TWM622683U - Isolated micro-electromechanical-systems microphone structure - Google Patents

Abstract

A separate MEMS microphone structure, through the combination of bonding, opening, laminating, copper etching, solder masking and forming process combination to make a substrate, an isolation layer is arranged on the substrate, the specific application of integrated circuit chips through the dispensing method Disposed on the substrate, the MEMS die is disposed at the second through hole of the substrate by dispensing, and a closed space is formed by the substrate, the isolation layer, the outer cover, and the MEMS die to form a closed cavity, whereby a closed cavity can be formed. The technical effect of providing a MEMS die to form a closed cavity structure is achieved.

Description

Separate MEMS Microphone Structure

A micro-electro-mechanical system microphone structure, especially a micro-electro-mechanical system microphone structure that provides a closed-cavity structure formed by micro-electro-mechanical system crystal grains.

MEMS die is a sensor or actuator that uses aluminum nitride (Aluminum Nitride, AlN) as a piezoelectric material, and is constantly developing in the direction of miniaturization and integration. lower the cost. The use of aluminum nitride material not only has good thermal conductivity, high dielectric constant, but also is compatible with complementary metal-oxide-semiconductor (Complementary Metal-Oxide-Semiconductor, CMOS) process; It has high electrical properties, good mechanical properties and optical transmission properties, simple manufacturing process and low cost, so it is widely used in industry, medicine and the like. The current industrialized commercial applications include thin-film bulk acoustic resonators, ultrasonic sensors, piezoelectric transducers, etc.

For the compact and complex aluminum nitride MEMS die, it is necessary to protect the moving parts inside the die to ensure the high performance index of the die. In order to avoid prolonged exposure to complex working environments, subsequent integrated packaging is also particularly important. At present, the main integrated packaging technology solutions are: InvenSense Company of the United States proposed a MEMS-IC monolithic integrated micro-electromechanical system wafer-level vacuum packaging technical solution, using thin-film bulk acoustic wave grains, ultrasonic sensors, etc. as the substrate, Application Specific Integrated Circuit (ASIC) signal processing integrated circuit (Integrated) Circuit, IC) is stacked on it, and the signal is led out by interconnecting through the through-silicon via (TSV) technology in its body. In recent years, most enterprises and research institutions have adopted Post-CMOS monolithic integrated technology, which is widely used in subsequent mass production manufacturing. The production of system grains realizes monolithic integrated MEMS. In 1960, IBM developed flip-chip packaging technology. Generally, a solder joint array is fabricated on the front side of the wafer as input and output terminals and soldered to the package substrate in an inverted manner, and the underfill organic material is used to stabilize the soldering and bonding process.

However, the wafer-level vacuum packaging technology based on TSV technology is highly complex and has a great impact on IC design. The area of the specific application IC and MEMS die needs to be consistent, and the IC technology is proportional The rate of shrinkage is much faster than that of MEMS technology, requiring the die area to be consistent between the two, resulting in wasted die area and increased cost. Although the Post-CMOS monolithic integrated technology has low requirements on the CMOS process, it will have a greater impact on the CMOS circuit when processing the aluminum nitride MEMS die at high temperature. Flip-chip technology cannot form aluminum nitride MEMS dice into closed-cell structures.

To sum up, it can be seen that in the prior art, there has been a problem that the flip-chip technology cannot form the MEMS die into a closed cavity structure for a long time. Therefore, it is necessary to propose an improved technical means to solve this problem.

In view of the problem that the flip-chip technology cannot form the MEMS die into a closed cavity structure in the prior art, the present invention discloses a separated MEMS microphone structure, wherein:

The isolated MEMS microphone structure of the first embodiment disclosed in the present invention includes: a substrate, an isolation layer, an Application Specific Integrated Circuit (ASIC) die, a Micro Electro Mechanical Systems (Micro Electro Mechanical Systems, MEMS) die and outer cover, the substrate further includes: a bottom plate, a first side plate, a second side plate and a cover plate.

A power supply circuit and a grounding circuit are embedded in the bottom plate, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the bottom plate as the power external connection point and the grounding external connection point; the first side plate is stacked on one end of the bottom plate, and the power supply circuit and the grounding circuit are embedded in the first side plate The second side plate is stacked on the other end of the bottom plate, the second side plate is embedded with a power circuit and a ground circuit; and the cover plate is stacked on the first side plate and the second side plate, the bottom plate, the first side plate, the second side plate and the cover plate An inner space is formed therebetween, the cover plate is provided with a first through hole and a second through hole between the first side plate and the second side plate, the inner space communicates with the outer space through the first through hole and the second through hole, and the cover The board is respectively embedded with a power supply line and a grounding line, and the power supply line and the grounding line are exposed on the top surface of the cover plate as a power supply contact and a grounding contact.

The isolation layer is formed by stacking on the substrate between the first through hole and the second through hole, and the space on one side of the isolation layer is defined as the first isolation space and the space on the other side of the isolation layer is defined as the second isolation space; specific The application integrated circuit die is disposed on the cover plate through glue dispensing and is located in the first isolation space, and the specific application integrated circuit die is electrically connected to the power supply contact and the ground contact through wire bonding technology; MEMS die The MEMS die is electrically connected to the power contact and the ground contact by means of glue dispensing; and the outer cover is covered on the cover plate and the isolation layer, and the outer cover and the ground contact To form an electrical connection, the outer cover is provided with an opening relative to the MEMS die, and a closed space is formed by the substrate, the isolation layer, the outer cover and the MEMS die to form a closed chamber, which is composed of the substrate, the isolation layer, the outer The lid and the MEMS die surround the open space to form an open cavity.

