MEMS microphone

Abstract

According to the present embodiment, a MEMS microphone comprises: a first substrate; a second substrate stacked on the first substrate; a housing coupled to the first substrate to form an accommodation space therein; a MEMS structure disposed on the second substrate in the accommodation space; and a signal processing element spaced apart from the MEMS structure and disposed on the second substrate in the accommodation space, wherein the second substrate includes a plurality of bridges protruding from a side surface thereof.

Description

MEMS microphone

[0001] The present invention relates to a MEMS microphone.

[0002] Generally, audio devices generate sound by vibrating a diaphragm using electrodes, and significant advancements are being made in the field of audio equipment alongside recent technological developments. The applications of these devices are becoming increasingly diverse, such as in portable terminals and hearing aids, and as the devices in which they are applied become slimmer, the size of the audio devices themselves is also being miniaturized.

[0003] In addition, microphones utilizing MEMS (Micro Electro Mechanical Systems), a semiconductor technology, have recently been developed and are in use. MEMS is a technology that enables the manufacturing of small mechanical components. These MEMS microphones can be classified into electrostatic and piezoelectric types, and include the general capacitor type.

[0004] Recently, mobile communication terminals such as mobile phones and smartphones, as well as electronic devices like tablet PCs and MP3 players, are becoming smaller. Consequently, the components of these electronic devices are also becoming more miniaturized. Therefore, Micro Electro Mechanical System (MEMS) technology is required to overcome the physical limitations of these components.

[0005] The technical problem that the present invention aims to solve is to provide a MEMS microphone.

[0006] To solve the above technical problem, the MEMS microphone according to the present embodiment includes: a first substrate; a second substrate laminated on the first substrate; a housing coupled to the first substrate to form an internal receiving space; a MEMS structure disposed on the second substrate in the receiving space; and a signal processing element disposed on the second substrate in the receiving space, spaced apart from the MEMS structure, and the second substrate includes a plurality of bridges protruding from the side.

[0007] The second substrate includes a first side, a second side opposite to the first side, a third side connecting the first side and the second side, and a fourth side opposite to the third side, wherein the length of the first side in the longitudinal direction is greater than the length of the third side in the longitudinal direction, and the number of bridges formed on the first side may be greater than the number of bridges formed on the third side.

[0008] The second substrate includes a first side, a second side opposite to the first side, a third side connecting the first side and the second side, and a fourth side opposite to the third side, and the longitudinal length of the bridge formed on the first side may be 1 / 20 to 1 / 15 of the longitudinal length of the first side.

[0009] The length of the above bridge in the longitudinal direction may be 0.1 mm to 0.3 mm.

[0010] An adhesive layer may be disposed between the first substrate and the second substrate.

[0011] The first substrate includes one of a 2Metal COF substrate, an FPCB, and a PI-based COF substrate, and the second substrate may include a substrate made of metal material.

[0012] To solve the above technical problem, the MEMS microphone array according to the present embodiment includes: a first substrate array comprising a plurality of first substrate regions spaced apart from each other; a second substrate array stacked on the first substrate array; a plurality of housings each coupled to the plurality of second substrate regions of the second substrate array to form an internal receiving space; and a plurality of MEMS structures each disposed in the receiving space of the plurality of housings, wherein the second substrate array includes a plurality of second substrate regions corresponding to the plurality of first substrate regions and a plurality of bridges connecting the plurality of second substrate regions to each other.

[0013] Each of the plurality of second substrate regions includes a first side, a second side opposite to the first side, a third side connecting the first side and the second side, and a fourth side opposite to the third side, and the length of the first side in the longitudinal direction is greater than the length of the third side in the longitudinal direction, and the number of bridges formed on the first side may be greater than the number of bridges formed on the third side.

[0014] Each of the plurality of second substrate regions includes a first side, a second side opposite to the first side, a third side connecting the first side and the second side, and a fourth side opposite to the third side, and the longitudinal length of the bridge formed on the first side may be 1 / 20 to 1 / 15 of the longitudinal length of the first side.

