Elastic wave device and module including elastic wave device

Abstract

To improve the reliability and lifetime of elastic wave device and module in which the electric connection between a device chip and the outside is obtained by a pillar bump.SOLUTION: A device chip 1 includes a functional element 6 on a functional surface 1a thereof, a fused pad 1b for a fusible part 3b of a pillar bump 3, a wire connecting the functional element 6 and the fused pad 1b, and a support layer 5 that surrounds a region where the functional element 6 is formed on the functional surface 1a and is formed of an insulating material for forming an internal space 7 for sealing the functional element 6 by adhering to a package substrate 2 side. The support layer 5 includes a reception hole 5a of the pillar bump 3 to make the fused pad 1b exist at a hole bottom.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an acoustic wave device suitable for use as a frequency filter in a mobile communication device or the like, and to an improvement in a module including the acoustic wave device. [Background technology]

[0002] There are bare-chip acoustic wave devices (electronic devices that apply surface acoustic waves / SAW devices) that are configured to be flip-chip mounted using pillar bumps on an aggregate substrate that will become a package substrate or an aggregate substrate that will become a module substrate, and that are electrically connected to the package substrate or the like using pillar bumps. The cross-sectional structure is shown in FIG. In Figure 19, reference numeral 100 denotes a device chip, reference numeral 101 denotes a functional element including an IDT electrode, reference numeral 102 denotes a pad for external connection in wiring connected to the functional element 101, reference numeral 103 denotes a support layer (wall layer) made of an insulating material formed to surround the functional element 101, reference numeral 104 denotes a cover layer (roof layer) formed on the support layer 103 to form an internal space 105 above the functional element, reference numeral 106 denotes a via that penetrates the support layer 103 and the cover layer 104 and positions the pad 102 at the bottom of the hole, and reference numeral 107 denotes a pillar bump formed in this via 106. The pillar bump 107 has a structure in which a solder 107b is placed on the top of a cylindrical pillar portion 107a, and the two are integrated together.

[0003] The acoustic wave device configured in this manner is integrated with the pad of the mounting counterpart by melting and solidifying the solder 107b while the solder 107b is pressed against the pad.

[0004] However, the process of forming the pillar bumps 107 on the device chip 100 increases the lead time of the acoustic wave device (first problem). Furthermore, during the process of forming the pillar bumps 107 on the device chip 100, thermal stress and processing loads are imposed on the device chip 100, which reduces the reliability and lifespan of the acoustic wave device (second problem). Summary of the Invention [Problem to be solved by the invention]

[0005] The main problem that this invention aims to solve is to prevent the first and second problems from occurring in acoustic wave devices and modules in which pillar bumps are used to electrically connect the device chip that constitutes the acoustic wave device to the outside. [Means for solving the problem]

[0006] In order to achieve the above object, from a first viewpoint, the present invention provides an acoustic wave device in which a package substrate and a device chip are bonded together by pillar bumps provided upright on a mounting surface of the package substrate for the device chip, the pillar bump includes a pillar portion made of a conductive material and a weldable portion made of solder formed on the pillar portion; The device chip has one surface serving as a functional surface facing the mounting surface of the package substrate, and is provided with a functional element including an IDT electrode on this functional surface, weld pads for the weldable portions of the pillar bumps, wiring connecting the functional element and the weld pads, and a support layer made of an insulating material that surrounds the area on the functional surface where the functional element is formed and is in close contact with the package substrate to form an internal space that seals the functional element, The support layer is formed with a receiving hole for the pillar bump, with the pad to be welded positioned at the bottom of the hole.

[0007] In the acoustic wave device according to this first aspect, the package substrate has, on the mounting surface, an insulating layer that is in close contact with the support layer of the device chip, and a non-formed portion of this insulating layer, and the non-formed portion forms an air passage that allows air in the receiving hole to escape to the outside, which is one aspect of the present invention. In addition, in the acoustic wave device according to the first aspect, one aspect of the present invention is that the support layer is formed with an air passage that allows air in the receiving hole to escape to the outside.

[0008] In order to achieve the above object, from a second viewpoint, the present invention provides an acoustic wave device in which a package substrate and a device chip are bonded together by pillar bumps provided on a mounting surface of the package substrate for the device chip, the pillar bump includes a pillar portion made of a conductive material and a weldable portion made of solder formed on the pillar portion; The device chip has one surface serving as a functional surface facing the mounting surface of the package substrate, and is provided with a functional element including an IDT electrode on this functional surface, weld pads for the weldable portions of the pillar bumps, wiring connecting the functional element and the weld pads, a support layer made of an insulating material surrounding an area on the functional surface where the functional element is formed, and a cover layer made of an insulating material formed on the support layer to form an internal space for sealing the functional element, The support layer and the cover layer are formed with holes for receiving the pillar bumps, with the pads to be welded positioned at the bottom of the holes.