The isolated MEMS microphone structure of the second embodiment disclosed in the present invention includes a substrate, an isolation layer, an application-specific integrated circuit die, a MEMS die, and an outer cover. The substrate further includes: a bottom plate, a first A side panel, a second side panel and a cover panel.

A power supply circuit and a grounding circuit are embedded in the bottom plate, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the bottom plate as the power external connection point and the grounding external connection point; the first side plate is stacked on one end of the bottom plate, and the power supply circuit and the grounding circuit are embedded in the first side plate The second side plate is stacked on the other end of the bottom plate, the second side plate is embedded with a power circuit and a ground circuit; and the cover plate is stacked on the first side plate and the second side plate, the bottom plate, the first side plate, the second side plate and the cover plate An inner space is formed therebetween, the cover plate is provided with a first through hole and a second through hole between the first side plate and the second side plate, the inner space communicates with the outer space through the first through hole and the second through hole, and the cover The board is respectively embedded with a power supply line and a grounding line, and the power supply line and the grounding line are exposed on the top surface of the cover plate as a power supply contact and a grounding contact.

The specific application integrated circuit die is placed on the cover plate by means of dispensing, and the specific application integrated circuit die is electrically connected to the power contact and the ground contact respectively through wire bonding; the MEMS die is set by dispensing At the second through hole, the MEMS die is electrically connected to the power contact and the ground contact through a wire bonding technique; the isolation layer is stacked and attached to the MEMS die, and the isolation layer presents a hollow ring; and the outer The cover is covered on the cover plate and the isolation layer, the outer cover and the isolation layer are attached to each other, the outer cover and the ground contact are electrically connected, the outer cover is provided with an opening relative to the isolation layer, and the substrate, the isolation layer, the outer The cover and the MEMS die surround the closed space to form a closed cavity, and the hollow ring and the opening of the isolation layer form an open cavity.

The isolated MEMS microphone structure of the third embodiment disclosed in the present invention includes a substrate, an application-specific integrated circuit die, a MEMS die, an isolation layer, and an outer cover.

The substrate is provided with a conduction groove, the substrate is embedded with a power supply circuit and a grounding circuit, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the substrate as a power supply external connection point and a grounding external connection point, and the power supply circuit and the grounding circuit exposed on the top surface of the substrate are power supply contact points and Ground contact; the specific application integrated circuit die is placed on the substrate by dispensing, and the specific application integrated circuit die is electrically connected to the power contact and the ground contact respectively through wire bonding; MEMS die through point The glue is arranged at the conductive groove, and the MEMS die is electrically connected to the power contact and the ground contact through a wire bonding technique; the isolation layer is stacked and attached to the MEMS die, and the isolation layer presents a hollow ring; and The outer cover covers the substrate and the isolation layer, the outer cover and the isolation layer are attached to each other, the outer cover and the ground contact are electrically connected, and the outer cover is provided with an opening relative to the isolation layer, and the substrate, the isolation layer, and the outer cover are formed. The cover and the MEMS die surround the closed space to form a closed cavity, and the hollow ring and the opening of the isolation layer form an open cavity.

The structure disclosed in this creation is as above, and the difference between it and the prior art lies in that the substrate is formed by a combination of processes of bonding, opening, lamination, copper etching, solder masking and forming. The isolation layer is arranged on the substrate. The bulk circuit die is arranged on the substrate by means of dispensing, and the MEMS die is arranged at the second through hole of the substrate by means of dispensing, and the enclosed space is surrounded by the substrate, the isolation layer, the outer cover and the MEMS die. Form a closed chamber.

Through the above-mentioned technical means, the present invention can achieve the technical effect of providing the MEMS die to form a closed cavity structure.

10: Substrate

101: Interior Space

102: Power external point

103: Ground external point

104: Power contacts

105: Ground Contact

11: Bottom plate

111: Power external point

112: Ground external point

12: The first side panel

13: Second side panel

14: Cover

141: Power contact

142: ground contact

143: first through hole

144: second through hole

15: Conduction slot

20: isolation layer

201: First Isolation Space

202: Second Isolation Space

30: Application specific integrated circuit die

40: MEMS die

50: Outer cover

51: Opening

61: Close the chamber

62: Open Chamber

Step 701: A substrate is formed by combining the processes of bonding, hole opening, lamination, copper etching, solder masking and forming. The substrate is formed by stacking a bottom plate, a first side plate, a second side plate and a cover plate

Step 702: the first side plate is stacked on one end of the bottom plate, and the second side plate is stacked on the other end of the bottom plate

Step 703: The cover plate is stacked on the first side plate and the second side plate, an internal space is formed between the bottom plate, the first side plate, the second side plate and the cover plate, and the cover plate is interposed between the first side plate and the second side plate. A through hole and a second through hole, the inner space communicates with the outer space through the first through hole and the second through hole

Step 704 : a power supply circuit and a grounding circuit are embedded in the bottom plate, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the bottom plate as the power external connection point and the ground external connection point

Step 705 : the first side plate is embedded with power lines and ground lines, and the second side plate is embedded with power lines and ground lines

Step 706: The cover plate is respectively embedded with a power supply circuit and a grounding circuit, the power supply circuit exposed on the top surface of the cover plate is a power supply contact, and the grounding circuit exposed on the top surface of the cover plate is a grounding contact

Step 707: Stacking and forming an isolation layer on the substrate between the first through hole and the second through hole, defining the space on one side of the isolation layer as the first isolation space and defining the space on the other side of the isolation layer as the second isolation space