[0015] The first substrate array includes one of a 2Metal COF substrate, an FPCB, and a PI-based COF substrate, and the second substrate array may include a substrate made of metal material.

[0016] According to the embodiments, quality can be improved by applying a bridge structure to the substrate to prevent distortion of the substrate caused by differences in shrinkage rates due to the thermal process.

[0017] In addition, while the edges of the substrate unit were all cut in the existing structure, in this embodiment, only the bridge section of the substrate is cut, thereby shortening the cutting process time and increasing production efficiency.

[0018] In addition, quality can be improved by reducing the area and ratio of substrate burrs occurring at the cut surface.

[0019] FIG. 1 is a side view illustrating the structure of a MEMS microphone according to the present embodiment.

[0020] FIG. 2 is an exploded view of a substrate unit of a MEMS microphone according to the present embodiment.

[0021] FIG. 3 is a diagram illustrating the manufacturing process of a substrate unit of a MEMS microphone according to the present embodiment.

[0022] FIG. 4 is a side view illustrating a substrate unit of a MEMS microphone according to the present embodiment.

[0023] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0024] However, the technical concept of the present invention is not limited to some of the described embodiments but can be implemented in various different forms, and within the scope of the technical concept of the present invention, one or more of the components among the embodiments may be selectively combined or substituted.

[0025] In addition, terms used in this embodiment (including technical and scientific terms) may be interpreted in a sense that is generally understood by those skilled in the art to which this embodiment belongs, unless explicitly and specifically defined otherwise. Terms that are commonly used, such as terms defined in advance, may be interpreted in consideration of their meaning in the context of the relevant technology.

[0026] Furthermore, the terms used in this embodiment are for the purpose of describing the embodiment and are not intended to limit the invention.

[0027] In this specification, the singular form may include the plural form unless specifically stated otherwise in the text, and when described as "at least one of A and B and C (or more than one)," it may include one or more of all combinations that can be formed from A, B, and C.

[0028] In addition, terms such as first, second, A, B, (a), (b), etc., may be used when describing the components of the present embodiment. These terms are used merely to distinguish the components from other components and are not intended to limit the essence, order, or sequence of the components.

[0029] And, where it is stated that a component is 'connected', 'combined', or 'connected' to another component, this may include not only cases where the component is directly 'connected', 'combined', or 'connected' to the other component, but also cases where it is 'connected', 'combined', or 'connected' due to another component located between the component and the other component.

[0030] Furthermore, when described as being formed or placed "above" or "below" each component, "above" or "below" includes not only cases where two components are in direct contact with each other, but also cases where one or more other components are formed or placed between the two components. Additionally, when expressed as "above" or "below," it may include the meaning of a downward direction as well as an upward direction relative to a single component.

[0031]

[0032] FIG. 1 is a side view illustrating the structure of a MEMS microphone according to the present embodiment, FIG. 2 is an exploded view of a substrate unit of a MEMS microphone according to the present embodiment, FIG. 3 is a drawing for explaining the manufacturing process of a substrate unit of a MEMS microphone according to the present embodiment, and FIG. 4 is a side view for explaining a substrate unit of a MEMS microphone according to the present embodiment.

[0033] Referring to FIG. 1, the MEMS microphone according to the present embodiment may include a first substrate (100), a second substrate (200), a MEMS structure (300), a housing (400), a signal processing element (500), and at least one capacitor (600).

[0034] The first substrate (100) is placed at the bottom of the MEMS microphone, has a plate shape, and can be electrically connected to the outside. The second substrate (200) is placed on the upper part of the first substrate (100), so that the first substrate (100) and the second substrate (200) can form a single substrate unit, and the substrate unit can form an internal space together with the housing (400).

[0035] The first substrate (100) is a flexible substrate and may be a Chip on Film (COF) substrate or a flexible printed circuit board (FPCB). A Chip on Film (COF) substrate is a substrate formed by forming a circuit on a base film or mounting a component such as a chip, and has a film shape, so it is a substrate with a thickness that is considerably thinner than other substrates. By using a COF substrate as the substrate for a MEMS microphone, the thickness can be reduced compared to the case where a conventional rigid substrate is used.

