MEMS package, MEMS microphone and method of manufacturing the MEMS package
10863282 ยท 2020-12-08
Assignee
Inventors
- Koichi Shiozawa (Hong Kong, HK)
- Masashi Shiraishi (Hong Kong, HK)
- Jumpei Tsuchiya (Hong Kong, HK)
- Lik Hang Ken Wan (Hong Kong, HK)
- Toyotaka Kobayashi (Hong Kong, HK)
- Hironobu Hayashi (Hong Kong, HK)
Cpc classification
H04R1/04
ELECTRICITY
B81C1/00309
PERFORMING OPERATIONS; TRANSPORTING
B81B2201/0257
PERFORMING OPERATIONS; TRANSPORTING
H04R1/02
ELECTRICITY
B81C2203/0109
PERFORMING OPERATIONS; TRANSPORTING
B81B2207/115
PERFORMING OPERATIONS; TRANSPORTING
B81B2207/012
PERFORMING OPERATIONS; TRANSPORTING
B81B7/0061
PERFORMING OPERATIONS; TRANSPORTING
B81C2203/0792
PERFORMING OPERATIONS; TRANSPORTING
International classification
H04R1/04
ELECTRICITY
B81B7/00
PERFORMING OPERATIONS; TRANSPORTING
B81C1/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A MEMS package has a MEMS chip, a package substrate which the MEMS chip is adhered, a chip-cover which wraps the MEMS chip, and a cover-supporting part which supports the chip-cover from the inside. In the MEMS package, the chip-cover is supported by the cover-supporting part to form a back chamber, surrounded by the chip-cover and the package substrate.
Claims
1. A MEMS package comprising: a MEMS chip, a package substrate which the MEMS chip is adhered, a chip-cover which wraps the MEMS chip and a cover-supporting part which supports the chip-cover from the inside; wherein the chip-cover is adhered to the package substrate, wherein the cover-supporting part is adhered to the package substrate, wherein the chip-cover is supported by the cover-supporting part to form a back chamber, surrounded by the chip-cover and the package substrate, wherein the chip-cover is formed so as to be directly in contact with a chip-surface, being an outer surface of the MEMS chip, without being in contact with the package substrate between the cover-supporting part and the MEMS chip.
2. The MEMS package according to claim 1, further comprising: an ASIC package which is adhered to the package substrate in the back chamber.
3. The MEMS package according to claim 1, wherein the MEMS chip comprises an element substrate which a movable element is formed, wherein the element substrate comprises a hole-part which the movable element is arranged, wherein the chip-cover comprises a cover-hole-part formed in accordance with the hole-part.
4. The MEMS package according to claim 1, wherein the MEMS chip is mounted on the package substrate by a FCB, wherein the chip-cover is formed so as to be directly in contact with the side surface of the MEMS chip.
5. The MEMS package according to claim 1, wherein the chip-cover comprises a slanting part, being formed so as to bridge the cover-supporting part and the MEMS chip.
6. A MEMS microphone comprising: a MEMS package, and a cap which wraps the MEMS package, wherein the MEMS package comprises a MEMS chip, a package substrate which the MEMS chip is adhered, a chip-cover which wraps the MEMS chip and a cover-supporting part which supports the chip-cover from the inside; wherein the chip-cover is adhered to the package substrate, wherein the cover-supporting part is adhered to the package substrate, wherein the chip-cover is supported by the cover-supporting part to form a back chamber, surrounded by the chip-cover and the package substrate.
7. The MEMS microphone according to claim 6, wherein the cap comprises a top-surface, which is formed so as to oppose to the package substrate, and a cap-side-surface, which surrounds the top-surface and adhered to the package substrate, wherein the MEMS microphone further comprising a front chamber which is formed between the top-surface, the cap-side-surface and the chip-cover.
8. The MEMS microphone according to claim 7, wherein the MEMS chip comprises an element substrate which a movable element is formed, wherein the element substrate comprises a hole-part which the movable element is arranged, wherein the chip-cover comprises a cover-hole-part formed in accordance with the hole-part.
9. The MEMS microphone according to claim 8, wherein the top-surface comprises a top-hole which is formed in the position in accordance with the cover-hole-part.
10. The MEMS microphone according to claim 7, wherein the cap-side-surface comprises a side-hole which is formed in the position in accordance with the side surface of the MEMS chip.
11. The MEMS microphone according to claim 6, further comprising: an ASIC package which is adhered to the package substrate in the back chamber.
