JP2015100886A - Electronic device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic device and electronic equipment which can detect a temperature of a function element with a simple structure.SOLUTION: An electronic device 1 includes: an MEMS substrate 2 having an MEMS element 7 and a metal wall 89 for surrounding at least a part of the MEMS element 7; and an IC substrate 3 having a temperature detection element 34 and a multilayer wiring layer 32 with a plurality of wiring layers laminated. The multilayer wiring layer 32 includes wiring 35 for temperature detection which is electrically connected to the metal wall 89. The wiring 35 for temperature detection includes a temperature transmission part 351 arranged around the temperature detection element 34.

Description

  The present invention relates to an electronic device and an electronic apparatus.

  2. Description of the Related Art In recent years, electronic devices such as sensors, resonators, and communication devices that use MEMS (Micro Electro Mechanical System) technology and have a MEMS element on a semiconductor substrate have attracted attention. As such an electronic device, an electronic device having a substrate, a MEMS element formed on the substrate, and an element surrounding structure provided on the substrate and defining a cavity in which the MESM element is disposed is known. (For example, refer to Patent Document 1).

  In such an electronic device, it is known that the vibration characteristic (vibration frequency) of the MEMS element changes due to thermal expansion or the like, and temperature compensation is required to correct the change in the vibration characteristic. As a temperature compensation method, a method is known in which a temperature sensor is formed in the vicinity of a MEMS element, and a signal obtained from the MEMS element is corrected according to the temperature detected by the temperature sensor (for example, see Patent Document 2). However, there is a problem that the structure of the electronic device becomes complicated and the manufacturing of the electronic device becomes complicated because the work of forming the temperature sensor in the vicinity of the MEMS element is added.

2008-2221435 gazette 2009-267365

  An object of the present invention is to provide an electronic device and an electronic apparatus that can detect the temperature of a functional element with a simple configuration.

Such an object is achieved by the present invention described below.
An electronic device of the present invention includes a first substrate having a functional element and a metal wall surrounding at least a part of the functional element,
A second substrate having a temperature sensing element and a multilayer wiring layer in which a plurality of wiring layers are stacked;
The multilayer wiring layer includes a temperature detection wiring electrically connected to the metal wall,
The temperature detection wiring includes a temperature transmission portion provided around the temperature detection element.
As a result, an electronic device that can detect the temperature of the functional element with a simple configuration is obtained.

In the electronic device according to the aspect of the invention, it is preferable that the temperature transmission unit is provided in a wiring layer other than the wiring layer located farthest from the temperature detection element among the plurality of wiring layers.
Thereby, the temperature of the functional element can be detected more accurately.
In the electronic device according to the aspect of the invention, it is preferable that the temperature detection element is configured by a diffusion resistor.
This simplifies the configuration of the temperature detecting element.

In the electronic device according to the aspect of the invention, it is preferable that the temperature transmission unit is provided in a wiring layer closest to the temperature detection element among the plurality of wiring layers.
Thereby, the temperature of the functional element can be detected more accurately.
In the electronic device according to the aspect of the invention, it is preferable that the temperature transmission unit overlaps the temperature detection element in a plan view of the second substrate.
This simplifies the configuration of the temperature detecting element.

In the electronic device according to the aspect of the invention, it is preferable that the temperature detection element is configured by a thin film resistor.
This simplifies the configuration of the temperature detecting element.
In the electronic device according to the aspect of the invention, it is preferable that the temperature transmission unit overlaps the temperature detection element in a direction orthogonal to the thickness direction of the second substrate.
Thereby, the temperature of the functional element can be detected more accurately.

In the electronic device of the present invention, it is preferable that the first substrate and the second substrate are provided so as to overlap in the thickness direction.
Thereby, size reduction of an electronic device can be achieved.
In the electronic device according to the aspect of the invention, it is preferable that the metal wall and the temperature detection wiring are bonded via a conductive bonding member.
Thereby, heat can be efficiently transferred from the metal wall to the temperature detection wiring.

In the electronic device of the present invention, the joining member is preferably a conductive paste having conductivity.
Thereby, the structure of a joining member becomes simple. Moreover, since a joining member can be comprised softly, the stress addition to a functional element can be suppressed.
In the electronic device of the present invention, the conductive paste is preferably a silver paste.
Thereby, it becomes a joining member which has the outstanding heat conductivity.

In the electronic device of the present invention, it is preferable that the metal wall and the temperature detection wiring are directly joined.
Thereby, heat can be efficiently transferred from the metal wall to the temperature detection wiring.
An electronic apparatus according to the present invention includes the electronic device according to the present invention.
As a result, a highly reliable electronic device can be obtained.