[0036] The first substrate (100) is a COF substrate and may include a 2-metal COF substrate. The 2-metal COF may be formed in a structure in which a metal layer is laminated on the upper and lower surfaces of a base film so as to form a circuit or mount a device on both sides of a base film.

[0037] A flexible printed circuit board (FPCB) is a flexible circuit board that is also flexible and has a thinner thickness compared to a standard PCB board, so the thickness can be reduced by using a flexible printed circuit board as a substrate for a MEMS microphone. Other types of flexible substrates may be included. For example, the first substrate (100) may be an LCP (Liquid Crystal Polymer)-based FPCB, a PI (Polyimide)-based FPCB, or a PI-based COF, and the type of the first substrate (100) is not limited to the examples described above.

[0038] A hole may be formed in the first substrate (100) at a position facing the lower part of the MEMS structure (300). The cross-sectional area of ​​the hole may be circular, but is not limited thereto. Here, the hole may be an acoustic hole.

[0039] The first substrate (100) may include a first pad (110). The first substrate (100) may have a first front pad formed on its front surface to be electrically connected to a second pad of the second substrate (200) and a first rear pad formed to be electrically connected to a rear external configuration. That is, the first pad (110) may include a first front pad and a first rear pad.

[0040] A plurality of first front pads and a first connection circuit connecting them may be formed on the front surface of the first substrate (100). A signal processing element and a capacitor may be electrically connected to the plurality of first front pads and the first connection circuit. A plurality of first rear pads and a second connection circuit may be formed on the rear surface of the first substrate (100).

[0041] The first substrate (100) may include via holes. In this case, the first substrate (100) may connect the first front pad and the first rear pad formed on both sides through a metal layer (e.g., via) formed in the via holes. Some of the first pads (110) may be exposed through the cavity (210) of the second substrate (200).

[0042]

[0043] The second substrate (200) is a substrate having a plate shape that is stacked to be placed on top of the first substrate (100). The second substrate (200) may include a rigid substrate, and may include, for example, a printed circuit board (PCB), a semiconductor substrate, or a ceramic substrate, a metal plate, etc. The second substrate (200) may be composed of a single layer or may be formed by stacking a plurality of substrates.

[0044] The second substrate (200) may include via holes. In this case, the second substrate (200) may connect circuits or components formed on both sides through a metal layer (e.g., via) formed in the via holes. Here, the via holes may be micro via holes and may be configured with a size of 25 μm or less.

[0045] The second substrate (200) may include an acoustic hole. The cross-sectional area of ​​the acoustic hole may be circular, but is not limited thereto. The hole formed in the second substrate (200) may be arranged to communicate with the hole formed in the first substrate (100), and a MEMS structure (300) may be arranged on the upper part of the hole communicating with the first substrate (100) and the second substrate (200).

[0046] The second substrate (200) can be electrically connected to the first substrate (100). The second substrate (200) may include a plurality of pads for electrically connecting to the first substrate (100).

[0047] The second substrate (200) may include a second pad. The second pad may include a plurality of second front pads formed on the front surface of the second substrate (200) and a plurality of second rear pads formed on the rear surface of the second substrate (200). That is, the second pad may include a second front pad and a second rear pad. The second front pad may be electrically connected to a signal processing element (500) and a capacitor (600), and the second rear pad may be electrically connected to the first front pad of the first substrate (100). The second rear pad of the second substrate (200) may be formed to have the same or similar shape and size as the first front pad of the first substrate (100), and may be electrically connected by being stacked so that at least a portion overlaps vertically.

[0048] The second substrate (200) may include one or more cavities (210). The second substrate (200) is placed on top of the first substrate (100), and the first substrate (100) may be exposed to the top of the second substrate (200) through the cavity (210) of the second substrate (200). The first substrate (100) may be exposed to the top of the second substrate (200) by having a first pad (110), etc., placed in the space where the cavity (210) of the second substrate (200) is formed. In this case, since the upper surface of the first substrate (100) is placed on the lower surface of the second substrate (200), the first front pad (110), etc. formed on the upper surface of the first substrate (100) may be exposed to the top of the second substrate (200) through the cavity (210) of the second substrate (200). The first pad (110) of the first substrate (100) can be electrically connected to a signal processing element (500) and a capacitor (600) through a cavity (210) formed in the second substrate (200).