Step 708 : the application-specific integrated circuit die is disposed on the cover plate through glue dispensing and is located in the first isolation space, and the application-specific integrated circuit die is electrically connected to the power contact and the ground contact respectively through wire bonding technology

Step 709 : the MEMS die is disposed at the second through hole by dispensing, and the MEMS die is electrically connected to the power contact and the ground contact by wire bonding

Step 710 : the outer cover is covered on the cover plate and the isolation layer, the outer cover is electrically connected to the ground contact, and the outer cover is provided with openings relative to the MEMS die

Step 711: A closed chamber is formed by the substrate, the isolation layer, the outer cover and the MEMS die surrounded by the closed space, and the open space is formed by the substrate, the isolation layer, the outer cover and the MEMS die to form an open chamber

Step 801: A substrate is formed by combining the processes of bonding, opening, laminating, copper etching, solder masking and forming. The substrate is formed by stacking a bottom plate, a first side plate, a second side plate and a cover plate

Step 802: the first side plate is stacked on one end of the bottom plate, and the second side plate is stacked on the other end of the bottom plate

Step 803: The cover plate is stacked on the first side plate and the second side plate, an inner space is formed between the bottom plate, the first side plate, the second side plate and the cover plate, and the cover plate is interposed between the first side plate and the second side plate. A through hole and a second through hole, the inner space communicates with the outer space through the first through hole and the second through hole

Step 804: The bottom plate is embedded with a power supply circuit and a grounding circuit, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the bottom plate as a power supply external connection point and a grounding external connection point

Step 805: The first side plate is embedded with power lines and ground lines, and the second side plate is embedded with power lines and ground lines

Step 806: The cover plate is respectively embedded with a power supply circuit and a grounding circuit, the power supply circuit exposed on the top surface of the cover plate is a power supply contact, and the grounding circuit exposed on the top surface of the cover plate is a grounding contact

Step 807 : the application-specific integrated circuit die is disposed on the cover plate by means of glue dispensing, and the application-specific integrated circuit die is electrically connected to the power supply contact and the ground contact respectively through wire bonding technology

Step 808 : the MEMS die is disposed at the second through hole by dispensing, and the MEMS die is electrically connected to the power contact and the ground contact by wire bonding

Step 809: The isolation layer is stacked and attached to the MEMS die, and the isolation layer presents a hollow ring shape

Step 810: the outer cover is covered on the cover plate and the isolation layer, the outer cover and the isolation layer are attached to each other, the outer cover and the ground contact are electrically connected, and the outer cover is provided with an opening relative to the isolation layer

Step 811: A closed space is formed by the substrate, the isolation layer, the outer cover and the MEMS die to form a closed chamber, and the isolation layer is hollow and annular and has holes to form an open chamber

Step 901: A substrate with conductive grooves is formed by combining the processes of bonding, drilling, lamination, copper etching, solder masking, and molding. The substrate is embedded with power lines and ground lines, and the power lines and ground lines are exposed. The bottom surface of the base plate is the power supply connection point and the ground connection point.

Step 902 : the application-specific integrated circuit die is disposed on the substrate through glue dispensing, and the application-specific integrated circuit die is electrically connected to the power supply contact and the ground contact respectively through wire bonding technology

Step 903 : the MEMS die is disposed at the conductive groove by means of glue dispensing, and the MEMS die is electrically connected to the power contact and the ground contact by wire bonding technology

Step 904: The isolation layer is stacked and attached to the MEMS die, and the isolation layer presents a hollow ring shape

Step 905: the outer cover is covered on the substrate and the isolation layer, the outer cover and the isolation layer are attached to each other, the outer cover and the ground contact are electrically connected, and the outer cover is provided with an opening relative to the isolation layer

Step 906: The closed space is surrounded by the substrate, the isolation layer, the outer cover and the MEMS die to form a closed chamber, and the isolation layer has a hollow ring and openings to form an open chamber

FIG. 1 is a cross-sectional view of the first embodiment of the structure of the separated MEMS microphone according to the present invention.

FIG. 2 is a cross-sectional view of a second embodiment of the split MEMS microphone structure of the present invention.

FIG. 3 is a cross-sectional view of a third embodiment of the structure of the discrete MEMS microphone of the present invention.

FIG. 4A to FIG. 4I are schematic plan views of the conduction grooves of the separated MEMS microphone structure of the present invention.

Figure 5" shows the resonance diagram of the split MEMS microphone structure for this creation.

FIG. 6A and FIG. 6B are flow charts of the method of the first embodiment of the method for manufacturing the MEMS microphone structure according to the present invention.

FIG. 7A and FIG. 7B are flowcharts of a method of a second embodiment of the method for manufacturing the MEMS microphone structure of the present invention.

FIG. 8 is a flow chart of the method of the third embodiment of the manufacturing method of the MEMS microphone structure of the present invention.

The following will describe the implementation of the present creation in detail with the drawings and examples, so as to fully understand and implement the implementation process of how the present creation applies technical means to solve technical problems and achieve technical effects.

The following first describes the structure of the split-type MEMS microphone according to the first embodiment disclosed in the present invention, and please refer to "Fig. 1". A cross-sectional view of an embodiment.

The split MEMS microphone structure of the first embodiment disclosed in the present invention includes: a substrate 10 , an isolation layer 20 , an Application Specific Integrated Circuit (ASIC) 30 , a Micro Electro Mechanical System (Micro Electro Mechanical Systems, MEMS) The die 40 and the outer cover 50 and the substrate 10 further include: a bottom plate 11 , a first side plate 12 , a second side plate 13 and a cover plate 14 .

