amount of voids generated in the through-holes regardless of the direction of 360 ° squeegee printing.

  The said structure WHEREIN: The said 1st cavity part can be set as the structure penetrated from the side surface of the said penetration electrode to the end surface of the said resin. According to this configuration, since the effect of the first cavity portion as an air hole is further increased, the amount of voids generated in the through hole can be further suppressed.

  In the above-described configuration, the end face of the resin provided above the first cavity is provided closer to the peripheral side of the substrate than the end face of the resin provided below the first cavity. can do. According to this configuration, the effect of the first cavity portion as an air hole is further increased. For this reason, the generation amount of the void generated in the through hole can be further suppressed.

  The said structure WHEREIN: The said penetration electrode can be set as the structure which consists of an electroconductive material which has either Cu, Sn, and Pb as a main component. In the above structure, the substrate may be a piezoelectric substrate, the element may be an acoustic wave element, and the resin may have a second cavity on a functional portion of the acoustic wave element.

  The present invention includes a step of forming an element and an electrode electrically connected to the element on a substrate, and forming a first resin film covering the element and having a first opening on the electrode on the substrate. A second resin having a second opening on the first opening and a fourth opening extending in two or more directions from a side surface of the second opening on the first resin film. A step of forming a film, and a through-hole that includes the first opening, the second opening, and the third opening and penetrates the first resin film, the second resin film, and the third resin film is formed. The third resin film having the third opening on the second opening is formed on the second resin film so that the fourth opening becomes the first cavity. And a step of forming a through electrode on the electrode by filling the through hole with a conductive material. A method of manufacturing an electronic component according to claim Rukoto. According to the present invention, the through hole and the first cavity can be easily formed.

  In the above configuration, the step of forming the first resin film includes the step of forming the first resin film having a fifth opening on the functional portion of the element, and the step of forming the second resin film includes Forming the second resin film having a sixth opening on the fifth opening, and the step of forming the third resin film includes the step of forming the fifth opening and the sixth opening. It can be set as the structure including the process of forming the said 3rd resin film so that it may become a 2 cavity part. According to this configuration, the second cavity can be easily formed.

  In the above configuration, the step of forming the through electrode may be a step of forming the through electrode by filling the through hole with a conductive material by squeegee printing.

  According to the present invention, there is provided an element on the substrate and an electrode electrically connected to the element, the step of forming a resin on the substrate so as to cover the element, and the resin penetrating through the electrode A through-hole is formed on the electrode by forming a through-hole and a first cavity extending in two or more directions from the side surface of the through-hole, and filling the through-hole with a conductive material by squeegee printing. And a process for producing an electronic component. According to the present invention, when the through electrode is formed in the through hole by squeegee printing, the amount of voids generated in the through hole can be suppressed.

  According to the present invention, the first cavity portion functions as an air hole in the through hole, and even if squeegee printing is performed from two or more directions in which the first cavity portion is provided, The amount of voids generated can be suppressed. For this reason, a through electrode can be formed with high manufacturing efficiency.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 7A is a top view of the surface acoustic wave device according to the first embodiment, and FIG. 7B is a cross-sectional view taken along a line AA in FIG. 7A, the substrate 10, the element 12, the wiring 32, the first cavity portion 34, and the second cavity portion 22 are illustrated through the resin 16, and the solder ball 20 is not illustrated (hereinafter referred to as “the solder ball 20”). The same applies to Example 2 to Example 4.

