JP6897455B2 - Electronic devices and manufacturing methods for electronic devices - Google Patents

Description

The present invention relates to an electronic device and a method for manufacturing the electronic device.

As a method of sealing a cavity around an element in a semiconductor device or electronic device including an element such as a transistor, which is formed by using a semiconductor substrate, Patent Document 1 describes a semiconductor substrate in which the element and a filter having a mesh structure are formed. A cover film covering the device is provided while forming a cavity between the device and the device, and a thin film covering the filter from the back surface side of the semiconductor substrate via the via hole is provided on the via hole that reaches the filter from the back surface side of the semiconductor substrate. A method for manufacturing a semiconductor device that seals a cavity around an element with good airtightness in a short time by forming the device is disclosed.

Japanese Unexamined Patent Publication No. 2009-170588

However, in the manufacturing method described in Patent Document 1, when a thin film covering a filter having a mesh structure is formed through a via hole in order to seal a cavity around an element, a thin film for sealing is released from the mesh portion of the filter. There is a problem that it enters the cavity, adheres to the surface of the element, and deteriorates its characteristics.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following forms or application examples.

[Application Example 1] In the electronic device according to this application example, the element portion is accommodated in an accommodation space composed of a first main surface of the element substrate and a lid portion joined to the first main surface. The electronic device is composed of a recess having an opening on the second main surface side of the element substrate opposite to the first main surface, a bottom portion of the recess, and the first main surface. The membrane portion is provided with a sealing hole penetrating the membrane portion, and the first surface of the membrane portion on the first main surface side and the sealing hole are , A second surface (bottom of the recess) of the membrane portion, which is covered with a porous first sealing portion and is on the second main surface side of the membrane portion, and the first sealing portion of the first sealing portion. The sealing portion surface on the main surface side of No. 2 is covered with the second sealing portion.

According to this application example, the accommodating space composed of the element substrate and the lid portion is covered with a porous first sealing portion from the accommodating space side in a sealing hole provided in the element substrate, and the first By covering the sealing portion surface on the sealing hole side of the sealing portion with a second sealing portion of metal, airtight sealing can be performed. Since the first sealing portion that closes the sealing hole from the accommodation space side is porous, the particles of the second sealing portion may pass through the inside of the first sealing portion and reach the accommodation space. Can not. That is, the first sealing portion is composed of a large number of pores that are intricately connected. Therefore, during the film formation of the second sealing portion, the particles of the second sealing portion adhere to a large number of pores constituting the first sealing portion, so that the particles do not enter the accommodation space. Therefore, when the accommodation space is airtightly sealed, it is possible to reduce the particles of the second sealing portion from adhering to the element portion and deteriorating the characteristics of the element portion, and an electronic device having stable characteristics can be obtained. Obtainable.

[Application Example 2] In the electronic device described in the above application example, the first sealing portion is preferably a sputtered film of aluminum oxide.

According to this application example, since the first sealing portion is aluminum oxide, a porous aluminum oxide sputtered film can be easily formed by sputtering aluminum oxide.

[Application Example 3] In the electronic device described in the above application example, the second sealing portion is preferably a metal film or a metal oxide film.

According to this application example, since the second sealing portion is a metal film or a metal oxide film, a dense film can be easily formed and the accommodation space can be maintained with high airtightness.

[Application Example 4] In the electronic device described in the above application example, it is preferable that the metal film extends from a conductive film disposed on the second main surface.

According to this application example, it is possible to form a second sealing portion for airtightly sealing the accommodation space at the same time as forming the conductive film disposed on the second main surface, and high productivity can be obtained. it can.