The substrate 10 is formed by bonding the bottom plate 11 , the first side plate 12 , the second side plate 13 and the cover plate 14 (including molecular bonding, anodic bonding, metal bonding, glass paste bonding, adhesive bonding, etc.), openings ( Including ceramic micro-opening, micro-laser opening, ultrasonic opening...etc.), lamination (including atomic layer deposition, chemical vapor deposition...etc.), copper etching (including isotropic chemical etching, non- Isotropic chemical etching, optical etching, etc.), solder mask and forming process are combined to make the bottom plate 11, the first side plate 12, the second side plate 13 and the cover plate 14 embedded with power lines and ground lines, power lines and ground The circuit exposed on the bottom surface of the bottom plate 11 is the power supply connection point 111 and the ground connection point 112 , and the power supply circuit and the ground circuit exposed on the top surface of the cover plate 14 are the power supply connection point 141 and the ground connection point 142 . The above process is only for illustration, and This does not limit the scope of application of this creation.

Specifically, the bottom plate 11 can be formed with a circuit space in the bottom plate 11 through stamping, photochemical reaction, and etching, and a power circuit and/or a ground circuit are deposited in the circuit space. After the side plate 12 is joined to the second side plate 13 at the other end, a continuous circuit space is formed in the first side plate 12 and the second side plate 13 through stamping, photochemical reaction, and etching, and a continuous circuit space is deposited in the continuous circuit space. The power circuit and/or the ground circuit are electrically connected with the power circuit and/or the ground circuit deposited in the circuit space of the bottom plate 11. The cover plate 14 is respectively joined to the first side plate 12 and the second side plate 13, and then Through stamping, photochemical reaction, and etching, a continuous circuit space is formed in the cover plate. The power circuit and/or the ground circuit are deposited in the continuous circuit space to form electrical connection with each other, that is, the bottom plate 11 , the first side plate 12 , the second side plate 13 and the cover plate 14 is embedded with a power circuit and a ground circuit to form the substrate 10, which is only for illustration, and does not limit the scope of application of the present invention.

It is worth noting that the first side plate 12 and the second side plate 13 can be two separate side plates, and the first side plate 12 and the second side plate 13 can also be an integral side plate, in the side plate through etching, openings... The first side plate 12 and the second side plate 13 are formed in cross-section by forming the through grooves in other manners. This is only an example, and does not limit the scope of application of the present invention.

An inner space 101 is formed between the bottom plate 11 , the first side plate 12 , the second side plate 13 and the cover plate 14 , and the cover plate 14 defines a first through hole 143 and a second through hole between the first side plate 12 and the second side plate 13 . Through the hole 144 (ie, through the opening method), the inner space 101 communicates with the outer space through the first through hole 143 and the second through hole 144 .

The isolation layer 20 is formed by stacking the first through holes 143 and the second through holes 144 on the substrate 10 (ie the cover plate 14 ). The space on one side of the isolation layer 20 is defined as the first isolation space 201 and the other side of the isolation layer 20 The space on the side is defined as the second isolation space 202 . The isolation layer 20 can be formed by deposition or by dispensing the isolation layer 20 on the cover plate 14 (ie, the substrate 10 ), which is only for illustration here. , and does not limit the scope of application of this creation.

The application-specific integrated circuit die 30 is disposed on the cover plate 14 (ie, the substrate 10 ) and located in the first isolation space 201 by means of dispensing, and the application-specific integrated circuit die 30 is electrically connected to the power contacts through wire bonding technology, respectively. 141 and the ground contact 142 , the MEMS die 40 is disposed at the second through hole 144 through glue dispensing, and the MEMS die 40 is electrically connected to the power contact 141 and the ground contact 142 by wire bonding technology.

The outer cover 50 covers the cover plate 14 (ie the substrate 10 ) and the isolation layer 20 , the outer cover 50 is electrically connected to the ground contact 142 , and the outer cover 50 is provided with an opening 51 relative to the MEMS die 40 , Generally speaking, the openings 51 formed on the outer cover 50 correspond to the positions of the MEMS die 40 , but the present invention is not limited thereto.

A closed chamber 61 is formed by the closed space surrounded by the substrate 10 , the isolation layer 20 , the outer cover 50 and the MEMS die 40 , and the open space is surrounded by the substrate 10 , the isolation layer 20 , the outer cover 50 and the MEMS die 40 An open chamber 62 is formed.

Next, the structure of the split MEMS microphone according to the second embodiment disclosed in the present invention will be described, and please refer to "Fig. 2". "Fig. 2" shows the second structure of the split MEMS microphone of the present invention. Cross-sectional view of the implementation.

The split MEMS microphone structure of the second embodiment disclosed in the present invention includes a substrate 10 , an isolation layer 20 , an application-specific integrated circuit die 30 , a MEMS die 40 and an outer cover 50 . The substrate 10 further It includes: a bottom plate 11 , a first side plate 12 , a second side plate 13 and a cover plate 14 .

