MEMS package and method of manufacturing the same

Abstract

A MEMS package has a MEMS chip and a package substrate to which the MEMS chip is adhered. The MEMS chip has an element substrate on which a movable element is formed. The MEMS package has a dust particle filter formed on the package substrate or the MEMS chip. The dust particle filter has a perforated structure in which a plurality of through holes are regularly arranged on a base surface. In addition, in the dust particle filter, a plane opening ratio is set to at least 45%, and a thickness opening ratio is set to at least 50%.

Description

Technical Field

[0001] The present invention relates to a MEMS package in which a MEMS chip used as a microphone, a sensor, etc. is mounted on a package substrate, and a method of manufacturing the MEMS package. Background Art

[0002] A tiny device called MEMS (micro-electromechanical system) is generally known. MEMS is a device that integrates tiny movable elements and electronic circuits on a substrate (also called an element substrate) made of silicon or the like. Since the entire MEMS is formed in a chip-like form, MEMS is also called a MEMS chip in the present invention. MEMS chips are used as microphones, sensors, actuators, etc.

[0003] For example, a MEMS chip used as a microphone has a diaphragm (membrane, membrane, membrane structure, membrane) and an electrode, the diaphragm is a thin film, the electrode is made of one or two thin films arranged near the diaphragm, and the MEMS chip has a structure formed with a recess for arranging the diaphragm. In the case of a MEMS chip used as a capacitive microphone, the displacement of the diaphragm is detected as a capacitance displacement between the electrodes according to the sound pressure. Therefore, the MEMS chip used as a capacitive microphone works on the principle of a variable capacitor.

[0004] Then, regarding a MEMS package in which a MEMS chip is mounted on a package substrate, generally, the following two structures are known. One is a structure in which a MEMS chip is mounted on a package substrate by FCB (flip chip bonding, for example, see JP2016-523725 (also referred to as Patent Document 1), JP2007-184341 (also referred to as Patent Document 2)), and the other is a structure in which a MEMS chip is mounted on a package substrate by wire bonding (for example, see JP2012-114672 (also referred to as Patent Document 3), JP2012-39272 (also referred to as Patent Document 4)). Summary of the invention

[0005] In the case of using MEMS as a capacitive microphone, there are generally the following two problems caused by dust particles entering from the outside. A) Dust particles hit the diaphragm, thereby damaging the diaphragm. B) Dust particles enter the space between the two electrodes, reducing the function of the variable capacitor. Therefore, conventionally, a microphone module is known in which a thin film (dust particle filter) is formed on the sound hole to prevent dust particles from entering (for example, see USP9565488 (also known as Patent Document 5). In addition, a microphone unit is also known in which a membrane is provided to prevent dust from entering during an installation step, etc. (for example, see Patent Document 4).

[0006] In the case of the microphone module disclosed in Patent Document 5, many through holes are formed in the dust particle filter. It is preferable that the size of the through holes is as small as possible in order to prevent dust particles from entering.

[0007] However, when the size of the through hole is small, it is difficult for air to pass through the dust filter. Then, the sound pressure guided to the MEMS chip may be reduced. In addition, when the thickness of the dust filter is large, the dust filter interferes with the vibration of the air. As a result, the sensitivity of the microphone and microphone characteristics such as SNR (signal to noise ratio) are greatly reduced.

[0008] Therefore, a dust filter is usually required to prevent dust particles from entering in order to avoid the sensitivity of the microphone and the degradation of the microphone characteristics as much as possible. However, the dust filter of the microphone module disclosed in Patent Document 5 cannot achieve the above requirements.

[0009] Furthermore, in the case of the microphone unit disclosed in Patent Document 6, a film that almost covers the opening portion is provided in the mounting step, etc. However, after the microphone unit is mounted on the mounting object, the film is removed. Therefore, dust particles cannot be prevented from entering after mounting.

[0010] As described above, a MEMS chip or a MEMS package used as a microphone or the like needs to effectively prevent dust particles from entering and avoid degradation of sensitivity and microphone characteristics as much as possible even after the MEMS chip is mounted on a mounting object such as a package substrate or the like.

[0011] Therefore, the present invention is to solve the above-mentioned problems, and in the MEMS package and the method for manufacturing the same, one purpose is to effectively prevent dust particles from entering and avoid the decline in sensitivity and microphone characteristics even after the MEMS chip is mounted on a mounting object such as a packaging substrate.

[0012] In order to solve the above problems, the present invention is a MEMS package, comprising: a MEMS chip, and a packaging substrate to which the MEMS chip is adhered; the MEMS chip includes an element substrate on which a movable element is formed, the MEMS package includes a dust particle filter formed on the packaging substrate or the MEMS chip, the dust particle filter includes a perforated structure in which a plurality of through holes are regularly arranged on a base surface, in the dust particle filter, a plane opening ratio defined as the ratio of the size of the plurality of through holes to the size of the base surface is set to at least 45%, and a thickness opening ratio defined as the ratio of the size of the through holes to the thickness of the dust particle filter is set to at least 50%.

[0013] In the case of the above-mentioned MEMS package, the plurality of through holes may be formed to be circular in a plan view, and the planar opening ratio is set by the ratio of the following X2 to the following X1:

[0014] X1: the size of a polygon whose vertices are at least three centers of adjacent representative through-holes among the plurality of through-holes,

[0015] X2: The size of the portion of the representative through hole arranged in the polygon.

[0016] In addition, in the case of the above-mentioned MEMS package, it is preferred that the plurality of through holes are formed into a circular shape in a plan view, the dust particle filter has a first through hole group and a second through hole group, the first through hole group and the second through hole group respectively having a plurality of through holes, the first through hole group having a first through hole, the first through hole being arranged at a position where the interval with the peripheral end portion of the base surface is set to a first interval, and the plurality of through holes are arranged in a straight line at a constant interval, the second through hole group having a second through hole, the second through hole being arranged at a position where the interval with the peripheral end portion is set to a second interval different from the first interval, and the plurality of through holes are arranged in a straight line at a constant interval, and in the dust particle filter, the first line formed by the first through hole group and the second line formed by the second through hole group are arranged alternately.

[0017] In addition, in the case of the above-mentioned MEMS package, it is preferred that the plurality of through holes are formed into a circular shape in a plan view, the dust particle filter has a first through hole group and a second through hole group, the first through hole group and the second through hole group respectively having a plurality of through holes, the first through hole group having a first through hole, the first through hole being arranged at a position where the interval with the peripheral end portion of the base surface is set to a first interval, the plurality of through holes are arranged in a straight line at a constant interval, the second through hole group having a second through hole, the second through hole being arranged at a position where the interval with the peripheral end portion is set to a second interval different from the first interval, the plurality of through holes are arranged in a straight line at a constant interval, and the dust particle filter is formed so that the center of the through holes included in the second through hole group is arranged between the centers of adjacent through holes included in the first through hole group.

[0018] In addition, in the case of the above-mentioned MEMS package, it is preferred that a plurality of adjacent through holes including the following two are arranged to form an equilateral triangle with the center of the plurality of adjacent through holes as a vertex, one of the two being a through hole included in a first through hole group and the other of the two being a through hole included in a second through hole group.

[0019] In addition, preferably, in the dust particle filter, a plurality of adjacent through holes including the following two are arranged to form an equilateral triangle with the centers of the adjacent plurality of through holes as vertices, and the area of ​​the through holes is greater than or equal to 90% of the area of ​​the equilateral triangle, one of the two being a through hole included in a first through hole group, and the other of the two being a through hole included in a second through hole group.