[Application Example 5] The method for manufacturing an electronic device according to this application example includes a substrate preparation step of preparing an SOI substrate on which an element portion is formed, and a first method on the side of the SOI substrate on which the element portion is formed. A first sealing portion forming step of forming a porous first sealing portion on the main surface, and a lid portion forming an accommodation space for the element portion are provided on the first main surface of the SOI substrate. In the lid joining step of joining and in the formation region of the first sealing portion of the SOI substrate in a plan view, an opening is made on the second main surface side of the SOI substrate opposite to the first main surface. A recess forming step of forming the recess forming the membrane portion by the SOI substrate and a part of the bottom portion of the recess are removed from the second main surface side opposite to the first main surface of the SOI substrate. A sealing hole forming step of forming a sealing hole in the membrane portion, a sealing step of setting the accommodation space as a predetermined space environment, and airtightly sealing the sealing hole with a second sealing portion of metal. It is characterized by including.

According to this application example, a porous first sealing portion is formed on the SOI substrate on which the element portion is formed, and the lid portion is joined and then sealed at a position overlapping the first sealing portion of the SOI substrate. By forming the holes and covering the sealing holes with the second sealing portion, the accommodation space formed by the SOI substrate and the lid portion and accommodating the element portion can be hermetically sealed. Since the first sealing portion is porous, when the sealing hole is hermetically sealed with the second sealing portion of the metal, the second sealing portion of the metal is the first sealing portion. It cannot reach the containment space through the interior of the building. That is, the first sealing portion is composed of a large number of pores that are intricately connected. Therefore, during the film formation of the second sealing portion, the particles of the second sealing portion adhere to a large number of pores constituting the first sealing portion, so that the particles do not enter the accommodation space. Therefore, when the accommodation space is airtightly sealed, it is possible to reduce the particles of the second sealing portion from adhering to the element portion and deteriorating the characteristics of the element portion, so that an electronic device having stable characteristics can be obtained. Can be manufactured.

[Application Example 6] In the method for manufacturing an electronic device according to the above application example, it is preferable that the sealing step includes a conductive film forming step of forming a conductive film on the second main surface side.

According to this application example, it is possible to form a second sealing portion that airtightly seals the accommodation space at the same time as forming the conductive film formed on the second main surface, and high productivity can be obtained. ..

The plan view which omitted the lid part of the electronic device which concerns on 1st Embodiment. The cross-sectional view which shows the cross section of the line AA in FIG. A partially enlarged view of part B in FIG. The flowchart which shows the manufacturing method of the electronic device which concerns on 1st Embodiment. The cross-sectional view which shows the manufacturing process of the electronic device which concerns on 1st Embodiment. The cross-sectional view which shows the manufacturing process of the electronic device which concerns on 1st Embodiment. The cross-sectional view which shows the manufacturing process of the electronic device which concerns on 1st Embodiment. The cross-sectional view which shows the manufacturing process of the electronic device which concerns on 1st Embodiment. The cross-sectional view which shows the manufacturing process of the electronic device which concerns on 1st Embodiment. The cross-sectional view which shows the manufacturing process of the electronic device which concerns on 1st Embodiment. The cross-sectional view which shows the structure of the electronic device which concerns on 2nd Embodiment. The flowchart which shows the manufacturing method of the electronic device which concerns on 2nd Embodiment. The cross-sectional view which shows the structure of the electronic device which concerns on 3rd Embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each of the drawings shown below, in order to make each component large enough to be recognized on the drawing, the dimensions and ratios of each component may be described differently from the actual components as appropriate. is there.

<First Embodiment>
[Structure of electronic device]
First, the electronic device 1 according to the first embodiment will be described with reference to FIGS. 1, 2, and 3.
FIG. 1 is a plan external view in which the lid 20 of the electronic device 1 according to the first embodiment is omitted, and FIG. 2 is a cross-sectional view showing a cross section of the line AA in FIG. Is a partially enlarged view of part B in FIG. In addition, in FIGS. 1 to 3 and 5 to 11 and 13 shown below, the X axis, the Y axis, and the Z axis are shown as three axes orthogonal to each other.

As shown in FIGS. 2 and 3, the electronic device 1 according to the first embodiment has a so-called SOI (Silicon on Insulator) in which a silicon oxide layer is inserted between a silicon substrate layer and a silicon layer of single crystal silicon. An element substrate 10 formed of a substrate, or a semiconductor substrate such as a silicon substrate whose main material is single crystal silicon, as a substrate material M (not shown), and a lid joined to a first main surface 10a of the element substrate 10. A unit 20 and a unit 20 are provided.

