TWI847124B - Wave device - Google Patents

Abstract

A wave device is provided, which includes a substrate with a top surface and a bottom surface, and a plurality of pads arranged on the periphery of the top surface; at least a electronic component is arranged on the top surface of the electronic device, so the plurality of pads on the periphery of the top surface surrounds the electronic component; a cover structure is arranged over above the substrate with the electronic device thereon, and the cover structure and the substrate forms a closed cavity, so the electronic component is arranged in the closed cavity; a first protection layer is covered on the portion surface of the substrate and on the portion surface of the plurality of pads; a conductive layer is arranged on the portion of first protection layer, the plurality of pads, the outer surface of the cover structure, and the portion top surface of the cover structure; and a plurality of bumps is arranged on the conductive layer which is located on the top surface of the cover structure.

Description

Acoustic components

The present invention relates to a semiconductor technology field, and in particular to an acoustic wave element that can improve frequency response performance.

Surface acoustic wave (SAW) elements can excite acoustic waves by applying power to the comb electrodes of an interdigital transducer (IDT) formed on a substrate. Surface acoustic wave elements are widely used in various circuits that process radio signals within a bandwidth of, for example, 45 MHz to 2 GHz. Examples of these circuits are bandpass filters for transmission, bandpass filters for reception, local end oscillator filters, antenna duplexers, intermediate frequency filters, and frequency modulation modulators (FM).

Surface acoustic wave elements require cavities located above functional components of the acoustic wave element composed of comb electrodes, such as electrode fingers of an interdigital transducer, to ensure the performance of the surface acoustic wave element. Conventional surface acoustic wave devices use a ceramic joint having a groove in which the surface acoustic wave element is mounted to form an electrical connection between the surface acoustic wave element and the internal wiring provided on the ceramic package.

However, the use of wires in the wire bonding process will hinder the reduction of the size of the surface acoustic wave device. In order to reduce the size of the surface acoustic wave device, flip-chip bonding was further developed. Since flip-chip bonding does not use wires for mounting, it has achieved a reduction in the size of the surface acoustic wave device.

In recent years, there have been more stringent requirements for reducing the size of surface acoustic wave devices. In some cases, even flip-chip bonding cannot achieve the required size reduction. Therefore, it is proposed to set the surface acoustic wave element on a substrate, and a covering layer is set on the surface of the substrate to define a cavity above the functional components of the surface acoustic wave element, and the above-mentioned covering layer serves as a package. This type of packaging is called wafer level package (WLP), and this packaging method realizes the miniaturization of the surface acoustic wave element.

The main purpose of the present invention is to provide an acoustic wave component, in which a conductive layer is formed on the solder pad to increase the strength between the bump and the solder pad, so as to solve the problem that when the acoustic wave component is packaged in a flip-chip manner, the bump will break due to stress and the solder pad will be pulled off the substrate, causing damage to the entire packaging structure.

Another purpose of the present invention is to provide an acoustic wave element to increase design feasibility, add power bumps or ground bumps, and improve electrical performance.

According to the above purpose, the present invention discloses an acoustic wave element, comprising: a substrate having an upper surface and a lower surface, and a plurality of solder pads are arranged on the periphery of the upper surface; at least one electronic component is arranged on the upper surface of the substrate, so that the plurality of solder pads on the periphery of the upper surface of the substrate surround the electronic component; a cover structure is arranged above the substrate having the electronic component, and the space between the cover structure and the substrate is defined as a closed cavity, so that the electronic component is arranged in the closed cavity. The first protective layer covers part of the upper surface of the substrate and part of the surface of the plurality of solder pads, and exposes part of the surface of the plurality of solder pads not covered by the first protective layer; the conductive layer is disposed on part of the surface of the first protective layer, part of the surface of the plurality of solder pads not covered by the first protective layer, the outer surface of the cover structure and part of the upper surface of the cover structure; and a plurality of bumps are disposed on the conductive layer located on the upper surface of the cover structure.