The substrate 10 is formed by bonding the bottom plate 11 , the first side plate 12 , the second side plate 13 and the cover plate 14 (including molecular bonding, anodic bonding, metal bonding, glass paste bonding, adhesive bonding, etc.), openings ( Including ceramic micro-opening, micro-laser opening, ultrasonic opening...etc.), lamination (including atomic layer deposition, chemical vapor deposition...etc.), copper etching (including isotropic chemical etching, non- Isotropic chemical etching, optical etching, etc.), solder mask and forming process are combined to make the bottom plate 11, the first side plate 12, the second side plate 13 and the cover plate 14 embedded with power lines and ground lines, power lines and ground The circuit exposed on the bottom surface of the bottom plate 11 is the power supply connection point 111 and the ground connection point 112 , and the power supply circuit and the ground circuit exposed on the top surface of the cover plate 14 are the power supply connection point 141 and the ground connection point 142 . The above process is only for illustration, and This does not limit the scope of application of this creation.

It is worth noting that the first side plate 12 and the second side plate 13 may be two separate side plates, and the first side plate 12 and the second side plate 13 may also be an integral side plate. The through-grooves are formed by means of over-etching, opening, etc., so that the cross-section is presented as the first side plate 12 and the second side plate 13 , which is only for illustration, and does not limit the scope of application of the present invention.

Specifically, the bottom plate 11 can be formed with a circuit space in the bottom plate 11 through stamping, photochemical reaction, and etching, and a power circuit and/or a ground circuit are deposited in the circuit space. After the side plate 12 is joined to the second side plate 13 at the other end, a continuous circuit space is formed in the first side plate 12 and the second side plate 13 through stamping, photochemical reaction, and etching, and a continuous circuit space is deposited in the continuous circuit space. The power circuit and/or the ground circuit are electrically connected with the power circuit and/or the ground circuit deposited in the circuit space of the bottom plate 11. The cover plate 14 is respectively joined to the first side plate 12 and the second side plate 13, and then Through stamping, photochemical reaction, and etching, a continuous circuit space is formed in the cover plate. Power lines and/or ground lines are deposited in the continuous circuit space to form electrical connection with each other, that is, power lines and ground lines are embedded in the bottom plate 11 , the first side plate 12 , the second side plate 13 and the cover plate 14 to make the circuit. The formation of the substrate 10 is merely illustrative, and does not limit the scope of application of the present invention.

An inner space 101 is formed between the bottom plate 11 , the first side plate 12 , the second side plate 13 and the cover plate 14 , and the cover plate 14 defines a first through hole 143 and a second through hole between the first side plate 12 and the second side plate 13 . Through the hole 144 (ie, through the opening method), the inner space 101 communicates with the outer space through the first through hole 143 and the second through hole 144 .

The application-specific integrated circuit die 30 is disposed on the cover plate 14 (ie, the substrate 10 ) by means of dispensing, and the application-specific integrated circuit die 30 is electrically connected to the power supply contact 141 and the ground contact 142 respectively through wire bonding technology. The MEMS die 40 is disposed at the second through hole 144 through glue dispensing, and the MEMS die 40 is electrically connected to the power contact 141 and the ground contact 142 by wire bonding.

The isolation layer 20 can be formed by deposition method and etching method, or the isolation layer 20 can be stacked and attached to the MEMS die 40 by dispensing method. On the cover plate 14 (ie the substrate 10 ) and the isolation layer 20 , the outer cover 50 and the isolation layer 20 are attached to each other, the outer cover 50 is electrically connected to the ground contact 142 , and the outer cover 50 is opposite to the MEMS die 40 There are openings 51 there. Generally speaking, the openings 51 on the outer cover 50 correspond to the positions of the MEMS die 40 , but the present invention is not limited to this.

A closed cavity 61 is formed by a closed space surrounded by the substrate 10 , the isolation layer 20 , the outer cover 50 and the MEMS die 40 , and an open cavity 62 is formed by the hollow ring of the isolation layer 20 and the opening 51 .

Next, the structure of the separated MEMS microphone according to the third embodiment disclosed in the present invention will be described, and please refer to "Fig. 3", which shows the third embodiment of the separated MEMS microphone structure of the present invention. Cross-sectional view of the implementation.

The separated MEMS microphone structure of the third embodiment disclosed in the present invention includes a substrate 10 , an application-specific integrated circuit die 30 , a MEMS die 40 , an isolation layer 20 and an outer cover 50 .

The conductive grooves 15 can be formed on the substrate 10 by using a micro-laser method, an ultrasonic method, an etching method, etc. This is only an example, and does not limit the application scope of the present invention. Substrate bonding (including molecular bonding, anodic bonding, metal bonding, glass paste bonding, adhesive bonding, etc.), opening (including ceramic micro-holes, micro-laser holes, ultrasonic holes, etc.) , lamination (including atomic layer deposition, chemical vapor deposition, etc.), copper etching (including isotropic chemical etching, anisotropic chemical etching, optical etching, etc.), solder mask and forming process combination to The substrate 10 is embedded with a power supply circuit and a grounding circuit, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the substrate 10 as a power external connection point 102 and a grounding external connection point 103 , and the power supply circuit and the grounding circuit are exposed at the bottom surface. The top surface of the substrate 10 is the power contact 104 and the ground contact 105 . The above-mentioned process is only an example, and does not limit the scope of application of the present invention.

Specifically, the sub-substrate can be formed with a circuit space in the sub-substrate through stamping, photochemical reaction, and etching, and a power circuit and/or a grounding circuit are deposited in the circuit space, and another sub-substrate is bonded to the sub-substrate. After that, a continuous circuit space is formed in the sub-substrate through stamping, photochemical reaction, and etching, and a power circuit and/or a ground circuit is deposited in the continuous circuit space, and a power circuit is deposited in the circuit space. And/or the ground lines are electrically connected to each other, and so on, the power supply lines and the ground lines are embedded in the substrate 10 , which are only illustrative, and do not limit the scope of application of the present invention.