[0020] In addition, preferably, the plurality of through holes are formed into a circular shape in a plan view, the dust particle filter has a plurality of through hole groups, the plurality of through hole groups respectively having a plurality of through holes, the through hole groups having end through holes, the end through holes being arranged at a position such that the interval between the peripheral end portion of the base surface and the end through holes is set to a constant end interval, the plurality of through holes are arranged in a straight line at a constant interval, and in the dust particle filter, adjacent four through holes in two adjacent through hole groups respectively included in the plurality of through hole groups are arranged to form a square with four centers of the adjacent four through holes as vertices, and the area of ​​the through holes is greater than or equal to 45% of the area of ​​the square.

[0021] In addition, the present invention provides a method for manufacturing a MEMS package using a MEMS chip and a packaging substrate to which the packaged MEMS chip is adhered, comprising: a photosensitive adhesive layer forming step, forming a photosensitive adhesive layer made of a photosensitive adhesive on the surface of a packaging board having multiple packaging areas for manufacturing the packaging substrate; a filter chip manufacturing step, for manufacturing a filter chip by performing the following heat removal layer forming step and filter layer forming step, the heat removal layer forming step being used to form a heat removal layer to be removed by heating on a semiconductor chip, the filter layer forming step being used to form a filter layer, wherein multiple filter areas for forming a dust particle filter are formed on the heat removal layer according to an arrangement according to their respective packaging areas; a filter layer removing step, for removing the filter layer together with the heat removal layer from the semiconductor chip by heating the filter chip manufactured by the filter chip manufacturing step; and a filter layer transcription step, for transcribe the filter layer removed by the filter layer removal step onto the packaging board.

[0022] In the case of the above-mentioned method for manufacturing a MEMS package, preferably, the method for manufacturing a MEMS package further includes: a hydrophobicity applying step, applying hydrophobicity to the packaging plate by placing the packaging plate transcribed with the filter layer in a hydrophobic container having a gas phase of a raw material for applying hydrophobicity, and using a hydrophobic gas made from the raw material.

[0023] In addition, preferably, the method for manufacturing a MEMS package further includes: a MEMS chip installation step for installing the MEMS chips respectively on the packaging areas of a packaging board on which the filter layer is transcribed; and a board cutting step for cutting the board with the chip on which the MEMS chip is installed through the MEMS chip installation step into individual packaging areas.

[0024] In addition, the filter chip manufacturing step can form a perforated structure in which multiple through holes are formed in each filter area in a regular arrangement on the base surface as far as the filter layer is concerned, and the planar opening ratio defined as the ratio of the size of the multiple through holes to the size of the base surface is set to at least 45%.

[0025] In addition, the method for manufacturing a MEMS package may further include: a hydrophobicity applying step of applying hydrophobicity to the plate with the chip by placing the plate with the chip in a hydrophobic container having a gas phase of a raw material for applying hydrophobicity, and using a hydrophobic gas made from the raw material.

[0026] In addition, the present invention provides a method for manufacturing a MEMS package using a MEMS chip and a packaging substrate to which the packaged MEMS chip is adhered, comprising: a filter wafer manufacturing step for manufacturing a filter wafer by performing the following heat removal layer forming step and a filter forming step, wherein the heat removal layer forming step is used to form a heat removal layer to be removed by heating on a semiconductor wafer, and the filter layer forming step is used to form a filter layer, wherein the filter layer is formed with a plurality of filter areas for forming a dust particle filter; a photosensitive adhesive layer forming step for forming a photosensitive adhesive layer made of a photosensitive adhesive on the surface of the filter wafer manufactured by the filter wafer manufacturing step; a substrate stacking step for manufacturing a stacked substrate by stacking a MEMS wafer and a filter wafer formed with a plurality of MEMS areas for forming a MEMS chip after performing alignment between each MEMS area and each filter area; and a filter layer transcription step for heating the stacked substrate to remove the semiconductor wafer together with the heat removal layer, and transcribe the filter layer on the MEMS wafer.

[0027] In addition, preferably, the method for manufacturing a MEMS package further includes: a hydrophobicity applying step, applying hydrophobicity to the MEMS chip by placing the MEMS chip transcribed with a filter layer in a hydrophobic container having a gas phase of a raw material for applying hydrophobicity, and using a hydrophobic gas made from the raw material.

[0028] In addition, preferably, the method for manufacturing a MEMS package further includes: a MEMS chip manufacturing step for manufacturing a plurality of MEMS chips by cutting a MEMS wafer transcribed with a filter layer into individual MEMS areas; a MEMS chip mounting step for mounting the MEMS chip manufactured by the MEMS chip manufacturing step on a packaging substrate; and a MEMS chip connecting step for connecting the MEMS chip to the packaging substrate by wire bonding or flip chip bonding.

[0029] In addition, preferably, the filter chip manufacturing step can form a perforated structure on the base surface in which multiple through holes are regularly arranged in each filter area with respect to forming the filter layer, and the planar opening ratio defined as the ratio of the size of the multiple through holes to the size of the base surface is set to at least 45%.

[0030] The present invention will become more fully understood from the detailed description given below and the accompanying drawings, which are given by way of illustration only and, therefore, should not be considered as limiting the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is with Figure 3 A cross-sectional view of a portion corresponding to line 1-1 in FIG. 1 shows a MEMS microphone having a MEMS package according to a first embodiment of the present invention;

[0032] Figure 2 It is enlarged to show Figure 1 A cross-sectional view of the main parts of

[0033] Figure 3 is a plan view showing a main portion of a MEMS microphone with a cap removed;

[0034] Figure 4 is a plan view showing a main part of a dust particle filter;

[0035] Figure 5 is with Figure 4 A cross-sectional view of the portion corresponding to line 5-5;

[0036] Figure 6 is a plan view showing a portion of a plurality of through holes including a dust particle filter, the plurality of through holes including a representative through hole;

[0037] Figure 7 is a plan view showing a portion of a representative through hole including a dust particle filter;

[0038] Figure 8 is a perspective view showing a packaging board according to a first embodiment of the present invention;

[0039] Fig. 9 is a perspective view showing a filter wafer according to a first embodiment of the present invention;

[0040] Fig.10 is a cross-sectional view of a main part showing a filter wafer manufacturing step according to a first embodiment of the present invention;

[0041] Fig.11 It is shown in Fig.10 A cross-sectional view of a main part of a manufacturing step after the middle step;

[0042] Fig.12 It is shown in Fig.11 A cross-sectional view of a main part of a manufacturing step after the middle step;

[0043] Fig.13 It is shown in Fig.12 A cross-sectional view of a main part of a manufacturing step after the middle step;

[0044] Fig.14 is a cross-sectional view of a main part showing a photosensitive adhesive layer forming step according to a first embodiment of the present invention;

[0045] Fig.15 is a cross-sectional view of a main part showing a filter layer removing step according to a first embodiment of the present invention;

[0046] Fig.16 is a cross-sectional view of another main part showing the photosensitive adhesive layer forming step according to the first embodiment of the present invention;

[0047] Fig.17 is a cross-sectional view of a main part showing a filter layer transcription step according to a first embodiment of the present invention;

[0048] Fig.18 is a plan view showing a main part of a dust particle filter according to a modified embodiment;

[0049] Fig.19 is a plan view showing a portion including representative through holes of a dust particle filter according to a modified embodiment;

[0050] Fig. 20 is with Figure 1 a corresponding cross-sectional view showing a MEMS microphone having a MEMS package according to a second embodiment of the present invention;

[0051] Fig.21 is a perspective view showing a MEMS wafer according to a second embodiment of the present invention;

[0052] Fig. 22 is a perspective view showing a filter wafer according to a second embodiment of the present invention;