[0009] In the acoustic wave device according to the second aspect, one aspect of the present invention is to form an air passage in the support layer and the cover layer, or in the cover layer, that allows air in the receiving hole to escape to the outside.

[0010] In the acoustic wave devices according to the first and second aspects, it is one aspect of the present invention that the pillar bump has a thickness of 10 μm or less.

[0011] In order to achieve the above object, from a third viewpoint, the present invention provides a module including an acoustic wave device, wherein at least one of the mounted electronic devices is a device chip that functions as an acoustic wave device, and the module substrate and the device chip are joined by pillar bumps provided on a mounting surface of the module substrate for the device chip, the pillar bump includes a pillar portion made of a conductive material and a weldable portion made of solder formed on the pillar portion; the device chip has one surface serving as a functional surface facing the mounting surface of the module substrate, and is provided with a functional element including an IDT electrode on this functional surface, weld pads for the weldable portions of the pillar bumps, wiring connecting the functional element and the weld pads, and a support layer made of the insulating material that surrounds an area on the functional surface where the functional element is formed and is in close contact with the module substrate to form an internal space that seals the functional element; The support layer is formed with a receiving hole for the pillar bump, with the pad to be welded positioned at the bottom of the hole.

[0012] In the module including the acoustic wave device according to the third aspect, the module substrate has, on the mounting surface, an insulating layer that is in close contact with the support layer of the device chip, and a portion where the insulating layer is not formed; In one aspect of the present invention, the non-formed portion forms an air passage for venting air from within the receiving hole to the outside. In addition, in a module equipped with an acoustic wave device according to the third aspect, one aspect of the present invention is to form an air passage in the support layer to allow air in the receiving hole to escape to the outside.

[0013] In order to achieve the above object, from a fourth viewpoint, the present invention provides a module including an acoustic wave device, wherein at least one of the mounted electronic devices is a device chip that functions as an acoustic wave device, and the module substrate and the device chip are joined by pillar bumps provided on a mounting surface of the module substrate for the device chip, the pillar bump includes a pillar portion made of a conductive material and a weldable portion made of solder formed on the pillar portion; The device chip has one surface serving as a functional surface facing the mounting surface of the module substrate, and is provided with a functional element including an IDT electrode on this functional surface, weld pads for the weldable portions of the pillar bumps, wiring connecting the functional element and the weld pads, a support layer made of an insulating material surrounding an area on the functional surface where the functional element is formed, and a cover layer made of an insulating material formed on the support layer to form an internal space for sealing the functional element, The support layer and the cover layer are formed with holes for receiving the pillar bumps, with the pads to be welded positioned at the bottom of the holes.

[0014] In a module equipped with an acoustic wave device according to the fourth aspect, one aspect of the present invention is to form an air passage in the support layer and the cover layer, or in the cover layer, that allows air in the receiving hole to escape to the outside.

[0015] In addition, in a module including the acoustic wave device according to the third and fourth aspects, it is one aspect of the present invention that the thickness of the pillar bump is 10 μm or less. [Effects of the Invention]