Referring to FIGS. 7A and 7B, on the surface of the substrate 10 which is a piezoelectric substrate made of, for example, LiNbO ₃ (lithium niobate) or LiTaO ₃ (lithium tantalate), for example, Al (aluminum) or Cu An element 12 which is a surface acoustic wave element made of an IDT and a reflector formed of a metal film made of (copper) or the like, and a wiring 32 are provided. An electrode 14 made of, for example, Ni (nickel) is provided on the substrate 10. The element 12 and the electrode 14 are electrically connected via a wiring 32. A second cavity 22 having a height of about 30 μm is provided on the functional portion of the element 12 on the substrate 10, and a resin 16 that is an epoxy resin having a height of about 50 μm is provided so as to cover the element 12 and the wiring 32. . A through electrode 18 having a diameter of about 100 μm that penetrates the resin 16 is provided on the electrode 14. The through electrode 18 is formed of, for example, a solder paste. A first cavity 34 having a height of 20 μm and a width of 50 to 100 μm covered with the resin 16 is provided on the side surface of the through electrode 18 so as to extend in two directions so as to be symmetric with respect to the through electrode 18. Further, the first cavity 34 is provided near the bottom surface of the through electrode 18. A solder ball 20 is provided on the through electrode 18. Thereby, the element 12 and the solder ball 20 are electrically connected via the wiring 32, the electrode 14 and the through electrode 18, and the through electrode 18 and the solder ball 20 are used when the surface acoustic wave device is flip-chip mounted. It functions as a terminal portion for electrically connecting the element 12 to the outside.

  A method for manufacturing the surface acoustic wave device according to the first embodiment will be described with reference to FIGS. FIG. 8A to FIG. 10D are cross-sectional views corresponding to FIG. 7B. FIGS. 8A to 10D show a manufacturing process performed using the substrate 10 in the wafer state, and there are a plurality of areas to be surface acoustic wave devices on the wafer. A region to be a surface acoustic wave device among the surface acoustic wave devices will be illustrated and described. In FIG. 10D, a plurality of surface acoustic wave devices formed on the wafer are separated into one by separating them at a dicing region around the substrate 10.

Referring to FIG. 8A, for example, a metal film made of Al or Cu or the like is formed on the surface of a substrate 10 which is a piezoelectric substrate made of LiNbO ₃ or LiTaO ₃ or the like, and elements 12 and wirings 32 that are surface acoustic wave elements. (Not shown). Further, an electrode 14 made of, for example, Ni or the like and electrically connected to the element 12 via a wiring 32 (not shown) is formed on the substrate 10. Referring to FIG. 8B, a first resin film 36 made of, for example, a negative photosensitive epoxy resin is applied on the substrate 10 by a spin coating method and baked. Referring to FIG. 8C, using a mask, ultraviolet rays (UV light) other than the region where the second cavity 22 on the functional portion of the element 12 is to be formed and the region where the through hole 26 on the electrode 14 is to be formed. Irradiate the first resin film 36 in the region. Referring to FIG. 8D, the first resin film 36 is removed by developing the first resin film 36 so as to remove the first resin film 36 in the region not irradiated with ultraviolet rays (UV light). As a result, a fifth opening 45 is formed in a region to be the second cavity 22 on the functional portion of the element 12, and a first opening 38 is formed in a region to be the through hole 26 on the electrode 14. Is done. The first resin film 36 is cured by heat treatment at 200 ° C. for 1 hour in a nitrogen atmosphere.

  Referring to FIG. 9A, the second resin film 42 made of, for example, a negative photosensitive epoxy resin in the form of a film applied to the protective film 40 so as to hold the first opening 38 and the fifth opening 45. Is pressed and pasted using a pressing roll 44 such as a laminator so as to have a thickness of 20 μm. Referring to FIG. 9B, using a mask, ultraviolet rays (UV light) are formed in a region where the second cavity 22 on the functional portion of the element 12 is to be formed, a region where the through hole 26 is formed on the electrode 14, and Irradiate the second resin film 42 in a region other than the region where the first cavity 34 is to be formed. Referring to FIG. 9C, the protective film 40 is peeled off and developed to remove the second resin film 42 in the region not irradiated with ultraviolet rays (UV light). As a result, a sixth opening 47 is formed on the fifth opening 45 on the functional portion of the element 12, a second opening 39 is formed on the first opening 38 on the electrode 14, and the second opening A fourth opening 43 extending in two directions is formed on the side surface of 39. The second resin film 42 is cured by heat treatment at 200 ° C. for 1 hour in a nitrogen atmosphere. Referring to FIG. 9 (d), the protective film 40 is applied so as to hold the first opening 38, the second opening 39, the fourth opening 43, the fifth opening 45, and the sixth opening 47. The third resin film 46 made of, for example, a negative photosensitive epoxy resin is pressed and pasted using a pressing roll 44 such as a laminator so as to have a thickness of about 20 μm. As a result, the fourth opening 43 becomes the first cavity 34, and the fifth opening 45 and the sixth opening 47 become the second cavity 22.