[0053] Fig.23 is a cross-sectional view of a main part showing a filter wafer manufacturing step according to a second embodiment of the present invention;

[0054] Fig.24 is a cross-sectional view of a main part showing a photosensitive adhesive layer forming step according to a second embodiment of the present invention;

[0055] Fig.25is a cross-sectional view of a main part showing a substrate stacking step according to a second embodiment of the present invention;

[0056] Fig.26 is a cross-sectional view showing a main part of a filter layer transcription step according to a second embodiment of the present invention;

[0057] Fig. 27 It is shown in Fig.26 A cross-sectional view of a main part of a manufacturing step after the middle step;

[0058] Fig.28 It is a graph that plots the relationship between R / T and SNR for multiple dust particle filters;

[0059] Fig.29 is with Figure 1 a corresponding cross-sectional view showing a MEMS microphone having a MEMS package according to a modified embodiment;

[0060] Fig.30 is with Figure 2 The corresponding cross-sectional view shows Fig.29 The MEMS microphone shown in;

[0061] Fig.31 is with Fig. 20 a corresponding cross-sectional view showing a MEMS microphone having a MEMS package according to another modified embodiment; and

[0062] Fig.32 is a cross-sectional view showing a board with a chip according to a first embodiment of the present invention. DETAILED DESCRIPTION

[0063] (First embodiment)

[0064] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the same components will be denoted by the same numerals or letters, and their repeated description will be omitted.

[0065] (MEMS package structure)

[0066] First, refer to Figures 1 to 7 The structure of a MEMS package 1 according to a first embodiment of the present invention is described. Figure 1 is with Figure 3 The cross-sectional view of the portion corresponding to line 1-1 in FIG. 1 shows a MEMS microphone 100 having a MEMS package 1 according to the first embodiment of the present invention, Figure 2 It is enlarged to show Figure 1 A cross-sectional view of the main parts. Figure 3 is a plan view showing the main parts of the MEMS microphone 100 with the cap 99 removed. Figure 4 1 is a plan view showing the main parts of the dust filter 5, Figure 5 is with Figure 4 A cross-sectional view of the portion corresponding to line 5-5. Figure 6 1 is a plan view showing a portion of the particle filter 5 including a plurality of through holes 15 including representative through holes 15a, 15b, 15c. Figure 7 1 is a plan view showing a portion of the particle filter 5 including representative through holes 15a, 15b, 15c.

[0067] like Figure 1 As shown, the MEMS microphone 100 has a MEMS package 1 , an ASIC (Application Specific Integrated Circuit) package 91 , and a cap 99 .

[0068] The MEMS package 1 has a MEMS chip 10 , a package substrate 20 to which the MEMS package 1 is adhered, four bonding bumps 4 , a dust particle filter 5 , and a sound shield 6 .

[0069] The MEMS chip 10 has an element substrate 2 on which a film 3 is formed as a movable element. The MEMS chip 10 is used as a capacitor type microphone. The element substrate 2 is a substrate shaped like a rectangle in a plan view. Figure 3 As shown, the element substrate is formed of silicon. A hole portion 2c is formed in the center of the element substrate 2. The hole portion 2c is formed in a columnar shape from the upper surface 2b (the outer surface of the element substrate 2) of the element substrate 2 to the opposite surface 2a (the surface opposite to the package substrate 20), and the membrane plate 3 is formed on the opposite surface 2a side of the hole portion 2c. Note that two thin films called back plates (not shown) are arranged on the upper and lower sides of the membrane plate 3.

[0070] like Figure 1 As shown, the bonding bumps 4 are solder bumps adhered to the opposite surface 2a and the package substrate 20. The MEMS package 1 has a total of four bonding bumps 4. The four bonding bumps 4 are arranged in the vicinity of the corner portions 2D, 2E, 2F, 2G, respectively.

[0071] The diaphragm is a vibrating film formed in a roughly circular shape and is made of an inorganic metal such as SiO 2 , SiN, etc.

[0072] All four bonding bumps 4 are solder bumps made of solder. Figure 1As shown, four bonding bumps 4 are adhered to both the MEMS chip 10 and the packaging substrate 20. That is, the four bonding bumps 4 are adhered to the electrode pads 7 formed in the opposite surface 2a, and to the electrode pads 21 formed in the packaging surface 20a (the surface of the MEMS chip 10 side of the packaging substrate 20) of the packaging substrate 20. The four bonding bumps 4 electrically connect and secure the MEMS chip 10 to the packaging substrate 20.

[0073] The dust filter 5 is a filter for preventing dust particles from entering. The dust filter 5 is formed on the packaging surface 20a of the packaging substrate 20 to cover the sound hole 20b. The dust filter 5 is a film-like member formed of a polyamide or polyimide film. The dust filter 5 is formed into a modified rectangular shape in which four corner portions are removed, such as Figure 3 , Figure 4 shown.

[0074] The dust filter 5 has a perforated structure, such as Figure 4 , Figure 6 As shown, a plurality of through holes 15 are formed in a regular arrangement on a base surface 16 which is a surface of a film-like member. Figure 5 As shown, each through hole 15 is a hole portion penetrating from the base surface 16 to the rear surface, and the interval between adjacent through holes 15 is a constant value. Figure 4 , Figure 6 , Figure 7 , a plurality of points are shown in the base surface 16. Furthermore, in the case of the dust filter 5, a plane opening ratio described later is set to at least 45%.

[0075] Then, in the dust filter 5, each through hole 15 is formed to be circular in a plan view. The diameter is about 2 μm to 6 μm. In addition, the thickness of the dust filter 5 is about 1 μm to 6 μm. In the dust filter 5, the thickness opening ratio is set to at least 50%, and preferably set to 150%.

[0076] As for the thickness opening ratio, it is defined as the ratio (R / T) of the diameter (R) of the through hole 15 to the thickness (T) of the dust filter 5. Here, the relationship between the R / T of the dust filter 5 and the SNR is as follows: Fig.28 shown. Fig.28 1 is a graph plotting the relationship between R / T and SNR of a plurality of dust filters 5, with the horizontal axis representing R / T and the vertical axis representing SNR. A plurality of dust filters 5 are formed into through holes 15 having different thicknesses (T) and different diameters (R), and the relationship between R / T and SNR of each dust filter 5 is plotted. Fig.28 As shown, when R / T increases, SNR also increases.

[0077] However, since the SNR is almost constant at about 64 to 66 even if R / T exceeds 1.5, R / T is 1.5, that is, R / T is preferably set to 150%. In addition, when R / T becomes 0.5, SNR becomes about 60, and when R / T becomes less than 0.5, SNR is much lower than 60. Therefore, R / T is 0.5, that is, R / T is preferably set to at least 50%.

[0078] The plane opening ratio described later is data indicating how easily air passes through the dust filter 5, and the thickness opening ratio is data indicating how easily air vibrations propagate.

[0079] The dust filter 5 has a first through hole group 15A and a second through hole group 15B. The first through hole group 15A includes a plurality of through holes 15, including a first through hole 15A1, through holes 15A2, 15A3, ... The first through hole 15A1 is arranged at a position where the interval with the peripheral end portion 16e of the base surface 16 is set to a first interval d1, and, among the through holes 15 included in the first through hole group 15A, the first through hole 15A1 is arranged at a position closest to the peripheral end portion 16e. The first through holes 15A1, through holes 15A2, 15A3, ... 15An are arranged in a straight line at a constant interval in a direction perpendicular to the peripheral end portion 16e to form a first line L1.

