JP2007216309A - Electronic device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve new structure and manufacturing method, simply performing a sealing process of a functional structure, and reducing the manufacturing cost. <P>SOLUTION: This electronic device 10 includes: a board 1; a functional structure 3X constituting a functional element formed on the board; and a covering structure for defining a cavity part C where the functional structure is disposed, wherein the covering structure includes: a covering body disposed to cover at least the upper part of the cavity part, the covering body includes: a first covering layer 5B disposed on the lower layer; and a second covering layer 7B disposed on the upper layer to the first covering layer, and the first covering layer and the second covering layer are provided with opening areas 5Ba, 7Ba in a part of range where the respective covering bodies cover the cavity part from above, and overlap the other opening areas in plane. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an electronic device and a method for manufacturing the same, and in particular, a MEMS (micro electro mechanical system).
The present invention relates to a structure and a manufacturing method suitable for application to an electronic device including an element.

In recent years, resonators, high frequency filters, micro actuators, pressure sensors, gyro sensors,
A technology for realizing an acceleration sensor or the like with a micro electro mechanical systems (MEMS) element has been developed, and various products have already been put into practical use. The MEMS element is composed of a micro structure formed by applying a semiconductor process technology. To configure the MEMS element to be operable and protect the MEMS element, the MEMS structure is disposed in the cavity, and the cavity Need to be closed. In particular, if dust adheres to the MEMS structure, oxidation, moisture absorption, or the like occurs, there is a risk of malfunction, and in the element where the gas resistance affects the operation, it is necessary to exclude the gas around the MEMS element. The cavity is preferably sealed.

As a method for closing the cavity in which the MEMS structure is disposed, for example, a MEM is formed on a substrate.
After forming the S structure, the counter substrate made of a glass substrate or the like and the above substrate are joined directly or via an O-ring or the like, and the cavity where the MEMS structure is disposed is sealed by the counter substrate. (For example, refer to Patent Document 1 below).
JP 2005-297180 A

However, in the above-described MEMS structure sealing method, it is necessary to use a counter substrate for sealing, and a special process for bonding the counter substrate onto the substrate is necessary. There is a problem that the advantage of the MEMS element that can be formed by the semiconductor manufacturing technology is lost and the manufacturing cost increases.

In addition, the above-described sealing method is practically performed in units of wafers, but after that, it is necessary to divide a thick structure composed of a substrate and a counter substrate bonded to each other by dicing or the like. There is a problem that it takes time and effort. Note that performing the above-described sealing method in units of chips makes it very difficult to perform the division process without damaging the MEMS structure in the step before the MEMS structure is sealed. However, since it is necessary to carry out a sealing process for each of a large number of chips after that, it is not practical in terms of manufacturing technology.

Furthermore, the above problems are not limited to the MEMS structure, but also exist in electronic devices including various functional elements such as other crystal resonators, SAW elements, and gyro sensors that are not included in the MEMS. .

Therefore, the present invention solves the above-described problems, and the problem is that an electronic device including a functional element can easily perform a sealing process of a functional structure and can reduce manufacturing costs. It is to realize a novel structure and manufacturing method.

In view of such circumstances, the electronic device of the present invention includes a substrate, a functional structure that forms a functional element formed on the substrate, and a covering structure that defines a cavity in which the functional structure is disposed. The covering structure includes a covering body disposed so as to cover at least the upper part of the cavity, and the covering body includes a first covering layer disposed in a lower layer, and the first covering layer. A second covering layer disposed on the upper layer with respect to the covering layer, wherein the first covering layer and the second covering layer are ranges in which the covering body covers the cavity from above. Are provided with an opening region in a part thereof, and each of them overlaps with the other opening region in a planar manner.

According to this invention, the covering body includes the first covering layer and the second covering layer that are each provided with an opening region in a part of a range that covers the cavity from above, and the first covering layer includes By configuring the covering layer and the second covering layer so as to overlap each other with the entire other opening region,
The cavity is covered by the covering from above. At this time, in a state in which the covering body has the first covering layer and the second covering layer, and the first covering layer and the second covering layer are separated from each other in the vertical direction, It is possible to form a cavity by removing the lower layer structure between one coating layer and the second coating layer, or to exhaust the cavity and fill the cavity with gas. become. Therefore, it is not necessary to attach a counter substrate for sealing, so that a special process is not required, and thus it is possible to manufacture with a simpler process than before, so that the manufacturing cost can be reduced.