  Referring to FIG. 10A, the mask is used to irradiate the third resin film 46 in a region other than the region where the through hole 26 is to be formed on the electrode 14 with ultraviolet rays (UV light). Referring to FIG. 10B, the protective film 40 is peeled off and developed to remove the third resin film 46 in the region not irradiated with ultraviolet rays (UV light). As a result, a third opening 41 is formed on the second opening 39 on the electrode 14. Therefore, the first opening 38, the second opening 39, and the third opening 41 are formed on the electrode 14 and penetrate the resin 16 including the first resin film 36, the second resin film 42, and the third resin film 46. A through hole 26 is formed. The third resin film 46 is cured by heat treatment at 200 ° C. for 1 hour in a nitrogen atmosphere. With reference to FIG. 10C, squeegee printing using a squeegee 48 is performed on the resin 16, so that, for example, a solder paste is filled in the through-hole 26 to form the through-electrode 18. Referring to FIG. 10D, a solder ball 20 is formed on the through electrode 18 by mounting, for example, a SnAg solder ball or mask printing and reflowing SnAg solder paste. Thereafter, the substrate 10 in a wafer state in the dicing area is cut and separated by dicing. Thus, the surface acoustic wave device according to Example 1 is completed.

  According to the first embodiment, as shown in FIGS. 7A and 7B, the first cavity 34 that extends in two directions from the side surface of the through electrode 18 is provided. For this reason, as shown in FIG. 10C, even if the through electrode 18 is formed by filling the through hole 26 with solder paste by squeegee printing, the first cavity 34 serves as an air hole in the through hole 26. Since it functions, the generation amount of the void 28 generated in the through hole 26 can be suppressed. Therefore, in the conventional example 2 shown in FIG. 4, the generation amount of the voids 28 cannot be suppressed unless the squeegee printing is performed in a vacuum, but in the first embodiment, the squeegee printing is not performed in a vacuum. The amount of voids 28 can be suppressed. For this reason, Example 1 does not require a step of evacuating the substrate 10, and the through electrode 18 can be formed with high manufacturing efficiency.

  Further, as shown in FIGS. 7A and 7B, the first cavity 34 is provided to extend in two directions so as to be symmetric with respect to the through electrode 18. When squeegee printing is performed from the two directions where the first cavity 34 is provided and the through hole 26 is filled with solder paste, the amount of voids 28 generated in the through hole 26 can be suppressed. That is, in the first embodiment, squeegee printing can be performed in a reciprocating manner while suppressing the amount of voids 28 generated in the through hole 26. Therefore, as in Conventional Example 3 shown in FIG. 5, compared to the case where the hole 24 is provided only in one direction on the side surface of the through electrode 18, the first example can form the through electrode 18 with high manufacturing efficiency. In addition, the filling property of the solder paste filled in the through holes 26 can be improved.

  Further, as shown in FIGS. 7A and 7B, the first cavity 34 is covered with the resin 16. For this reason, as shown in FIG.10 (c), even if squeegee printing is performed on the resin 16, the 1st cavity part 34 is not filled with a solder paste. That is, it is possible to continue to maintain the function of the air hole in the through hole 26 of the first cavity 34. Therefore, when the hole 24 penetrates the surface of the resin 16 as in Conventional Example 3 shown in FIG. 5, it is necessary to perform squeegee printing using a mask or the like so that the hole 24 is not filled with solder paste. However, since the first embodiment does not need to use a mask or the like, the through electrode 18 can be formed with high manufacturing efficiency. In addition, since the resin 16 has poor solder paste wettability, even if the through hole 26 is filled with the solder paste, the solder paste in the through hole 26 does not leak into the first cavity 34.