[0080] The second through hole group 15B includes a plurality of through holes 15, including a second through hole 15B1, a through hole 15B2, and a through hole 15Bn. The second through hole 15B1 is arranged at a position where the interval with the peripheral end portion 16e is set to a second interval d2 greater than the first interval d1, and among the through holes 15 included in the second through hole group 15B, the second through hole 15B1 is arranged at a position closest to the peripheral end portion 16e. The second through holes 15B1, the through holes 15B2, ..., 15Bn are arranged at a constant interval in a direction perpendicularly intersecting the peripheral end portion 16e to form a second line L2.

[0081] Then, in the dust filter 5, the first lines L1 and the second lines L2 are alternately arranged.

[0082] Furthermore, the dust filter 5 is formed so that the center of the through-hole 15 included in the second through-hole group 15B (for example, Figure 4 The through hole 15B2 in the first through hole group 15A is arranged in the adjacent through hole 15 (for example, in Figure 4 In the middle, between the centers of through hole 15A2 and through hole 15A3).

[0083] Here, the plane opening ratio is defined as the ratio of the size of the plurality of through holes 15 to the size of the base surface 16. Specifically, the plane opening ratio is set by the ratio of the following X2 to the following X1.

[0084] X1: the size of a polygon whose vertices are at least three centers of adjacent representative through-holes among the plurality of through-holes 15,

[0085] X2: The size of the portion of the representative through hole arranged in the polygon.

[0086] That is, the size of the open portion that becomes the air path in the particle filter 5 is how big it is, and the data indicating how easy it is for air to pass through is the plane opening ratio.

[0087] The through holes 15 become air passages because the portion between adjacent through holes 15 is the base surface 16 ( Figure 4 Each through hole 15 is arranged regularly. Therefore, the size of the polygon formed by the representative through holes and the size of the portion that becomes the air path are found according to the size of the through holes 15 and the regularity of their arrangement, so that the plane opening ratio can be set.

[0088] Then, in the case of the dust filter 5, as Figure 6 , Figure 7 As shown, three adjacent through holes 15a, 15b, 15c are considered as representative through holes. The centers of through holes 15a, 15b, 15c are a0, b0, c0, but according to the regularity of the arrangement of through holes 15, the triangles with these centers as vertices are regular triangles.

[0089] When the radius of the through holes 15a, 15b, 15c is r and the interval between the through holes 15a, 15b, 15c is a, the area S1 of the triangle (△ABC) with the centers a0, b0, c0 as vertices is:

[0090] S1=(2r+a)×((2r+a)×((√3) / 2)) / 2

[0091] =√3(2r+a) 2 / 4

[0092] In addition, the portions of the through holes 15a, 15b, 15c arranged in △ABC are sectors PA, PB, PC, respectively, and the area S2 of all these sectors PA, PB, PC is:

[0093] S2=πr 2 / 6

[0094] Therefore, the area S3 of the portion where the points are not shown (i.e., the open portion) is:

[0095] S3=(πr2 / 6)×3=πr 2 / 2

[0096] Therefore, the plane opening ratio (OR1) is:

[0097] OR1=S3 / S1

[0098] =(πr 2 / 2) / (√3(2r+a) 2 / 4)

[0099] =πr 2 / (√3(2r+a) 2 / 2)

[0100] When the above OR1 is set to at least 45%,

[0101] πr 2 / (√3(2r+a) 2 / 2)≧1 / 2×0.9

[0102] That is, πr 2 ≧√3(2r+a) 2 / 4×0.9...Equation (1) is sufficient.

[0103] The left side of equation (1) represents the area of ​​the through hole 15. In addition, the right side of equation (1) represents 90% of the area of ​​△ABC. Therefore, in the case of the dust filter 5, the area of ​​the through hole 15 is greater than or equal to 90% of the area of ​​△ABC, so that the plane opening ratio is set to at least 45%. Here, △ABC is an equilateral triangle, which has the centers a0, b0, c0 of the plurality of through holes 15 (15a, 15b, 15c) including the following through holes as vertices: the through holes are both the through holes 15 included in the first through hole group 15A and the through holes 15 included in the second through hole group 15B.

[0104] The ASIC package 91 has an ASIC 92, a package substrate 20 to which the ASIC 92 is attached, and a bonding bump 93. The ASIC 92 is, for example, an integrating circuit that amplifies the output signal of the MEMS chip 10 (an integrating circuit that outputs a displacement of capacitance as a voltage displacement in the MEMS chip 10). The electrode pad 14 is formed on the lower side of the ASIC 92. The electrode pad 14 is connected to the electrode pad 12 of the package surface 20a through the bonding bump 93.

[0105] The package substrate 20 is a plate-like member (or PCB: printed circuit board) made of, for example, silicon, ceramic, etc. Electrode pads 21 and electrode pads 12 are formed on a package surface 20a of the package substrate 20. The MEMS package 1 is mounted on a portion of the package surface 20a where the electrode pads 21 are formed, and the ASIC package 91 is mounted on a portion where the electrode pads 12 are formed. In addition, a sound hole 20b is formed on a portion of the package substrate 20 where the MEMS package 1 is mounted. The sound hole 20b penetrates the package substrate 20 from the package surface 20a to a bottom surface 20c on the opposite side.

[0106] Cap 99 covers MEMS package 1 and ASIC package 91 and is adhered to package surface 20a with an adhesive (or by soldering) not shown. Space 99A is fixed by cap 99 and package substrate 20, and MEMS package 1 and ASIC package 91 are accommodated in space 99A.

[0107] (Method of Manufacturing MEMS Package)

[0108] Then, refer to Figures 8 to 17 A method for manufacturing the MEMS package 1 having the above structure is explained. Here, Figure 8 is a perspective view showing a packaging plate 40 to be described later, Fig. 9 is a perspective view showing a filter wafer 50 described later. Figure 10-13 1 is a cross-sectional view showing a main part of a filter wafer manufacturing step for manufacturing the filter wafer 50. Figure 14-17 It is a cross-sectional view of main parts showing a photosensitive adhesive layer forming step, a filter layer removing step, and a filter layer transferring step.

[0109] In the method for manufacturing the MEMS package 1, the MEMS package 1 is manufactured using the above-mentioned MEMS chip 10 and the package substrate 20 to which the MEMS chip 10 is attached. In the case of the manufacturing method according to the embodiment, the MEMS chip 10 (rectangular MEMS chip) having the rectangular element substrate 2 is used. Figure 8 The packaging board 40 shown and Fig. 9 Filter wafer 50 is shown.

[0110] The package board 40 is a plate-like member having a rectangular shape, made of PCB or ceramic, and a plurality of package areas 41 are formed on a surface 40a in a regular arrangement. When the package board 40 is divided along the dividing line 42, a package substrate 20 is manufactured from each package area 41 (approximately 600 package substrates 20 are manufactured per package board 40).

[0111] Using a semiconductor wafer 49 made of silicon (see Fig.10The filter wafer 50 is formed by forming a filter layer 59 on the semiconductor wafer 49, thereby manufacturing the filter wafer 50. The filter wafer manufacturing step is performed to manufacture the filter wafer 50.

[0112] The method of manufacturing the MEMS package 1 includes a filter wafer manufacturing step, a photosensitive adhesive layer forming step, a filter layer removing step, and a filter layer transferring step.

[0113] The filter wafer manufacturing step includes a heat removal layer forming step and a filter layer forming step.

[0114] In the heat removal layer forming step, first, a semiconductor wafer 49 is prepared. Then, as Fig.10 As shown, a thermal foaming resin is applied on the surface of a semiconductor wafer 49 to form a thermal foaming resin layer. The thermal foaming resin contains resin and a foaming agent. The thermal foaming resin generates gas by heating so that it can foam. When the thermal foaming resin is applied to form the thermal foaming resin layer, the thermal foaming resin layer becomes a heat removal layer 53, which is removed by heating. In addition, the thermal foaming resin layer can be formed by slicing a thermal foaming resin sheet, and the slicing is to process the thermal foaming resin into a sheet form. Specifically, the heat removal layer 53 is formed by applying a heat removal sheet, and the heat removal layer is removed by heating.