[0016] In the acoustic wave device according to the present invention, the pillar bumps are provided on the package substrate side, and the receiving holes for the pillar bumps are provided on the device chip side, thereby rationally solving the first and second problems. Furthermore, in the module according to the present invention, the pillar bumps are provided on the module substrate side, and corresponding receiving holes are provided on the device chip side, thereby rationally solving the first and second problems. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a cross-sectional view showing the separation of a device chip and a package substrate that constitute an acoustic wave device (first example) according to one embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of the first example. [Figure 3] FIG. 3 is a cross-sectional view taken along line AA in FIG. [Figure 4] FIG. 4 is a diagram showing an example of a configuration of a resonator formed on a device chip constituting the first example. [Figure 5] FIG. 5 is a configuration diagram showing an example of a circuit formed on the device chip constituting the first example. [Figure 6] FIG. 6 is a cross-sectional view showing the separation of a device chip and a package substrate constituting an acoustic wave device (second example) according to one embodiment of the present invention. [Figure 7] FIG. 7 is a cross-sectional view of the second example taken along line CC in FIG. [Figure 8] FIG. 8 is a cross-sectional view taken along line BB in FIG. [Figure 9] FIG. 9 is a perspective view showing the main part of the device chip constituting the second example. [Figure 10] FIG. 10 is a cross-sectional view showing the separation of a device chip and a package substrate constituting an acoustic wave device (third example) according to one embodiment of the present invention. [Figure 11] FIG. 11 is a cross-sectional view of the third example taken along line EE in FIG. [Figure 12] FIG. 12 is a plan view showing the third example as viewed from the package substrate side. [Figure 13]FIG. 13 is a cross-sectional view taken along line DD in FIG. [Figure 14] FIG. 14 is a perspective view showing the configuration of the main part of the device chip constituting the third example. [Figure 15] FIG. 15 is a perspective view showing the configuration of the main part of the device chip constituting the third example. [Figure 16] FIG. 16 is a cross-sectional view of a module (fourth example) according to an embodiment of the present invention. [Figure 17] FIG. 17 is a cross-sectional view of a module (fifth example) according to an embodiment of the present invention. [Figure 18] FIG. 18 is a cross-sectional view of a module (sixth example) according to an embodiment of the present invention. [Figure 19] FIG. 19 is a cross-sectional view of a conventional acoustic wave device. DETAILED DESCRIPTION OF THE INVENTION

[0018] Exemplary embodiments of the present invention will now be described with reference to Figures 1 to 18. An acoustic wave device D and a module M according to the embodiments are suitable for use as a frequency filter in a mobile communication device or the like.

[0019] (Example 1) 1 to 5 show a first example of an acoustic wave device D. FIG. The acoustic wave device D according to the first example is composed of a device chip 1 and a package substrate 2. The package substrate 2 and the device chip 1 are joined by pillar bumps 3 provided upright on the mounting surface 2 a of the package substrate 2 for the device chip 1 .

[0020] The package substrate 2 has pads 2b on the mounting surface 2a, which become part of the wiring on the package substrate 2 side. The pillar bump 3 includes a pillar portion 3a made of a conductive material and a weldable portion 3b made of solder and formed on the pillar portion 3a. The thickness of the pillar bump 3 is preferably 10 μm or less. One end of the pillar portion 3a is fixed to the pad 2b, and the other end of the pillar portion 3a is provided with the weldable portion 3b. The pillar portion 3a has a columnar shape formed so that the central axis is perpendicular to the mounting surface 2a. Typically, the pillar portion 3a has a cylindrical shape. The weldable portion 3b is typically integrated with the pillar portion 3a by applying solder to the other end of the pillar portion 3a by printing and then performing a reflow process. The pillar portions 3a of the package substrate 2 are formed on the package substrate 2 as described above so as to correspond to the positions where the pads 1b to be welded, which will be described later, are formed on the device chip 1. The mounting surface 2a of the package substrate 2 is covered with a solder resist layer serving as an insulating layer 4. This solder resist layer adheres closely to the support layer 5 of the device chip 1 to form an internal space 7 that seals a functional element 6, which will be described later. Furthermore, on the mounting surface 2a of the package substrate 2, blank areas 4a where the solder resist layer is not formed are provided, and these non-forming areas 4a form ventilation paths 8, which will be described later.

[0021] The device chip 1 has one surface serving as a functional surface 1a facing the mounting surface 2a of the package substrate 2, and is equipped with a functional element 6 including an IDT electrode 6b on this functional surface 1a, a weldable pad 1b for the weldable portion 3b of the pillar bump 3, wiring (not shown) connecting the functional element 6 and the weldable pad 1b, and a support layer 5 made of an insulating material that surrounds the area on the functional surface 1a where the functional element 6 is formed and is adhered to the package substrate 2 to form an internal space 7 that seals the functional element 6.

[0022] The functional element 6, wiring, and weld pad 1b are made of a conductive material, typically a metal film. These are provided on a wafer that will become the device chip 1, and are formed into a predetermined pattern for each region that will become the device chip 1 using photoresist technology and etching.

[0023] The support layer 5 is made of an insulating material such as an insulating resin. The thickness of the support layer 5 on the functional surface 1a is made thicker than the thickness of the functional elements 6 and the wiring. The support layer 5 is also formed so as to surround the formation area of ​​the functional elements 6. The support layer 5 is formed as described above by forming the resin layer on one surface of the wafer for each area that will become the device chip 1 on the wafer, and then using photoresist technology and etching.

