Package member and sensor device

Abstract

To provide a package member which prevents entry of water into through-holes.SOLUTION: A package member 20 provided herein comprises a substrate 20a. The substrate 20a has a first principal surface 21. The substrate 20a includes a plurality of through-holes H. The plurality of through-holes H is formed to extend from the first principal surface 21 to reach a second principal surface 22 opposite the first principal surface 21. An inner circumference diameter d1 of at least a portion of each through-hole H is 0.5 μm or less.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a packaging member and a sensor device. [Background technology]

[0002] Japanese Patent Application Laid-Open No. 2012-78089 (Patent Document 1) discloses a gas sensor including a gas sensing portion and a breathable cover. The breathable cover includes a metal lid. The metal lid is provided with a plurality of holes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] However, there is a risk that water may enter through the hole when measuring gas in the test object.

[0004] A package member according to an embodiment of the present disclosure includes a substrate. The substrate has a first main surface. The substrate includes a plurality of through holes. The plurality of through holes are formed so as to reach from the first main surface to a second main surface opposite the first main surface. An inner periphery width of at least a portion of the through holes is 0.5 μm or less.

[0005] A sensor device according to an aspect of the present disclosure includes a sensor, a support substrate, and a packaging member, the support substrate holding the sensor therein, and the packaging member is connected to the support substrate. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic cross-sectional view of the sensor device according to the first embodiment. [Diagram 2] FIG. 2 is a partially enlarged cross-sectional view of a region II in FIG. [Diagram 3] FIG. 3 is a schematic cross-sectional view showing a step in the manufacturing method of the sensor device according to the first embodiment. [Figure 4]FIG. 4 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 3 in the method for manufacturing the sensor device according to the first embodiment. [Diagram 5] FIG. 5 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 4 in the method for manufacturing the sensor device according to the first embodiment. [Figure 6] FIG. 6 is a schematic cross-sectional view showing a step subsequent to the step shown in FIG. 5 in the method for manufacturing the sensor device according to the first embodiment. [Figure 7] 7 is a schematic cross-sectional view of a modified example of the sensor device of the first embodiment. [Detailed Description] The details of the embodiments of the present disclosure will be described with reference to the drawings. Note that the same or corresponding parts in the following drawings are given the same reference numerals, and the description thereof will not be repeated. At least some of the configurations of the embodiments described below may be combined in any manner.

[0007] Embodiment 1 <Configuration of the sensor device> Fig. 1 is a schematic cross-sectional view of a sensor device 1 according to embodiment 1. Fig. 2 is a partially enlarged cross-sectional view of a region II in Fig. 1.

[0008] The sensor device 1 shown in FIGS. 1 and 2 is, for example, a gas sensor that detects gas, and mainly includes a support substrate 10, a sensor 15, and a packaging member 20.

[0009] The sensor 15 detects the gas 2 in the surrounding environment of the sensor device 1. Specifically, the sensor 15 detects the gas 2 that has flowed into the cavity 29 of the sensor device 1 through the multiple through holes H of the packaging member 20, and outputs a signal related to the gas 2, such as the concentration of the gas 2. The signal related to the gas 2 is output to the outside of the sensor device 1 through the electrical wiring and external terminals of the support substrate 10. The gas 2 detected by the sensor 15 is not particularly limited, and may be, for example, methane, hydrogen, oxygen, carbon monoxide, or nitrogen oxide (NO x) The sensor 15 is not particularly limited, but is, for example, an environmental sensor. The environmental sensor is a sensor that detects the state quantity of a gas. The environmental sensor detects the state quantity of a gas, such as air pressure, temperature, and wind speed.