[0115] Subsequently, a filter layer forming step is performed. In the filter layer forming step, first, a resin layer 54 is formed on the heat removal layer 53 using a polyamide or polyimide film.

[0116] Next, if Fig.11 As shown in FIG. 1 , a metal layer 55 is formed on the resin layer 54 using titanium (Ti). In addition, a photoresist is applied on the surface of the metal layer 55, and then, it is exposed using a photomask not shown, and further developed to form a resist pattern 56. Next, the metal layer 55 is polished by Ar using the resist pattern 56 as a mask. Then, as shown in FIG. Fig.12 As shown, unnecessary portions of the metal layer 55 are removed to form a metal pattern 55A. The metal pattern 55A is formed by following the pattern of the filter layer 59 to be formed later.

[0117] Then, the resin layer 54 is subjected to reactive ion etching (RIE) using the metal pattern 55A as a mask. Then, the unnecessary portion of the resin layer 54 is removed to form a filter layer 59 on the heat removal layer 53, as shown in FIG. Fig.13 In this way, the filter wafer 50 is manufactured.

[0118] A plurality of filter regions 51 are formed in the filter layer 59 in a regular arrangement according to the encapsulation region 41. A dividing line 52 is arranged between the respective filter regions 51 according to the dividing line 42. The filter portion 58 is arranged in each filter region 51, such as Fig. 9 Because each filter portion 58 subsequently becomes the above-mentioned dust filter 5, a plurality of through holes 15 common to the dust filter 5 are formed in each filter portion 58. The filter portion 58 is formed in a modified rectangular shape according to the dust filter 5.

[0119] On the other hand, in the photosensitive adhesive layer forming step, as Fig.14 As shown in FIG. 1 , a photosensitive adhesive layer 61 is formed on the surface 40a of the package plate member 40. The photosensitive adhesive layer 61 is formed by applying a photosensitive polyimide adhesive sheet or the like. In this case, as shown in FIG. Fig.16 As shown, the photosensitive adhesive layer 61 is formed into a hole-shaped structure in which a portion where the sound hole 20b is to be formed later is removed.

[0120] Then, in the filter layer removing step, first, the filter wafer 50 is heated.

[0121] Then, if Fig.15 As shown, the heat removal layer 53 is foamed by the heat. As a result, the filter layer 59 is removed from the heat removal layer 53.

[0122] Subsequently, the filter layer transcription step is performed. As described above, since the photosensitive adhesive layer 61 is formed on the surface 40a of the packaging board 40, as shown in FIG. Fig.17 As shown, the filter layer 59 removed from the semiconductor wafer 49 is laminated on the photosensitive adhesive layer 61. Then, because a plurality of packaging regions 41 are formed on the packaging board 40, in each packaging region 41, an unnecessary portion of the filter layer 59 is removed by laser processing. In this case, in each packaging region 41, a portion of the filter layer 59 covering the sound hole 20b is preserved, and another portion is removed. In this way, the filter layer 59 is transcribed on the packaging board 40.

[0123] Afterwards, a hydrophobicity application step is performed. In the hydrophobicity application step, the packaged plate 40 transcribed with the filter layer 59 is placed in a container not shown (also referred to as a hydrophobic container), which has a gas phase of a raw material for hydrophobic application. Steam made of a raw material for hydrophobic application (also referred to as a hydrophobic gas) is included in the hydrophobic container. A material including alkylsilane is used as a raw material (see Japanese Patent 3974574, see Patent Document 7 for details). When the hydrophobicity application step is performed, hydrophobicity is applied to the packaged plate 40 transcribed with the filter layer 59.

[0124] Furthermore, in the hydrophobicity applying step, the chip-equipped plate 40X described later can be placed in the hydrophobic container instead of the package plate 40 transcribed with the filter layer 59. Thus, hydrophobicity can be applied to both the filter layer 59 and the membrane plate 3 (another back plate).

[0125] Then, the MEMS chip mounting step is performed. In the MEMS chip mounting step, the electrode pads 7 are formed on the MEMS chip 10, and further solder bumps are formed. Then, in the packaging board 40, the MEMS chips 10 are mounted on the packaging area 41 by flip chip bonding using solder bumps to form a board 40X with chips (see FIG. Fig.32 ). The board 40X with the chip is placed in a heating reflow furnace not shown. Then the solder bumps become the bonding bumps 4 after melting. After that, the sound shield 6 is formed (sometimes the sound shield 6 is formed before mounting the MEMS chip 10). The MEMS package 1 is manufactured by performing the above steps.

[0126] Subsequently, the ASIC package 91 is mounted on the board 40X with chips, further covering the cap 99. Note that when the ASIC package 91 is mounted on the board 40X with chips, package reflow can be performed around the MEMS chip 10 and the ASIC package 91.

[0127] Furthermore, a board cutting step is performed. In the board cutting step, the board 40X with the chip mounted with the MEMS chip 10 and the ASIC package 91 and further covered with the cap 99 is cut along the dividing line 42 to be divided into the respective packaging areas 41. Then, the board 40X with the chip is divided into the plurality of packaging areas 41. The MEMS microphone 100 is manufactured from the respective packaging areas 41 together with the packaging substrate 20. The above-mentioned dust particle filter 5 is formed in the manufactured packaging substrate 20.

[0128] (MEMS package operation and effects)

[0129] As described above, the dust filter 5 is formed on the package substrate 20 of the MEMS package 1. Since the dust filter 5 is formed to cover the sound hole 20b, dust particles can be prevented from entering through the dust filter 5. A plurality of through holes 15 are formed in the dust filter 5, and the diameter of each through hole 15 is about 2 μm to 6 μm. Therefore, the dust filter 5 can reliably prevent dust particles from entering.

[0130] Furthermore, in the case of the particle filter 5, since the plane opening ratio is set to at least 45%, approximately half of the particle filter 5 becomes an air path. Therefore, even if the particle filter 5 is formed, the air path can be reliably ensured. Therefore, the entry of dust particles is effectively prevented while avoiding the decrease in sensitivity and microphone characteristics. Furthermore, since the particle filter 5 is also maintained on the packaging substrate 20, even if the MEMS chip 10 is mounted on the packaging substrate 20, the entry of dust particles is effectively prevented after the MEMS chip is mounted on the packaging substrate 20.

[0131] In particular, the dust filter 5 is formed so that the centers of the through holes 15 included in the second through hole group 15B are arranged between the centers of the adjacent through holes 15 included in the first through hole group 15A. Therefore, in the dust filter 5, the arrangement of the through holes 15 is not wasted, and the air path is effectively ensured.

[0132] Furthermore, since the thickness opening ratio is set to at least 50%, the dust filter 5 has a structure in which its thickness is thin (preferably, the thickness is thinner than the diameter of the through hole 15).

[0133] The conventional dust filter disclosed in Patent Document 5 has a plate-like structure, the thickness of which is thicker than the size of the through hole. Therefore, the conventional dust filter blocks air vibration, which greatly reduces the sensitivity (or SNR) of the microphone.

[0134] In contrast, since the dust filter 5 has a thin structure (preferably thinner than the diameter of the through hole 15), the dust filter 5 hardly disturbs the vibration of the air. Therefore, the MEMS package 1 can avoid the degradation of the sensitivity and microphone characteristics in the diaphragm 3.