[0024] The support layer 5 is formed with receiving holes 5a for the pillar bumps 3, with the pads 1b to be welded positioned at the bottom of the holes. In the illustrated example, a weld pad 1b is formed at each of the four corners of the device chip 1, and correspondingly, a bottomed receiving hole 5a is formed in the upper surface of the support layer 5 between the inner surface 5b facing the internal space 7 and the outer surface 5c opposite it, with an opening in the upper surface of the support layer 5 and leading to the weld pad 1b.

[0025] The device chip 1 configured in this manner is integrated with the package substrate 2 by melting and solidifying the weldable portions 3b to be integrated with the weld pads 1b with the corresponding pillar bumps 3 of the package substrate 2 inserted into the receiving holes 5a. The upper surface 5d of the support layer 5 is in close contact with the insulating layer 4 of the package substrate 2, thereby providing the acoustic wave device D with the internal space 7.

[0026] In the first example, the package substrate 2 has, on the mounting surface 2a, an insulating layer 4 that is in close contact with the support layer 5 of the device chip 1, and a non-forming portion 4a of this insulating layer 4. The non-forming portion 4a forms an air passage 8 that allows air in the receiving hole 5a to escape to the outside. In the illustrated example, the non-forming portion 4a is an elliptical blank of the insulating layer 4 when the acoustic wave device D is viewed in a direction perpendicular to the mounting surface 2a (see FIG. 3). The non-forming portion 4a is located on the upper surface 5d of the support layer 5 and is formed to have a portion 4b that communicates with the receiving hole 5a and a portion 4c that is located outward from the outer surface 5c of the support layer 5. As a result, in this first example, when the package substrate 2 having the pillar bumps 3 and the device chip 1 having the receiving holes 5a are mounted and integrated as described above, the air inside the receiving holes 5a is released to the outside, allowing the pillar bumps 3 to be smoothly introduced into the receiving holes 5a. Typically, such mounting is performed for each region that becomes each package substrate 2 in the aggregate substrate that becomes the package substrate 2, and the non-formed portions 4a that become the air passages 8 are also formed in each of these regions.

[0027] The shape of the non-formation areas 4a for forming the air passages 8 is merely an example, and the pattern of the non-formation areas 4a may be adjusted as needed.

[0028] In the first example, the insulating layer 4 of the package substrate 2 is butted against the support layer 5 of the device chip 1 with a predetermined pressing force so that the two are in close contact with each other, but this pressing force can be absorbed by the weldable portion 3b of the pillar bump 3. The receiving holes 5a serve as dams for the weldable portions 3b of the pillar bumps 3. The height of the internal space 7, i.e., the distance between the functional surface 1a of the device chip 1 and the insulating layer 4 of the package substrate 2, is controlled by the thickness of the support layer 5.

[0029] Typically, the device chip 13 is configured to have a rectangular plate shape with a side of 0.5 to 1 mm and a thickness of 0.15 to 0.2 mm, and the support layer 5 has a thickness of 20 to 30 μm. The pillar bumps 3 have a height of 50 to 80 μm. The acoustic wave device D constructed from these bumps has a thickness of about 0.25 to 0.3 mm.

[0030] The device chip 13 has a function of propagating elastic waves. A piezoelectric material such as lithium tantalate or lithium niobate is typically used for the device chip 13. The device chip 13 may also be configured by laminating these piezoelectric materials on a support such as sapphire, silicon, alumina, spinel, quartz, or glass.

[0031] Figure 4 shows an example of a resonator 6a serving as a SAW filter. The resonator 6a has an IDT electrode 6b and a reflector 6c formed on either side of the IDT electrode 6b. The IDT electrode 6b consists of an electrode pair, and each electrode pair has multiple electrode fingers 6d arranged in parallel so that their length direction intersects the propagation direction x of the acoustic wave, and each electrode pair is connected by a busbar 6e at one end of the electrode fingers. The reflector 6c has multiple electrode fingers 6f arranged in parallel so that their length direction intersects the propagation direction x of the acoustic wave, and each electrode finger 6d is connected by a busbar 7g at the ends thereof. In the illustrated example, a plurality of such resonators 7 a are formed on one device chip 13 .

[0032] Figure 5 shows the concept of an example of a circuit 9 provided on one device chip 1. Reference numeral 6aa denotes a resonator 6a connected in series between input / output ports 9, reference numeral 6ab denotes a resonator 6a connected in parallel between input / output ports 10, and reference numeral 11 denotes a ground. The number and arrangement of the resonators 6a can be changed as needed. In other words, a ladder-type filter is configured by the circuit 9 of Figure 5.