1 is a cross-sectional view of an electronic device according to a first embodiment of the present invention. It is sectional drawing of the MEMS board | substrate which the electronic device shown in FIG. 1 has. It is sectional drawing for demonstrating the manufacturing method of the MEMS board | substrate shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the MEMS board | substrate shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the MEMS board | substrate shown in FIG. It is sectional drawing of the IC substrate which the electronic device shown in FIG. 1 has. It is sectional drawing which shows the electronic device which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows the electronic device which concerns on 3rd Embodiment of this invention. It is sectional drawing which shows the electronic device which concerns on 4th Embodiment of this invention. 1 is a perspective view illustrating a configuration of a mobile (or notebook) personal computer to which an electronic apparatus of the present invention is applied. It is a perspective view which shows the structure of the mobile telephone (PHS is also included) to which the electronic device of this invention is applied. It is a perspective view which shows the structure of the digital still camera to which the electronic device of this invention is applied. It is a perspective view which shows the motor vehicle as a moving body.

Hereinafter, an electronic device and an electronic apparatus of the present invention will be described in detail based on each embodiment shown in the accompanying drawings.
1. Electronic Device <First Embodiment>
FIG. 1 is a cross-sectional view of an electronic device according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of the MEMS substrate included in the electronic device shown in FIG. 3 to 5 are cross-sectional views for explaining a method of manufacturing the MEMS substrate shown in FIG. 6 is a cross-sectional view of an IC substrate included in the electronic device shown in FIG. In the following, for convenience of explanation, the upper side of FIGS. 1 to 6 is also referred to as “upper” and the lower side is also referred to as “lower”.
As shown in FIG. 1, the electronic device 1 includes a MEMS substrate (first substrate) 2 and an IC substrate (second substrate) 3.

≪MEMS substrate≫
As shown in FIG. 2, the MEMS substrate 2 includes a substrate 6, a MEMS element (functional element) 7, and an element surrounding structure 8 that surrounds the MEMS element 7. Such a MEMS substrate 2 is effective in that it can be manufactured by a semiconductor process (CMOS process). Hereinafter, each part will be described sequentially.

-Board-
The substrate 6 is a plate member having a substantially square or substantially rectangular shape in plan view. Such a substrate 6 is configured, for example, by laminating an insulating film 62 and a silicon nitride film 63 in this order on a semiconductor substrate 61 such as a silicon substrate. Instead of the semiconductor substrate 61, a ceramic substrate, a glass substrate, a sapphire substrate, a diamond substrate, a synthetic resin substrate, or the like may be used. Moreover, the planar view shape of the board | substrate 6 is not limited to the above rectangles, For example, a circle may be sufficient and a polygon more than a pentagon may be sufficient.

-MEMS element-
The MEMS element 7 has a fixed electrode 71 and a movable electrode 72 formed on the substrate 6. Among these, the movable electrode 72 includes a support portion 721 formed on the silicon nitride film 63 of the substrate 6, a movable portion 722 arranged to face the fixed electrode 71 with a gap, a support portion 721, and a movable portion 722. And a connecting portion 723 for connecting the two. In such a movable electrode 72, the movable portion 722 is cantilevered by the support portion 721 via the connecting portion 723, and the movable portion 722 and the connecting portion 723 constitute a vibration system 724.

When a high frequency having a frequency equivalent to the natural frequency of the vibration system 724 is applied between the movable electrode 72 and the fixed electrode 71, the movable portion 722 vibrates (resonates) while the connecting portion 723 is elastically deformed, A current flows between the fixed electrode 71 and the movable portion 722, and the current is output (detected) from the fixed electrode 71.
The fixed electrode 71 and the movable electrode 72 are electrically connected to a wiring layer 82 (described later) via electric wiring (not shown) formed on the silicon nitride film 63.

-Element surrounding structure-
The element surrounding structure 8 is formed so as to define the cavity 5 in which the MEMS element 7 is disposed. The environment in the cavity 5 is not particularly limited, and may be, for example, a reduced pressure state (preferably a vacuum state) or a gas filled state filled with an inert gas such as nitrogen or argon.
The element surrounding structure 8 has a box-shaped (dome-shaped) metal wall 89 that faces (faces) the cavity 5 and covers the periphery (side and upper side) of the MEMS element 7. As will be described later, the metal wall 89 functions as a heat conductive wiring used for detecting the temperature of the MEMS element 7.

  Such an element surrounding structure 8 includes an interlayer insulating film 81 formed on the substrate 6 so as to surround the MEMS element 7 and a wiring layer 82 formed on the interlayer insulating film 81 (through the interlayer insulating film 81). An interlayer insulating film 83 formed on the wiring layer 82 and the interlayer insulating film 81 so as to surround the MEMS element 7, and a wiring layer 84 formed on the interlayer insulating film 83 (interlayer insulating film 83). An interlayer insulating film 85 formed on the wiring layer 84 and the interlayer insulating film 83 so as to surround the MEMS element 7, and formed on the interlayer insulating film 85 and covering the cavity 5 with a lid A wiring layer 86 (including a through via penetrating the interlayer insulating film 85), a surface protection film 87 formed on the wiring layer 86 and the interlayer insulating film 85, and a wiring layer 86. Sealing layer 88 formed and It has.