  In the method for manufacturing the surface acoustic wave device according to the first embodiment, as illustrated in FIG. 8D, the first opening 38 is provided on the electrode 14, and the fifth opening 45 is provided on the functional portion of the element 12. A first resin film 36 is formed on the substrate 10. As shown in FIG. 9C, the second opening 39 is provided on the first opening 38 on the electrode 14, and the fourth opening 43 is extended in two directions from the side surface of the second opening 39. A second resin film 42 having a sixth opening 47 is formed on the first resin film 36 on the fifth opening 45 on the functional portion of the element 12. As shown in FIG. 10B, the first opening 38, the second opening 39, and the third opening 41 are formed on the electrode 14, and the first resin film 36, the second resin film 42, and the third resin film are formed. A through hole 26 penetrating 46 is formed, the fourth opening 43 is covered and becomes the first cavity 34, and the fifth opening 45 and the sixth opening 47 on the functional part of the element 12 are covered and the first opening 34 is covered. A third resin film 46 having a third opening 41 on the second opening 39 is formed on the second resin film 42 so that the two cavities 22 are formed. As described above, the first resin film 36 having the first opening 38 and the fifth opening 45, the second opening 39, the second resin film 42 having the fourth opening 43 and the sixth opening 47, and the third resin film 36. By forming the resin 16 including the three layers of the third resin film 46 having the opening 41, the through hole 26, the first cavity 34, and the second cavity 22 can be easily formed.

  In the first embodiment, as illustrated in FIG. 7B, the first cavity portion 34 is provided near the bottom surface of the through electrode 18, but is not limited thereto. However, since the through electrode 18 is formed by performing squeegee printing on the resin 16 and filling the through hole 26 with solder paste, the void 28 is likely to be generated on the bottom surface of the through hole 26. For this reason, when the 1st cavity part 34 is provided in the bottom face vicinity of the penetration electrode 18, the effect of suppressing the generation amount of the void 28 becomes larger. That is, it is preferable that the bottom surface of the first cavity portion 34 is provided so that a step difference from the bottom surface of the through electrode 18 is small.

  Moreover, although the case where the 1st cavity part 34 was provided so that it might extend in two directions from the side surface of the penetration electrode 18 was shown, it is not restricted to this. If the first cavity 34 is provided so as to extend in two or more directions from the side surface of the through electrode 18, the direction in which squeegee printing can be performed without generating the void 28 in the through hole 26 is increased, and the degree of freedom of squeegee printing is increased. Can be increased. In particular, since squeegee printing can be performed reciprocally, and the manufacturing efficiency of the through electrode 18 and the filling property of the solder paste into the through hole 26 are improved, at least two first cavities 34 are located with respect to the through electrode 18. Are preferably provided so as to be symmetrical.

  Furthermore, although the case where the resin 16 covering the first cavity 34 is a photosensitive epoxy resin is shown, the present invention is not limited to this. It is preferable that the wettability with the solder paste is poor and the material does not leak into the first cavity 34 when the through hole 26 is filled with the solder paste.

  Furthermore, although the case where the through electrode 18 is a solder paste has been shown, the present invention is not limited thereto, and may be a conductive material mainly composed of any one of Cu, Sn, and Pb. In particular, it is preferable that the conductive material is mainly composed of Sn from the viewpoint of reducing the manufacturing cost.

  Further, as shown in FIGS. 7A and 7B, the case where the through electrode 18 is formed on the electrode 14 provided on the substrate 10 is shown, but the present invention is not limited thereto, and the through electrode 18 is not limited thereto. May be provided on the wiring 32. Even in this case, the through electrode 18 is electrically connected to the element 12 through the wiring 32, and functions as a terminal portion for electrically connecting the element 12 to the outside when the surface acoustic wave device is mounted by flip chip.

  FIG. 11A is a top view of the surface acoustic wave device according to the second embodiment, and FIG. 11B is a cross-sectional view taken along a line AA in FIG. Referring to FIGS. 11A and 11B, the first cavity 34 is provided so as to surround the side surface of the through electrode 18 in a circular shape. That is, the first cavity 34 is provided in all directions on the side surface of the through electrode 18. Other configurations are the same as those of the first embodiment and are shown in FIGS. 7A and 7B, and thus the description thereof is omitted.