[0010] The support substrate 10 supports the sensor 15 and the pad 13. The support substrate 10 is, for example, a printed circuit board. The support substrate 10 has a first surface 10a. The pad 13 is, for example, provided on the first surface 10a. The sensor 15 includes a pad 12. A conductive wire 14, such as a gold (Au) wire, is bonded to the pad 12 and the pad 13. The pad 13 is electrically connected to the pad 12 via the conductive wire 14. A signal related to the gas 2, such as the concentration of the gas 2, is output to the outside of the sensor device 1 through the pad 12, the conductive wire 14, the pad 13, the electrical wiring (not shown) of the support substrate 10, and an external terminal (not shown). The sensor 15 is bonded to the support substrate 10 using a conductive bonding member (not shown) such as a conductive paste.

[0011] In a plan view seen from a direction perpendicular to the first surface 10a, the external terminals are disposed outside the package member 20. The external terminals are connected to electrical wiring of the support substrate 10. The external terminals are connected to the sensor 15 through the electrical wiring of the support substrate 10.

[0012] The package member 20 covers the sensor 15. The package member 20 is formed of a semiconductor material such as silicon (Si). The package member 20 includes a substrate 20a. The substrate 20a has a first main surface 21 and a second main surface 22. The second main surface 22 faces the sensor 15. The first main surface 21 is the surface opposite to the second main surface 22.

[0013] In this specification, a direction perpendicular to the first main surface 21 as shown in FIG.

[0014] The substrate 20a includes a plurality of through holes H. The plurality of through holes H communicates the ambient environment of the sensor device 1 with a cavity 29 of the sensor device 1. Each of the plurality of through holes H is formed so as to reach from the first main surface 21 to the second main surface 22.

[0015] In a plan view seen from the first direction X, the shape of the through hole H may be, for example, a circular shape. When the shape of the through hole H is a circle, the inner circumferential width of the through hole H is the diameter. In a plan view seen from the first direction X, the shape of the through hole H may be, for example, a polygonal shape such as a square shape or a pentagonal shape. In a plan view seen from the first direction X, the shape of the through hole H may be, for example, an elliptical shape.

[0016] The package member 20 is fixed to the support substrate 10 using a bonding member 28. Specifically, the substrate 20a includes a protrusion 25 protruding from the second main surface 22. The protrusion 25 is bonded to the first surface 10a of the support substrate 10 using the bonding member 28. Therefore, even if the first surface 10a of the support substrate 10 is a flat surface, a cavity 29 in which the sensor 15 can be accommodated can be formed between the package member 20 and the support substrate 10.

[0017] Here, the sensor device 1 according to the first embodiment is characterized in that, as shown in FIG. 2, in the package member 20, the inner circumferential width d1 of a part of the through hole H is 0.5 μm or less. As described above, the sensor device 1 detects the state quantity of a gas. The size of a water droplet is generally 100 to 3000 μm. Therefore, when the inner circumferential width d1 of the through hole H is larger than 0.5 μm depending on the atmospheric pressure condition, not only the gas 2 to be inspected but also the water droplets may enter the cavity 29 from the through hole H. If the inner circumferential width d1 of the through hole H is 0.5 μm or less, only the gas 2 to be inspected can pass through the through hole H without the water droplets passing through the through hole H.

[0018] Depending on the environment (such as air pressure) during use of the sensor device 1, water droplets may enter the cavity 29 through the through hole H. Therefore, it is more preferable that the inner circumferential width d1 of the through hole H is 0.2 μm or less. If the inner circumferential width d1 of the through hole H is 0.2 μm or less, the intrusion of water droplets can be sufficiently prevented even if the air pressure during use of the sensor device 1 is 2 atmospheres.

[0019] The inner circumferential width d1 of the through hole H may be a uniform width over the entire area in the first direction X, or may be locally 0.5 μm or less as shown in FIG. 2. Specifically, the substrate 20a has a laminated portion 23. The material constituting the laminated portion 23 may be, for example, silicon. The laminated portion 23 is formed on the first main surface 21 and the inner circumferential surface 24 of the through hole H. The laminated portion 23 has a protruding portion 23a. As shown in FIG. 2, in a cross section of the substrate 20a along the first direction X, the shape of the protruding portion 23a is a curve. The protruding portion 23a is formed so as to protrude from the inner circumferential surface 24 of the through hole H. The protruding portion 23a is formed so as to extend in the circumferential direction with respect to the central axis of the through hole H. Therefore, the inner circumferential width d1 of the through hole H in the region where the protruding portion 23a is formed is smallest in the first direction X.