  In such an element surrounding structure 8, the metal wall 89 described above is formed by the wiring layers 82, 84, 86 and the sealing layer 88. With such a configuration, the metal wall 89 can be formed at the same time in the step of forming the wiring layers 82, 84, 86 and the sealing layer 88. A process becomes unnecessary and manufacture of the MEMS substrate 2 becomes easy. The metal wall 89 is not electrically connected to the MEMS element 7 and is in an electrically floating state. Thereby, since heat_generation | fever of the metal wall 89 at the time of supplying with electricity to the MEMS element 7 is prevented, the temperature of the MEMS element 7 can be detected more accurately.

Hereinafter, in order to distinguish from the metal wall 89, the wiring formed by the wiring layers 82, 84, 86 and electrically connected to the MEMS element 7 is also referred to as “electric wiring 80”.
The wiring layer 86 has a coating layer 861 that covers the cavity 5, and a plurality of pores (openings) 861 a are formed in the coating layer 861. A sealing layer 88 is provided so as to cover the covering layer 861, the pores 861 a are closed by the sealing layer 88, and the cavity 5 is sealed. The covering layer 861 and the sealing layer 88 constitute a ceiling portion of the metal wall 89.

Each of the wiring layers 82, 84, 86 and the sealing layer 88 is preferably made of a material having conductivity and high thermal conductivity. Examples of such materials include various metal materials such as gold (Au), silver (Ag), copper (Cu), and aluminum (Al). As described above, since the metal wall 89 is formed by the wiring layers 82, 84, 86 and the sealing layer 88, the metal wall 89 exhibits excellent thermal conductivity by using the above materials. can do. Therefore, the electronic device 1 can detect the temperature of the MEMS element 7 more accurately.
The configuration of the MEMS substrate 2 has been described above.

Hereinafter, a method for manufacturing the MEMS substrate 2 having such a configuration will be briefly described.
[Functional element formation process]
First, as shown in FIG. 3A, a semiconductor substrate 100 made of a semiconductor such as a silicon substrate is prepared. Next, the surface of the prepared semiconductor substrate 100 is thermally oxidized to form a silicon oxide film (insulating film) 110, and a silicon nitride film 120 is formed on the silicon oxide film 110 by sputtering, CVD, or the like. Thereby, the substrate 6 is obtained.

  Next, as shown in FIG. 3B, a polycrystalline (or amorphous) silicon film 200 for forming the fixed electrode 71 is formed on the silicon nitride film 120 by sputtering, CVD, or the like. The crystalline (or amorphous) silicon film 200 is doped with an impurity such as phosphorus to impart conductivity. Then, a photoresist is applied on the polycrystalline (or amorphous) silicon film 200 and patterned into the shape of the fixed electrode 71 to form a photoresist film 210.

Next, after etching the polycrystalline (or amorphous) silicon film 200 using the patterned photoresist film 210 as a mask, the photoresist film 210 is removed. Thereby, as shown in FIG.3 (c), the fixed electrode 71 is formed.
Next, as shown in FIG. 3D, a sacrificial layer 220 made of a silicon oxide film, PSG (phosphorus doped glass) or the like is formed by a thermal oxidation method, a sputtering method, a CVD method or the like so as to cover the fixed electrode 71. To do.

Next, as shown in FIG. 3E, a polycrystalline (or amorphous) silicon film 230 for forming the movable electrode 72 is formed on the silicon nitride film 120 and the sacrificial layer 220 by sputtering, CVD, or the like. Then, the formed polycrystalline (or amorphous) silicon film 230 is doped with an impurity such as phosphorus to impart conductivity. Then, a photoresist is applied on the polycrystalline (or amorphous) silicon film 230 and patterned into the shape of the movable electrode 72 (a shape in plan view) to form a photoresist film 240.
Next, after the polycrystalline (or amorphous) silicon film 230 is etched using the photoresist film 240 as a mask, the photoresist film 240 is removed. Thereby, the movable electrode 72 is formed as shown in FIG.
As described above, the MEMS element 7 and the sacrificial layer 220 are formed on the substrate 6.

[Insulating film formation process]
First, as shown in FIG. 4B, an interlayer insulating film 900 made of a silicon oxide film is formed on the silicon nitride film 120 and the MEMS element 7 by a sputtering method, a CVD method, or the like. In addition, an annular opening 901 surrounding the MEMS element 7 in a plan view of the semiconductor substrate 100 and a columnar opening 902 are formed in the interlayer insulating film 900 by patterning or the like. The opening 901 is a hole for forming the metal wall 89, and the opening 902 is a hole for forming the electric wiring 80.