The lid portion 20 has a lid portion cavity 21 on the side of the element substrate 10 facing the first main surface 10a, and the first main surface 10a of the element substrate 10 and the joint surface 20a of the lid portion 20 are joined. As a result, a part of the accommodation space S is formed. The material of the lid portion 20 is not particularly limited, but glass is preferably used.

The element substrate 10 is _{composed of an element forming layer 11 in which a silicon oxide (SiO 2} ) layer and a silicon (Si) layer of an SOI substrate are laminated, and a base 12 of the silicon (Si) layer. The element substrate 10 is formed by a so-called MEMS (Micro Electro Mechanical System), for example, an element portion 13 such as an oscillator is formed, and a base cavity 16 is formed at a base portion 12 of a formation region of the element portion 13. The base cavity 16 and the lid cavity 21 of the lid 20 form a storage space S for accommodating the element portion 13.

A porous first sealing portion 30 is provided on the first main surface 10a of the outer shell portion of the base cavity 16 of the element substrate 10. Further, in a plan view from the direction in which the element substrate 10 and the lid portion 20 overlap (when viewed from the Z-axis direction), the first main surface 10a is located in the region overlapping the first sealing portion 30 of the element substrate 10. A recess 17 that opens on the side of the second main surface 10b opposite to the above is provided, and has a membrane portion 15 composed of a bottom portion 17a of the recess 17 and a first main surface 10a. That is, the membrane portion 15 is formed in the element forming layer 11, and a sealing hole 14 penetrating the membrane portion 15 is provided in the central portion.

The first surface 15a and the sealing hole 14 on the first main surface 10a side of the membrane portion 15 are covered with the porous first sealing portion 30, and the second main surface of the membrane portion 15 is covered. The second surface 15b (bottom 17a of the recess 17) on the surface 10b side and the sealing portion surface 30a on the second main surface 10b side of the first sealing portion 30 are the metal second sealing portion 40. It is covered with.

On the first main surface 10a, in a plan view (viewed from the Z-axis direction), the planar shapes of the first sealing portion 30, the sealing hole 14, and the recess 17 are rectangular as shown in FIG. is there. In the electronic device 1 according to the present embodiment, a form in which the plane shape of the first sealing portion 30, the sealing hole 14, and the recess 17 is rectangular is exemplified, but the present invention is not limited to this, and is not limited to a polygonal shape. It may be circular or oval. Further, the embodiment in which the first sealing portion 30, the sealing hole 14, and the recess 17 that overlap each other are formed at one place is illustrated, but the present invention is not limited to this, and a plurality of sealing portions 30 may be formed.

The material constituting the first sealing portion 30 is preferably aluminum oxide, and the first sealing portion 30 is formed by sputtering aluminum oxide. Therefore, a porous aluminum oxide sputtered film having a large number of pores can be easily formed. Since the first sealing portion 30 is composed of a large number of pores, the pressure in the accommodation space S and the pressure outside the accommodation space S can be made the same. For example, the electronic device 1 has a reduced pressure atmosphere. By forming the second sealing portion 40 in the film, the accommodation space S can be hermetically sealed in a reduced pressure atmosphere. Further, the first sealing portion 30 is formed by intricately connecting pores leading to the accommodation space S. Therefore, during the film formation of the second sealing portion 40, the particles of the second sealing portion adhere to a large number of pores constituting the first sealing portion 30, so that the particles of the second sealing portion 30 are attached. It is possible to prevent particles from entering the containment space.

The material constituting the second sealing portion 40 is preferably a metal film or a metal oxide film. The metal film is, for example, a metal such as Au, Ag, Cu, Al, Pt, and the metal oxide film is, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), In ₃ O ₃ , SnO ₂ , It is preferable that an oxide-based conductive material such as Sb-containing SnO _{2 or Al-containing ZnO is used.} Since the second sealing portion 40 is a metal film or a metal oxide film, a dense film can be easily formed. Therefore, the dense film of the second sealing portion 40 enters the pores scattered on the sealing portion surface 30a of the first sealing portion 30 in the sealing hole 14, and the first sealing portion 30 is thin. The accommodation space S can be hermetically sealed by closing the holes and then stacking the second sealing portion 40 on the sealing portion surface 30a to close the sealing holes 14.