[0033] (Example 2) 6 to 9 show a second example of the acoustic wave device D. FIG. In the acoustic wave device D according to the second example, an air passage 8 for releasing the air in the receiving hole 5a to the outside is formed in the support layer 5. In the second example, the air passage 8 is not formed on the package substrate 2 side. The remaining configuration of this second example is substantially the same as that of the first example, so the reference numerals used in the drawings showing the first example are used in the drawings showing the second example, and the description thereof will be omitted.

[0034] In the second example, the mounting surface 2a of the package substrate 2 is covered with an insulating layer 4 except for the positions where the pillar bumps 3 are provided.

[0035] Each receiving hole 5a in the support layer 5 is formed so that the cross section of the hole follows the outline of an imaginary quadrangle S having a side Sa parallel to one side 1d of the device chip 1, which has a rectangular shape when viewed in a direction perpendicular to the functional surface 1a, and a side Sb parallel to the other side 1e adjacent to the side 1d across a corner 1c (see Figure 8). In addition, the support layer 5 has a notch 5e formed in communication with the receiving hole 5a at the outer corner Sd side opposite to the inner corner Sc side facing the internal space 7 of the imaginary rectangle. The cutout portion 5e is formed in a range extending from the upper surface 5d of the support layer 5 to the functional surface 1a of the device chip 1 in a direction perpendicular to the functional surface 1a of the device chip 1, and in a direction parallel to the functional surface 1a of the device chip 1, it is formed in a range extending from the receiving hole 5a to the corner 1c of the device chip 1. As a result, even in this second example, when the package substrate 2 having the pillar bump 3 and the device chip 1 having the receiving hole 5a are integrated as described above, the air inside the receiving hole 5a can be released to the outside, allowing the pillar bump 3 to be smoothly introduced into the receiving hole 5a. That is, in this second example, the notch 5e functions as the ventilation portion 8. The cutout portion 5e can typically be formed by forming a support layer 5 in each area of ​​the wafer that will become the device chip 1, and then using photoresist technology and etching.

[0036] The shape of the cutouts 5e for forming the ventilation paths 8 is merely an example. The pattern of the cutouts 5e may be adjusted as needed.

[0037] (Example 3) 10 to 15 show a third example of the acoustic wave device D. FIG. The acoustic wave device D according to the third example includes a cover layer 12 formed on the support layer 5 and made of an insulating material to form an internal space 7 that seals the functional element 6. Then, the support layer 5 and the cover layer 12 are formed with receiving holes 5a for the pillar bumps 3, with the pads 1b to be welded positioned at the bottom of the holes. Additionally, in the acoustic wave device D according to the third example, an air passage 8 is formed on the support layer 5 and the cover layer 12 side, allowing air in the receiving hole 5a to escape to the outside. In the third example, the air passage 8 is not formed on the package substrate 2 side. Typically, the cover layer 12 is 20 to 30 μm thick. The remaining configuration of this third example is substantially the same as that of the first example, so the reference numerals used in the drawings showing the first example are used in the drawings showing the third example, and the description thereof will be omitted.

[0038] The cover layer 12 is made of an insulating material such as an insulating resin. One surface of the cover layer 12 is fixed to the upper surface 5d of the support layer 5, and the cover layer 12 is supported by the support layer 5, so as to form an internal space 7 between the support layer 5 and the cover layer 12, which seals the functional element 6. The cover layer 12 is typically formed by placing a film constituting the cover layer 12 on the wafer on which the support layer 5 is formed, and then fixing the film to the support layer 5.

[0039] In the third example, the mounting surface 2a of the package substrate 2 is covered with an insulating layer 4 except for the positions where the pillar bumps 3 are provided.