[0135] On the other hand, since the air path is effectively ensured in the dust filter 5, moisture can enter from the outside through the dust filter 5. When moisture can enter from the outside, the diaphragm plate 3 adheres to the back plate with moisture, thereby possibly losing the function as a capacitor.

[0136] However, in the MEMS package 1, since hydrophobicity is applied to the package substrate 20, part of the moisture path blocks moisture. Therefore, moisture never enters the diaphragm plate 3 and the back plate. In addition, the dust filter 5 is not damaged by applying hydrophobicity with a hydrophobic gas.

[0137] Furthermore, in the method for manufacturing the MEMS package 1, the filter wafer 50 is used. The filter layer 59 is formed on the semiconductor wafer 49 to manufacture the filter wafer 50. The filter layer 59 of the filter wafer 50 is transcribed to the package board 40, and then the semiconductor wafer 49 used as the filter wafer 50 is retained. The filter layer 59 is formed again on the semiconductor wafer 49, thereby obtaining the filter wafer 50 again. Therefore, in the method for manufacturing the MEMS package 1, the semiconductor wafer 49 is reusable. Therefore, the material used for manufacturing the MEMS package 1 is not wasted, so that the manufacturing cost can be reduced.

[0138] (Modified embodiment)

[0139] Next, refer to Fig.18 , Fig.19 , the dust filter 75 according to the modified embodiment is explained. Fig.18 is a top view showing a main part of a dust filter 75 of a modified embodiment, Fig.19 15 is a plan view showing a portion of a dust filter according to a modified embodiment including representative through holes 15a, 15b, 15c, 15d.

[0140] Compared with the dust filter 5, the difference of the dust filter 75 is that it has a first through hole group 15A, but it does not have a second through hole group 15B. Because the dust filter 75 does not have a second through hole group 15B, a plurality of first lines L1 are arranged. In addition, the first through holes 15A1, through holes 15A2, 15A3 ... 15An included in each through hole group 15A are arranged in a straight line at a constant interval along the direction perpendicularly intersecting the peripheral end portion 16e. In addition, the plurality of first through holes 15A1 included in each first line L1 are arranged in a straight line at a constant interval along the peripheral end portion 16e (through holes 15A2, 15A3 ... 15An are arranged similarly). All intervals between the first through hole 15A1 and the peripheral end portion 16e are constantly set to the end interval d3. The first through hole 15A1 corresponds to the end through hole.

[0141] In the case of the dust filter 75, the plane opening ratio is also set to at least 45%, and the thickness opening ratio is also set to at least 50%. Fig.19 As shown, four adjacent through holes 15a, 15b, 15c, 15d are set as representative through holes. The centers of through holes 15a, 15b, 15c, 15d are a0, b0, c0, d0, and the rectangle with these centers as vertices is a square. When the radius of through holes 15a, 15b, 15c, 15d is r and each interval of through holes 15a, 15b, 15c, 15d is a, the area S4 of the square (□ABCD) with the centers a0, b0, c0, d0 as vertices is:

[0142] S4=(2r+a) 2

[0143] Furthermore, the portions of the through holes 15a, 15b, 15c, 15d arranged in □ABCD are sectors PA, PB, PC, PD, respectively, and the areas S5 of all these sectors PA, PB, PC, PD are:

[0144] S5=πr 2 / 4

[0145] Therefore, in □ABCD, the area S6 of the portion where the points are not shown (i.e., the open portion) is:

[0146] S6=(πr 2 / 4)×4=πr 2

[0147] Therefore, the planar aperture ratio (OR2) is:

[0148] OR2=S6 / S4

[0149] =πr 2 / (2r+a) 2

[0150] When the above OR2 is set to at least 45%,

[0151] πr 2 / (2r+a) 2 ≧1 / 2×0.9

[0152] That is, πr 2 ≥(2r+a) 2 / 2×0.9...Equation (2) is sufficient.

[0153] The left side of equation (2) represents the area of ​​the through hole 15. In addition, the right side of equation (2) represents 90% of half the area of ​​□ABCD (i.e., 45% of the area). Therefore, in the case of the dust filter 75, the area of ​​the through hole 15 is greater than or equal to 45% of the area of ​​□ABCD, so that the plane opening ratio is set to at least 45%. Here, □ABCD is a square with the centers a0, b0, c0, d0 of the adjacent plurality of through holes 15 (15a, 15b, 15c, 15d) included in the adjacent two first through hole groups 15A as vertices.

[0154] In the case of the dust filter 75, since the plane opening ratio is set to at least 45% and the thickness opening ratio is set to at least 50%, similar to the dust filter 5. Therefore, the package substrate 20 formed with the dust filter 75 also exhibits similar operation and effects as the case of forming the dust filter 5.

[0155] (Second embodiment)

[0156] Next, we will refer to Fig. 20 , the structure of the MEMS package 101 according to the second embodiment of the present invention is explained. Here, Fig. 20 is corresponding to Figure 1 , showing a MEMS microphone 200 having a MEMS package 101 .

[0157] like Fig. 20 As shown, MEMS microphone 200 has MEMS package 101 , ASIC package 191 , and cap 99 .

[0158] In the case of the MEMS microphone 100 according to the first embodiment, the MEMS package 1 and the ASIC package 91 are mounted on the package substrate 20 by flip chip bonding.

[0159] In contrast, in the case of the MEMS microphone 200 according to the second embodiment, the MEMS package 101 and the ASIC package 191 are mounted on the package substrate 20 by wire bonding.

[0160] Then, compared with the MEMS package 1 , the MEMS package 101 is different in that the dust filter 5 is formed on the MEMS chip 10 , and it has no bonding bumps 4 , sound holes 6 , electrode pads 7 , 21 , and the MEMS chip 10 is connected to the ASIC 92 through wires 16 .

[0161] Compared to ASIC package 91 , ASIC package 191 is different in that it is connected to package substrate 20 via wires 17 instead of via bonding bumps 93 .

[0162] (Method of Manufacturing MEMS Package)

[0163] Then, refer to Figure 21 to Figure 27 , a method for manufacturing the MEMS package 101 having the above structure is explained. Here, Fig.21 is a perspective view showing a MEMS wafer 140 described later, Fig. 22 is a perspective view showing a filter wafer 150 to be described later. Fig.23 is a cross-sectional view showing a main part of a filter wafer manufacturing step for manufacturing the filter wafer 150, Fig.24 is a cross-sectional view of a main part showing a photosensitive adhesive layer forming step, Fig.25 is a cross-sectional view of a main part showing a substrate stacking step. Fig.26 , 27 is a cross-sectional view showing the main parts of the filter layer transcription step.

[0164] In the method of manufacturing the MEMS package 101, the Fig.21 The MEMS wafer 140 shown and Fig. 22 The filter wafer 150 is shown. In addition, the method of manufacturing the MEMS package 101 includes a filter wafer manufacturing step, a photosensitive adhesive layer forming step, a substrate stacking step, a filter layer transcription step, a MEMS chip manufacturing step, a MEMS chip mounting step and a MEMS chip connecting step.

[0165] The filter wafer 140 is formed using a semiconductor wafer made of silicon. A plurality of MEMS regions 141 are formed in a regular arrangement on the MEMS wafer 140. When the MEMS wafer 140 is divided along scribe lines 142, a MEMS chip 10 is formed from each MEMS region 141 (approximately 10,000-20,000 MEMS chips 10 are formed per wafer).

[0166] Compared with the filter wafer 50, the filter wafer 150 is different in that a filter layer 159 is formed. The filter wafer manufacturing step is performed to manufacture the filter wafer 150, similar to the filter wafer 50. The heat removal layer forming step and the filter layer forming step are included in the filter wafer manufacturing step. In the heat removal layer forming step, as shown in FIG. Fig.23 As shown, a heat removal layer 53 is formed on the surface of the semiconductor wafer 49. Furthermore, a filter layer 159 is formed on the heat removal layer 53 in the filter layer forming step.