In a preferred embodiment of the present invention, the cover structure includes, from the substrate upward, a portion of the second protective layer covering a portion of the surface of multiple solder pads adjacent to the electronic components and disposed on the upper surface of the substrate adjacent to the electronic components; a first insulating layer disposed on a portion of the surface of the second protective layer, and the second protective layer and the first insulating layer do not cover the electronic components on the substrate; and a second insulating layer covering a portion of the surface of the first insulating layer, so that the structure formed by the second protective layer and the first insulating layer is defined as the side wall of the cover structure and the second insulating layer is the top wall of the cover structure.

In a preferred embodiment of the present invention, the cover structure includes, from the substrate upward, a portion of the second protective layer covering a portion of the surface of the plurality of solder pads adjacent to the electronic component and a portion of the second protective layer disposed on the upper surface of the substrate adjacent to the electronic component; a first insulating layer disposed on a portion of the surface of the second protective layer and covering a portion of the surface of the plurality of solder pads to expose the unbonded portions of the first insulating layer; Partial surfaces of multiple solder pads covered by the first insulating layer, and the electronic components on the substrate not covered by the second protective layer and the first insulating layer; and the second insulating layer covering a partial surface of the first insulating layer, so that the structure formed by the second protective layer and the first insulating layer is defined as the side wall of the cover structure and the second insulating layer is the top wall of the cover structure.

According to the above purpose, the present invention also discloses another acoustic wave element, comprising: a substrate having an upper surface and a lower surface, and a plurality of solder pads are arranged on the periphery of the upper surface; at least one electronic element is arranged on the upper surface of the substrate, so that the plurality of solder pads on the periphery of the upper surface of the substrate surround the electronic element; a cover structure is arranged above the substrate having the electronic element, and the space between the cover structure and the substrate is defined as a closed cavity, so that the electronic element is arranged in the closed cavity; a first protective layer covers the substrate The first insulating layer is disposed on a portion of the surface of the first protective layer and covers a portion of the surface of the plurality of solder pads to expose a portion of the surface of the plurality of solder pads not covered by the first protective layer; the conductive layer covers a portion of the surface of the first insulating layer, a portion of the surface of the plurality of solder pads not covered by the first protective layer, the outer surface of the cover structure and a portion of the upper surface of the cover structure; and a plurality of bumps are disposed on the conductive layer located on the upper surface of the cover structure.

In a preferred embodiment of the present invention, the second insulating layer and the first insulating layer of the cover structure are in a stepped structure.

In a preferred embodiment of the present invention, the height of the first insulating layer disposed on a portion of the surface of the first protective layer and covering a portion of the surface of multiple pads is the same as the height of the first insulating layer of the cover structure.

In a preferred embodiment of the present invention, the conductor layer is composed of an under ball metallurgy (UBM) and a redistribution layer (RDL), wherein the redistribution layer is disposed on the under ball metallurgy.

In a preferred embodiment of the present invention, the electronic component may be a filter, an oscillator or a sensor.

In a preferred embodiment of the present invention, the bump can be a copper pillar bump, a copper pillar or a C4 bump.

1, 2, 3: Acoustic wave components

10: Substrate

102: Upper surface

104: Lower surface

106: Welding pad

20: Electronic components

30a, 30b, 30c: Cover structure

302a, 302b, 302c: Second protection layer

304a, 304b, 304c: first insulating layer

306a, 306b, 306c: Second insulating layer

32a, 32b, 32c: Closed cavity

34a, 34b, 34c: Outer surface

36a, 36b, 36c: upper surface

40: First protective layer

50a, 50b, 50c: Conductor layer

502a, 502b, 502c: metal layer under the bump

504a, 504b, 504c: Rewiring layer

60: Bump

FIG1 is a cross-sectional schematic diagram showing an embodiment of an acoustic wave element according to the technology disclosed in the present invention.

FIG2 is a cross-sectional schematic diagram showing another embodiment of an acoustic wave element according to the technology disclosed in the present invention.