[0020] There is a risk that water droplets may enter through the through hole H from the first main surface 21 side toward the second main surface 22 side. Therefore, it is preferable that the protrusion 23a is disposed on the first main surface 21 side in the first direction X. In particular, it is more preferable that the inner peripheral width d1 of the through hole H on the first main surface 21 in the first direction X is smallest.

[0021] In order to ensure the mechanical strength of the substrate 20a, as shown in Fig. 2, the through hole H may be formed such that two through holes having different inner peripheral widths are adjacent to each other in the first direction X. Specifically, the through hole H includes a first region Q1 and a second region Q2. The first region Q1 is a region extending from the first main surface 21 to a depth t1 in the first direction X. The second region Q2 is a region extending from the second main surface 22 to a depth t2 in the first direction X. The first region Q1 is adjacent to the second region Q2 in the first direction X.

[0022] 2, a first through hole h1 is formed in the first region Q1. A second through hole h2 is formed in the second region Q2. In a plan view seen from the first direction X, the first through hole h1 is disposed so as to overlap with the second through hole h2. In this manner, the through hole H is formed by the first through hole h1 and the second through hole h2.

[0023] The inner peripheral width d2 of the through hole H in the second region Q2 is larger than the inner peripheral width d1 of the through hole H in the first region Q1. That is, the inner peripheral width d2 of the second through hole h2 is larger than the inner peripheral width d1 of the first through hole h1.

[0024] The protrusion 23a is formed on the first main surface 21 side in the first direction X. Therefore, the inner circumferential width d1 of at least a part of the through hole H in the first region Q1 may be 0.5 μm or less. Therefore, the inner circumferential width d2 of the through hole H in the second region Q2 is larger than 0.5 μm. In this way, the mechanical strength of the substrate 20a is ensured.

[0025] In a plan view seen from the first direction X, the multiple first through holes h1 may be arranged to overlap one second through hole h2. In other words, the multiple first through holes h1 communicate with the surrounding environment of the sensor device 1 and one second through hole h2. In addition, in a plan view seen from the first direction X, the first through holes h1 may be formed at positions that do not overlap the second through holes h2.

[0026] In the first direction X, the depth t2 of the second region Q2 may be greater than the depth t2 of the first region Q1. This further ensures the mechanical strength of the substrate 20a. Specifically, the depth t1 of the first region Q1 may be 50 μm or less. The depth t2 of the second region Q2 may be greater than 50 μm.

[0027] In order to suppress the intrusion of water droplets into the through-hole H, the package member 20 is preferably provided with a water-repellent film 30. Specifically, as shown in FIG. 2, the water-repellent film 30 is preferably formed on the first main surface 21 and the inner circumferential surface 24 of the through-hole H. It is sufficient that the contact angle of water with at least a part of the first through-hole h1 is 90° or more. In particular, it is sufficient that the contact angle of water with the surface of the protrusion 23a is 90° or more. Therefore, it is sufficient that the water-repellent film 30 is formed on the surface of the protrusion 23a, and the water-repellent film 30 does not need to be formed on the first main surface 21. Also, if the substrate 20a has water repellency and the contact angle of water with the surface of the protrusion 23a is 90° or more, the water-repellent film 30 does not need to be formed. The water-repellent film 30 contains a fluorine-based water-repellent agent such as a fluorine resin or a silane containing a perfluoroalkyl group.