The application-specific integrated circuit die 30 is disposed on the substrate 10 by means of glue dispensing. The application-specific integrated circuit die 30 is electrically connected to the power supply contact 104 and the ground contact 105 through wire bonding technology, respectively. The MEMS die 40 The MEMS die 40 is electrically connected to the power contact 104 and the ground contact 105 by means of glue dispensing at the conductive groove 15 .

The isolation layer 20 can be formed by deposition method and etching method, or the isolation layer 20 can be stacked and attached to the MEMS die 40 by dispensing method. On the substrate 10 and the isolation layer 20 , the outer cover 50 and the isolation layer 20 are attached to each other, the outer cover 50 is electrically connected to the ground contact 142 , and the outer cover 50 is opened with an opening 51 relative to the MEMS die 40 . Generally speaking, the openings 51 formed on the outer cover 50 correspond to the positions of the MEMS die 40 , but the present invention is not limited thereto.

A closed cavity 61 is formed by a closed space surrounded by the substrate 10 , the isolation layer 20 , the outer cover 50 and the MEMS die 40 , and an open cavity 62 is formed by the hollow ring of the isolation layer 20 and the opening 51 .

Please refer to “FIG. 4A” to “FIG. 4I”, “FIG. 4A” to “FIG. 4I” are schematic plan views of the conduction grooves of the separated MEMS microphone structure of the present invention.

In "FIG. 4A" to "FIG. 4I", various aspects of the conduction groove 15 and the state in which the MEMS die 40 is disposed in the conduction groove 15 are respectively shown, in "FIG. 4A" to "FIG. 4I" The dotted line part in "" is the position where the MEMS die 40 is disposed in the conduction groove 15, and the various forms of the conduction groove 15 can be referred to as shown in "FIG. 4A" to "FIG. 4I".

Please refer to "Fig. 5". "Fig. 5" shows the resonance diagram of the split MEMS microphone structure of the present creation.

According to the Helmholtz resonance, the following formula is proposed:

Where, f _H = resonance frequency, v = speed of sound, V ₀ = static volume of the resonant cavity, L _eq = equivalent length of the bottle mouth, A = cross-sectional area of the opening, so it can be known that a smaller air volume will A higher resonance frequency is generated, and a larger air volume results in a lower resonance frequency, that is, the volume of the closed chamber 61 is related to the signal-to-noise ratio (SNR).

Therefore, the closed chamber 61 established in the present invention can increase the film moving ability in the MEMS die 40, that is, can improve the low frequency response. When the sound enters through the opening 51, due to the volume of the closed chamber 61 It will be larger than the volume of the resonant cavity, which can increase the resonance frequency and thus improve the sensitivity.

Next, the operation method of the first embodiment of the present creation will be described below, and please refer to "Fig. 6A" and "Fig. 6B", which are shown in "Fig. 6A" and "Fig. A method flow chart of a first embodiment of a method of manufacturing an electromechanical system microphone structure.

The manufacturing method of the split MEMS microphone structure of the first embodiment disclosed in the present invention includes the following steps:

First, a substrate is formed by combining the processes of bonding, drilling, lamination, copper etching, solder masking, and forming. The first side plate is stacked on one end of the bottom plate, and the second side plate is stacked on the other end of the bottom plate (step 702 ); then, the cover plate is stacked on the first side plate and the second side plate, the bottom plate, the first side plate, the second side plate and the An inner space is formed between the cover plates, the cover plate is provided with a first through hole and a second through hole between the first side plate and the second side plate, and the inner space communicates with the outer space through the first through hole and the second through hole (Step 703 ); Next, the power supply circuit and the grounding circuit are embedded in the bottom plate, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the bottom plate as the power external connection point and the ground external connection point (step 704 ); Then, the first side plate is embedded with a power supply circuit and the grounding circuit, and the second side plate is embedded with a power circuit and a grounding circuit (step 705); then, the cover plate is respectively embedded with a power circuit and a grounding circuit, and the power circuit exposed on the top surface of the cover is a power contact and a grounding circuit A ground contact is exposed on the top surface of the cover plate (step 706 ); then, an isolation layer is stacked on the substrate between the first through hole and the second through hole, and the space on one side of the isolation layer is defined as the first isolation space and defining the space on the other side of the isolation layer as the second isolation space (step 707 ); then, the application-specific integrated circuit die is disposed on the cover plate and located in the first isolation space by means of dispensing, and the application-specific integrated circuit is located in the first isolation space. The die is electrically connected to the power supply contact and the ground contact respectively through wire bonding technology (step 708 ); then, the MEMS die is disposed at the second through hole by means of dispensing, and the MEMS die is electrically connected to the second through hole through the wire bonding technology. connected to the power supply contact and the ground contact (step 709); then, the outer cover is covered on the cover plate and the isolation layer, the outer cover and the ground contact are electrically connected, and the outer cover is opened relative to the MEMS die There are openings (step 710); finally, a closed space is formed by the substrate, the isolation layer, the outer cover, and the MEMS die to form a closed chamber, and the open cavity is surrounded by the substrate, the isolation layer, the outer cover, and the MEMS die. The space forms an open chamber (step 711).

Next, the operation method of the second embodiment of the present creation will be described below, and please refer to "Fig. 7A" and "Fig. 7B". A method flow chart of a second embodiment of a method of manufacturing an electromechanical system microphone structure.