12. A MEMS package comprising: a MEMS chip, a package substrate which the MEMS chip is adhered, a chip-cover which wraps the MEMS chip and a cover-supporting part which supports the chip-cover from the inside; wherein the chip-cover is adhered to the package substrate, wherein the cover-supporting part is adhered to the package substrate, wherein the chip-cover is supported by the cover-supporting part to form a back chamber, surrounded by the chip-cover and the package substrate, wherein the MEMS package further comprises an ASIC package which is adhered to the package substrate in the back chamber, wherein the cover-supporting part comprises an open-covered-structure which includes a wall-like side-part and a lid-part, wherein the wall-like side-part extends along with a surface intersecting direction of the package substrate, and the MEMS chip side is opened, wherein the lid-part is formed in an upper end part of the wall-like side-part, wherein the ASIC package is arranged under the lid-part.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE EMBODIMENTS
(22) In the following, embodiments of the present invention will be described with reference to the drawings. Note that the same components will be referred to with the same numerals or letters, while omitting their overlapping descriptions.
(23) (Structure of the MEMS Package, MEMS Microphone)
(24) To begin with, the structure of the MEMS package 1, MEMS microphone 100, according to the embodiment of the present invention will be explained with reference to
(25)
(26) As illustrated in
(27) The MEMS package 1 has the MEMS chip 10, the package substrate 20, which the MEMS chip 10 is adhered, bonding bumps 4, a chip-cover 25 and the cover-supporting part 30. The MEMS chip 10 and the ASIC 92 are mounted on the package substrate 20 by the FCB, in the MEMS package 1.
(28) The MEMS chip 10 has an element substrate 2 which the membrane 3, as a movable element, is formed. The MEMS chip 10 is used as the microphone of capacitance-type. The element substrate 2 is a substrate formed in a rectangular-shape in a plan view, as illustrated in
(29) As illustrated in
(30) The membrane 3 is vibration film formed approximately in a circular-shape, and it is a thin-film made of an inorganic metal such as SiO.sub.2, SiN or the like.
(31) The bonding bumps 4 are solder bumps made of solder. As illustrated in
(32) The four bonding bumps 4 connect the MEMS chip 10 electrically and fixedly to the package substrate 20.
(33) The chip-cover 25 is supported by the cover-supporting part 30 and wraps the MEMS chip 10. The chip-cover 25 is a thin-film like member, and it is in contact with closely the MEMS chip 10 (a side surface 2d, a chip-surface 2b) and the whole surface of the cover-supporting part 30 (a later-described wall-like side-part 30a and a lid-part 30b), and it is formed so as to wrap them. Further, the peripheral part of the chip-cover 25 is adhered to the package substrate 20. For example, the chip-cover 25 is formed using high heat-resistant adhesive sheet with epoxy resin.
(34) Then, as illustrated in
(35) The chip-cover 25 has a cover-hole-part 25a. The cover-hole-part 25a is formed in about the center of a chip-corresponding part 25A. The chip-corresponding part 25A is a part, of the chip-cover 25, arranged on the upper side of the MEMS chip 10 (on the chip-surface 2b of the element substrate 2). The cover-hole-part 25a is formed in a circular shape in accordance with the hole-part 2c. The cover-hole-part 25a is formed in a position in accordance with the hole-part 2c. Further, both centers are overlapped, they have the same diameter, the cover-hole-part 25a is formed so as to communicate with the hole-part 2c.
(36) The cover-supporting part 30 is adhered to the package substrate 20. The cover-supporting part 30, as illustrated in
(37) Then the cover-supporting part 30 has, as illustrated in
(38) The wall-like side-part 30a is a wall like member which extends from the package surface 20a of the package substrate 20 along with the intersecting direction of the package surface 20a. The wall-like side-part 30a is formed U-shaped with all corners in approximate right angles, or it is formed square bracket like shape, surrounding the ASIC package 91 from three directions. The MEMS chip 10 side of the wall-like side-part 30a is opened. The end part of the opened side is the opened end-part 30c. As illustrated in
(39) The lid-part 30b is formed on the upper end part of the wall-like side-part 30a. The lid-part 30b is formed in a board-like shape having rectangular shape in a plan view, as illustrated in
(40) Then as illustrated in
(41) Further, the cover-supporting part 30 is arranged entirely outside the MEMS chip 10 (element substrate 2). The cover-supporting part 30 is arranged so that the opened end-part 30c is adjacent to the MEMS chip 10.