[0049] The second substrate (200) can be electrically connected to the signal processing element (500) and the capacitor (600). The second substrate (200) may include a plurality of pads, a plurality of connection circuits, and a plurality of vias for electrically connecting to the signal processing element (500) and the capacitor (600). The plurality of pads may overlap and contact the vias perpendicularly, or may contact an external substrate or element. The connection circuits may connect the second pads disposed on the same layer. The vias may be formed in via holes penetrating a base film or an insulating layer.

[0050] The second substrate (200) is laminated on top of the first substrate (100) so that the first substrate (100) and the second substrate (200) can form a single substrate unit. An adhesive layer (700) is disposed between the lower part of the second substrate (200) and the upper part of the first substrate (100) to bond the first substrate (100) and the second substrate (200). The adhesive layer (700) may have a shape and size corresponding to the shape and size of the first substrate (100) or the second substrate (200) as a means of bonding the first substrate (100) and the second substrate (200). The adhesive layer (700) may be made of a conductive material, but is not limited thereto and may be made of a non-conductive material.

[0051] A PSR (Photo Solder Resist) (800) may be placed on the upper surface of the second substrate (200). The PSR (800) is an ink used to protect and form circuits on the substrate. It is applied to the surface of the substrate and, after the circuits are formed, protects unnecessary parts to prevent corrosion or short circuits.

[0052] As the first substrate (100) and the second substrate (200) form a substrate unit, the second substrate (200) not only complements the rigidity of the first substrate (100) but also simplifies the pad design structure of the second substrate (200), and since the first substrate (100) is a flexible substrate that enables fine pitch, it is implemented to have a thinner thickness and increased fine pitch realization compared to a substrate unit using a rigid substrate where the existing pad design is performed, thereby having the effect of high freedom in circuit design.

[0053]

[0054] In the substrate unit manufacturing process for bonding the first substrate (100) and the second substrate (200), a heat process is performed in the Hot Press process for bonding the first substrate (100) and the second substrate (200), hot water washing for removing foreign matter, curing process after applying PSR (800) ink, plating process, etc., and subsequently, in the semiconductor component packaging process, additional heat processes are performed in the Baking, silicon or epoxy Curing, Solder Reflow, etc. processes.

[0055] A substrate unit manufactured by bonding a first substrate (100) with a thickness of about 50 µm, a second substrate (200) with a thickness of about 100 µm, and an adhesive layer (700) with a thickness of about 40 µm undergoes a thermal process, and a problem arises in which the substrate becomes warped due to the shrinkage rates of different raw materials. This embodiment is intended to solve this problem, and the warping of the substrate unit can be minimized by forming the shape of the second substrate (200) into a bridge structure.

[0056] The second substrate (200) of the MEMS microphone according to the present embodiment may include a plurality of bridges (201). The plurality of bridges (201) may protrude from the side of the second substrate (200).

[0057] The second substrate (200) may include a first side, a second side opposite the first side, a third side connecting the first side and the second side, and a fourth side opposite the third side. In the following description, the description of the first side may be replaced with the second side, and the description of the third side may be replaced with the fourth side. The length of the first side in the longitudinal direction and the length of the second side in the longitudinal direction are the same, and the length of the third side in the longitudinal direction and the length of the fourth side in the longitudinal direction may be the same.

[0058] The length of the first side in the longitudinal direction may be greater than the length of the third side in the longitudinal direction. In this case, the number of bridges (201) formed on the first side may be greater than the number of bridges (201) formed on the third side. For example, the number of bridges (201) formed on the first side may be 2, and the number of bridges (201) formed on the third side may be 1.