The manufacturing method of the split MEMS microphone structure of the second embodiment disclosed in the present invention includes the following steps:

First, a substrate is formed by combining the processes of bonding, drilling, lamination, copper etching, solder masking and forming. The substrate is formed by stacking a bottom plate, a first side plate, a second side plate and a cover plate (step 801); The first side plate is stacked on one end of the bottom plate, and the second side plate is stacked on the other end of the bottom plate (step 802 ); then, the cover plate is stacked on the first side plate and the second side plate, the bottom plate, the first side plate, the second side plate and the An inner space is formed between the cover plates, the cover plate is provided with a first through hole and a second through hole between the first side plate and the second side plate, and the inner space communicates with the outer space through the first through hole and the second through hole (step 803); then, the power supply circuit and the grounding circuit are embedded in the bottom plate, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the bottom plate as the power external connection point and the ground external connection point (step 804); then, the first side plate is embedded with a power supply circuit and the grounding circuit, and the second side plate is embedded with a power circuit and a grounding circuit (step 805); then, the cover plate is respectively embedded with a power circuit and a grounding circuit, and the power circuit exposed on the top surface of the cover is a power contact and a grounding circuit The exposed top surface of the cover plate is a ground contact (step 806 ); then, the application-specific integrated circuit chips are disposed on the cover plate by means of dispensing, and the application-specific integrated circuit chips are respectively electrically connected to the power supply through wire bonding technology. contact and ground contact (step 807 ); then, the MEMS die is disposed at the second through hole by means of dispensing, and the MEMS die is electrically connected to the power contact and the ground contact ( Step 808); then, the isolation layer is stacked and attached to the MEMS die, and the isolation layer presents a hollow ring (step 800); then, the outer cover is covered on the cover plate and the isolation layer, and the outer cover and the isolation layer are mutually Adhere to each other, the outer cover and the ground contact form an electrical connection Then, the outer cover is opened with an opening relative to the isolation layer (step 810); finally, a closed space is formed by the substrate, the isolation layer, the outer cover and the MEMS die to form a closed space, and the isolation layer is hollow and annular and open. The holes form open chambers (step 811).

Next, the operation method of the third embodiment of the present invention will be described below, and please refer to "Fig. 8". "Fig. 8" shows the third embodiment of the manufacturing method of the MEMS microphone structure of the present invention. Sample method flow chart.

The third embodiment disclosed in the present invention discloses a method for manufacturing a split-type MEMS microphone structure, which includes the following steps:

First, a substrate with conductive grooves is formed by combining the processes of bonding, drilling, lamination, copper etching, solder masking, and forming. The substrate is embedded with power lines and ground lines, and the power lines and ground lines are exposed to the substrate. The bottom surface is the power supply connection point and the ground connection point, and the power supply line and the ground connection line are exposed on the top surface of the substrate to be the power supply connection point and the ground connection point (step 901 ); then, the specific application integrated circuit die is disposed on the substrate by dispensing. , the specific application integrated circuit die is electrically connected to the power contact and the ground contact respectively through the wire bonding technology (step 902 ); then, the MEMS die is disposed at the conduction groove by dispensing glue, and the MEMS die is The power contacts and the ground contacts are electrically connected by wire bonding technology (step 903 ); then, the isolation layer is stacked and attached to the MEMS die, and the isolation layer presents a hollow ring (step 904 ); then, the outer cover is Covering the substrate and the isolation layer, the outer cover and the isolation layer are attached to each other, the outer cover and the ground contact are electrically connected, and the outer cover is provided with an opening relative to the isolation layer (step 905); finally, the substrate, The isolation layer, the outer cover, and the MEMS die surround the closed space to form a closed cavity, and the isolation layer has a hollow ring and an opening to form an open cavity (step 906 ).

To sum up, it can be seen that the difference between the present creation and the prior art lies in the combination of bonding, hole opening, film lamination, copper etching, solder masking and forming processes to form the substrate, the isolation layer is arranged on the substrate, and the specific application area is The bulk circuit die is arranged on the substrate by means of dispensing, and the MEMS die is arranged at the second through hole of the substrate by means of dispensing, and the enclosed space is surrounded by the substrate, the isolation layer, the outer cover and the MEMS die. Form a closed chamber.

This technical means can solve the problem that the flip-chip technology in the prior art cannot form the MEMS die into a closed cavity structure, thereby achieving the technical effect of providing the MEMS die to form a closed cavity structure.

Although the embodiments disclosed in this creation are as above, the content described is not used to directly limit the scope of patent protection of this creation. Anyone with ordinary knowledge in the technical field to which this creation belongs can make some changes in the form and details of the implementation without departing from the spirit and scope disclosed by this creation. The scope of patent protection for this creation is still subject to the scope of the appended patent application.

10: Substrate

11: Bottom plate

111: Power external point

112: Ground external point

12: The first side panel

13: Second side panel

14: Cover

141: Power contact

142: ground contact

143: first through hole

144: second through hole

20: isolation layer

201: First Isolation Space

202: Second Isolation Space

30: Application specific integrated circuit die

40: MEMS die

50: Outer cover

51: Opening

61: Close the chamber

62: Open Chamber

Claims (6)