[0028] A method for manufacturing the sensor device 1 will now be described. First, the substrate 20a is prepared. The substrate 20a is, for example, a silicon substrate. A resist (not shown) is formed on the surface of the substrate 20a. After patterning the resist, the substrate 20a is etched using the resist as a mask. After etching, the resist on the surface of the substrate 20a is removed. In this manner, a hole ha is formed as shown in FIG. 3. The inner circumferential width da1 of the hole ha is, for example, 1 μm.

[0029] Next, as shown in FIG. 4, the laminated portion 23 is formed by chemical vapor deposition (CVD) or heat treatment. The laminated portion 23 is formed on the surface of the substrate 20a and the hole ha so that the protruding portion 23a is formed. The material constituting the laminated portion 23 is, for example, polysilicon. In this manner, the first through hole h1 is formed. At this time, in the first direction X, the inner circumferential width d1 of the region where the protruding portion 23a is formed is the smallest among the inner circumferential widths of the first through hole h1.

[0030] Next, the substrate 20a is flipped over and mounted so that the laminated portion 23 is connected to the support wafer 40. A resist (not shown) is formed on the second main surface 22. After patterning the resist, the substrate 20a is etched using the resist as a mask. After etching, the resist on the second main surface 22 is removed. In this manner, as shown in FIG. 5, the second through hole h2 is formed. At this time, the etching is performed until the second through hole h2 reaches the first through hole h1. As a result, a through hole H consisting of the first through hole h1 and the second through hole h2 is formed. At this time, when the package member 20 is mounted on the support substrate 10, etching may be performed so that a protrusion 25 is formed on the end side of the substrate 20a so that a cavity 29 is formed (not shown).

[0031] 6, the substrate 20a is separated from the support wafer 40, and a water-repellent treatment is performed on the first main surface 21 and the through-holes H. As a result, a water-repellent film 30 is formed on the first main surface 21 and the inner circumferential surfaces 24 of the through-holes H. In this manner, a packaging member 20 having water-repellent properties is obtained.

[0032] Next, as shown in FIG. 1, the package member 20 is mounted on the support substrate 10 on which the sensor 15 is mounted via a bonding member 28. For example, the package member 20 is bonded to the first surface 10a of the support substrate 10 using the bonding member 28. A cavity 29 is formed between the package member 20 and the support substrate 10. The sensor 15 is accommodated in the cavity 29. A plurality of through holes H of the package member 20 communicate with the ambient environment of the sensor device 1 and the cavity 29. The material constituting the bonding member 28 may be, for example, any one of gold (Au), an aluminum alloy, glass frit, or benzocyclobutene (BCB). In this manner, the sensor device 1 shown in FIG. 1 is obtained.

[0033] FIG. 7 is a schematic cross-sectional view of a modified example of the sensor device 1 of the first embodiment. FIG. 7 corresponds to FIG. 1. The sensor device 1 shown in FIG. 7 basically has the same configuration as the sensor device 1 shown in FIG. 1 and FIG. 2 and can obtain the same effect, but is different in that the package member 20 is mounted directly on the sensor 15, not on the support substrate 10. The sensor device 1 shown in FIG. 7 may be manufactured by the above-mentioned manufacturing method of the sensor device 1. In addition, the package member 20 may be connected to the sensor 15 by any method, and may be connected to the sensor 15 via a joining member 28 as shown in FIG. 7.

[0034] <Action and effect> A package member 20 according to the present disclosure includes a substrate 20a. The substrate 20a has a first main surface 21. The substrate 20a includes a plurality of through holes H. The plurality of through holes H are formed so as to reach from the first main surface 21 to a second main surface 22 opposite the first main surface 21. An inner periphery width d1 of at least a portion of the through hole H is 0.5 μm or less.

[0035] This prevents liquid such as water from entering the through hole H. Therefore, when the sensor device 1 is manufactured using the packaging member 20, only the gas 2 to be inspected can pass through the through hole H without allowing water to pass through the through hole H.