[0059] One longitudinal length (A in FIG. 4) of a bridge (201) formed on one side of the second substrate (200) may be formed to be 1 / 20 to 1 / 15 of the longitudinal length of one side. Here, the longitudinal length of the bridge (201) may refer to a length formed along a direction parallel to the side of the second substrate (200) to which the bridge (201) is connected.

[0060] If the length of the bridge (201) in the longitudinal direction satisfies the above condition, the distortion of the substrate unit during the thermal process in the MEMS microphone manufacturing process can be minimized. If the length of the bridge (201) in the longitudinal direction is less than the lower limit of the above condition, the effect of improving the distortion of the substrate unit may be minimal. If the length of the bridge (201) in the longitudinal direction exceeds the upper limit of the above condition, there is a problem that the cutting process time of the bridge (201) section increases.

[0061] For example, the longitudinal length of the bridge (201) may be 0.1 mm to 0.3 mm. The limitation on the numerical value is exemplary and is not specifically limited thereto.

[0062] When the bridge (201) structure of the second substrate (200) is not applied, the diagonal shrinkage is about 0.73%, and the vertical shrinkage (y-axis direction) is about 0.74%. On the other hand, when the bridge (201) structure of the second substrate (200) is applied, the diagonal shrinkage is about 0.54%, and the vertical shrinkage (y-axis direction) is about 0.54%.

[0063]

[0064] A MEMS microphone array according to the present embodiment may include a first substrate array, a second substrate array, a plurality of housings, and a plurality of MEMS structures. Specifically, the first substrate array may include a plurality of first substrate regions spaced apart from each other. A first substrate region may refer to a region included in an individual MEMS microphone. A plurality of first substrate regions may be arranged in an MXN configuration (M and N are natural numbers). When one first substrate region is individually bonded to one second substrate region, the first substrate array may include a plurality of first substrate regions connected to each other.

[0065] A second substrate array may be laminated on a first substrate array. An adhesive layer may be disposed between the first substrate array and the second substrate array. The second substrate array may include a plurality of second substrate regions corresponding to a plurality of first substrate regions, and a plurality of bridges connecting the plurality of second substrate regions to each other. The plurality of second substrate regions may be arranged so that the plurality of first substrate regions overlap with each other in the z-axis direction. Below, the description of the second substrate region is omitted as it overlaps with the description of the second substrate of the MEMS microphone individual unit, and the description of the plurality of bridges is omitted as it overlaps with the description of the bridge of the MEMS microphone individual unit.

[0066] A plurality of housings forming an internal receiving space may be included on a plurality of second substrate regions. A plurality of MEMS structures may be disposed in the receiving spaces of the plurality of housings. In addition, the description of the configuration disposed in the receiving spaces of the housings is omitted as it overlaps with the description of the structure of individual MEMS microphones.

[0067] Referring to FIG. 3, in the substrate fabrication process of a MEMS microphone, the second substrate (200) is fabricated in an array form, and then the bridge (201) is cut in a sawing process to be fabricated into individual MEMS microphones. After the packaging process is performed in the form of a MEMS microphone array, a fabrication process of cutting into individual MEMS microphones can be performed.

[0068] In the process of cutting the MEMS microphone array into individual MEMS microphones, the entire edge of the second substrate (200) had to be blade-sawed or laser-sawed in the past, but according to the present embodiment, only the bridge structure needs to be cut, so the manufacturing process can be simplified.

[0069] If the entire edge of the second substrate (200) is cut, there is a problem in that burrs are generated in the first substrate (100) and the adhesive layer (700) due to heat generated during the cutting process, but in the second substrate array according to the present embodiment, only the bridge structure needs to be cut, so the generation of burrs can be reduced.

[0070] In addition, by reducing the size of the bridge of the second substrate array according to the present embodiment to an appropriate size, the maximum number of second substrate regions can be formed in the second substrate array having the same area. Through this, costs can be reduced by increasing the number of MEMS microphone units that can be produced per metal plate panel.

[0071] In addition, during the manufacturing process of the MEMS microphone, a second substrate array formed as a single undivided plate causes substrate distortion over a large area, whereas a second substrate array having a second substrate region divided by a bridge structure according to the present embodiment causes substrate distortion over a relatively small area, thus having the effect of improving the distortion of the MEMS microphone.