FIG3 is a cross-sectional schematic diagram showing another embodiment of an acoustic wave element according to the technology disclosed in the present invention.

First, please refer to FIG. 1 . FIG. 1 is a cross-sectional schematic diagram showing an embodiment of an acoustic wave element according to the technology disclosed in the present invention. In FIG. 1 , the acoustic wave element 1 is composed of a substrate 10, an electronic element 20, a cover structure 30a, a first protective layer 40, a conductive layer 50a, and a plurality of bumps 60. The substrate 10 has an upper surface 102 and a lower surface 104, and a plurality of solder pads 106 are provided around the upper surface 102. In one embodiment, the substrate 10 is made of a piezoelectric material, such as quartz, lithium tantalum (LT, LiTaO ₃ ), lead titanate (PTO, PbTiO ₃ ) or lead zirconate titanate (PZT, Pb(Zr,Ti)O ₃ ). The solder pad 106 can be an aluminum pad. The electronic component 20 is disposed on the upper surface 102 of the substrate 10, such that a plurality of pads 106 surrounding the upper surface 102 of the substrate 10 surround the electronic component 20. In the embodiment of the present invention, the electronic component 20 may be a filter, an oscillator or a sensor.

Please continue to refer to Figure 1. A cover structure 30a is provided above the substrate 10 having the electronic component 20. The space between the cover structure 30a and the substrate 10 can be defined as a closed cavity 32a, so the electronic component 20 on the upper surface 102 of the substrate 10 is disposed in the closed cavity 32a. The cover structure 30a can prevent moisture in the external environment from entering the closed cavity 32a, thereby increasing the service life of the electronic component 20 and the reliability of the entire acoustic wave element 1 through the cover structure 30a.

In one embodiment of the present invention, the cover structure 30a includes, from the substrate 10 upward, a second protective layer 302a, a first insulating layer 304a, and a second insulating layer 306a, wherein the second protective layer 302a covers a portion of the surface of the plurality of pads 106 adjacent to the electronic element 20, and the second protective layer 302a is disposed on a portion of the upper surface 102 of the substrate 10 adjacent to the electronic element 20. The first insulating layer 304a is disposed on a portion of the surface of the second protective layer 302a, and the second protective layer 302a and the first insulating layer 304a above the substrate 10 do not cover the electronic element 20 on the substrate 10. The second insulating layer 306a covers part of the surface of the first insulating layer 304a, so that the structure formed by the second protective layer 302a and the first insulating layer 304a can be defined as the side wall of the cover structure 30a and the second insulating layer 306a is the top wall of the cover structure 30a. In one embodiment, the second insulating layer 306a and the first insulating layer 304a in the cover structure 30a are in a stepped structure.

Please continue to refer to FIG. 1 . The acoustic wave device 1 further includes a first protective layer 40, which covers a portion of the upper surface 102 of the substrate 10 and a portion of the surface of the plurality of solder pads 106, and exposes other portions of the surface of the plurality of solder pads 106, that is, the portions of the surface of the plurality of solder pads 106 not covered by the first protective layer 40. It should be noted that the first protective layer 40 covering a portion of the upper surface 102 of the substrate 10 and covering a portion of the surface of the plurality of solder pads 106, and exposing other portions of the surface of the plurality of solder pads 106, and the second protective layer 302a in the cover structure 30a are formed simultaneously by a semiconductor process. Then, the conductive layer 50a covers a portion of the surface of the first protective layer 40, a portion of the surface of the plurality of pads 106 not covered by the first protective layer 40, and an outer surface 34a of the cover structure 30a and a portion of the upper surface 36a of the cover structure 30a. In one embodiment, the conductive layer 50a is composed of an under bump metallurgy (UBM) 502a and a redistribution layer (RDL) 504a, wherein the redistribution layer 504a is disposed on the under bump metallurgy 502a. Specifically, the under-bump metal layer 502a as the conductive layer 50a covers a portion of the surface of the first protective layer 40, a portion of the surface of the plurality of pads 106 not covered by the first protective layer 40, an outer surface 34a of the cover structure 30a, and a portion of the upper surface 36a of the cover structure 30a. Then, the redistribution layer 504a as the conductive layer 50a is disposed on the under-bump metal layer 502a. Finally, a plurality of bumps 60 are disposed on the conductive layer 50a covering the upper surface 36a of the cover structure 30a to complete the acoustic wave element 1. In one embodiment, the bump 60 can be a copper pillar bump, a copper pillar, or a C4 bump. In addition, it should be noted that the formation method of the acoustic wave element 1 in the present invention is to use the existing semiconductor process technology. The process flow and the materials constituting the acoustic wave element 1 are not included in the technical solution to be discussed in the present invention, so they will not be described in detail.