In this invention, it is preferable that at least any one of the said 1st coating layer and the said 2nd coating layer is supported via the support beam part which can deform | transform in an up-down direction. According to this, since at least one of the first coating layer and the second coating layer is supported via the support beam portion that can be deformed in the vertical direction, the first coating layer and the second coating layer are supported. It is easy to seal the cavity portion by initially setting the covering layers apart from each other and joining or bonding the two layers from this state.

In the present invention, the first coating layer and the second coating layer are in contact with each other, the first opening region is closed with the second coating layer, and the second opening region is the first coating layer. Preferably, it is closed with one coating layer. According to this, since the first covering layer and the second covering layer are in contact with each other and the respective open regions are closed with each other, the cavity can be reliably closed by the covering.

In this case, it is preferable that the first coating layer and the second coating layer are joined. According to this, since the closed state of the covering can be maintained, the cavity can be reliably closed. Here, the first coating layer and the second coating layer may be directly bonded, or may be bonded via an adhesive layer or the like.

In the present invention, it is preferable that a plurality of the functional structures and a plurality of the cavity portions in which the functional structures are respectively disposed are provided on the substrate. By providing a plurality of functional structures and cavities, the sealing process can be performed efficiently.

In the present invention, the coating structure is formed by laminating a plurality of layers around the cavity, and each of the first coating layer and the second coating layer is the same as at least one of the plurality of layers. It is preferable that the material is formed in the same layer. According to this, the first covering layer and the second covering layer are formed of the same material and in the same layer as at least one of the plurality of layers formed around the cavity, respectively. Since the layers can be formed simultaneously with other structures in the covering structure, it is not necessary to provide a dedicated manufacturing process for forming both layers, so that the manufacturing cost can be further reduced.

In this case, the at least one layer is preferably a conductor layer. According to this,
The conductor layer is inevitably formed as a wiring or electrode in the covering structure,
Since patterning is easy and the etching method used for removing the insulator is highly selective with the insulator, it is convenient both when forming both layers and when removing the lower layer structure via both layers. It becomes the composition.

In the present invention, the substrate is preferably a semiconductor substrate. According to this, since the semiconductor circuit and the functional element can be integrally formed by using the semiconductor substrate, an electronic circuit device having a complicated circuit structure can be easily realized. In this case, the functional element is M
An EMS element (micro-electromechanical structure) can be integrally manufactured using a general semiconductor manufacturing process, so that it is more preferable in terms of increasing the manufacturing efficiency of an electronic device including a MEMS element and reducing the manufacturing cost. It becomes.

Next, a method for manufacturing an electronic device according to the present invention includes a substrate, a functional structure that forms a functional element formed on the substrate, and a covering structure that defines a cavity in which the functional structure is disposed. A step of forming a first covering layer provided above the functional structure and having a first opening region, and disposed above the functional structure, A second covering layer having a second opening area that covers the first opening area in a plane and is covered in a plane by the first covering layer is separated from the upper layer of the first covering layer. Bonding the first covering layer and the second covering layer, closing the first opening area with the second covering layer, and closing the second opening area with the second covering area. And a step of closing with one coating layer.

Another method of manufacturing an electronic device according to the present invention includes a substrate, a functional structure that forms a functional element formed on the substrate, and a covering structure that defines a cavity in which the functional structure is disposed. And a step of forming the functional structure on the substrate, and forming a first coating layer disposed above the functional structure and having a first opening region. And a step of arranging the first opening region in a plan view, the first opening region being disposed above the functional structure,
Forming a second covering layer having a second opening area, which is planarly covered by the covering layer, on the upper layer of the first covering layer, and forming the first opening area and the second opening area. And forming the cavity in which the functional element is disposed by removing the covering structure around the functional structure through the first covering layer and the second covering layer. Bonding the first covering layer and the second covering layer to close the first opening area with the second covering layer and to close the second opening area to the first opening area. And a step of closing with the covering layer.

In the present invention, it should be interposed between the first coating layer and the second coating layer between the step of forming the first coating layer and the step of forming the second coating layer. It is preferable to further comprise a step of forming an interlayer sacrificial layer and a step of removing the interlayer insulating layer.