  Next, as shown in FIG. 4C, a wiring layer 910 is formed by patterning after forming a layer made of, for example, aluminum on the interlayer insulating film 900 by sputtering, CVD, or the like. A part of the wiring layer 910 is electrically connected to a wiring (wiring drawn from the MEMS element 7) formed on the semiconductor substrate 100 through the opening 902.

Next, as shown in FIG. 4D, an interlayer insulating film 920, a wiring layer 930, and an interlayer insulating film 940 are sequentially formed. The interlayer insulating films 920 and 940 can be formed by a method similar to that of the above-described interlayer insulating film 900, and the wiring layer 930 can be formed by a method similar to the wiring layer 910.
Such a laminated structure of the interlayer insulating film and the wiring layer is formed by a normal CMOS process, and the number of laminated layers is appropriately set as necessary. In other words, more wiring layers may be stacked via an interlayer insulating film as necessary.

[Coating layer forming step]
As shown in FIG. 5A, a wiring layer 950 is formed by forming a layer made of, for example, aluminum on the interlayer insulating film 940 by a sputtering method, a CVD method, or the like and then performing a patterning process. A part of the wiring layer 950 is located above the MEMS element 7 and constitutes a coating layer 951 in which a plurality of pores 952 are formed.

  Next, as shown in FIG. 5B, a surface protective film 960 made of, for example, a silicon nitride film, a resist, or other resin material is formed on the wiring layer 950 and the interlayer insulating film 940 by sputtering, CVD, or the like. . The surface protective film 960 includes a plurality of film layers containing one or more kinds of materials, and is formed so as not to seal the pores 952 of the coating layer 951. The constituent material of the surface protective film 960 is formed of a material having resistance for protecting the element from moisture, dust, scratches, and the like, such as a silicon oxide film, a silicon nitride film, a polyimide film, and an epoxy resin film.

[Release process]
First, as shown in FIG. 5C, after performing a protective film forming step such as a photoresist for release etching, the interlayer on the MEMS element 7 is passed through a plurality of pores 952 formed in the covering layer 951. The insulating films 900, 920, and 940 are removed, and the sacrificial layer 220 between the fixed electrode 71 and the movable electrode 72 is removed. Thereby, the cavity 5 in which the MEMS element 7 is disposed is formed, and the fixed electrode 71 and the movable electrode 72 are separated from each other, so that the MEMS element 7 can be driven.

  The interlayer insulating films 900, 920, and 940 and the sacrificial layer 220 are removed by, for example, wet etching that supplies hydrofluoric acid, buffered hydrofluoric acid, or the like as an etchant from the plurality of pores 952, or etching gas from the plurality of pores 952. Can be performed by dry etching to supply hydrofluoric acid gas or the like. In addition, after removing the interlayer insulating films 900, 920, and 940, the sacrificial layer 220, and the resist film, the inside of the cavity 5 may be cleaned as necessary.

[Sealing process]
Finally, a sealing layer 970 made of a silicon oxide film, a silicon nitride film, a metal film such as Al, Cu, W, Ti, or TiN is formed on the coating layer 951 by sputtering, CVD, or the like. The hole 952 is sealed.
Through the steps as described above, the MEMS substrate 2 shown in FIG. 2 can be manufactured.

≪IC board≫
The IC substrate 3 is a multilayer wiring board, and includes a substrate 31 and a multilayer wiring layer 32 formed on the substrate 31 as shown in FIG.
-Board-
The substrate 31 is a plate member having a substantially square or substantially rectangular shape in plan view. Such a substrate 31 is configured, for example, by laminating an insulating film 312 and a silicon nitride film 313 in this order on a semiconductor substrate 311 such as a silicon substrate. However, the planar view shape of the substrate 31 is not particularly limited, and may be, for example, a circle, a pentagon or more polygon, or an irregular shape.

  Further, on the substrate 31, a semiconductor circuit (not shown) that is electrically connected to the MEMS element 7 (electrical wiring 80) provided on the MEMS substrate 2 is formed. This semiconductor circuit includes at least a temperature detection element 34 for detecting the temperature of the MEMS element 7, and other active elements such as MOS transistors, capacitors, inductors, resistors, Circuit elements such as a diode and wiring (including wiring layers 322, 324, and 326 described later) are included.

In the present embodiment, the temperature detection element 34 is configured by a diffusion resistor. Such a temperature detection element 34 can be formed, for example, by doping the semiconductor substrate 311 with impurities such as boron, phosphorus, and arsenic. As described above, by forming the temperature detection element 34 with a diffusion resistor, the formation of the temperature detection element 34 is simplified.
The arrangement of the temperature detection element 34 is not particularly limited, but is preferably arranged so as to overlap the cavity 5 in a plan view of the electronic device 1. Thereby, the temperature detection element 34 can be brought close to the MEMS element 7, and the temperature detection of the MEMS element 7 by the temperature detection element 34 can be performed more accurately.