(42) The ASIC package 91 has the ASIC 92, the package substrate 20 which the ASIC 92 is adhered, and the bonding bumps 93. The ASIC 92, for example, is an integral circuit which amplifies an output signal of the MEMS chip 10 (an integral circuit which outputs displacement of a capacitance as displacement of the voltage in the MEMS chip 10). Electrode pads 14 are formed lower side of the ASIC 92. The electrode pads 14 are connected to the electrode pads 12 of the package surface 20a by the bonding bumps 93.
(43) The package substrate 20 is a board like member made of such as silicon, ceramic or the like (or PCB: Printed Circuit Board). The electrode pads 21 and electrode pads 12 are formed on the package surface 20a of the package substrate 20. The MEMS package 1 is mounted on the part, of the package surface 20a, which the electrode pads 21 are formed, the ASIC package 91 is mounted on the part which the electrode pads 12 are formed.
(44) The cap 99 covers the MEMS package 1 and the ASIC package 91. The cap 99 is adhered to the package surface 20a with not illustrated adhesive (or by soldering).
(45) There is an inner-volume inside of the cap 99, and the MEMS package 1 and the ASIC package 91 are accommodated in the inner-volume.
(46) The cap 99 has a top-surface 99E and a cap-side-surface 99F. The top-surface 99E is a part which is formed so as to oppose to the package substrate 20. The cap-side-surface 99F is a part which is formed on the peripheral part of the top-surface 99E. The cap-side-surface 99F surrounds the top-surface 99E, and it is adhered to the package substrate 20.
(47) In the MEMS microphone 100, a top-hole 99B is formed in the top-surface 99E. The top-hole 99B is a hole-part having a circular shape, and it is arranged in the position in accordance with the cover-hole-part 25a.
(48) Then, in the MEMS microphone 100, the second closed-space, which is surround by the top-surface 99E, the cap-side-surface 99F of the cap 99 and the chip-cover 25, is formed. The second closed-space is a space which is arranged inside more than the cap 99, and outside more than the chip-cover 25. The second closed-space corresponds to a front chamber 99A, because it is arranged front side than the membrane 3.
(49) (Method of Manufacturing the MEMS Package, MEMS Microphone)
(50) Subsequently, the method of manufacturing the MEMS package 1 and the MEMS microphone 100, having the above structure, will be explained with reference to
(51) In the Method of manufacturing the MEMS package 1, the MEMS package 1 is manufactured using the above-mentioned MEMS chip 10, the ASIC 92 and the package substrate 20. In case of the method of manufacturing according to the embodiment, the MEMS chip 10 (rectangular MEMS chip), having the rectangular element substrate 2, is used. Further, the package-panel 40, illustrated in
(52) The package-panel 40 is a board-like member, having rectangular shape, made of PCB or ceramic, and plural package-regions 41 are formed on the surface 40a by a uniform arrangement. When the package-panel 40 is divided along with divided lines 42, the package substrate 20 is manufactured from each package region 41 (about 600 package substrates 20 are manufactured by every package-panel 40).
(53) A mounting step, a cover-supporting part manufacturing step, a cover-supporting part adhering step, a chip-cover forming step and a removing step are included in the method of manufacturing the MEMS package 1.
(54) In the mounting step, the MEMS chip 10 and the ASIC 92 are mounted in each of the package regions 41 of the package-panel 40. In this case, in the MEMS chip 10, the four bonding bumps 4 are formed in the opposing surface 2a side. In the ASIC 92, bonding bumps 93 are formed. After that, as illustrated in
(55) Next, the cover-supporting part adhering step is performed. In the cover-supporting part adhering step, the above-described cover-supporting part 30 is adhered to each of the package regions 41.
(56) In the embodiment, the cover-supporting part manufacturing step is performed as follows, before performing the cover-supporting part adhering step. The cover-supporting part 30 is manufactured by performing the cover-supporting part manufacturing step.