In the present invention, the step of joining the first coating layer and the second coating layer includes the first coating layer.
The first coating layer and the second coating layer are brought into contact with each other by electrostatic attraction generated by applying a potential difference between the coating layer of the second coating layer and the second coating layer. First
Preferably, the first covering layer and the second covering layer are welded by a current flowing between the covering layer and the second covering layer.

Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1 to 12
These are the general | schematic process drawings which show the manufacturing method of the electronic device which concerns on this invention. 4 to 12 also show partial plan views showing ranges indicated by arrows in the longitudinal sectional views. First, a method for manufacturing an electronic device according to the present invention will be described.

First, a substrate 1 made of a semiconductor substrate or the like shown in FIG. 1 is prepared. The substrate 1 is most preferably a semiconductor substrate such as a silicon substrate, but various substrates such as a ceramic substrate, a glass substrate, a sapphire substrate, a diamond substrate, and a synthetic resin substrate can be used. When a semiconductor substrate is used, a predetermined semiconductor integrated circuit (not shown) can be built in the substrate 1 in advance. In the manufacturing method of this embodiment, an appropriate impurity region (
A semiconductor substrate provided with a not shown) is used. Also, a manufacturing method is set so that an appropriate wiring structure is formed on the semiconductor substrate, and an electronic device is formed by a CMOS process as a whole.

In the present embodiment, the sacrificial layer 2 is formed on the surface of the substrate 1. The sacrificial layer 2 can be composed of, for example, a silicon oxide film, a PSG (phosphorus doped glass) film, or the like, and is formed by a CVD method, a sputtering method, or the like. In the illustrated example, a MEMS to be described later is placed at an appropriate position of the sacrificial layer 2.
The opening 2a for forming the support portion of the structure is formed by an appropriate patterning process such as a method of performing etching using a patterning mask formed by a photolithography method or the like.

Next, as shown in FIG. 2, a functional layer 3 made of a conductive silicon film or the like is formed on the sacrificial layer 2. The functional layer 3 is connected to the substrate 1 (for example, a lower electrode (not shown) formed on the substrate 1) through the opening 2a formed as described above. The functional layer 3 is formed by a sputtering method, a CVD method, or the like. Then, by patterning the functional layer 3 by an appropriate patterning method, a MEMS structure 3X is formed as shown in FIG.

In the illustrated example, a diaphragm-shaped MEMS structure 3X having a support portion corresponding to the opening 2a of the sacrificial layer 2 at the center lower portion is provided, but the counter electrode and the like are not shown. Also,
The illustrated example schematically shows a MEMS structure, and does not accurately represent an actual structure. As the MEMS structure, a movable portion having various planar patterns such as a comb shape, a beam shape, and a disk shape can be formed. In addition, an element configured as an element having an arbitrary function such as an element used as a vibrator, an actuator, or a sensor can be formed.

In addition to the MEMS structure 3X, a functional structure for configuring various functional elements such as a crystal resonator, a SAW (surface acoustic wave) element, an acceleration sensor, and a gyroscope other than the MEMS may be used. . That is, the functional element of the present invention may be any device as long as it has a functional structure that can be disposed in the cavity. Here, the functional structure may constitute only a part of the functional element.

Next, as shown in FIG. 4, an insulating film 4 made of an insulator such as silicon oxide is formed on the MEMS structure 3X, and a conductive layer 5 such as aluminum is formed thereon. Then, the conductive layer 5 is patterned to form a wiring layer 5A and a first covering layer 5B as shown in FIG. An appropriate covering structure can be formed by repeatedly laminating a plurality of such insulating films 4 and wiring layers 5A. This covering structure is formed in the same manner as a normal CMOS process. In addition, the number of stacked layers in which the insulating film 4 and the wiring layer 5A are repeatedly formed is appropriately configured as necessary. For example, in an actual CMOS process, more wiring layers may be stacked via an insulating film.

The first covering layer 5B is formed above the MEMS structure 3X. A first opening region 5Ba is provided in the first covering layer 5B. In the illustrated example, the first opening region 5Ba is the first
The coating layer 5B is provided at the center (position directly above the MEMS structure 3X). Since the first covering layer 5B is formed in the same process as the wiring layer 5A, it can be dealt with only by changing the formation pattern of the patterning process, and there is no need to change the number of processes or the contents of the processes.

The first covering layer 5B is made of a conductor as described above, and is configured so that a potential can be supplied from the outside by being electrically connected to the wiring portion 5Bc. Thereafter, as shown in FIG. 6, an insulating film 6 is formed on the wiring layer 5A and the first covering layer 5B. Here, the insulating film 6 is provided with a through hole 6a exposing a part of the wiring layer 5A.