An isolated MEMS microphone structure, comprising: a substrate, the substrate further comprises: a bottom plate, wherein the bottom plate is embedded with a power supply circuit and a grounding circuit, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the bottom plate as a power external connection point and a ground external connection point; a first side plate, the first side plate is stacked on one end of the bottom plate, and a power circuit and a ground circuit are embedded in the first side plate; a second side plate, the second side plate is stacked on the other end of the bottom plate, the second side plate is embedded with a power circuit and a ground circuit; and a cover plate, the cover plate is stacked on the first side plate and the second side plate, an inner space is formed between the bottom plate, the first side plate, the second side plate and the cover plate, The cover plate defines a first through hole and a second through hole between the first side plate and the second side plate, and the inner space is formed by the first through hole and the second through hole. The hole communicates with the external space, the cover plate is respectively embedded with a power supply circuit and a grounding circuit, and the power supply circuit and the grounding circuit are exposed on the top surface of the cover plate as a power supply contact and a grounding contact; An isolation layer is formed by stacking on the substrate between the first through hole and the second through hole, and a space on one side of the isolation layer is defined as a first isolation space and the isolation layer is The space on the other side is defined as a second isolation space; A specific application integrated circuit (Application Specific Integrated Circuit, ASIC) die, the specific application integrated circuit die is disposed on the cover plate and located in the first isolation space by means of dispensing. The integrated circuit die is electrically connected to the power supply contact and the ground contact respectively through the wire bonding technology; A Micro Electro Mechanical Systems (MEMS) die, the MEMS die is disposed at the second through hole through glue dispensing, and the MEMS die is electrically connected to the second through hole through wire bonding technology power contacts and ground contacts; and an outer cover, the outer cover covers the cover plate and the isolation layer, the outer cover is electrically connected with the ground contact, and the outer cover is opened with respect to the MEMS die opening, a closed cavity is formed by the substrate, the isolation layer, the outer cover and the MEMS die surrounded by a closed space, and the substrate, the isolation layer, the outer cover and the The MEMS die surrounds the open space to form an open cavity. The isolated MEMS microphone structure of claim 1, wherein the bottom plate, the first side plate, the second side plate, and the cover plate are made of holes, lamination, copper etching, solder masking, and forming. The manufacturing process is combined to form the substrate by stacking, and a power circuit and a ground circuit are embedded in the bottom plate, the first side plate, the second side plate and the cover plate. An isolated MEMS microphone structure, comprising: a substrate, the substrate further comprises: a bottom plate, wherein the bottom plate is embedded with a power supply circuit and a grounding circuit, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the bottom plate as a power external connection point and a ground external connection point; a first side plate, the first side plate is stacked on one end of the bottom plate, and a power circuit and a ground circuit are embedded in the first side plate; a second side plate, the second side plate is stacked on the other end of the bottom plate, the second side plate is embedded with a power circuit and a ground circuit; and a cover plate, the cover plate is stacked on the first side plate and the second side plate, an inner space is formed between the bottom plate, the first side plate, the second side plate and the cover plate, The cover plate defines a first through hole and a second through hole between the first side plate and the second side plate, and the inner space is formed by the first through hole and the second through hole. The hole communicates with the external space, the cover plate is respectively embedded with a power supply circuit and a grounding circuit, and the power supply circuit and the grounding circuit are exposed on the top surface of the cover plate as a power supply contact and a grounding contact; A specific application integrated circuit die, the specific application integrated circuit die is disposed on the cover plate through glue dispensing, and the specific application integrated circuit die is electrically connected to the power contacts through wire bonding technology respectively and ground contacts; a MEMS die, the MEMS die is disposed at the second through hole by means of dispensing, and the MEMS die is electrically connected to the power supply contact and the ground contact through a wire bonding technique; an isolation layer, the isolation layer is stacked and attached to the MEMS die, and the isolation layer presents a hollow ring; and an outer cover, the outer cover covers the cover plate and the isolation layer, the outer cover and the isolation layer are attached to each other, the outer cover is electrically connected with the ground contact, the The outer cover is provided with an opening relative to the isolation layer, and a closed cavity is formed by the closed space surrounded by the substrate, the isolation layer, the outer cover and the MEMS die, and the isolation layer The hollow ring and the opening form an open chamber. The isolated MEMS microphone structure of claim 3, wherein the bottom plate, the first side plate, the second side plate and the cover plate are made of holes, lamination, copper etching, solder masking and forming. The manufacturing process is combined to form the substrate by stacking, and a power circuit and a ground circuit are embedded in the bottom plate, the first side plate, the second side plate and the cover plate. An isolated MEMS microphone structure, comprising: A substrate, the substrate is provided with a conduction groove, the substrate is embedded with a power supply circuit and a grounding circuit, and the power supply circuit and the grounding circuit are exposed on the bottom surface of the substrate as a power external connection point and a grounding external connection point, and the power supply circuit and the grounding circuit are exposed. On the top surface of the substrate are power contacts and ground contacts; A specific application integrated circuit die, the specific application integrated circuit die is disposed on the substrate through a glue dispensing method, and the specific application integrated circuit die is electrically connected to the power contacts and the power supply contacts respectively through wire bonding technology ground contact; a MEMS die, the MEMS die is disposed at the conduction groove by means of dispensing, and the MEMS die is electrically connected to the power contact and the ground contact by wire bonding; an isolation layer, the isolation layer is stacked and attached to the MEMS die, and the isolation layer presents a hollow ring; and an outer cover, the outer cover covers the substrate and the isolation layer, the outer cover and the isolation layer are adhered to each other, the outer cover is electrically connected with the ground contact, the outer cover The cover is provided with an opening relative to the isolation layer, and a closed cavity is formed by the closed space surrounded by the substrate, the isolation layer, the outer cover and the MEMS die, and the isolation layer is hollow. The ring and the opening form an open chamber. The isolated MEMS microphone structure of claim 1, wherein the substrate is made by a combination of processes of opening, laminating, copper etching, solder masking and forming, and the substrate is embedded with power lines and ground line.

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