  The method for manufacturing the surface acoustic wave device according to Example 2 is the same as that of Example 1 except that the mask used in FIG. 9B is changed, and is shown in FIGS. 8A to 10D. Therefore, the description is omitted.

  According to the second embodiment, the first cavity 34 is provided so as to surround the side surface of the through electrode 18 in a circular shape. For this reason, in the squeegee printing of the solder paste shown in FIG. 10C, the amount of voids 28 generated in the through hole 26 even if the 360 ° squeegee printing is performed and the through hole 26 is filled with the solder paste. Can be suppressed. Therefore, the degree of freedom of squeegee printing is increased as compared with the first embodiment, and the through electrode 18 can be formed with higher manufacturing efficiency.

  Further, since the first cavity portion 34 is provided so as to surround the side surface of the through electrode 18 in a circular shape, the volume of the first cavity portion 34 can be increased as compared with the first embodiment. For this reason, in the filling of the solder paste into the through hole 26 by squeegee printing, the air in the through hole 26 is easily removed by the first cavity portion 34. Therefore, compared to the first embodiment, the amount of voids 28 generated in the through hole 26 can be further suppressed.

  In the second embodiment, the case where the first cavity portion 34 is provided so as to surround the side surface of the through electrode 18 in a circular shape is shown, but the present invention is not limited thereto. For example, even if the first cavity 34 is provided so as to surround the side surface of the through electrode 18 even in a square shape, an ellipse shape, or the like, the same effect as in the case of the circular shape can be obtained.

  FIG. 12A is a top view of the surface acoustic wave device according to the third embodiment, and FIG. 12B is a cross-sectional view taken along the line A-A in FIG. Referring to FIGS. 12A and 12B, the resin 16 is not provided in the dicing region 50, and solder paste is applied to the substrate 10 in the dicing region 50 by squeegee printing for forming the through electrode 18. Is provided. The first cavity portion 34 penetrates from the side surface of the through electrode 18 to the end surface of the resin 16, whereby the first cavity portion 34 is connected to the dicing region 50. The other configuration is the same as that of the second embodiment and is shown in FIGS. 11A and 11B, and thus the description thereof is omitted.

  In the surface acoustic wave device manufacturing method according to the third embodiment, the mask used in FIGS. 8C, 9B, and 10A is changed, and the first resin film in the dicing region 50 around the substrate 10 is changed. 36, the second resin film 42 and the third resin film 46 are prevented from being irradiated with ultraviolet rays (UV light). Others are the same as those of the first embodiment, and are shown in FIGS. 8A to 10D, and thus the description thereof is omitted.

  According to Example 3, as shown in FIGS. 12A and 12B, the first cavity 34 penetrates from the side surface of the through electrode 18 to the end surface of the resin 16. For this reason, as shown in FIG. 13, in filling the solder paste into the through hole 26 by squeegee printing, air in the through hole 26 can escape to the dicing region 50 through the first cavity portion 34. Therefore, compared with Example 2, the air in the through-hole 26 becomes easier to escape, and the amount of voids 28 generated in the through-hole 26 can be further suppressed. As described above, when the first cavity 34 and the dicing region 50 are connected and the air in the through hole 26 is extracted using the dicing region 50, the dicing region 50 is not used and corresponds to the dicing region 50. The surface acoustic wave device can be downsized as compared with the case where the region is provided separately and the air in the through hole 26 is removed. Further, since the first cavity portion 34 penetrates from the side surface of the through electrode 18 to the end surface of the resin 16, even if squeegee printing is performed on the resin 16, the first cavity portion 34 is filled with the solder paste. Absent.