Next, as shown in FIG. 7, a conductive layer 7 is formed on the insulating film 6 using a conductor such as aluminum. Then, by patterning the conductive layer 7, as shown in FIG. 8, the second covering layer 7B is formed together with the wiring layer or the connection pad 7A. The second coating layer 7B is formed above the MEMS structure 3X and the first coating layer 5B. The second coating layer 7B is
In the plane range where either one of the first coating layer 5B and the second coating layer 7B is arranged,
This is accompanied by a second opening region 7Ba that entirely overlaps the formation range of the first covering layer 5B in a plane.
The second coating layer 7B is configured to overlap the entire first opening region 5Ba provided in the first coating layer 5B in a planar manner.

The second covering layer 7B is configured to include a second opening region 7Ba on the outer peripheral portion that overlaps the first covering layer 5B, and the covering portion 7Bx that overlaps the first opening region 5Ba in plan view. ,
A support beam portion 7By for supporting the covering portion 7Bx. That is, the covering portion 7
A portion other than the support beam portion 7By around the Bx is the second opening region 7Ba. The support beam portion 7By is configured to be deformable so as to support the covering portion 7Bx so as to be movable up and down. In this state, the first coating layer 5 </ b> B and the second coating layer 7 </ b> B are separated from each other in the vertical direction via the insulating film 6.

The second covering layer 7B is made of a conductor, and the supporting beam portion 7By extends as a wiring portion as it is, and is configured so that a potential can be supplied from the outside.

Next, as shown in FIG. 9, a protective film 8 made of silicon oxide, silicon nitride, resin material, or the like is formed on the insulating film 6, the wiring layer 7A, and the second coating layer 7B. As the protective film 8, a surface protective film (passivation film) of a semiconductor device can be used. However, it is desirable to form the protective film 8 with a material that can withstand an etching solution used in a release process described later (usually silicon nitride or a resin material is preferable).

Thereafter, as shown in FIG. 10, the protective film 8 is partially removed by a dry etching method or the like, and an opening 8a is formed to expose a part of the wiring layer or the connection pad 7A so that the connection pad can be connected. And an opening 8b is formed to expose the surfaces of the first coating layer 5B and the second coating layer 7B (opening step). That is, in this step, the protective film 8 is partially removed, so that the second coating layer 7B is first exposed, and then the first coating layer 5B is exposed in the second opening region 7Ba.

At this time, if the etching method is isotropic etching, the insulating film 6 between the first coating layer 5B and the second coating layer 7B is also removed. Coating layer 5B
And the insulating film 6 interposed between the second coating layer 7B is left. The remaining insulating film 6 may be separately removed by isotropic etching. Thus, by removing the insulating film 6 between the first coating layer 5B and the second coating layer 7B during the opening process of the protective film 8, the lower layer structure of the first coating layer 5B is obtained. On the other hand, the second opening region 7Ba, the first opening region 5Ba, and
Since the etching liquid easily enters through the space between the first coating layer 5B and the second coating layer 7B, the removing action in the release process described below can be enhanced. In this release step, the insulating film 6 interposed between the first coating layer 5B and the second coating layer 7B may be removed.

Next, the second opening region 7Ba, the first coating layer 5B, and the second coating layer 7 of the second coating layer 7B.
An etching solution (such as an aqueous solution containing hydrofluoric acid) acts through the space between B (the portion where the insulating film 6 was present) and the first opening region 5Ba of the first coating layer 5B. As shown in FIG. 11, the insulating film 4 and the sacrificial layer 2 below the first covering layer 7B are removed (release process). As a result, a predetermined part of the MEMS structure 3X is released from the substrate 1, and a structure capable of realizing an original operation (function) is obtained. At this time, the MEMS structure 3X has a cavity C.
The first cover layer 5B and the second cover layer 7B cover the cavity C from above.

Thereafter, in the cavity C, the second opening region 7Ba of the second coating layer 7B, the space between the first coating layer 5B and the second coating layer 7B (the portion where the insulating film 6 was present), And the 1st coating layer 5B
The first opening region 5Ba is cleaned by an appropriate method such as cleaning. Then, as necessary, processing such as decompression in the cavity C, evacuation, and replacement with an inert gas such as nitrogen gas is performed.
However, such processing is not essential and may be omitted if unnecessary.