[0167] Then, if Fig. 22 As shown, in the filter layer 159, a plurality of filter regions 151 are formed in a regular arrangement according to the MEMS region 141. According to the scribing line 142, a dividing line 152 is arranged between the respective filter regions 151. The filter portion 158 is arranged in each filter region 151. Each filter region 151 does not have a space for arranging two or more filter portions 158. There is no waste for fixing the filter portion 158 with respect to the filter layer 159.

[0168] Then, similar to the filter portion 58, each filter portion 158 later becomes the above-mentioned dust filter 5. A plurality of through holes 15 common to the dust filter 5 are formed in each filter portion 158. The filter portion 158 is formed in accordance with the dust filter 5 into a modified rectangular shape.

[0169] On the other hand, in the photosensitive adhesive layer forming step, as Fig.24As shown, a photosensitive adhesive layer 61 is formed on the surface of the filter wafer 150. The photosensitive adhesive layer 61 is formed by applying a photosensitive polyimide adhesive sheet or the like. In this case, the photosensitive adhesive layer 61 is formed on the surface of the filter wafer 150 in a subsequent hole form structure. In the case of the hole form structure, the photosensitive adhesive layer 61 is shaped so that a circular portion corresponding to the peripheral edge portion of the hole portion 2c of the MEMS chip 10 formed by each MEMS area 141 is retained and the inside of the circular portion is removed. The photosensitive adhesive layer 61 is patterned by exposure and development.

[0170] Furthermore, in the substrate stacking step, as Fig.25 As shown, the stacked substrate 165 is manufactured. In this case, after performing alignment between each MEMS region 141 and each filter region 151, the MEMS wafer 140 and the filter wafer 150 are stacked so that the MEMS wafer 140 and the photosensitive adhesive layer 61 of the filter wafer 150 are stacked, thereby manufacturing the stacked substrate 165.

[0171] In the next filter layer transcription step, first, the stacked substrate 165 is heated. Then, the heat removal layer 53 is foamed by the heat. Fig.26 As shown, the heat removal layer 53 and the semiconductor wafer 49 are removed from the stacked substrate 165. Fig. 27 As shown, the filter layer 159 remains on the photosensitive adhesive layer 61. Thus, the filter layer 159 is transferred onto the MEMS wafer 140.

[0172] After that, a hydrophobicity applying step is performed. In the hydrophobicity applying step, the MEMS wafer 140 transcribed with the filter layer 159 is placed in a hydrophobic container to perform a hydrophobic treatment using a hydrophobic gas. Then, hydrophobicity is applied to the MEMS wafer 140. Therefore, hydrophobicity is applied not only to the dust particle filter 5 but also to the diaphragm plate 3 and the back plate. Therefore, the hydrophobicity application is effectively performed. In addition, because the hydrophobicity application is performed with a hydrophobic gas, the diaphragm plate 3 and the back plate are never damaged.

[0173] In addition, subsequently, a MEMS chip manufacturing step is performed. In the MEMS chip manufacturing step, the MEMS wafer 140 is cut along the scribe line 142. Then, the MEMS wafer 140 is divided into a plurality of MEMS regions 141. The MEMS chip 10 is manufactured from each MEMS region 41. The above-mentioned dust filter 5 is formed in the manufactured MEMS chip 10.

[0174] After that, a MEMS chip mounting step is performed. In the MEMS chip mounting step, the MEMS chip 10 manufactured by the MEMS chip manufacturing step is mounted on the packaging substrate 20. In addition, a MEMS chip connecting step is performed. In the MEMS chip connecting step, the MEMS chip 10 is mounted on the packaging substrate 20 by wire bonding using wires 16, 17. In this way, a MEMS package 101 is manufactured.

[0175] Since the MEMS package 101 has the dust particle filter 5 , similar to the MEMS package 1 , the MEMS package 101 exhibits the same operation and effects as the MEMS package 1 .

[0176] In particular, in the case of the MEMS package 101, since the filter area 151 for forming the dust filter 5 does not have a space for arranging two or more filter parts 158, there is no waste for fixing the filter part 158 ​​with respect to the filter layer 159. Therefore, many MEMS chips 10 formed with the dust filter 5 (i.e., having the dust filter) can be manufactured from one wafer. Therefore, effects such as reduction in manufacturing cost and shortening of manufacturing time are obtained.

[0177] (Another modified embodiment)

[0178] Fig.29 is corresponding to Figure 1 , showing a cross-sectional view of a MEMS microphone 100A having a MEMS package 1A according to a modified embodiment. Fig.30 is corresponding to Figure 2 2 is a cross-sectional view showing a MEMS microphone 100A.

[0179] Compared with the MEMS package 1, the MEMS package 1A is different in that the dust filter 5 is formed on the MEMS chip 10. Since the MEMS package 1A has the dust filter 5, similar to the MEMS package 1, it exhibits the same operation and effects as the MEMS package 1.

[0180] In the case of the MEMS package 1A, the dust filter 5 is formed on the MEMS chip 10. Therefore, the MEMS chip 10 is manufactured by a manufacturing method similar to the MEMS package 101 according to the second embodiment, and further, the MEMS chip 10 is mounted on the package substrate 20 by FCB, thereby manufacturing the MEMS package 1A.

[0181] Fig.31 is corresponding to Fig. 20, showing a MEMS microphone 200A having a MEMS package 101A according to another modified embodiment. Compared with the MEMS package 101, the MEMS package 101A is different in that a dust filter 5 is formed on the package substrate 20. Because the MEMS package 101A has the dust filter 5, similar to the MEMS package 101, it exhibits the same operation and effects as the MEMS package 101.

[0182] In the case of the MEMS package 101A, the dust filter 5 is formed on the package substrate 20. Therefore, the MEMS package 101A is manufactured by using the package board 40 similar to the first embodiment. In this case, the filter layer 59 is transcribed on the package board 40, similar to the first embodiment (for example, see Fig.17 ). Then, the MEMS chip 10 and the like are mounted on the package board 40 by wire bonding, after which a hydrophobicity applying step, a board cutting step, and the like are performed to manufacture the MEMS package 101A.

[0183] In the above-mentioned embodiment, the MEMS package 1 having the diaphragm 3 is exemplarily explained, but the present invention can be applied to another MEMS package. For example, the present invention is also applicable to a MEMS package having a MEMS chip used as a sensor, an actuator, etc. In addition, in this embodiment, it is exemplarily explained that a "double back plate" type having two thin films called back plates not shown are arranged on the upper and lower sides of the diaphragm 3. The present invention is also applicable to a "single back plate" type, having a back plate arranged on one side of the diaphragm 3. In this case, it is sufficient to form two bonding bumps 4. In addition, although the through hole 15 formed as a circular shape in a plan view is exemplarily explained, as a through hole formed in the dust particle filter 5, a through hole formed in a non-circular shape such as a rectangle, a hexagon, etc. can be formed in the dust particle filter. In this case, for the thickness opening ratio, it can be defined as the ratio of the through hole size to the dust particle filter thickness.

[0184] The present invention is not limited to the aforementioned embodiments, and various changes and modifications may be made to its components without departing from the scope of the present invention. In addition, it is apparent that various embodiments and modified embodiments of the present invention may be implemented based on the aforementioned explanations. Therefore, within the scope equivalent to the appended claims, the present invention may be performed in a mode other than the above-mentioned best mode.