As described above, in the electronic device 1 according to the first embodiment, the accommodating space S composed of the element substrate 10 and the lid 20 is provided with the sealing hole 14 provided in the element substrate 10 from the accommodating space S side. Airtight sealing is performed by covering with a porous first sealing portion 30 and covering the sealing portion surface 30a on the sealing hole 14 side of the first sealing portion 30 with a metal second sealing portion 40. can do. Since the first sealing portion 30 that closes the sealing hole 14 from the accommodation space S side is porous, the second sealing portion 40 of the metal passes through the inside of the first sealing portion 30 and is accommodated. The space S cannot be reached. That is, the first sealing portion 30 is composed of a large number of pores in which the first sealing portion 30 is intricately connected. Therefore, during the film formation of the second sealing portion 40, the particles of the second sealing portion adhere to a large number of pores constituting the first sealing portion 30, so that the particles may enter the accommodation space S. Absent. Therefore, when the accommodation space S is hermetically sealed, it is possible to reduce the particles of the second sealing portion 40 from adhering to the element portion 13 and deteriorating the characteristics of the element portion 13, and to provide stable characteristics. The electronic device 1 to have can be obtained.

Further, since the first sealing portion 30 is made of aluminum oxide, a porous aluminum oxide sputtered film can be easily formed by sputtering aluminum oxide. Further, a vacuum film forming method other than sputtering may be appropriately used, and the material to be used may be preferably selected.

Further, since the second sealing portion 40 is a metal film or a metal oxide film, a dense film can be easily formed, and the accommodation space S can be maintained with high airtightness.

[Manufacturing method of electronic devices]
Next, the manufacturing method of the electronic device 1 according to the first embodiment will be described with reference to FIGS. 4 to 10.
FIG. 4 is a flowchart showing a manufacturing method of the electronic device 1 according to the first embodiment, and FIGS. 5 to 10 are cross-sectional views showing a manufacturing process of the electronic device 1 according to the first embodiment.

[Board preparation process]
First, as a substrate preparation step (S1), the element substrate 10 on which the element portion 13 is formed is prepared as shown in FIG. 5, using the SOI substrate as the substrate material M (not shown). On the element substrate 10, the element portion 13 is formed in the element forming layer 11, and the base cavity 16 is formed in the base portion 12 of the forming region of the element portion 13.

[First sealing portion forming step]
The first sealing portion forming step (S2) is executed on the element substrate 10 prepared by the substrate preparation step (S1). In the first sealing portion forming step (S2), as shown in FIG. 6, a planar porous first sealing hole is surrounded so as to surround the sealing hole formed in the sealing hole forming step (S5) described later. The sealing portion 30 is formed. For the first sealing portion 30, porous aluminum oxide or the like is preferably used. The first sealing portion 30 is formed into a predetermined shape by using a resist mask patterned and formed by a photolithography method or the like after a film of aluminum oxide is formed on the first main surface 10a by a sputtering method. To.

[Cover joining process]
In the lid joining step (S3), the joining surface 20a of the lid 20 is arranged on the first main surface 10a of the element substrate 10, and the lid 20 is joined to the first main surface 10a of the element substrate 10. In this example, the lid portion 20 exemplifies the case where a glass lid portion is used, but the lid portion 20 is not limited to this, and may be, for example, ceramics, metal, or the like.

As shown in FIG. 7, the lid portion 20 has a lid portion cavity 21 on one side, and the lid portion 20 is arranged so that the lid portion cavity 21 faces the element substrate 10 and is joined to the element substrate 10. The lid cavity 21 and the base cavity 16 of the base 12 form a storage space S for accommodating the element portion 13.