Finally, a predetermined potential difference is applied between the first coating layer 5B and the second coating layer 7B, whereby the electrostatic attraction force that the coating portion 7Bx of the second coating layer 7B receives from the first coating layer 5B. As a result, the second coating layer 7B comes into contact with the first coating layer 5B as shown in FIG. If the contact state is maintained with some adhesion force such as van der Waals force even if the potential difference is removed, it can be left as it is.

If the above contact state cannot be maintained, for example, the first coating layer 5B and the second coating layer 7B are welded by supplying a current between both layers by applying the potential difference or a potential difference different from the potential difference. Can be joined. Moreover, you may adhere | attach the 1st coating layer 5B and the 2nd coating layer 7B with an adhesive agent. The above is the joining process of the first coating layer 5B and the second coating layer 7B. Here, the bonded first covering layer 5B and the second covering layer 7B are formed by the MEMS structure 3.
A covering 10P that covers the cavity C where X is disposed from above is configured.

For example, when the first coating layer 5B and the second coating layer 7B are made of aluminum, it is preferable to apply a potential difference of 10 volts or more between the two layers in order to bring them into contact with each other. Further, when both layers are joined, they can be welded (melted and fixed) with a current of about several mA. Note that the above-described process of applying a potential difference or passing a current between the first coating layer 5B and the second coating layer 7B can also be performed in the electrical inspection process of the electronic device 10. For example, the potential difference or current can be applied using an inspection tester.

Instead of the above-described joining step, the second coating layer 7B may be brought into contact with the first coating layer 5B by mechanically pressing from above. Further, the first coating layer 5B and the second coating layer 7
B is left in a state of being spaced apart vertically, and the sealing agent is poured into the opening 8b to form the first coating layer 5B.
And the second coating layer 7B may be sealed. Examples of such a sealant include synthetic resin materials such as polyimide resin and silicone rubber, and silicate materials such as SOG. An ultraviolet curable resin or a thermosetting resin may be used.

In the illustrated example, the cavity C in which the MEMS structure 3X is disposed has a covering structure (sacrificial layer 2, insulating film 4, wiring layer 5A, first covering layer 5B, insulating film 6) formed on the substrate 1. , Wiring layer 7A
The second coating layer 7B and the protective film 8 are included. ), But when there is no need (for example, a case where large dust does not enter the cavity C and air may enter), the cavity C is not completely sealed. Also good. However, it is preferable that the first coating layer 5B and the second coating layer 7B are joined or sealed in some form even if partially.

In the electronic device 10 configured as described above, since the cavity C in which the MEMS structure 3X is disposed is covered with the covering 10P, dust, water, and other things enter the cavity C from the outside. Can be prevented. Further, since the cavity C is sealed with the covering body 10P, the cavity C can be in a reduced pressure state (vacuum state).
The hindrance to the operation of the S structure 3X can be eliminated. Furthermore, since it is possible to fill the cavity C with an inert gas such as nitrogen gas, it is possible to prevent the MEMS structure 3X from being deteriorated due to oxidation, moisture absorption, or the like.

FIG. 13 is a longitudinal sectional view and a partial plan view showing an electronic device 10 ′ according to another embodiment. This embodiment has basically the same basic structure as the electronic device 10 described above, but a plurality of first opening regions 5Ba 'are provided in the first coating layer 5B'. The second coating layer 7
B ′ is similar to the previous embodiment in that it has a support beam portion 7By ′ that supports the covering portion 7Bx ′ so as to be movable up and down, but other than the second opening region 7Ba ′ around the covering portion 7Bx ′. The difference is that a plurality of second opening regions 7Bb 'are formed in the covering portion 7Bx'.

The first opening region 5Ba ′ associated with the first coating layer 5B ′ is formed at a position that does not overlap the second opening regions 7Ba ′ and 7Bb ′ associated with the second coating layer 7B ′. Yes.
Therefore, the point which comprises the covering which covers cavity C from the upper part, and 2nd covering layer 7B
Is the same as the previous embodiment in that the first opening region 5Ba 'and the second opening regions 7Ba', 7Bb 'are closed by lowering' and descending and contacting with the first covering layer 5B '. .

As can be seen from the upper and lower partial plan views shown in FIG. 13, the second opening region 7Bb ′
May be arranged vertically and horizontally in the covering portion 7Bx ′, or may be formed in a slit shape.