Next, the present invention also discloses another acoustic wave element, as shown in FIG2. FIG2 is a cross-sectional schematic diagram showing another embodiment of an acoustic wave element according to the technology disclosed in the present invention. In FIG2, the acoustic wave element 2 is composed of a substrate 10, an electronic element 20, a cover structure 30b, a first protective layer 40, a conductive layer 50b and a plurality of bumps 60. The substrate 10 has an upper surface 102 and a lower surface 104, and a plurality of solder pads 106 are provided around the upper surface 102. The materials of the substrate 10, the solder pads 106 and the electronic element 20 are the same as those described above and are not further described. The electronic element 20 is provided on the upper surface 102 of the substrate 10, so that the plurality of solder pads 106 around the upper surface 102 of the substrate 10 surround the electronic element 20.

Please continue to refer to Figure 2. A cover structure 30b is provided above the substrate 10 having the electronic component 20. The space between the cover structure 30b and the substrate 10 can be defined as a closed cavity 32b, so the electronic component 20 on the upper surface 102 of the substrate 10 is disposed in the closed cavity 32b. The cover structure 30b can prevent moisture in the external environment from entering the closed cavity 32b, thereby increasing the service life of the electronic component 20 and the reliability of the entire acoustic wave element 2 through the cover structure 30b.

In another embodiment of the present invention, the cover structure 30b includes, from the substrate 10 upward, a second protective layer 302b, a first insulating layer 304b, and a second insulating layer 306b, wherein the second protective layer 302b covers a portion of the surface of the plurality of pads 106 adjacent to the electronic element 20, and the second protective layer 302b is disposed on a portion of the upper surface 102 of the substrate 10 adjacent to the electronic element 20. The first insulating layer 304b is disposed on a portion of the surface of the second protective layer 302b and covers a portion of the surface of the plurality of pads 106, and the second protective layer 302b and the first insulating layer 304b above the substrate 10 do not cover the electronic element 20 on the substrate 10. The second insulating layer 306b covers a portion of the surface of the first insulating layer 304b, so that the structure formed by the second protective layer 302b and the first insulating layer 304b is defined as the side wall of the cover structure 30b and the second insulating layer 306b is the top wall of the cover structure 30b. Similarly, in one embodiment, the second insulating layer 306b and the first insulating layer 304b in the cover structure 30b are in a stepped structure.