The lid 20 and the element substrate 10 are joined by using the joint surface 20a of the lid 20 and the first main surface 10a of the element substrate 10, for example, borosilicate glass for the lid 20, and mainly silicon. A method of anodic bonding the element substrate 10 as a component, or fusion bonding between the bonding surface 20a of the lid portion 20 and the first main surface 10a of the element substrate 10 via a low melting point glass powder. A method of allowing the device to be used is preferably used.

[Recess formation process]
In the recess forming step (S4), as shown in FIG. 8, the first sealing portion 30 of the element substrate 10 in a plan view (viewed from the Z-axis direction) from the direction in which the element substrate 10 and the lid portion 20 overlap each other. The silicon forming the base 12 is removed by etching up to the element forming layer 11 in the forming region of the element substrate 10, and the element is opened on the second main surface 10b side opposite to the first main surface 10a of the element substrate 10 to form the element. A recess 17 forming the membrane portion 15 made of the substrate is formed. By forming the recess 17, the membrane portion 15 is formed by the element forming layer 11, and the second surface 15b of the membrane portion 15 appears on the bottom 17a of the recess 17.

[Sealing hole forming process]
In the sealing hole forming step (S5), as shown in FIG. 9, in a plan view (viewed from the Z-axis direction), the element forming layer 11 in the region where the first sealing portion 30 and the recess 17 overlap is formed. Silicon oxide and silicon to be removed are removed by etching up to the first sealing portion 30, and a sealing hole 14 is formed. That is, a sealing hole 14 is formed in the membrane portion 15 by etching and removing a part of the second surface 15b (bottom portion 17a of the recess 17) of the membrane portion 15.

[Sealing process]
Next, a sealing step (S6) for maintaining the spatial environment of the accommodation space S in a predetermined environment is executed. In the sealing step (S6), the accommodating space S is interposed between the accommodating space S and the outside of the accommodating space S, and the porous first sealing portion 30 and the sealing hole 14. The gas in the internal space of the above, for example, air, is evacuated, and the accommodation space S is maintained in a reduced pressure state.

After that, as shown in FIG. 10, in the sealing step (S6), the second main surface 10b side is covered so as to cover the sealing hole 14 while maintaining the reduced pressure atmosphere state which is the desired space environment of the accommodation space S. A second sealing portion 40 is formed from the above, and the accommodation space S is hermetically sealed to obtain the electronic device 1 according to the first embodiment. Specifically, the inside of the accommodation space S is set to a reduced pressure atmosphere, and the second surface 15b on the second main surface 10b side of the membrane portion 15 and the first sealing formed on the membrane portion 15 are formed. The accommodation space S is airtightly sealed by covering the sealing portion surface 30a of the portion 30 with the second sealing portion 40 formed by the sputtering method.

Here, the second sealing portion 40 is preferably a metal film or a metal oxide film. The metal film is, for example, a metal such as Au, Ag, Cu, Al, Pt, and the metal oxide film is, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), In ₃ O ₃ , SnO ₂ , It is preferable that an oxide-based conductive material such as Sb-containing SnO _{2 or Al-containing ZnO is used.}

By the above steps, the electronic device 1 having high airtightness can be manufactured.

As described above, in the electronic device 1 according to the first embodiment, the porous first sealing portion 30 is formed on the element substrate 10 (SOI substrate) on which the element portion 13 is formed, and the lid portion 20 is joined. After that, a sealing hole 14 is formed at a position overlapping the first sealing portion 30 of the element substrate 10, and the sealing hole 14 is covered with the second sealing portion 40 to form the element substrate 10 and the lid portion 20. The accommodation space S in which the element unit 13 is accommodated can be hermetically sealed. Since the first sealing portion 30 is porous, when the sealing hole 14 is hermetically sealed by the second sealing portion 40 of the metal, the second sealing portion 40 of the metal is first. It cannot reach the accommodation space S through the inside of the sealing portion 30 of the above. That is, since the first sealing portion 30 is composed of a large number of pores, it is difficult to form pores that linearly communicate with the accommodation space S. Therefore, since the second sealing portion 40 of the metal adheres to a large number of pores constituting the first sealing portion 30 during the film formation, it does not enter the accommodation space S. Therefore, when the accommodation space S is hermetically sealed, it is possible to reduce that the second sealing portion 40 adheres to the element portion 13 and the characteristics of the element portion 13 are deteriorated, and the electrons having stable characteristics can be reduced. Device 1 can be manufactured.