FIG. 14 is a longitudinal sectional view and a partial plan view showing an electronic device 10 ″ of still another embodiment. This embodiment also basically has the same basic structure as the electronic device 10 of the previous embodiment. The first coating layer 5B ″ is provided with a coating portion 5Bx ″ and a support beam portion 5By ″ that supports the coating portion 5Bx ″, whereby the first coating layer 5B ″ is configured to be movable up and down. Instead, the second coating layer 7B ″ is also fixed to the surrounding coating structure. However, the first opening region 5Ba ″ set in the first covering layer 5B ″ all overlaps the second covering layer 7B ″ in a plan view, and the second opening provided in the second covering layer 7B ″. This is the same as the previous embodiment in that the region 7Ba ″ is configured so as to overlap with the first covering layer 5B ″ in a planar manner.

In this embodiment, the first opening region 5Ba ″ and the second opening region 7Ba ″ are closed by moving the first covering layer 5B ″ upward and bringing it into contact with the second covering layer 7B ″. The coated body is configured. Unlike the above embodiments, both the first coating layer and the second coating layer may be configured to be movable up and down.

In each of the above-described embodiments, the covering portion of the covering layer is configured to be movable up and down by providing the supporting beam portion. However, the deformation of the covering layer itself can be performed without providing such a supporting beam portion. It is also possible to contact with the other coating layer in the same manner as described above. Therefore, the first covering layer and the second covering layer may be configured so as not to have the support beam portion.

15 is a longitudinal sectional view showing a case where a plurality of electronic devices 10 are formed in one large substrate (hereinafter simply referred to as “wafer”) W unit, and FIG. 16 is a schematic perspective view of the wafer W. Wafer W is
An integral covering structure 10C provided with a plurality of sets of the MEMS structure 3X and the cavity C on the substrate 1
Finally, each cavity C is closed with the above-described covering body 10P. And
The wafer W is divided into a plurality of electronic devices 10 by dicing, a scribe break method, or the like (substrate dividing step). In the illustrated example, a state in which only one hollow portion closed by one covering body 10P is provided in one electronic device 10 is not limited to such a state, but one electronic device is provided. In FIG. 10, a plurality of cavities may be provided.

In the above process, since the cavity C in which the MEMS structure 3X is arranged is closed before the wafer W is divided, the MEMS structure 3X is not contaminated in the substrate dividing process. Further, the electronic device 10 manufactured in this way does not need to be repackaged.
For example, it can be used as a surface-mount type electronic device and can greatly contribute to downsizing.

Note that the electronic device and the manufacturing method thereof according to the present invention are not limited to the illustrated examples described above, and it is needless to say that various modifications can be made without departing from the gist of the present invention.

For example, in the above embodiment, a MEMS structure 3X that constitutes a MEMS element as a functional element such as an actuator, a resonator, or a high frequency filter is formed on a semiconductor substrate while performing a semiconductor manufacturing process similar to a CMOS process. However, the present invention is not limited to the one provided with the MEMS element, but can be applied to one provided with various functional elements other than the MEMS element such as a crystal resonator, a SAW element, an acceleration sensor, and a gyro sensor.

In the above embodiment, the semiconductor device is configured by integrating the functional element with the semiconductor integrated circuit. However, a substrate other than the semiconductor substrate may be used, or another electronic element is connected to the functional element. It does not matter.