Please continue to refer to FIG. 2. The acoustic wave element 2 further includes a first protective layer 40, which covers a portion of the upper surface 102 of the substrate 10 and a portion of the surface of the plurality of solder pads 106, and exposes other portions of the surface of the plurality of solder pads 106, that is, portions of the surface of the plurality of solder pads 106 not covered by the first protective layer 40. It should be noted that the first protective layer 40 covering a portion of the upper surface 102 of the substrate 10 and covering a portion of the surface of the plurality of solder pads 106, and exposing other portions of the surface of the plurality of solder pads 106, and the second protective layer 302b in the cover structure 30b are formed simultaneously by a semiconductor process. Then, the conductive layer 50b covers a portion of the surface of the first protective layer 40, a portion of the surface of the plurality of pads 106 not covered by the first protective layer 40, and an outer surface 34b of the cover structure 30b and a portion of the upper surface 36b of the cover structure 30b. In one embodiment, the conductive layer 50b is composed of an under bump metal layer 502b and a redistribution layer 504b, wherein the redistribution layer 504b is disposed on the under bump metal layer 502b. Specifically, the under-bump metal layer 502b as the conductive layer 50b covers a portion of the surface of the first protective layer 40, a portion of the surface of the plurality of pads 106 not covered by the first protective layer 40, an outer surface 34b of the cover structure 30b, and a portion of the upper surface 36b of the cover structure 30b. Then, the redistribution layer 504b as the conductive layer 50b is disposed on the under-bump metal layer 502b. Finally, a plurality of bumps 60 are disposed on the conductive layer 50b covering the upper surface 36b of the cover structure 30b to complete the acoustic wave element 2. In one embodiment, the bump 60 can be a copper pillar bump, a copper pillar, or a C4 bump. . In addition, it should be noted that the formation method of the acoustic wave element 2 in the present invention is to use the existing semiconductor process technology. The process flow and the materials constituting the acoustic wave element 10 are not included in the technical solution to be discussed in the present invention, so they will not be described in detail.

In addition, the present invention discloses another acoustic wave element, as shown in FIG3. FIG3 is a cross-sectional schematic diagram showing another embodiment of an acoustic wave element according to the technology disclosed in the present invention. In FIG3, the acoustic wave element 2 is composed of a substrate 10, an electronic element 20, a cover structure 30c, a first protective layer 40, a conductive layer 50c and a plurality of bumps 60. The substrate 10 has an upper surface 102 and a lower surface 104, and a plurality of solder pads 106 are provided around the upper surface 102. The materials of the substrate 10, the solder pads 106 and the electronic element 20 are the same as those described above and are not further described. The electronic element 20 is provided on the upper surface 102 of the substrate 10, so that the plurality of solder pads 106 around the upper surface 102 of the substrate 10 surround the electronic element 20.

Please continue to refer to Figure 3. A cover structure 30c is provided above the substrate 10 having the electronic component 20. The space between the cover structure 30c and the substrate 10 can be defined as a closed cavity 32c, so the electronic component 20 on the upper surface 102 of the substrate 10 is disposed in the closed cavity 32c. The cover structure 30c can prevent moisture in the external environment from entering the closed cavity 32c, thereby increasing the service life of the electronic component 20 and the reliability of the entire acoustic wave element 3 through the cover structure 30c.

In another embodiment of the present invention, the cover structure 30c includes, from the substrate 10 upward, a second protective layer 302c, a first insulating layer 304c, and a second insulating layer 306c, wherein the second protective layer 302c covers a portion of the surface of the plurality of pads 106 adjacent to the electronic element 20, and the second protective layer 302c is disposed on a portion of the upper surface 102 of the substrate 10 adjacent to the electronic element 20. The first insulating layer 304c is disposed on a portion of the surface of the second protective layer 302c and covers a portion of the surface of the plurality of pads 106, and the second protective layer 302c and the first insulating layer 304c above the substrate 10 do not cover the electronic element 20 on the substrate 10. The second insulating layer 306c covers part of the surface of the first insulating layer 304c, so that the structure formed by the second protective layer 302c and the first insulating layer 304c is defined as the side wall of the cover structure 30c and the second insulating layer 306b is the top wall of the cover structure 30c. Similarly, in one embodiment, the second insulating layer 306c and the first insulating layer 304c in the cover structure 30c are in a stepped structure.