−Multilayer wiring layer−
The multilayer wiring layer 32 includes an interlayer insulating film 321 formed on the substrate 31, a wiring layer 322 (including a through via penetrating the interlayer insulating film 321) formed on the interlayer insulating film 321, a wiring layer 322, and Interlayer insulating film 323 formed on interlayer insulating film 321, wiring layer 324 (including a through via penetrating interlayer insulating film 323) formed on interlayer insulating film 323, wiring layer 324 and interlayer insulating film 323 An interlayer insulating film 325 formed above and a wiring layer 326 (including a through via penetrating the interlayer insulating film 325) formed on the interlayer insulating film 325 are configured. However, the number of stacked interlayer insulating films and wiring layers is not limited to this.

  The multilayer wiring layer 32 is provided with a temperature detection wiring 35 for enabling the temperature detection element 34 to detect the temperature of the MEMS element 7. The temperature detection wiring 35 is electrically (thermally) connected to the metal wall 89 provided on the MEMS substrate 2 so that the heat of the metal wall 89 is transmitted. Here, as described above, the metal wall 89 faces the cavity portion 5 and is located in the vicinity of the MEMS element 7, and therefore can be said to be in the substantially same temperature environment as the MEMS element 7 accommodated in the cavity portion 5. Therefore, it can be estimated that the metal wall 89 has substantially the same temperature as the MEMS element 7, and the temperature detection element 34 detects the heat of the temperature detection wiring 35 to which the heat of the metal wall 89 is transmitted. The temperature of the MEMS element 7 can be detected.

  The temperature detection wiring 35 includes a temperature transmission part 351 located around the temperature detection element 34 and a connection part 352 located on the wiring layer 326 which is the uppermost layer of the multilayer wiring layer 32 and facing the outside. The temperature transmission unit 351 is provided in the wiring layer 322 that is closest to the temperature detection element 34 (that is, the lowermost layer) among the wiring layers 322, 324, and 326. Further, the temperature transmission unit 351 is provided so that at least a part of the temperature transmission unit 351 overlaps the temperature detection element 34 in a plan view of the IC substrate 3. Thereby, since the temperature transmission part 351 can be arrange | positioned in the vicinity of the temperature detection element 34, the temperature of the MEMS element 7 can be detected more accurately by the temperature detection element 34.

  In addition, if the temperature transmission part 351 is not provided in the wiring layer 326 located farthest from the temperature detection element 34 (that is, the uppermost layer) among the plurality of wiring layers 322, 324, and 326, wiring is performed. For example, the wiring layer 324 may not be provided. Even if it is such a structure, although accuracy falls compared with this embodiment, the temperature of the MEMS element 7 can fully be detected. Note that the distance between the temperature detection element 34 and the temperature transmission unit 351 is not particularly limited, and is preferably about 0.1 to 2.0 μm, for example, although it varies depending on the material of the interlayer insulating film.

  By forming the temperature detection wiring 35 in the wiring layers 322, 324, and 326, the temperature detection wiring 35 can be formed at the same time in the process of forming the wiring layers 322, 324, and 326. A separate process for forming the IC substrate is not required, and the manufacture of the IC substrate 3 is facilitated. The temperature detection wiring 35 is not electrically connected to the semiconductor circuit built in the IC substrate 3 and is in an electrically floating state. Accordingly, the temperature detection wiring 35 is prevented from being heated by energization of the semiconductor circuit, so that the temperature of the MEMS element 7 can be detected with higher accuracy.

Hereinafter, in order to distinguish from the temperature detection wiring 35, the wiring formed by the wiring layers 322, 324, and 326 and electrically connected to the semiconductor circuit is also referred to as “electric wiring 320”.
Here, each of the wiring layers 322, 324, and 326 is preferably made of a material having conductivity and high thermal conductivity. Examples of such materials include various metal materials such as gold (Au), silver (Ag), copper (Cu), and aluminum (Al). As described above, since the temperature detection wiring 35 is formed by the wiring layers 322, 324, and 326, the temperature detection wiring 35 exhibits excellent thermal conductivity by using the above materials. be able to. Therefore, the electronic device 1 can detect the temperature of the MEMS element 7 more accurately.
The configuration of the IC substrate 3 has been described above.
Such an IC substrate 3 can be manufactured by a normal (known) semiconductor process. Therefore, the description of the manufacturing method of the IC substrate 3 is omitted.

≪Member state of MEMS substrate and IC substrate≫
In the electronic device 1, the MEMS substrate 2 and the IC substrate 3 are joined in a state where they overlap in the thickness direction. Thereby, size reduction of the electronic device 1 can be achieved. In the present embodiment, the MEMS substrate 2 and the IC substrate 3 are bonded by the conductive bonding member 4. Thereby, joining of the MEMS substrate 2 and the IC substrate 3 can be performed easily and firmly.