(57) In the cover-supporting part manufacturing step, a thin-metal plate (for example, a metal plate having thickness about 50 m with SUS or phosphor bronze, in case of phosphor bronze, preferably Ni plating is applied) is used. Then, the metal plate is cut using the NC apparatus to form a metal-pattern 31 having the predetermined size. Bending procedure, with press apparatus, is performed to the metal-pattern 31 to form the cover-supporting part 30. As illustrated in
(58) Then, the cover-supporting part 30, which is manufactured as described-above, is adhered on each of the package regions 41 with adhesive. At this time, as illustrated in
(59) Next, the chip-cover forming step is performed. In the chip-cover forming step, a vacuum lamination is performed using a not-illustrated vacuum laminator. Then, the surface 40a of the package-panel 40 is covered with the high heat-resistant adhesive sheet with epoxy resin (not-illustrated). In this case, the MEMS chip 10 is mounted on each of the package regions 41 of the package-panel 40, the cover-supporting part 30 is adhered so as to be adjacent to the MEMS chip 10. Therefore, the high heat-resistant adhesive sheet is adhered to the surface of each of the MEMS chips 10 (chip-surface 2b, side surface 2d), and the surface of the cover-supporting part 30 without gap. Further, the package-panel 40 is heated to harden the high heat-resistant adhesive sheet. Thereby, the chip-cover 25 is formed.
(60) Subsequently, the removing step is performed. In the removing step, unnecessary parts of the high heat-resistant adhesive sheet are removed with laser. In this case, parts of the high heat-resistant adhesive sheet, arranged between each of the package regions 41 and corresponding to the hole-part 2c of the chip-cover 25, are removed. By the removing step, the cover-hole-part 25a is formed in the chip-cover 25.
(61) More subsequently, each of the package regions 41 of the package-panel 40 is covered with the cap 99. In this case, the top-hole 99B is previously formed in the cap 99. Therefore, the cap 99 is applied to each of the package regions 41 so that the top-hole 99B is arranged in the position in accordance with the cover-hole-part 25a.
(62) After that, a panel cutting step is performed. In the panel cutting step, the package-panel 40, which the MEMS chip 10 and the ASIC 92 are mounted, is cut along with the divided lines 42 to be divided into the respective package-regions 41. Then, the package-panel 40 is divided into the plural package-regions 41. The MEMS package 1 and the MEMS microphone 100 are manufactured together with the package substrate 20 from each of the package-regions 41.
(63) (Operation and Effect of the MEMS Package)
(64) As mentioned above, the MEMS chip 10 and the ASIC 92 are mounted on the package substrate 20, and the MEMS chip 10 is connected to the ASIC 92 on the package substrate 20, in the MEMS package 1 and the MEMS microphone 100. Wires along with up and down direction, like the conventional MEMS packages 290, 310 (see
(65) Further, the MEMS chip 10 is mounted on the package substrate 20, the top-hole 99B is formed in the cap 99, distant from the MEMS chip 10. The top-hole 99B is also able to be formed in the position, of the MEMS chip 10, distant from the hole-part 2c. Therefore, because position of the sound hole is able to be changed, generality, about the position of the sound hole, is high.
(66) Further, because sound, which enters from the top-hole 99B, reaches the MEMS chip 10 without bending, sound never decreases before getting to the MEMS chip 10. Therefore, lowering of the sensitivity is avoided, in the MEMS package 1 and the MEMS microphone 100.
(67) Further, in case of the MEMS package 1, the back chamber 99D is formed by the chip-cover 25. The cap 99 is mounted on the MEMS package 1, thereby, the front chamber 99A is formed to gain the MEMS microphone 100. Both the front chamber 99A and the back chamber 99D, having certain size, are secured, moreover, size balance is secured. Therefore, sensitivity of the MEMS microphone 100 is good.
(68) The cover-supporting part 30 is manufactured by press bending with the metal plate having thin thickness. Therefore, before the MEMS package 1 and the MEMS microphone 100 are manufactured, the cover-supporting part 30 is able to be formed previously. Further, because the cover-supporting part 30 is mounted with adhesive, the MEMS package 1 and the MEMS microphone 100 are easily manufactured.
(69) Further, the cover-supporting part 30 is able to be formed so that the supporting-height h30 is larger than the chip-height h2. Thereby, because the back chamber 99D is able to be secured largely, the cover-supporting part 30 is able to be formed with the structure according to demand characteristic.
First Modified Example
(70) Next, the cover-supporting part 35, according to a first modified example, is explained with reference to
(71) The cover-supporting part 35 is the same with the supporting part 30 in that it has the open-covered-structure, in compared with the cover-supporting part 30. However, the cover-supporting part 35 is different from the cover-supporting part 30 in that it has the wall-like side-part 35a, the lid-part 35b, the opened end-part 35c and a rear-surface part 35d.