[0040] The receiving holes 5a formed in the support layer 5 and the cover layer 12 are each formed so that the cross section of the hole follows the outline of an imaginary rectangle S having a side Sa parallel to one side 1d of the device chip 1, which has a rectangular shape when viewed in a direction perpendicular to the functional surface 1a, and a side Sb parallel to the other side 1e adjacent to the side 1d across a corner 1c (see Figure 13). In addition, the support layer 5 and the cover layer 12 have a cutout portion 5e formed on the outer corner Sd side of the imaginary rectangle S, which is opposite to the inner corner Sc side facing the internal space 7, and which communicates with the receiving hole 5a. The cutout portion 5e is formed in a range extending from the upper surface 12a of the cover layer 12 to the functional surface 1a of the device chip 1 in a direction perpendicular to the functional surface 1a of the device chip 1, and is formed in a range extending from the receiving hole 5a to the corner 1c of the device chip 1 in a direction parallel to the functional surface 1a of the device chip 1. As a result, even in this third example, when the package substrate 2 having the pillar bump 3 and the device chip 1 having the receiving hole 5a are integrated as described above, the air inside the receiving hole 5a can be released to the outside, allowing the pillar bump 3 to be smoothly introduced into the receiving hole 5a. That is, in this third example, the notch 5e functions as the ventilation portion 8.

[0041] The cutout portion 5e can typically be formed by forming a support layer 5 and a cover layer 12 in each area of ​​the wafer that will become the device chip 1, and then using photoresist technology and etching.

[0042] 15 shows an example in which the same cutout portion 5e as above is formed only in the cover layer 12. In this example, the cutout portion 5e is also formed in a range from the upper surface 12a of the cover layer 12 to the upper surface 5d of the support layer 5 in a direction perpendicular to the functional surface 1a of the device chip 1, and is formed in a range from the receiving hole 5a to the corner 1c of the device chip 1 in a direction parallel to the functional surface 1a of the device chip 1.

[0043] The shape of the cutouts 5e for forming the ventilation paths 8 is merely an example. The pattern of the cutouts 5e may be adjusted as needed.

[0044] (Example 4) FIG. 16 shows a module M including an acoustic wave device D as a fourth example. The module M of the fourth example has at least one mounted electronic device as a device chip 1 that functions as an acoustic wave device D, and the module substrate 13 and the device chip 1 are joined by pillar bumps 3 that are erected on the mounting surface 2a of the device chip 1 on the module substrate 13. The pillar bump 3 includes a pillar portion 3a made of a conductive material and a weldable portion 3b made of solder and formed on the pillar portion 3a. The device chip 1 has one surface serving as a functional surface 1a facing the mounting surface 2a of the module substrate 13, and is equipped with a functional element 6 including an IDT electrode on this functional surface 1a, weldable pads 1b for the weldable portions 3b of the pillar bumps 3, wiring connecting the functional element 6 and the weldable pads 1b, and a support layer 5 made of the insulating material that surrounds the area on the functional surface 1a where the functional element 6 is formed and is adhered to the module substrate 13 side to form an internal space 7 that seals the functional element 6. The support layer 5 is formed with receiving holes 5a for the pillar bumps 3, with the pads 1b to be welded positioned at the bottom of the holes.

[0045] In addition, the module substrate 13 has, on the mounting surface 2a, an insulating layer 4 that is in close contact with the support layer 5 of the device chip 1, and a non-formed portion 4a of this insulating layer 4, and the non-formed portion 4a forms an air passage 8 that allows air in the receiving hole 5a to escape to the outside.

[0046] In this fourth example, a module substrate 13 has a configuration equivalent to the package substrate 2 in the first example, and multiple acoustic wave devices D may be mounted on the mounting surface 2a of the module substrate 13, or an electronic device other than the acoustic wave device D (not shown) may be mounted on the mounting surface 2a. Typical examples of electronic devices other than the acoustic wave device D include power amplifiers, low-noise amplifiers, semiconductor devices that function as switches, and passive components that function as resistors, capacitors, coils, and the like.

[0047] The remaining configuration of this fourth example is substantially the same as that of the first example, so the reference numerals used in the drawings showing the first example are used in the drawings showing the fourth example, and the description thereof will be omitted.

[0048] (Example 5) FIG. 17 shows a module M including an acoustic wave device D as a fifth example. The module M of the fifth example has at least one mounted electronic device as a device chip 1 that functions as an acoustic wave device D, and the module substrate 13 and the device chip 1 are joined by pillar bumps 3 that are erected on the mounting surface 2a of the device chip 1 on the module substrate 13. The pillar bump 3 includes a pillar portion 3a made of a conductive material and a weldable portion 3b made of solder and formed on the pillar portion 3a. The device chip 1 has one surface serving as a functional surface 1a facing the mounting surface 2a of the module substrate 13, and is equipped with a functional element 6 including an IDT electrode on this functional surface 1a, weldable pads 1b for the weldable portions 3b of the pillar bumps 3, wiring connecting the functional element 6 and the weldable pads 1b, and a support layer 5 made of the insulating material that surrounds the area on the functional surface 1a where the functional element 6 is formed and is adhered to the module substrate 13 side to form an internal space 7 that seals the functional element 6. Then, the support layer 5 is formed with receiving holes 5a for the pillar bumps 3, with the pads 1b to be welded positioned at the bottom of the holes.