  The bonding member 4 includes a first bonding member 41 that bonds the metal wall 89 (sealing layer 88) and the temperature detection wiring 35 (connection portion 352), a wiring layer 86 (electric wiring 80), and a wiring layer 326 (electrical). And a second joining member 42 for joining the wiring 320). Therefore, the metal wall 89 and the temperature detection wiring 35 are electrically (thermally) connected via the first bonding member 41, and the electric wiring 80 and the electric wiring 320 are connected via the second bonding member 42. Are electrically connected.

  The first and second joining members 41 and 42 are not particularly limited as long as the above functions can be exhibited. For example, metals such as gold (Au), silver (Ag), and copper (Cu), silver brazing Metal brazing materials such as copper brazing, phosphor copper brazing, solder, etc., metal pastes such as silver paste and copper paste (in which metal particles are dispersed in an organic solvent), and the like can be used. Among these, in particular, the first bonding member 41 is preferably as soft as possible, and in this respect, it is more preferable to use a metal paste. Thereby, the stress addition to the MEMS element 7 can be suppressed, and the MEMS element 7 can exhibit desired vibration characteristics. Furthermore, as the 1st joining member 41, it is preferable to use a silver paste from the point which is excellent in thermal conductivity among metal pastes. Thereby, since the heat of the metal wall 89 can be efficiently transmitted to the temperature detection wiring 35, the temperature of the MEMS element 7 can be detected more accurately by the temperature detection element 34.

  According to the electronic device 1 as described above, since the temperature detecting element is not provided on the MEMS substrate 2 side, the manufacturing of the MEMS substrate 2 is simplified and the configuration of the MEMS substrate 2 is simplified. In addition, since the metal wall 89 and the temperature detection wiring 35 can effectively transmit heat equivalent to the heat received by the MEMS element 7 to the temperature detection element 34 provided on the IC substrate 3, the MEMS element 7 temperature can be detected accurately.

Second Embodiment
Next, a second embodiment of the electronic device of the present invention will be described.
FIG. 7 is a sectional view showing an electronic device according to the second embodiment of the present invention.
Hereinafter, the second embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.
The second embodiment is the same as the first embodiment described above except that the method of joining the metal wall and the temperature detection wiring is different.

  As shown in FIG. 7, in the electronic device 1 of the present embodiment, the metal wall 89 (sealing layer 88) and the temperature detection wiring 35 (connection portion 352) are directly bonded by surface activation bonding. Thereby, for example, the heat of the metal wall 89 can be efficiently transmitted to the temperature detection wiring 35 as much as the first joining member 41 as in the first embodiment described above is not interposed. Therefore, the temperature detection element 34 can detect the temperature of the MEMS element 7 more accurately. In the surface active bonding, for example, first, the bonding surfaces (that is, the surface of the sealing layer 88 and the surface of the connection portion 352) of the metal wall 89 and the temperature detection wiring 35 are smoothed by polishing or the like, and then This is a bonding method in which the bonding surface between the metal wall 89 and the temperature detection wiring 35 is activated by irradiating an ion beam or the like, and then the bonding surfaces of the metal wall 89 and the temperature detection wiring 35 are brought into contact with each other and pressed. Since such a method can be performed at room temperature, it is excellent in that it does not cause temperature damage to the MEMS element 7 and the like.

<Third Embodiment>
Next, a third embodiment of the electronic device of the present invention will be described.
FIG. 8 is a sectional view showing an electronic device according to the third embodiment of the present invention.
Hereinafter, the third embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

The third embodiment is the same as the first embodiment described above except that the configuration of the temperature detection element and the configuration of the temperature detection wiring are different.
As shown in FIG. 8, the temperature detection element 34 is formed on a substrate 31 and is constituted by a thin film resistor such as a polysilicon thin film. Thereby, formation of the temperature detection element 34 becomes easy.

Further, the temperature transmission portion 351 included in the temperature detection wiring 35 is provided so as to overlap the temperature detection element 34 in a direction orthogonal to the thickness direction of the IC substrate 3 (that is, in the horizontal direction or the depth direction in the drawing). . In other words, the temperature detection element 34 and the temperature transmission part 351 are provided in the same plane with the thickness direction as a normal line. Thereby, since the temperature transmission part 351 can be arrange | positioned in the vicinity of the temperature detection element 34, the temperature of the MEMS element 7 can be detected more accurately by the temperature detection element 34.
Note that the arrangement of the temperature transmission unit 351 is not limited to the arrangement of the present embodiment, and for example, a plurality of the temperature transmission parts 351 may be provided around the temperature detection element 34, and the ring shape surrounds the temperature detection element 34. It may be.

<Fourth embodiment>
Next, a fourth embodiment of the electronic device of the present invention will be described.
FIG. 9 is a cross-sectional view showing an electronic device according to the fourth embodiment of the present invention.
Hereinafter, the fourth embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.
The fourth embodiment is the same as the first embodiment described above except that the configuration of the MEMS substrate is different.