(72) The wall-like side-part 35a is a wall-like member extended along with the intersecting direction from the package surface 20a, similar with the wall-like side-part 30a. The part, of the wall-like side-part 35a, opposing to the opened end-part 35c is the rear-surface part 35d. The rear-surface part 35d has an about half height of the wall-like side-part 35a or height smaller than the half height. Therefore, the rear-surface part 35d is partially opened.
(73) The cover-supporting part 35 surrounds the ASIC package 91 from three directions and it is able to support the chip-cover 25, similar with the cover-supporting part 30. Therefore, the MEMS package and MEMS microphone, which the cover-supporting part 35 is formed, has the same operation and effect with the MEMS package 1 and MEMS microphone 100. Especially, in case of the MEMS package 1A and the MEMS microphone 105, which the cover-supporting part 35 is formed, as illustrated in
Second Modified Example
(74) Next, the cover-supporting part 36, according to a second modified example, is explained with reference to
(75) The cover-supporting part 36 is the same in that it has the open-covered-structure, in compared with the cover-supporting part 35. However, the cover-supporting part 36 is different from the cover-supporting part 35 in that it has the wall-like side-part 36a, the lid-part 36b, the opened end-part 36c and the opened end-part 36e.
(76) The wall-like side-part 36a is a wall-like member extended along with the intersecting direction from the package surface 20a, similar with the wall-like side-part 35a. However, the part, of the wall-like side-part 36a, opposing to the opened end-part 36c is the opened end-part 36e, which is entirely opened.
(77) The cover-supporting part 36 surrounds the ASIC package 91 from two directions and it is able to support the chip-cover 25, similar with the cover-supporting part 30. Therefore, the MEMS package and MEMS microphone, which the cover-supporting part 36 is formed, has the same operation and effect with the MEMS package 1 and MEMS microphone 100. Especially, in case of the MEMS package 1B and the MEMS microphone 106, which the cover-supporting part 35 is formed, as illustrated in
Third Modified Example
(78) Next, the cover-supporting part 50 according to the third modified example will be explained with reference to
(79) The cover-supporting part 50 is different in that it has the lid-part 50b instead of the lid-part 30b, in compare with the cover-supporting part 30. The lid-part 30b is formed with board-like shape though, the lid-part 50b has a mesh-like structure.
(80) Because the cover-supporting part 50 has the open-covered-structure similar with the cover-supporting part 30, it surrounds the ASIC package 91 from three directions, and it is able to support the chip-cover 25. Therefore, the MEMS package and MEMS microphone, which the cover-supporting part 50 is formed, has the operation and effect similar with the MEMS package 1 and MEMS microphone 100.
Forth Modified Example
(81) Next, the MEMS microphone 102 according to the forth modified example will be explained with reference to
(82) The MEMS microphone 102 is different in that it has the cap 101 instead of the cap 99, in compare with the MEMS microphone 100.
(83) The cap 101 is different in the position of the sound hole, in compare with the cap 99. In case of the cap 99, the top-hole 99B is formed in the top-surface 99E. However, in case of the cap 101, a side-hole 101a, as the sound hole, is formed in the cap-side-surface 101F.
(84) In case of the above, because the front chamber 99A is formed between the cap 101 and the chip-cover 25, sensitivity of the MEMS microphone 102 is good. Because the MEMS microphone 102 has the same constitution with the MEMS microphone 100, it has the operation and effect similar with the MEMS microphone 100.
Fifth Modified Example
(85) Next, the MEMS microphone 103 according to the fifth modified example will be explained with reference to
(86) The MEMS microphone 103 is different in that it has the ASIC package 95 instead of the ASIC package 91, in compare with the MEMS microphone 100. In case of the ASIC package 95, the ASIC 92 is mounted on the package substrate 20 by the wire bonding using the wire 94.
(87) Because the MEMS microphone 103 has the same constitution with the MEMS microphone 100, it has the operation and effect similar with the MEMS microphone 100.
(88) The type double back-plate, having two not illustrated thin-films which are called back-plate are arranged in the upper side and the lower side of the membrane 3, is explained exemplarily in the embodiment. The present invention is also applicable to the type single back-plate, having one back-plate is arranged in the one side of the membrane 3.
(89) This invention is not limited to the foregoing embodiments but various changes and modifications of its components may be made without departing from the scope of the present invention. Besides, it is clear that various embodiments and modified examples of the present invention can be carried out on the basis of the foregoing explanation. Therefore, the present invention can be carried out in modes other than the above-mentioned best modes within the scope equivalent to the following claims.