[0036] In the above-mentioned package member 20, the inner circumferential width d1 of at least a part of the through hole H is 0.2 μm or less. In this way, even under high atmospheric pressure (for example, 2 atmospheres), only the gas 2 to be inspected can pass through the through hole H without allowing water to pass through.

[0037] In the above-mentioned package member 20, the through hole H includes a first region Q1 and a second region Q2. A direction perpendicular to the first main surface 21 is defined as a first direction X. The first region Q1 is adjacent to the second region Q2 in the first direction X. An inner peripheral width d1 of at least a part of the through hole H in the first region Q1 is 0.5 μm or less. An inner peripheral width d2 of the through hole H in the second region Q2 is larger than the inner peripheral width d1 of the through hole H in the first region Q1. In this way, the mechanical strength of the substrate 20a is ensured.

[0038] In the above-described package member 20, the depth t2 in the first direction X in the second region Q2 is greater than the depth t1 in the first direction X in the first region Q1. This ensures the mechanical strength of the substrate 20a.

[0039] In the above-mentioned package member 20, the depth t1 in the first region Q1 is 50 μm or less. In this way, the mechanical strength of the substrate 20a is ensured.

[0040] In the above-mentioned package member 20, the depth t2 in the second region Q2 exceeds 50 μm. In this way, the mechanical strength of the substrate 20a is ensured.

[0041] In the above-described packaging member 20, the contact angle of water with at least a part of the inner circumferential surface 24 of the through hole H is equal to or greater than 90°. In this manner, the inner circumferential surface 24 of the through hole H has water repellency, which further suppresses the infiltration of liquids such as water into the through hole H.

[0042] The packaging member 20 includes a water-repellent film 30. The water-repellent film 30 is formed on at least a part of the inner circumferential surface 24 of the through-hole H. By forming the water-repellent film 30 on the inner circumferential surface 24 of the through-hole H, the contact angle of water becomes 90° or more. As a result, the packaging member 20 can have high water repellency.

[0043] In the package member 20, a protrusion 23a is formed on an inner circumferential surface 24 of the through hole H. In a cross section of the substrate 20a taken along the first direction X, the shape of the protrusion 23a is curved. In this manner, a part of the through hole H may have a region where the inner circumferential width d1 is locally small.

[0044] The sensor device 1 according to the present disclosure includes a sensor 15, a support substrate 10, and a packaging member 20. The support substrate 10 holds the sensor 15 therein. The packaging member 20 is connected to the support substrate 10. In this manner, when the sensor device 1 is produced using the packaging member 20, only the gas 2 to be inspected can pass through the through hole H without allowing water to pass through the through hole H.

[0045] The sensor device 1 according to the present disclosure includes a sensor 15 and a packaging member 20. The packaging member 20 is directly connected to the sensor 15. In this manner, when the sensor device 1 is produced using the packaging member 20, only the gas 2 to be tested can pass through the through hole H without allowing water to pass through the through hole H.

[0046] In the sensor device 1, the sensor 15 is an environment sensor that detects the state quantity of a gas. In this way, the state quantity of the gas to be inspected (gas 2) can be detected without passing water through the through hole H.