As shown in FIG. 9, in the MEMS substrate 2 of the electronic device 1 of the present embodiment, it is thinner than the surrounding portion at a position overlapping the cavity 5 of the substrate 6 (position overlapping the MEMS element 7). A diaphragm portion 65 that is bent and deformed is provided. The diaphragm portion 65 is formed by providing a bottomed recess 651 on the upper surface of the semiconductor substrate 61. Such a diaphragm portion 65 can have a plan view shape such as a circle or a rectangle, and the upper surface thereof serves as a pressure receiving surface 652. The thickness of the diaphragm portion 65 is not particularly limited, but is preferably 10 μm or more and 50 μm or less, and more preferably 15 μm or more and 25 μm or less. Thereby, the diaphragm part 65 can fully bend and deform | transform.
In this embodiment, the recess 651 does not penetrate the semiconductor substrate 61, and the diaphragm portion 65 is configured by three layers of the semiconductor substrate 61, the insulating film 62, and the silicon nitride film 63. For example, the recess 651 May penetrate the semiconductor substrate 61, and the diaphragm portion 65 may be composed of two layers of an insulating film 62 and a silicon nitride film 63.

  Such an electronic device 1 can be used as a pressure sensor. That is, in such an electronic device 1, the diaphragm portion 65 is deformed in accordance with the pressure received by the pressure receiving surface 652 of the diaphragm portion 65, whereby the gap G between the movable portion 722 of the movable electrode 72 and the fixed electrode 71 is increased. Change. Since the resonance frequency of the MEMS element 7 in which the gap G changes changes, the magnitude of the pressure received by the pressure receiving surface 652 can be obtained from the change in the resonance frequency. In particular, when the cavity 5 is in a vacuum state, a pressure sensor capable of detecting absolute pressure is obtained.

2. Next, an electronic apparatus to which the electronic device 1 of the present invention is applied will be described.
FIG. 10 is a perspective view showing the configuration of a mobile (or notebook) personal computer to which the electronic apparatus of the present invention is applied. In this figure, a personal computer 1100 includes a main body portion 1104 provided with a keyboard 1102 and a display unit 1106 provided with a display portion 1108. The display unit 1106 is rotated with respect to the main body portion 1104 via a hinge structure portion. It is supported movably. Such a personal computer 1100 incorporates an electronic device 1 that functions as a filter, a resonator, a reference clock, a pressure sensor, and the like.

  FIG. 11 is a perspective view showing a configuration of a mobile phone (including PHS) to which the electronic apparatus of the invention is applied. In this figure, a cellular phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204, and a mouthpiece 1206, and a display unit 1208 is disposed between the operation buttons 1202 and the earpiece 1204. Such a cellular phone 1200 incorporates an electronic device 1 that functions as a filter, a resonator, a reference clock, a pressure sensor, and the like.

  FIG. 12 is a perspective view showing the configuration of a digital still camera to which the electronic apparatus of the present invention is applied. In this figure, connection with an external device is also simply shown. Here, an ordinary camera sensitizes a silver halide photographic film with a light image of a subject, whereas a digital still camera 1300 photoelectrically converts a light image of a subject with an imaging device such as a CCD (Charge Coupled Device). An imaging signal (image signal) is generated.

  A display unit 1310 is provided on the back of a case (body) 1302 in the digital still camera 1300, and is configured to perform display based on an imaging signal from the CCD. The display unit 1310 displays a subject as an electronic image. Functions as a viewfinder. A light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided on the front side (the back side in the drawing) of the case 1302.

  When the photographer confirms the subject image displayed on the display unit and presses the shutter button 1306, the CCD image pickup signal at that time is transferred and stored in the memory 1308. In the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. As shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312 and a personal computer 1440 is connected to the input / output terminal 1314 for data communication as necessary. Further, the imaging signal stored in the memory 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation. Such a digital still camera 1300 incorporates an electronic device 1 that functions as a filter, a resonator, a reference clock, a pressure sensor, and the like.

  In addition to the personal computer (mobile personal computer) shown in FIG. 10, the mobile phone shown in FIG. 11, and the digital still camera shown in FIG. Inkjet printers), laptop personal computers, televisions, video cameras, video tape recorders, car navigation devices, pagers, electronic notebooks (including those with communication functions), electronic dictionaries, calculators, electronic game devices, word processors, workstations, televisions Telephone, crime prevention TV monitor, electronic binoculars, POS terminal, medical equipment (for example, electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish detector, various measuring devices, instruments Class (eg, vehicle, navigation Aircraft, gauges of a ship), can be applied to a flight simulator or the like.