  In the third embodiment, as shown in FIGS. 12A and 12B, the case where the solder paste is provided on the substrate 10 in the dicing region 50 is described as an example, but the present invention is not limited thereto. When the through electrode 18 is formed, squeegee printing is performed so that only the through hole 26 is filled with the solder paste, and the solder paste is not filled on the substrate 10 in the dicing region 50, and the solder is formed on the substrate 10 in the dicing region 50. It may be a case where no paste is provided.

  FIG. 14A is a top view of the surface acoustic wave device according to the fourth embodiment, and FIG. 14B is a cross-sectional view taken along a line AA in FIG. 14A and 14B, the end surface of the resin 16 provided above the first cavity portion 34 is closer to the substrate than the end surface of the resin 16 provided below the first cavity portion 34. 10 is provided on the peripheral side. Other configurations are the same as those of the third embodiment and are shown in FIGS. 12A and 12B, and thus the description thereof is omitted.

  In the method of manufacturing the surface acoustic wave device according to the fourth embodiment, the mask used in FIGS. 8C and 9B is changed, and the first resin film 36 and the second resin film 42 in the dicing region 50 are also irradiated with ultraviolet rays. (UV light) is not irradiated. Others are the same as those of the first embodiment, and are shown in FIGS. 8A to 10D, and thus the description thereof is omitted.

  According to the fourth embodiment, as shown in FIGS. 14A and 14B, the end face of the resin 16 provided above the first cavity 34 is provided below the first cavity 34. It is provided on the peripheral side of the substrate 10 from the end face of the resin 16. That is, the dicing region 50 is in a state in which the resin 16 provided above the first cavity portion 34 becomes wrinkles. Therefore, as shown in FIG. 15, even if squeegee printing is performed on the resin 16, the dicing area 50 is not filled with solder paste. When the dicing area 50 is filled with the solder paste as in the third embodiment, the dicing area 50 may be filled with the solder paste before the through hole 26 is filled with the solder paste. In this case, the air in the through hole 26 cannot be extracted to the dicing region 50 through the first cavity 34. However, in Example 4, since the dicing area 50 is not filled with the solder paste, the air in the through hole 26 can always be extracted to the dicing area 50 through the first cavity 34. Therefore, compared to the third embodiment, the amount of voids 28 generated in the through hole 26 can be further suppressed.

  In the first to fourth embodiments, the surface acoustic wave device having the WLP structure is shown, but the present invention is not limited to this. For other electronic components having a WLP structure, the same effects as those of the surface acoustic wave devices shown in the first to fourth embodiments can be obtained by using the present invention. In particular, an acoustic wave device such as a surface acoustic wave device or a piezoelectric thin film resonator that requires the second cavity 22 to be provided on a functional part of the acoustic wave element provided on the piezoelectric substrate is a functional part of the acoustic wave element. In order to maintain the strength of the resin 16 having the second cavity portion 22 thereon, the thickness of the resin 16 must be sufficiently increased. That is, the depth of the through hole 26 is increased. For this reason, it becomes more difficult to fill the through holes 26 with solder paste by squeegee printing, and voids 28 are likely to be generated, so that the effect of the present invention is further increased.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