<Second Embodiment>
[Structure of electronic device]
Next, the electronic device 1a according to the second embodiment will be described with reference to FIG.
FIG. 11 is a cross-sectional view showing the structure of the electronic device 1a according to the second embodiment. The electronic device 1a according to the second embodiment has a different form of the second sealing portion 40 provided in the electronic device 1 according to the first embodiment, and other components are the same. Therefore, in the description of the electronic device 1a according to the second embodiment, the same components as those of the electronic device 1 according to the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 11, the electronic device 1a according to the second embodiment is formed with a second sealing portion 40a for airtightly sealing the sealing hole 14 provided in the membrane portion 15. The second sealing portion 40a is formed by extending the conductive film 50 formed on the second main surface 10b side of the element substrate 10 to the recess 17 of the base portion 12. That is, the second sealing portion 40a and the conductive film 50 are electrically connected and can be made of the same material.
The conductive film 50 formed on the second main surface 10b side is for shielding noise from the mounting substrate when the second main surface 10b of the element substrate 10 is mounted facing the mounting substrate. Therefore, the influence of external noise on the element unit 13 accommodated in the accommodation space S can be reduced.

The material constituting the conductive film 50 is preferably a metal film, and for example, it is preferable that a metal such as Au, Ag, Cu, Al, or Pt is formed by a sputtering method.

As described above, in the electronic device 1a according to the second embodiment, the second sealing portion 40a for airtightly sealing the sealing hole 14 is formed so as to extend from the conductive film 50. Therefore, the second sealing portion 40a that airtightly seals the accommodation space S can be formed at the same time as the formation of the conductive film 50 arranged on the second main surface 10b, and high productivity can be obtained. ..

[Manufacturing method of electronic devices]
Next, a method of manufacturing the electronic device 1a according to the second embodiment will be described with reference to FIG.
FIG. 12 is a flowchart showing a manufacturing method of the electronic device 1a according to the second embodiment. The method for manufacturing the electronic device 1a according to the second embodiment is different from the sealing step (S6) in the method for manufacturing the electronic device 1 according to the first embodiment. Therefore, the description of the substrate preparation step (S1) to the sealing hole forming step (S5), which are the same manufacturing methods as in the first embodiment, will be omitted.

[Sealing process]
As shown in FIG. 12, the sealing step (S60) in the method for manufacturing the electronic device 1a as the second embodiment includes a conductive film forming step (S61).

[Conducting film forming process]
In the conductive film forming step (S61), the conductive film 50, for example, a metal such as Au, Ag, Cu, Al, Pt, is sputtered from the second main surface 10b side of the element substrate 10, and the second main surface of the element substrate 10 is formed. By laminating on the main surface 10b, the second surface 15b of the membrane portion 15, and the sealing portion surface 30a of the first sealing portion 30, the sealing holes 14 provided in the membrane portion 15 are aired. A second sealing portion 40a to be tightly sealed can be formed.

As described above, in the manufacturing method of the electronic device 1a according to the second embodiment, in the manufacturing method of the sealing step (S60), the conductive film forming step (S61) for forming the conductive film 50 is performed to form the element substrate 10. When the conductive film 50 is formed on the main surface 10b of 2, the second sealing portion 40a that covers the sealing hole 14 provided in the membrane portion 15 can be formed at the same time. Therefore, the electronic device 1a having high airtightness can be manufactured with high productivity.