[0072] FIG. 4(a) is a side view of a substrate unit of a MEMS microphone, and FIG. 4(b) is a side view of the substrate unit of a MEMS microphone according to the present embodiment, cut along the CC line of FIG. 3. Referring to FIG. 4(a), the bridge structure cannot be seen in the side view of the substrate unit of a MEMS microphone without the application of a bridge structure.

[0073] Referring to the X region of FIG. 4(b), a first substrate (100), an adhesive layer (700), and a PSR (800) layer are arranged in sequence, and a bridge (201) placed on the first substrate (100) can be seen. If the adhesive layer (700) or the PSR (800) layer is partially melted by a thermal process during the manufacturing process of the MEMS microphone, the bridge (201) can be placed between the adhesive layers (700) or between the PSR (800) layers as shown in FIG. 4(b).

[0074]

[0075] A housing (400), a MEMS structure (300), a signal processing element (500), and a capacitor (600) may be disposed on the second substrate (200). The capacitor (600) may be optionally disposed on the second substrate (200) as needed.

[0076] A housing (400) is a means for being placed on top of a second substrate (200) and forming a receiving space inside. The housing (400) may be formed in the shape of a cover with an open bottom surface, and the receiving space may be formed by the bottom surface of the housing (400) being joined to the top surface of the second substrate (200). The housing (400) and the second substrate (200) may be joined by solder being placed on top of the second substrate (200) and adhering to the bottom surface of the housing (400). Noise conditions such as SNR (Signal-to-Noise Ratio), PSR (Power Supply Rejection), and PSRR (Power Supply Rejection Ratio) may be determined according to the size (Back Volume) of the receiving space formed inside the housing (400).

[0077] The housing (400) may be made of nickel silver or stainless steel (SUS). Nickel silver is a material containing 15-30% zinc and 10-20% nickel in copper, and allows for solder bonding without plating in its raw material state. Applying plating to the seating area of ​​the housing (400) can improve the solder bond adhesion. Ni+Au plating can be applied. Both electroless and electrolytic plating processes can be applied. Although stainless steel (SUS) contains Ni, the solder bond adhesion may decrease if plating is not performed. Therefore, plating can be applied. Unlike nickel silver, the plating adhesion on the surface of stainless steel may decrease when electroless plating is applied, so plating can be performed using an electrolytic plating process.

[0078] The MEMS structure (300) may be placed within a receiving space formed by a housing (400). The MEMS structure (300) may include a body (310), a backplate (330), and a diaphragm (320). The MEMS structure (300) may be placed on top of a second substrate (200), and the lower part of the MEMS structure (300) may be placed at a position adjacent to an acoustic hole (10) of the second substrate (200).

[0079] The body (310) is a means for forming a partition wall that surrounds the acoustic hole (10) formed in the second substrate (200). The body (310) can be coupled to the second substrate (200) so as to be electrically connected to the first substrate (100) through the second substrate (200). Additionally, an acoustic hole (360) communicating with the acoustic hole (10) can be formed in the body (310). The body (310) can be electrically connected to the second substrate (200).

[0080] An acoustic hole (360) may be formed in the body (310). When the body (310) is coupled to the second substrate (200), the acoustic hole (10) formed in the first substrate (100) and the second substrate (200) and the acoustic hole (360) of the body (310) may be arranged to communicate with each other, and thus, sound from the outside may be designed to flow in through the acoustic hole (10).

[0081] The backplate (330) and the diaphragm (320) can be placed in the acoustic hole (10) formed in the body (310). The diaphragm (320) can vibrate due to the sound pressure of the sound when sound is introduced from the outside through the acoustic hole (10), and the backplate (330) can sense the acoustic signal by measuring the capacitance according to the vibration of the diaphragm (320). Although the backplate is shown as being located above the diaphragm (320) in the drawing, the diaphragm (320) may also be located above the backplate.