[0049] In this fifth example, a module substrate 13 has a configuration equivalent to the package substrate 2 in the second example, and multiple acoustic wave devices D may be mounted on the mounting surface 2a of the module substrate 13, or an electronic device other than the acoustic wave device D (not shown) may be mounted on the mounting surface 2a.

[0050] Furthermore, the support layer 5 is formed with an air passage 8 for releasing the air in the receiving hole 5a to the outside. In the fifth example, the ventilation path 8 is not formed on the module substrate 13 side. In the fifth example, the mounting surface 2a of the module substrate 13 is covered with an insulating layer 4 except for the positions where the pillar bumps 3 are provided.

[0051] The remaining configuration of the fifth example is substantially the same as that of the second example, so the reference numerals used in the drawings showing the second example are used in the drawings showing the fourth example, and the description thereof will be omitted.

[0052] (Example 6) FIG. 18 shows a module M including an acoustic wave device D as a sixth example. A module M according to a sixth example is a module M in which at least one of the mounted electronic devices is a device chip 1 that functions as an acoustic wave device D, and a module substrate 13 and the device chip 1 are joined by pillar bumps 3 that are provided on a mounting surface 2 a of the device chip 1 on the module substrate 13, The pillar bump 3 includes a pillar portion 3a made of a conductive material and a weldable portion 3b made of solder and formed on the pillar portion 3a. The device chip 1 has one surface serving as a functional surface 1a facing the mounting surface 2a of the module substrate 13, and is provided with a functional element 6 including an IDT electrode on this functional surface 1a, a weldable pad 1b for the weldable portion 3b of the pillar bump 3, wiring connecting the functional element 6 and the weldable pad 1b, a support layer 5 made of an insulating material surrounding the area on the functional surface 1a where the functional element 6 is formed, and a cover layer 12 made of an insulating material formed on the support layer 5 to form an internal space 7 that seals the functional element 6. Then, the support layer 5 and the cover layer 12 are formed with receiving holes 5a for the pillar bumps 3, with the pads 1b to be welded positioned at the bottom of the holes.

[0053] In this sixth example, the module substrate 13 has a configuration equivalent to the package substrate 2 in the third example, and multiple acoustic wave devices D may be mounted on the mounting surface 2a of the module substrate 13, or an electronic device other than the acoustic wave device D (not shown) may be mounted on the mounting surface 2a.

[0054] Furthermore, the support layer 5 and the cover layer 12 are formed with ventilation paths 8 for releasing the air in the receiving holes 5a to the outside. As shown in Figure 15, in this sixth example as well, the ventilation paths 8 may be provided only in the cover layer 12. In the sixth example, the ventilation path 8 is not formed on the module substrate 13 side. In the sixth example, the mounting surface 2a of the module substrate 13 is covered with an insulating layer 4 except for the positions where the pillar bumps 3 are provided.

[0055] The remaining configuration of the sixth example is substantially the same as that of the third example, so the reference numerals used in the drawings showing the third example are used in the drawings showing the sixth example, and the description thereof will be omitted. [Explanation of symbols]

[0056] D Acoustic Wave Device M Module 1. Device chip 1a Functionality 1b Pad to be welded 1c Corner 1d, 1e sides 2 Package substrate 2a Mounting surface 2b pad 3 Pillar Bump 3a Pillar section 3b Weldable area 4. Insulation layer 4a Non-formed area 4b, 4c parts 5 Support layer 5a Receptor hole 5b Inside surface 5c External surface 5d top 5e Cutout 6 Functional elements 6a resonator 6b IDT electrode 6c reflector 6d electrode finger 6e Busbar 6f electrode finger 6g busbar 7. Interior Space 8 Ventilation Channel 9 circuits 10 input / output ports 11 Grand 12 Cover Layer 12a Top side 13 Module board x Propagation direction S Virtual rectangle Sa, Sb sides Sc inner corner Sd outer corner

Claims

1. An acoustic wave device in which a package substrate and a device chip are bonded together by pillar bumps provided upright on a mounting surface of the package substrate for the device chip, the pillar bump includes a pillar portion made of a conductive material and a weldable portion made of solder formed on the pillar portion; The device chip has one surface serving as a functional surface facing the mounting surface of the package substrate, and is provided with a functional element including an IDT electrode on this functional surface, weld pads for the weldable portions of the pillar bumps, wiring connecting the functional element and the weld pads, and a support layer made of an insulating material that surrounds an area on the functional surface where the functional element is formed and is in close contact with the package substrate to form an internal space that seals the functional element, An acoustic wave device, wherein the support layer has holes formed therein for receiving the pillar bumps, with the pads to be welded positioned at the bottom of the holes.