4). Next, a moving body to which the electronic device of the present invention is applied will be described.
FIG. 13 is a perspective view showing an automobile as a moving body. An electronic device 1 is mounted on the automobile 1500. Electronic device 1 includes keyless entry, immobilizer, car navigation system, car air conditioner, anti-lock brake system (ABS), air bag, tire pressure monitoring system (TPMS), engine control, hybrid car, The present invention can be widely applied to electronic control units (ECUs) such as battery monitors for electric vehicles, vehicle body posture control systems, and the like.
As mentioned above, although the electronic device and the electronic apparatus of the present invention have been described based on the illustrated embodiment, the present invention is not limited to this, and the configuration of each part is of an arbitrary configuration having the same function Can be substituted. In addition, any other component may be added to the present invention. Moreover, you may combine each embodiment suitably.

  DESCRIPTION OF SYMBOLS 1 ... Electronic device 2 ... MEMS substrate 3 ... IC substrate 31 ... Substrate 311 ... Semiconductor substrate 312 ... Insulating film 313 ... Silicon nitride film 32 ... Multi-layer wiring layer 320 ... Electric wiring 321 ... Interlayer Insulating film 322 ... Wiring layer 323 ... Interlayer insulating film 324 ... Wiring layer 325 ... Interlayer insulating film 326 ... Wiring layer 34 ... Temperature sensing element 35 ... Temperature sensing wiring 351 ... Temperature transmission part 352 ... ... Connection part 4 ... Joining member 41 ... First joining member 42 ... Second joining member 5 ... Hollow part 6 ... Substrate 61 ... Semiconductor substrate 62 ... Insulating film 63 ... Silicon nitride film 65 ... Diaphragm portion 651 …… Concavity portion 652 …… Pressure receiving surface 7 …… MEMS element 71 …… Fixed electrode 72 …… Moving electrode 721 …… Supporting portion 722 …… Moving portion 723 …… Continuous Connection portion 724 …… Vibration system 8 …… Element surrounding structure 80 …… Electric wiring 81 …… Interlayer insulating film 82 …… Wiring layer 83 …… Interlayer insulating film 84 …… Wiring layer 85 …… Interlayer insulating film 86 …… Wiring layer 861 …… Coating layer 861a …… Pore 87 …… Surface protective film 88 …… Sealing layer 89 …… Metal wall 100 …… Semiconductor substrate 110 …… Silicon oxide film 120 …… Silicon nitride film 200 …… Silicon Film 210 ... Photoresist film 220 ... Sacrificial layer 230 ... Silicon film 240 ... Photoresist film 900 ... Interlayer insulating film 901 ... Opening 902 ... Opening 910 ... Wiring layer 920 ... Interlayer insulating film 930... Wiring layer 940... Interlayer insulating film 950... Wiring layer 951... Covering layer 952... Fine pore 960 ... Surface protective film 970. …… Personal computer 1102 …… Keyboard 1104 …… Main body 1106 …… Display unit 1108 …… Display unit 1200 …… Mobile phone 1202 …… Operation buttons 1204 …… Earpiece 1206 …… Speaker 1208 …… Display unit 1300 …… Digital still camera 1302 …… Case 1304 …… Light receiving unit 1306 …… Shutter button 1308 …… Memory 1310 …… Display unit 1312 …… Video signal output terminal 1314 …… Input / output terminal 1430 …… TV monitor 1440 …… Personal Computer 1500 …… Automobile G …… Gap

Claims (13)

A first substrate having a functional element and a metal wall surrounding at least a part of the functional element;
A second substrate having a temperature sensing element and a multilayer wiring layer in which a plurality of wiring layers are stacked;
The multilayer wiring layer includes a temperature detection wiring electrically connected to the metal wall,
The electronic device according to claim 1, wherein the temperature detection wiring includes a temperature transmission portion provided around the temperature detection element.   2. The electronic device according to claim 1, wherein the temperature transmission unit is provided in a wiring layer other than the wiring layer located farthest from the temperature sensing element among the plurality of wiring layers.   The electronic device according to claim 1, wherein the temperature detection element is configured by a diffused resistor.   The electronic device according to claim 3, wherein the temperature transmission unit is provided in a wiring layer closest to the temperature detection element among the plurality of wiring layers.   5. The electronic device according to claim 3, wherein the temperature transmission unit overlaps the temperature detection element in a plan view of the second substrate.   The electronic device according to claim 1, wherein the temperature detection element is configured by a thin film resistor.   The electronic device according to claim 6, wherein the temperature transmission unit overlaps the temperature detection element in a direction orthogonal to a thickness direction of the second substrate.   The electronic device according to claim 1, wherein the first substrate and the second substrate are provided so as to overlap in the thickness direction.   The electronic device according to any one of claims 1 to 8, wherein the metal wall and the temperature detection wiring are joined via a conductive joining member.   The electronic device according to claim 9, wherein the bonding member is a conductive paste having conductivity.   The electronic device according to claim 10, wherein the conductive paste is a silver paste.   The electronic device according to claim 1, wherein the metal wall and the temperature detection wiring are directly joined.   An electronic apparatus comprising the electronic device according to claim 1.

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