[0082] One or more body pads for electrical connection may be formed on the upper surface of the body (310). The body pads may be electrically connected to the backplate (330) and the diaphragm (320), and may be electrically connected to the signal processing element (500), which will be described later, via a wire. However, the connection method is merely an example, and as needed, the body pads may be placed in a form directly mounted on the pads of the second substrate (200) and electrically connected to the signal processing element (500) through a connection circuit. As the shape and material of the body pads are known technologies for electrical connection, a description thereof is omitted.

[0083] The signal processing element (500) is electrically connected to the MEMS structure (300) and can process electrical signals sensed from the MEMS structure (300). The MEMS structure (300) and the signal processing element (500) can be electrically connected through a body pad. For example, the MEMS structure (300) and the signal processing element (500) can be connected by a wire through wire bonding. As another example, the MEMS structure (300) and the signal processing element (500) can be electrically connected through a connection circuit of the second substrate (200) while mounted on the second substrate (200) in a flip-chip form. When the MEMS structure (300) and the signal processing element (500) are wire-bonded, a signal pad may be placed on the signal processing element (500) to be connected to the body pad of the MEMS structure (300) through wire bonding.

[0084] The signal processing element (500) can amplify a signal sensed from the MEMS structure (300). Here, the signal processing element (500) may include an Application-Specific Integrated Circuit (ASIC), but is not limited thereto. The signal processing element (500) may be formed as a single module or may be formed in the form of a chip. The signal processing element (500) may include an ASIC and an En-cap that coats the ASIC.

[0085] A signal processing element (500) may be placed on a second substrate (200). The signal processing element (500) may be electrically connected to a first substrate (100) through the second substrate (200). The signal processing element (500) may be placed on the second substrate (200) spaced apart from the MEMS structure (300). The signal processing element (500) may be placed in a receiving space formed inside a housing (400) spaced apart from the MEMS structure (300) and may receive a signal from the MEMS structure (300). Since signal transmission between the MEMS structure (300) and the signal processing element (500) takes place in the receiving space formed by the housing (400), external interference is reduced, and thereby noise can be reduced.

[0086] The signal processing element (500) can be electrically connected to the MEMS structure (300) and the first substrate (100). The signal processing element (500) can be electrically connected to the MEMS structure (300). The signal processing element (500) can be electrically connected to a body pad formed on the body (310) of the MEMS structure (300) by having a signal pad disposed on its upper surface. The signal pad of the signal processing element (500) and the body pad of the MEMS structure (300) can be electrically connected through wire bonding, thereby allowing the signal processing element (500) and the MEMS structure (300) to be electrically connected.

[0087] The signal processing element (500) can be electrically connected to the first substrate (100) by being electrically connected to the second substrate (200). The signal processing element (500) can be electrically connected to the second substrate (200) through wire bonding or electrically connected by being mounted on the second substrate (200) in the form of a flip chip. Since a plurality of pads are arranged on the second substrate (200), the signal processing element (500) can be electrically connected to the pads of the second substrate (200) through wire bonding or electrically connected by being mounted on the pads of the second substrate (200) in the form of a flip chip, and can be electrically connected to the first substrate (100) through the pads of the second substrate (200). The signal processed by the signal processing element (500) can be transmitted to an external location requiring the signal through one or more of the pads, connection circuits, and vias formed on the second substrate (200) and through the pads formed on the first substrate (100).

[0088] A capacitor (600) may be optionally placed on the upper part of the second substrate (200) as needed. When the capacitor (600) is placed, the performance of PSRR (Power Supply Rejection Ratio), which is RF-related noise, and PSR (Power Supply Rejection), which is power-related noise, may be improved. That is, through the capacitor (600), noise-related performance such as SNR (Signal-to-Noise Ratio), PSR (Power Supply Rejection), and PSRR (Power Supply Rejection Ratio) can be improved. The capacitor (600) may be electrically connected to the signal processing element (500). As a result, the capacitor (600) can remove noise during the signal processing process in the signal processing element (500).