2. the package substrate has, on the mounting surface, an insulating layer that is in close contact with the support layer of the device chip, and a portion where the insulating layer is not formed; The acoustic wave device according to claim 1 , wherein the non-formed portion forms an air passage for allowing air in the receiving hole to escape to the outside.

3. The acoustic wave device according to claim 1 , wherein the support layer has an air passage formed therein for allowing air in the receiving hole to escape to the outside.

4. An acoustic wave device in which a package substrate and a device chip are bonded together by pillar bumps provided upright on a mounting surface of the package substrate for the device chip, the pillar bump includes a pillar portion made of a conductive material and a weldable portion made of solder formed on the pillar portion; The device chip has one surface serving as a functional surface facing the mounting surface of the package substrate, and is provided with a functional element including an IDT electrode on this functional surface, weld pads for the weldable portions of the pillar bumps, wiring connecting the functional element and the weld pads, a support layer made of an insulating material surrounding an area on the functional surface where the functional element is formed, and a cover layer made of an insulating material formed on the support layer to form an internal space that seals the functional element, An acoustic wave device, wherein the support layer and the cover layer are formed with holes for receiving the pillar bumps, with the pads to be welded positioned at the bottom of the holes.

5. The acoustic wave device according to claim 4 , wherein an air passage for releasing air from the receiving hole to the outside is formed in the support layer and the cover layer, or in the cover layer.

6. 6. The acoustic wave device according to claim 1, wherein the pillar bump has a thickness of 10 [mu]m or less.

7. A module in which at least one of the mounted electronic devices is a device chip that functions as an acoustic wave device, and a module substrate and the device chip are joined by pillar bumps provided on a mounting surface of the module substrate for the device chip, the pillar bump includes a pillar portion made of a conductive material and a weldable portion made of solder formed on the pillar portion; the device chip has one surface serving as a functional surface facing the mounting surface of the module substrate, and is provided with a functional element including an IDT electrode on this functional surface, weld pads for the weldable portions of the pillar bumps, wiring connecting the functional element and the weld pads, and a support layer made of the insulating material that surrounds an area on the functional surface where the functional element is formed and is in close contact with the module substrate to form an internal space that seals the functional element; A module including an acoustic wave device, wherein the support layer has holes formed therein for receiving the pillar bumps, with the pads to be welded positioned at the bottom of the holes.

8. the module substrate has, on the mounting surface, an insulating layer that is in close contact with the support layer of the device chip, and a portion where the insulating layer is not formed; The module equipped with the acoustic wave device according to claim 7 , wherein the non-formed portion forms an air passage for allowing air in the receiving hole to escape to the outside.

9. The module provided with the acoustic wave device according to claim 7 , wherein the support layer has an air passage formed therein for allowing air in the receiving hole to escape to the outside.

10. A module in which at least one of the mounted electronic devices is a device chip that functions as an acoustic wave device, and a module substrate and the device chip are joined by pillar bumps provided on a mounting surface of the module substrate for the device chip, the pillar bump includes a pillar portion made of a conductive material and a weldable portion made of solder formed on the pillar portion; The device chip has one surface serving as a functional surface facing the mounting surface of the module substrate, and is provided with a functional element including an IDT electrode on this functional surface, weld pads for the weldable portions of the pillar bumps, wiring connecting the functional element and the weld pads, a support layer made of an insulating material surrounding an area on the functional surface where the functional element is formed, and a cover layer made of an insulating material formed on the support layer to form an internal space that seals the functional element, A module including an acoustic wave device, wherein the support layer and the cover layer are formed with holes for receiving the pillar bumps, with the pads to be welded positioned at the bottom of the holes.

11. The module provided with the acoustic wave device according to claim 10 , wherein an air passage for allowing air in the receiving hole to escape to the outside is formed in the support layer and the cover layer, or in the cover layer.

12. 12. A module comprising the acoustic wave device according to claim 7, wherein the pillar bumps have a thickness of 10 [mu]m or less.

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