CN-122026852-A - Elastic wave device and manufacturing method thereof

Abstract

The invention relates to an elastic wave device, which comprises a device chip with a functional surface, wherein the functional surface is one surface containing a circuit pattern for forming a resonator, and a packaging substrate, one surface of the packaging substrate is a mounting surface of the device chip, the device chip is integrally mounted on the packaging substrate, a gap is formed between the functional surface and the mounting surface, the area of the functional surface is larger than that of the mounting surface when being observed from a direction perpendicular to the functional surface and the mounting surface, the outer edge of the mounting surface is positioned at any position inside the outer edge of the functional surface, so that a sealing area which is not overlapped with the mounting surface and is used for sealing is formed on the outer edge side of the functional surface, a base part is fixed on the sealing area, and a sealing part formed by insulating resin is used for fixing the inner side part of the sealing area to the side surface of the packaging substrate, and the sealing part enables the inner side of the sealing area to form an inner space.

Inventors

• ODA YASUYUKI
• NAKAMURA HIROBUMI

Assignees

• 三安日本科技株式会社

Dates

Publication Date

20260512

Application Date

20251111

Priority Date

20241111

Claims (10)

1. 1. An elastic wave device, comprising: a device chip having a functional surface, the functional surface being a surface including a circuit pattern forming a resonator; And a package substrate, one surface of which is a mounting surface of the device chip, The device chip is integrally mounted on the packaging substrate, a gap is formed between the functional surface and the mounting surface, The functional surface has an area larger than that of the mounting surface when viewed from a direction perpendicular to the functional surface and the mounting surface, and an outer edge of the mounting surface is located inside an outer edge of the functional surface at an arbitrary position, so that a sealing area for sealing is formed on an outer edge side of the functional surface without overlapping the mounting surface, The sealing region for sealing is fixed with a base portion, and a sealing portion made of an insulating resin fixes an inner side portion thereof to a side surface of the package substrate, the sealing portion forming an inner space inside the sealing region.
2. 2. An elastic wave device according to claim 1, wherein wiring constituting a part of the circuit pattern or a functional device other than the resonator is provided in the sealing region.
3. 3. An acoustic wave device according to claim 1, wherein the outer side of the seal is flush with the side of the device chip.
4. 4. An elastic wave device according to claim 3, wherein a part of the inner side portion of said sealing portion enters into said gap.
5. 5. The elastic wave device according to claim 1, wherein the circuit pattern is covered with an insulating film, and the base portion of the sealing portion is fixed to the sealing region through the insulating film.
6. 6. The elastic wave device according to claim 1, wherein the outer side of the sealing portion is located inside the side face of the device chip.
7. 7. An elastic wave device according to claim 1, wherein the inner side portion of the sealing portion covers the entire side surface of the device chip.
8. 8. The method for manufacturing an elastic wave device according to any one of claims 1 to 7, comprising: step 1, forming the circuit patterns in each unit area serving as the device chip on a wafer; step 2, after the step 1, mounting the package substrate in each of the unit areas on the wafer; step 3, after the step 2, forming the sealing part in an edge region formed between the adjacent package substrates on the wafer; and 4, after the 3 rd step, cutting and dividing the wafer in the edge area, thereby generating a plurality of elastic wave devices corresponding to the number of the unit areas.
9. 9. The method of manufacturing an acoustic wave device according to claim 8, wherein in the step 4, the sealing portion is cut together with the wafer.
10. 10. The method of manufacturing an acoustic wave device according to claim 8, wherein in the 3 rd step, the sealing portions are formed using an inkjet printer at both sides sandwiching the widthwise middle position of the edge region, respectively, and in the 4 th step, the wafer is cut at the widthwise middle position of the edge region.

Description

Elastic wave device and manufacturing method thereof Technical Field The present invention relates to an improvement of an elastic wave device suitable for use as a frequency filter or the like in a mobile communication device. Background The elastic wave device having CSP (Chip Size Package) structure has a structure as shown in fig. 20. In the figure, reference numeral 100 denotes a device chip, at least one surface of which is made of a piezoelectric material as a functional surface, reference numeral 101 denotes a resonator, which is formed of a metal film on the one surface 102 of the device chip 100, and reference numeral 103 denotes a package substrate. The device chip 100 is mounted on the package substrate 103 through bumps 104. A space is formed between the device chip 100 and the package substrate 103 by the bump 104. On the mounting side of the device chip 100 in the package substrate 103, a sealing resin 105 is formed to cover the other surface corresponding to the one surface 102 of the device chip 100 and the side surface thereof. The elastic wave device is provided with an internal space 106 between the package substrate 103 and the one surface 102 of the device chip 100 by the sealing resin 105. The resonator 101 is located in this inner space 106. The elastic wave device has a hexahedral structure with two rectangular faces 107 parallel to the one face 102 and four side faces 108. The dimensions of the elastic wave device have been standardized, with the dimensions of the face 107 typically being 1.6mm by 1.2mm, 1.8mm by 1.4mm, 2.0mm by 1.6mm, 2.5mm by 2.0mm, and being widely circulated. However, the conventional elastic wave device has the above-described structure, and the size thereof is determined by the package substrate 103. The device chip 100 is smaller than the package substrate 103 and therefore the area of one side 102 is also smaller than the area of the side 107. Disclosure of Invention The main problem that the present invention seeks to solve is to provide a new structure for an elastic wave device of this type of CSP structure, which maximizes the area of the functional surface of the device chip that constitutes the device. In order to solve the above-described problems, the present invention proposes, from a first aspect, an elastic wave device including: The elastic wave device includes a device chip having one face as a functional face on which a circuit pattern including a resonator is formed; The device chip is integrally arranged on a packaging substrate, one surface of the packaging substrate is a mounting surface of the device chip, a space is formed between the functional surface and the mounting surface, The area of the functional surface is larger than the area of the mounting surface when seen from the direction perpendicular to the functional surface and the mounting surface, and the outer edge of the mounting surface is positioned inside the outer edge of the functional surface at any position, so that a sealing area for sealing which is not overlapped with the mounting surface is formed on the outer edge side of the functional surface, The sealing region for sealing is fixed with a base portion, and a sealing portion made of an insulating resin fixes an inner side portion thereof to a side surface of the package substrate, the sealing portion forming an inner space inside the sealing region. In one embodiment of the present invention, wiring constituting a part of the circuit pattern or a functional device other than the resonator is provided in the sealing region. In another embodiment of the invention, the outer portion of the seal is made flush with the side of the device chip. In one embodiment of the present invention, a part of the inner side portion of the seal portion enters the gap. In one embodiment of the present invention, the circuit pattern is covered with an insulating film, and the base portion of the sealing portion is fixed to the sealing region by the insulating film. In one embodiment of the present invention, the outer side of the sealing portion is located inside the side surface of the device chip. In one embodiment of the present invention, the inner side of the sealing portion covers the entire side of the device chip. In order to solve the above-described problems, the present invention proposes, from a second aspect, a method for manufacturing an elastic wave device, comprising the steps of: Step 1, forming the circuit patterns in each unit area serving as the device chip on a wafer; Step 2, after the step 1, mounting the package substrate in each unit area of the wafer; Step 3, after the step 2, forming the sealing part in an edge area formed between adjacent package substrates on the wafer; And 4, after the 3 rd step, cutting and dividing the wafer at the edge area, thereby generating a plurality of elastic wave devices corresponding to the number of the unit areas. In one embodiment of the present invention, in the step 4, the w