Claims

1. A MEMS package, comprising: A MEMS chip, and a packaging substrate to which the MEMS chip is adhered; The MEMS chip includes a component substrate having a film formed thereon. The MEMS package includes a dust filter formed on the package substrate or the MEMS chip. The dust particle filter comprises a perforated structure in which a plurality of through holes are regularly arranged on the surface of the base. wherein, in the dust particle filter, a plane opening ratio is set to at least 45%, and a thickness opening ratio defined as a ratio of a size of the through hole to a thickness of the dust particle filter is set to at least 50%; wherein the plurality of through holes are formed to be circular in plan view, The plane aperture ratio is set by the ratio of the following X2 to the following X1. X1: the size of a polygon whose vertices are at least three centers of adjacent representative through-holes among the plurality of through-holes, X2: The size of the portion of the representative through-hole arranged in the polygon.

2. The MEMS package according to claim 1, in, The plurality of through holes are formed to have a circular shape in a plan view, The dust particle filter has a first through hole group and a second through hole group, and the first through hole group and the second through hole group respectively have a plurality of through holes. wherein the first through hole group has a first through hole arranged at a position where the interval from the peripheral end portion of the base surface is set to a first interval, and the plurality of through holes are arranged in a straight line at a constant interval, wherein the second through hole group has second through holes arranged at a position where the interval from the peripheral end portion is set to a second interval different from the first interval, and the plurality of through holes are arranged in a straight line at a constant interval, Wherein, in the dust particle filter, first lines formed by the first through hole groups and second lines formed by the second through hole groups are arranged alternately.

3. The MEMS package according to claim 1, in, The plurality of through holes are formed to have a circular shape in a plan view, The dust particle filter has a first through hole group and a second through hole group, and the first through hole group and the second through hole group respectively have a plurality of through holes. wherein the first through hole group has a first through hole arranged at a position where the interval from the peripheral end portion of the base surface is set to a first interval, and the plurality of through holes are arranged in a straight line at a constant interval, wherein the second through hole group has a second through hole, the second through hole is arranged at a position where the interval from the peripheral end portion is set to a second interval different from the first interval, and the plurality of through holes are arranged in a straight line at a constant interval, wherein the dust filter is formed such that centers of through holes included in the second through hole group are arranged between centers of adjacent through holes included in the first through hole group.

4. The MEMS package according to claim 2, in, In the dust particle filter, a plurality of adjacent through holes including the following two are arranged to form an equilateral triangle with the center of the plurality of adjacent through holes as a vertex, one of the two being a through hole included in the first through hole group, and the other of the two being a through hole included in the second through hole group.

5. The MEMS package according to claim 2, in, In the dust particle filter, a plurality of adjacent through holes including the following two are arranged to form an equilateral triangle with the center of the plurality of adjacent through holes as a vertex, and the area of ​​the through holes is greater than or equal to 90% of the area of ​​the equilateral triangle, one of the two being a through hole included in the first through hole group, and the other of the two being a through hole included in the second through hole group.

6. The MEMS package according to claim 1, in, The plurality of through holes are formed to have a circular shape in a plan view, The dust particle filter has a plurality of through hole groups, each of which has a plurality of through holes. wherein the through hole group has an end through hole, the end through hole is arranged at a position where the interval between the peripheral end portion of the base surface and the end through hole is set to a constant end interval, and the plurality of through holes are arranged in a straight line at a constant interval, Wherein, in the dust particle filter, four adjacent through holes respectively included in two adjacent through hole groups among the multiple through hole groups are arranged to form a square with four centers of the four adjacent through holes as vertices, and the area of ​​the through holes is greater than or equal to 45% of the area of ​​the square.

7. A method for manufacturing the MEMS package according to claim 1, the method using a MEMS chip and a package substrate to which the MEMS chip is adhered, the method comprising: a photosensitive adhesive layer forming step of forming a photosensitive adhesive layer made of a photosensitive adhesive on a surface of a packaging plate member having a plurality of packaging regions for manufacturing the packaging substrate; a filter wafer manufacturing step for manufacturing a filter wafer by performing a heat removal layer forming step for forming a heat removal layer to be removed by heating on a semiconductor wafer and a filter layer forming step for forming a filter layer, wherein a plurality of filter areas for forming a dust particle filter are formed on the heat removal layer in an arrangement according to respective packaging areas; a filter layer removing step for removing the filter layer together with the heat removal layer from the semiconductor wafer by heating the filter wafer manufactured by the filter wafer manufacturing step; and A filter layer transfer step is used to transfer the filter layer removed by the filter layer removal step onto the packaging plate.

8. The method for manufacturing a MEMS package according to claim 7, further comprising: A hydrophobicity applying step of applying hydrophobicity to the packaging plate by placing the packaging plate having the filter layer transcribed thereon in a hydrophobic container having a gas phase of a raw material for applying hydrophobicity and using a hydrophobic gas made of the raw material.

9. The method for manufacturing a MEMS package according to claim 7, further comprising: A MEMS chip installation step, for installing the MEMS chips respectively on the packaging area of ​​the packaging board on which the filter layer is transcribed; as well as The board cutting step is used to cut the board with the MEMS chip installed in the MEMS chip installation step. The board with the MEMS chip is cut into individual packaging areas.

10. The method for manufacturing a MEMS package according to claim 7, in, The filter wafer manufacturing step forms the filter layer so that a plurality of through holes are formed in each filter region in a perforated structure formed on the base surface in a regular arrangement.

11. The method for manufacturing a MEMS package according to claim 9, further comprising: A hydrophobicity applying step of applying hydrophobicity to the plate with the chip by placing the plate with the chip in a hydrophobic container having a gas phase of a raw material for hydrophobicity applying and using a hydrophobic gas made of the raw material.

12. A method for manufacturing the MEMS package according to claim 1, the method using a MEMS chip and a package substrate to which the MEMS chip is adhered, the method comprising: a filter wafer manufacturing step for manufacturing a filter wafer by performing a heat removal layer forming step for forming a heat removal layer to be removed by heating on a semiconductor wafer and a filter layer forming step for forming a filter layer formed with a plurality of filter regions for forming a dust particle filter; a photosensitive adhesive layer forming step of forming a photosensitive adhesive layer made of a photosensitive adhesive on a surface of the filter wafer manufactured in the filter wafer manufacturing step; a substrate stacking step for manufacturing a stacked substrate by stacking a MEMS wafer and the filter wafer after performing alignment between each MEMS region and each filter region, the MEMS wafer being formed with a plurality of MEMS regions for forming the MEMS chip; as well as A filter layer transfer step is used to heat the stacked substrate to remove the semiconductor wafer together with the heat removal layer, and transfer the filter layer onto the MEMS wafer.

13. The method for manufacturing a MEMS package according to claim 12, further comprising: A hydrophobicity applying step of applying hydrophobicity to the MEMS wafer by placing the MEMS wafer having the filter layer transferred thereto in a hydrophobic container having a gas phase of a raw material for hydrophobicity applying and using a hydrophobic gas made of the raw material.

14. The method for manufacturing a MEMS package according to claim 12, further comprising: MEMS chip manufacturing step for transferring the filter layer The MEMS wafer is cut into individual MEMS regions to manufacture multiple MEMS chips; A MEMS chip mounting step, for mounting the MEMS chip manufactured by the MEMS chip manufacturing step on the packaging substrate; as well as The MEMS chip connection step is used to connect the MEMS chip by wire bonding or flip chip bonding. A MEMS chip is connected to the packaging substrate.

15. The method for manufacturing a MEMS package according to claim 12, in, The filter wafer manufacturing step forms the filter layer so that a plurality of through holes are formed in each filter region in a perforated structure formed on the base surface in a regular arrangement.

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