Please continue to refer to FIG. 3. The acoustic wave element 3 further includes a first protective layer 40, which covers a portion of the upper surface 102 of the substrate 10 and a portion of the surface of the plurality of solder pads 106, and exposes other portions of the surface of the plurality of solder pads 106, that is, the portions of the surface of the plurality of solder pads 106 not covered by the first protective layer 40. It should be noted that the first protective layer 40, which covers a portion of the upper surface 102 of the substrate 10 and a portion of the surface of the plurality of solder pads 106, and exposes other portions of the surface of the plurality of solder pads 106, and the second protective layer 302c in the cover structure 30c are formed simultaneously by a semiconductor process. Next, the first insulating layer 304c is disposed on a portion of the surface of the first protective layer 40 and covers a portion of the surface of the plurality of solder pads 106 to expose a portion of the surface of the plurality of solder pads 106 not covered by the first protective layer 40. It should be noted that the first insulating layer 304c disposed on a portion of the surface of the first protective layer 40 and covering a portion of the surface of the plurality of solder pads 106 and the first insulating layer 304c in the cover structure 30c are formed simultaneously using the same semiconductor process and both have the same height.

Next, the conductive layer 50c is covered on a portion of the surface of the first insulating layer 304c, a portion of the surface of the plurality of pads 10 not covered by the first protective layer 40, an outer surface 34c of the cover structure 30c, and a portion of the upper surface 36c of the cover structure 30c. In one embodiment, the conductive layer 50c is composed of an under bump metal layer (UBM) 502c and a redistribution layer 504c, wherein the redistribution layer 504c is disposed on the under bump metal layer 502c. Specifically, the metal layer under the bump 502c of the conductive layer 50c is first formed on a portion of the surface of the first insulating layer 304c, a portion of the surface of the plurality of pads 106 not covered by the first protective layer 40, the outer surface 34c of the cover structure 30c, and a portion of the upper surface 36c of the cover structure 30c. Then, the redistribution layer 504c of the conductive layer 5c0 is disposed on the metal layer under the bump 502c. Finally, a plurality of bumps 60 are disposed on the conductive layer 50c covering the upper surface 36c of the cover structure 30c to complete the acoustic wave element 3. In one embodiment, the bump 60 can be a copper pillar bump, a copper pillar, or a C4 bump.

In summary, according to the acoustic wave components 1, 2, 3 disclosed in the present invention, in the subsequent flip chip assembly process, the conductive layers 50a, 50b, 50c are used during the mold flow process to increase the strength between the bump 60 and the solder pad 106, so as to solve the problem that when the acoustic wave components 1, 2, 3 are packaged in a flip chip manner, the bump 60 will be broken due to stress and the solder pad 106 will be pulled up from the substrate 10, causing the entire package structure to be damaged. In addition, the cover structures 30a, 30b in FIG. 1 and FIG. 2 and the cover structure 30c in FIG. 3 and the first insulating layer 304c disposed on a portion of the surface of the first protective layer 40 and covering a portion of the surface of the plurality of pads 106 can prevent moisture from the external environment from entering the cavities 32a, 32b, 32c to increase the reliability of the acoustic wave elements 1, 2, 3 as a whole during operation.

1: Acoustic wave components

10: Substrate

102: Upper surface

104: Lower surface

106: Welding pad

20: Electronic components

30a: Cover structure

302a: Second protection layer

304a: First insulating layer

306a: Second insulating layer

32a: Closed cavity

34a: Outer surface

36a: Upper surface

40: First protective layer

50a: Conductor layer

502a: metal layer under the bump

504a: Rewiring layer

60: Bump

Claims (10)