FIG. 1 is a cross-sectional view of an electronic component according to Conventional Example 1. FIG. 2 is a cross-sectional view of a surface acoustic wave device according to Conventional Example 2. FIG. 3 is a cross-sectional view of a surface acoustic wave device according to Conventional Example 3. FIG. 4 is a cross-sectional view for explaining the problem of the surface acoustic wave device according to the second conventional example. FIG. 5 is a cross-sectional view for explaining the problem of the surface acoustic wave device according to Conventional Example 3. FIG. 6 is a top view of a wafer for explaining a method of manufacturing a surface acoustic wave device. FIG. 7A is a top view of the surface acoustic wave device according to the first embodiment, and FIG. 7B is a cross-sectional view taken along a line AA in FIG. FIG. 8A to FIG. 8D are cross-sectional views (part 1) illustrating the method for manufacturing the surface acoustic wave device according to the first embodiment. FIG. 9A to FIG. 9D are cross-sectional views (part 2) illustrating the method for manufacturing the surface acoustic wave device according to the first embodiment. 10A to 10D are cross-sectional views (part 3) illustrating the method for manufacturing the surface acoustic wave device according to the first embodiment. FIG. 11A is a top view of the surface acoustic wave device according to the second embodiment, and FIG. 11B is a cross-sectional view taken along a line AA in FIG. FIG. 12A is a top view of the surface acoustic wave device according to the third embodiment, and FIG. 12B is a cross-sectional view taken along the line A-A in FIG. FIG. 13 is a cross-sectional view for explaining the effect of the surface acoustic wave device according to the third embodiment. FIG. 14A is a top view of the surface acoustic wave device according to the fourth embodiment, and FIG. 14B is a cross-sectional view taken along a line AA in FIG. FIG. 15 is a cross-sectional view for explaining the effect of the surface acoustic wave device according to the fourth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Board | substrate 12 Element 14 Electrode 16 Resin 18 Through electrode 20 Solder ball 22 2nd cavity part 24 Hole part 25 Surface acoustic wave device 26 Through hole 28 Void 32 Wiring 34 1st cavity part 36 1st resin film 38 1st opening part 39 2nd opening 40 Protective film 41 3rd opening 42 2nd resin film 43 4th opening 44 Pressing roll 45 5th opening 46 3rd resin film 47 6th opening 48 Squeegee 50 Dicing area

Claims (12)

An element provided on a substrate;
An electrode provided on the substrate and electrically connected to the element;
A resin provided on the substrate so as to cover the element;
A through electrode provided on the electrode and penetrating the resin;
And wherein the resin is to have a first cavity portion provided to extend in two or more directions from the side surface of the through electrode, the upper and lower surfaces of the first cavity portion is covered with the resin Electronic parts.   The electronic component according to claim 1, wherein the first cavity is covered with the resin.   The electronic component according to claim 1, wherein at least two of the first cavities are provided so as to be symmetric with respect to the through electrode.   4. The electronic component according to claim 1, wherein the first cavity is provided so as to surround a side surface of the through electrode. 5.   5. The electronic component according to claim 1, wherein the first cavity portion penetrates from a side surface of the through electrode to an end surface of the resin.   The end face of the resin provided above the first cavity is provided on the peripheral side of the substrate from the end face of the resin provided below the first cavity. Item 5. An electronic component according to Item 5.   The electronic component according to any one of claims 1 to 6, wherein the through electrode is made of a conductive material containing Cu, Sn, or Pb as a main component.   The said board | substrate is a piezoelectric substrate, the said element is an elastic wave element, The said resin has a 2nd cavity part on the functional part of the said acoustic wave element, The any one of Claim 1 to 7 characterized by the above-mentioned. The electronic component described. Forming an element and an electrode electrically connected to the element on a substrate;
Forming a first resin film covering the element on the substrate and having a first opening on the electrode;
A second resin film having a second opening on the first opening and a fourth opening extending in two or more directions from a side surface of the second opening is formed on the first resin film. Process,
The first opening, the second opening, and the third opening are formed so that a through-hole penetrating the first resin film, the second resin film, and the third resin film is formed, and the first opening is formed. Forming the third resin film having the third opening on the second opening on the second resin so that the four openings become the first cavity;
Forming a through electrode on the electrode by filling the through hole with a conductive material. The step of forming the first resin film includes the step of forming the first resin film having a fifth opening on the functional portion of the element,
The step of forming the second resin film includes the step of forming the second resin film having a sixth opening on the fifth opening,
The step of forming the third resin film includes a step of forming the third resin film so that the fifth opening and the sixth opening become a second cavity. The manufacturing method of the electronic component of description.   11. The manufacturing of an electronic component according to claim 9, wherein the step of forming the through electrode is a step of forming the through electrode by filling the through hole with a conductive material by squeegee printing. Method. Forming an element on the substrate and an electrode electrically connected to the element, and forming a resin on the substrate so as to cover the element;
Forming a through hole penetrating the resin on the electrode and a first cavity extending in two or more directions from a side surface of the through hole;
Forming a through electrode on the electrode by filling the through hole with a conductive material by squeegee printing.

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