[0089] The capacitor (600) is positioned on the upper part of the second substrate (200) and can be electrically connected to the signal processing element (500) and can be electrically connected to the first substrate (100) through the second substrate (200). The capacitor (600) can be electrically connected to the signal processing element (500) and the first substrate (100) via wires. The capacitor (600) can be electrically connected to the signal pad of the signal processing element (500) via wire bonding and can be electrically connected to the pad of the second substrate (200) via wire bonding.

[0090] However, the capacitor (600) can be electrically connected to the first substrate (100) not only by bonding via wires but also by mounting it on the second substrate (200) or the signal processing element (500) in a flip-chip form. For example, the capacitor (600) can be mounted on a second pad formed on the upper part of the second substrate (200). The capacitor (600) can be mounted on a second front pad formed on the front surface of the second substrate (200). As the fine-pitch circuit implementation of the second substrate (200) becomes possible, the effect of securing mounting space for the capacitor is achieved.

[0091] Those skilled in the art related to the embodiments described above will understand that they may be implemented in modified forms without departing from the essential characteristics of the description. Therefore, the disclosed methods should be considered in an illustrative rather than a restrictive sense. The scope of the invention is defined by the claims, not by the foregoing description, and all variations within the scope of equivalence should be interpreted as being included in the invention.

Claims

1. First substrate; A second substrate laminated on the first substrate; A housing coupled to the first substrate and forming an internal receiving space; A MEMS structure disposed on the second substrate in the above receiving space; It includes a signal processing element spaced apart from the MEMS structure and disposed on the second substrate in the receiving space, and The above-mentioned second substrate is a MEMS microphone comprising a plurality of bridges protruding from the side.

2. In Paragraph 1, The second substrate includes a first side, a second side opposite to the first side, a third side connecting the first side and the second side, and a fourth side opposite to the third side. The length of the first side in the longitudinal direction is greater than the length of the third side in the longitudinal direction, and A MEMS microphone in which the number of bridges formed on the first side is greater than the number of bridges formed on the third side.

3. In Paragraph 1, The second substrate includes a first side, a second side opposite to the first side, a third side connecting the first side and the second side, and a fourth side opposite to the third side. A MEMS microphone in which the longitudinal length of the bridge formed on the first side is 1 / 20 to 1 / 15 of the longitudinal length of the first side.

4. In Paragraph 1, A MEMS microphone in which the longitudinal length of the above bridge is 0.1 mm to 0.3 mm.

5. In Paragraph 1, A MEMS microphone having an adhesive layer disposed between the first substrate and the second substrate.

6. In Paragraph 1, The first substrate comprises one of a 2Metal COF substrate, an FPCB, and a PI-based COF substrate, and The above second substrate is a MEMS microphone comprising a metal substrate.

7. A first substrate array comprising a plurality of first substrate regions spaced apart from each other; A second substrate array stacked on the first substrate array; A plurality of housings each coupled to a plurality of second substrate regions of the second substrate array to form an internal receiving space; and It includes a plurality of MEMS structures each disposed in the receiving space of the plurality of housings, and The above-described second substrate array comprises a plurality of second substrate regions corresponding to the plurality of first substrate regions and a plurality of bridges connecting the plurality of second substrate regions to each other, forming a MEMS microphone array.

8. In Paragraph 7, Each of the plurality of second substrate regions includes a first side, a second side opposite to the first side, a third side connecting the first side and the second side, and a fourth side opposite to the third side. The length of the first side in the longitudinal direction is greater than the length of the third side in the longitudinal direction, and A MEMS microphone array in which the number of bridges formed on the first side is greater than the number of bridges formed on the third side.

9. In Paragraph 7, Each of the plurality of second substrate regions includes a first side, a second side opposite to the first side, a third side connecting the first side and the second side, and a fourth side opposite to the third side. A MEMS microphone array in which the longitudinal length of the bridge formed on the first side is 1 / 20 to 1 / 15 of the longitudinal length of the first side.

10. In Paragraph 7, The first substrate array includes one of a 2Metal COF substrate, an FPCB, and a PI-based COF substrate, and The above second substrate array is a MEMS microphone array comprising a substrate made of metal material.

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