An acoustic wave element comprises: a substrate having an upper surface and a lower surface, and a plurality of solder pads are arranged on the periphery of the upper surface; at least one electronic component is arranged on the upper surface of the substrate, so that the solder pads on the periphery of the upper surface of the substrate surround the electronic component; a cover structure, the cover structure having a second protective layer, a first insulating layer and a second insulating layer, the cover structure is arranged above the substrate having the electronic component, and a space between the cover structure and the substrate is defined as a closed type The invention relates to a closed cavity, wherein the electronic element is arranged in the closed cavity; a first protective layer covering a part of the upper surface of the substrate and a part of the surface of the solder pads, and exposing a part of the surface of the solder pads not covered by the first protective layer; a conductive layer covering a part of the surface of the first protective layer, a part of the surface of the solder pads not covered by the first protective layer, an outer surface of the cover structure and a part of the upper surface of the cover structure; and a plurality of bumps arranged on the conductive layer located on the upper surface of the cover structure. The acoustic wave device as claimed in claim 1, wherein the cover structure comprises, in order from the substrate upward, the second protective layer, which simultaneously covers a portion of the surface of the pads adjacent to the electronic component and is disposed on the upper surface of the substrate adjacent to the electronic component; the first insulating layer, which is disposed on a portion of the surface of the second protective layer, The second protective layer and the first insulating layer do not cover the electronic component on the substrate; and the second insulating layer covers a portion of the surface of the first insulating layer, so that a structure formed by the second protective layer and the first insulating layer is defined as a side wall of the cover structure and the second insulating layer is a top wall of the cover structure. The acoustic wave device as claimed in claim 1, wherein the cover structure includes, in order from the substrate upward, the second protective layer, the second protective layer simultaneously covering a portion of the surface of the solder pads adjacent to the electronic component and disposed on the upper surface of the substrate adjacent to the electronic component; the first insulating layer, disposed on a portion of the surface of the second protective layer and covering a portion of the surface of the solder pads to expose the portions not covered by the second protective layer; The first insulating layer covers a portion of the surface of the solder pads, and the second protective layer and the first insulating layer do not cover the electronic components on the substrate; and the second insulating layer covers a portion of the surface of the first insulating layer, so that a structure formed by the second protective layer and the first insulating layer is defined as a side wall of the cover structure and the second insulating layer is a top wall of the cover structure. An acoustic wave element comprises: a substrate having an upper surface and a lower surface, and a plurality of solder pads are arranged on the periphery of the upper surface; at least one electronic element is arranged on the upper surface of the substrate, so that the solder pads on the periphery of the upper surface of the substrate surround the electronic element; a cover structure is arranged above the substrate having the electronic element, and a space between the cover structure and the substrate is defined as a closed cavity, so that the electronic element is arranged in the closed cavity; a first protective layer covering the substrate A first insulating layer is disposed on a portion of the surface of the first protective layer and covers a portion of the surface of the solder pads to expose a portion of the surface of the solder pads not covered by the first protective layer; a conductive layer covers a portion of the surface of the first insulating layer, a portion of the surface of the solder pads not covered by the first protective layer, an outer surface of the cover structure and a portion of the upper surface of the cover structure; and a plurality of bumps are disposed on the conductive layer located on the upper surface of the cover structure. The acoustic wave device as described in claim 4, wherein the cover structure includes, from the substrate upward, a second protective layer, the second protective layer simultaneously covers a portion of the surface of the solder pads adjacent to the electronic component and is disposed on the upper surface of the substrate adjacent to the electronic component; the first insulating layer, disposed on a portion of the surface of the second protective layer and covering a portion of the surface of the solder pads to expose a portion of the solder pads not covered by the first insulating layer; The second protective layer and the first insulating layer do not cover the electronic components on the substrate, and the second protective layer and the first insulating layer do not cover the electronic components on the substrate; and a second insulating layer covers a portion of the surface of the first insulating layer, so that a structure formed by the second protective layer and the first insulating layer is defined as a side wall of the cover structure and the second insulating layer is a top wall of the cover structure. The acoustic wave element as described in claim 2, 3 or 5, wherein the second insulating layer and the first insulating layer of the cover structure are in a stepped structure. The acoustic wave element as described in claim 5, wherein the height of the first insulating layer disposed on part of the surface of the first protective layer and covering part of the surface of the pads is the same as the height of the first insulating layer of the cover structure. An acoustic wave element as described in claim 1 or 4, wherein the conductor layer is composed of an under bump metallurgy (UBM) and a redistribution layer (RDL), wherein the redistribution layer is disposed on the under bump metallurgy. An acoustic wave element as described in claim 1 or 4, wherein the electronic element can be a filter, an oscillator or a sensor. An acoustic wave element as described in claim 1 or 4, wherein the bump can be a copper pillar bump, a copper pillar or a C4 bump.

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