[0047] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. Unless inconsistent, at least two of the embodiments disclosed herein may be combined. The basic scope of the present disclosure is indicated by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0048] Various aspects of the present disclosure are summarized below as appendices. (Appendix 1) A substrate having a first major surface, the substrate includes a plurality of through holes formed so as to reach from the first main surface to a second main surface opposite to the first main surface, The packaging member, wherein at least a part of the through hole has an inner periphery width of 0.5 μm or less. (Appendix 2) 2. The packaging member of claim 1, wherein an inner periphery width of at least a part of the through hole is 0.2 μm or less. (Appendix 3) the through hole includes a first region and a second region; If a direction perpendicular to the first main surface is defined as a first direction, the first region is adjacent to the second region in the first direction, an inner circumferential width of at least a portion of the through hole in the first region is 0.5 μm or less; 3. The packaging member of claim 1, wherein an inner circumferential width of the through hole in the second region is greater than an inner circumferential width of the through hole in the first region. (Appendix 4) 4. The packaging member of claim 3, wherein a depth in the second region is greater than a depth in the first region in the first direction. (Appendix 5) 5. The packaging member of claim 3 or 4, wherein the first region has a depth of 50 μm or less. (Appendix 6) 6. The packaging member of any one of claims 3 to 5, wherein the depth of the second region is greater than 50 μm. (Appendix 7) 7. The packaging member according to claim 1, wherein a contact angle of water with at least a part of the inner circumferential surface of the through hole is 90° or more. (Appendix 8) 8. The packaging member of claim 7, further comprising a water-repellent film formed on at least a portion of the inner circumferential surface of the through hole. (Appendix 9) a protrusion is formed on the inner circumferential surface of the through hole, In a cross section of the substrate taken along the first direction, 7. The packaging member of any one of claims 3 to 6, wherein the protrusion has a curved shape. (Appendix 10) A sensor; A support substrate that holds the sensor therein; A sensor device comprising: a packaging member according to any one of claims 1 to 9, connected to the supporting substrate. (Appendix 11) A sensor; and a packaging member according to any one of claims 1 to 9, directly connected to the sensor. (Appendix 12) 12. The sensor device according to claim 10 or 11, wherein the sensor is an environmental sensor that detects a state quantity of a gas. [Explanation of symbols]

[0049] 1 sensor device, 2 gas, 10 support substrate, 10a first surface, 12, 13 pads, 14 conductive wire, 15 sensor, 20 package member, 20a substrate, 21 first main surface, 22 second main surface, 23 laminated portion, 23a protrusion, 24 inner peripheral surface, 25 convex portion, 28 bonding member, 29 cavity, 30 water-repellent film, 40 support wafer, H through hole, Q1 first region, Q2 second region, X first direction, Y second direction, Z third direction, d1, d2, da1 inner peripheral width, h1 first through hole, h2 second through hole, ha hole, t1, t2 depth.

Claims

1. A substrate having a first major surface, the substrate includes a plurality of through holes formed so as to reach a second main surface opposite to the first main surface, The packaging member, wherein at least a part of the through hole has an inner periphery width of 0.5 μm or less.

2. The packaging member according to claim 1 , wherein an inner periphery width of at least a part of the through hole is 0.2 μm or less.

3. the through hole includes a first region and a second region; If a direction perpendicular to the first main surface is defined as a first direction, the first region is adjacent to the second region in the first direction, an inner circumferential width of at least a portion of the through hole in the first region is 0.5 μm or less; The packaging member according to claim 1 , wherein an inner peripheral width of the through hole in the second region is larger than an inner peripheral width of the through hole in the first region.

4. The packaging member of claim 3 , wherein the second region has a greater depth in the first direction than the first region.

5. 5. The packaging member of claim 4, wherein the first region has a depth of 50 [mu]m or less.

6. 6. The packaging member of claim 5, wherein the depth in the second region is greater than 50 [mu]m.

7. The packaging member according to claim 1 , wherein a contact angle of water with at least a part of the inner circumferential surface of the through hole is 90° or more.

8. The packaging member according to claim 7 , further comprising a water-repellent film formed on at least a part of the inner circumferential surface of the through hole.

9. a protrusion is formed on the inner circumferential surface of the through hole, In a cross section of the substrate taken along the first direction, The packaging member according to claim 3 , wherein the protrusion has a curved shape.

10. A sensor; A support substrate that holds the sensor therein; A sensor device comprising: the package member according to claim 1 , connected to the support substrate.

11. A sensor; A sensor device comprising: a packaging member according to claim 1 directly connected to the sensor.

12. The sensor device according to claim 10 , wherein the sensor is an environmental sensor that detects a state quantity of a gas.

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