FIG. 5 is a schematic process cross-sectional view showing the manufacturing process of the embodiment. FIG. 5 is a schematic process cross-sectional view showing the manufacturing process of the embodiment. FIG. 5 is a schematic process cross-sectional view showing the manufacturing process of the embodiment. The general | schematic process sectional drawing and the partial top view which show the manufacturing process of embodiment. The general | schematic process sectional drawing and the partial top view which show the manufacturing process of embodiment. The general | schematic process sectional drawing and the partial top view which show the manufacturing process of embodiment. The general | schematic process sectional drawing and the partial top view which show the manufacturing process of embodiment. The general | schematic process sectional drawing and the partial top view which show the manufacturing process of embodiment. The general | schematic process sectional drawing and the partial top view which show the manufacturing process of embodiment. The general | schematic process sectional drawing and the partial top view which show the manufacturing process of embodiment. The general | schematic process sectional drawing and the partial top view which show the manufacturing process of embodiment. FIG. 4 is a schematic cross-sectional view and a partial plan view showing the manufacturing process of the embodiment and the structure of the electronic device. The schematic sectional drawing and partial plan view which show the structure of the electronic device of another embodiment. FIG. 6 is a schematic cross-sectional view and a partial plan view showing the structure of an electronic device according to another embodiment. The longitudinal cross-sectional view of the electronic device manufactured by the wafer unit. The schematic perspective view of a wafer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 2 ... Sacrificial layer, 3 ... Functional layer, 3X ... MEMS structure (functional structure), 4 ... Insulating film, 5 ... Conductive layer, 5A ... Wiring layer, 5B ... 1st coating layer, 5Ba ... 1st opening area | region, 6 ... insulating film, 7 ... conductor layer, 7A ... wiring layer, 7B ... 2nd coating layer, 7Ba ... 2nd opening area | region, 8 ... protective film, 10 ... electronic device, W ... wafer 10C: Cover structure, 10P: Cover

Claims (11)

In an electronic device comprising: a substrate; a functional structure that forms a functional element formed on the substrate; and a covering structure that defines a cavity in which the functional structure is disposed.
The covering structure has a covering disposed so as to cover at least the upper part of the cavity,
The covering includes a first covering layer disposed in a lower layer and a second covering layer disposed in an upper layer with respect to the first covering layer,
Each of the first covering layer and the second covering layer includes an opening region in a part of a range in which the covering body covers the cavity from above, and overlaps the other opening region in a plane. An electronic device characterized by the above. 2. The electronic device according to claim 1, wherein at least one of the first coating layer and the second coating layer is supported via a support beam portion that is deformable in a vertical direction. The first covering layer and the second covering layer are in contact with each other, the first opening region is closed with the second covering layer, and the second opening region is the first covering layer. The electronic device according to claim 1, wherein the electronic device is closed at a closed position. The electronic device according to claim 3, wherein the first coating layer and the second coating layer are bonded to each other. 5. The plurality of functional structures and the plurality of cavities in which the functional structures are respectively disposed are provided on the substrate. 6. Electronic equipment. The covering structure is formed by laminating a plurality of layers around the cavity, and the first covering layer and the second covering layer are each made of the same material and the same layer as at least one of the plurality of layers. The electronic device according to claim 1, wherein the electronic device is formed.   The electronic device according to claim 6, wherein the at least one layer is a conductor layer. The electronic device according to claim 1, wherein the substrate is a semiconductor substrate. In a method for manufacturing an electronic device, comprising: a substrate; a functional structure that forms a functional element formed on the substrate; and a covering structure that defines a cavity in which the functional structure is disposed.
Forming a first covering layer disposed above the functional structure and having a first opening region;
A second covering layer that is disposed above the functional structure, covers the first opening area in a plane, and includes a second opening area that is covered in a plane by the first covering layer. Forming the first covering layer so as to be spaced apart from the upper layer;
The first covering layer and the second covering layer are joined, the first opening area is closed with the second covering layer, and the second opening area is closed with the first covering layer. A closing step;
A method for manufacturing an electronic device, comprising: In a method for manufacturing an electronic device, comprising: a substrate; a functional structure that forms a functional element formed on the substrate; and a covering structure that defines a cavity in which the functional structure is disposed.
Forming the functional structure on the substrate;
Forming a first covering layer disposed above the functional structure and having a first opening region;
A second covering layer that is disposed above the functional structure, covers the first opening area in a plane, and includes a second opening area that is covered in a plane by the first covering layer. Forming the first covering layer so as to be spaced apart from the upper layer;
The function is achieved by removing the first opening area, the second opening area, and the covering structure around the functional structure through the first covering layer and the second covering layer. Forming the cavity where the element is disposed;
The first covering layer and the second covering layer are joined, the first opening area is closed with the second covering layer, and the second opening area is closed with the first covering layer. A closing step;
A method for manufacturing an electronic device, comprising: The step of joining the first coating layer and the second coating layer is performed by the electrostatic attraction generated by applying a potential difference between the first coating layer and the second coating layer. The first coating layer and the second coating layer are brought into contact with each other, and the first coating layer and the second coating layer are brought into contact with each other by a current flowing between the first coating layer and the second coating layer in the contact state. 11. The method for manufacturing an electronic device according to claim 9, wherein the second coating layer is welded.

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