<Third Embodiment>
[Structure of electronic device]
Next, the electronic device 1b according to the third embodiment will be described with reference to FIG.
FIG. 13 is a cross-sectional view showing the structure of the electronic device 1b according to the third embodiment. The electronic device 1b according to the third embodiment has a different form of the recess 17 provided in the electronic device 1 according to the first embodiment, and other components are the same. Therefore, in the description of the electronic device 1b according to the third embodiment, the same components as those of the electronic device 1 according to the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 13, the electronic device 1b according to the third embodiment has a tapered portion in which the recess 17b provided in the element substrate 10 extends from the first main surface 10a side toward the second main surface 10b. Have. In the present embodiment, the tapered portion is provided in the recess 17b, but the tapered portion may be provided in the middle of the recess 17b. Further, it may be provided in the sealing hole 14.

As described above, in the electronic device 1b according to the third embodiment, since the recess 17b has a tapered portion extending toward the second main surface 10b, the second sealing is performed from the second main surface 10b side. When the sealing portion 40 is formed and the sealing hole 14 provided in the membrane portion 15 is airtightly sealed, the second sealing portion 40 can be easily reached to the sealing hole 14 and has high airtightness. The electronic device 1b can be obtained.

1,1a, 1b ... Electronic device, 10 ... Element substrate, 10a ... First main surface, 10b ... Second main surface, 11 ... Element forming layer, 12 ... Base, 13 ... Element part, 14 ... Sealing hole , 15 ... Membrane part, 15a ... First surface, 15b ... Second surface, 16 ... Base cavity, 17, 17b ... Recessed part, 17a ... Bottom, 20 ... Lid part, 20a ... Joint surface, 21 ... Lid part Cavity, 30 ... first sealing portion, 30a ... sealing portion surface, 40, 40a ... second sealing portion, 50 ... conductive film, S ... accommodating space.

Claims (7)

An element substrate composed of an SOI substrate and a lid portion joined to the first main surface of the element substrate are provided, and the element portion is provided in a storage space formed between the element substrate and the lid portion. Is an electronic device that houses
The element substrate includes an element forming layer including the first main surface and the element portion, and a base including a second main surface opposite to the first main surface.
The base portion is provided with a cavity constituting the accommodation space in a region overlapping the element portion in a plan view.
The element substrate is disposed between the first of said lid portion is bonded portion of the principal surface in plan view and said cavity includes a front Symbol opening the second main surface side of the base Rutotomoni has a recess the bottom of the first main surface side, and a configured membrane portion between said bottom portion said first main surface,
The membrane portion includes a sealing hole that penetrates the membrane portion.
The first surface of the membrane portion, which is the first main surface side, and the sealing hole are covered with a porous first sealing portion.
The second surface (bottom of the recess) of the membrane portion on the second main surface side and the sealing portion surface of the first sealing portion on the second main surface side are second sealed. Covered with a stop,
An electronic device characterized by that. The electronic device according to claim 1, wherein the first sealing portion is a sputtered film of aluminum oxide. The electronic device according to claim 1 or 2, wherein the second sealing portion is a metal film. The electronic device according to claim 1 or 2, wherein the second sealing portion is a metal oxide film. The electronic device according to claim 3, wherein the metal film extends from a conductive film disposed on the second main surface. The substrate preparation process for preparing the SOI substrate on which the element part is formed, and
A first sealing portion forming step of forming a porous first sealing portion on the first main surface of the SOI substrate on the side where the element portion is formed, and a step of forming the first sealing portion.
A lid joining step of joining a lid portion constituting an accommodation space of the element portion to the first main surface of the SOI substrate, and a lid joining step.
In a plan view, an opening is made in the formation region of the first sealing portion of the SOI substrate on the side of the second main surface opposite to the first main surface of the SOI substrate, and the membrane portion made of the SOI substrate is formed. The recess forming step of forming the constituent recesses and the recess forming process
A sealing hole forming step of removing a part of the bottom portion of the recess from the second main surface side opposite to the first main surface of the SOI substrate to form a sealing hole in the membrane portion.
A sealing step of setting the accommodating space as a predetermined space environment and airtightly sealing the sealing hole with a second sealing portion of metal is included.
A method of manufacturing an electronic device. The method for manufacturing an electronic device according to claim 6 , wherein the sealing step includes a conductive film forming step of forming a conductive film on the second main surface side.

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