JP2018073967A - Semiconductor device, solid-state image pickup device and manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further improve the bonding strength when two substrates are laminated to form a structure. SOLUTION: A first substrate having a first electrode made of metal and a second substrate having a second electrode made of metal, which is bonded to the first substrate, An insulating film is formed on at least one of the bonded surfaces of the first substrate and the second substrate so as to have openings corresponding to the uplift of the metal during the heat treatment after the bonded surfaces are bonded. A semiconductor device is provided in which the first electrode and the second electrode are metal-bonded at an opening of an insulating film. This technology can be applied to a solid-state image sensor such as a CMOS image sensor, for example. [Selection diagram] Fig. 2

Description

  The present technology relates to a semiconductor device, a solid-state imaging device, and a manufacturing method, and more particularly, a semiconductor device and a solid-state imaging device that can further improve the bonding strength when two substrates are bonded to each other. And a manufacturing method.

  Conventionally, high concentration of a semiconductor device having a two-dimensional structure has been realized by introduction of a fine process and improvement of mounting density. However, high concentration of a two-dimensional structure by these has physical limitations. Therefore, in order to realize further downsizing of the semiconductor device and higher density of pixels, a semiconductor device having a three-dimensional structure has been developed.

  For example, Patent Document 1 proposes a semiconductor device having a three-dimensional structure in which two substrates are stacked and bonded together. In Patent Document 1, the dummy electrodes arranged on the bonding surfaces of the first wiring layer and the second wiring layer are bonded to each other to increase the area where metal bonding is performed, thereby firmly bonding the semiconductor members to each other. I can do it.

JP 2012-256736 A

  By the way, in a semiconductor device having a three-dimensional structure, various structures have been proposed in order to bond more firmly when two substrates are stacked and bonded, but the bonding strength may not be sufficient. Therefore, a structure that can further improve the bonding strength is desired.

  This technique is made in view of such a situation, and makes it possible to further improve the bonding strength when two substrates are bonded to each other.

  A semiconductor device according to one aspect of the present technology includes a first substrate having a first electrode formed of metal, and a substrate bonded to the first substrate, the second electrode formed of metal And at least one bonding surface of the first substrate and the second substrate according to the metal bulge during the heat treatment after the bonding of the bonding surfaces. An insulating film in which an opening is formed is formed, and the first electrode and the second electrode are a semiconductor device in which metal bonding is performed at the opening of the insulating film.

  A solid-state imaging device according to one aspect of the present technology includes a sensor substrate having a pixel region in which a plurality of pixels including a photoelectric conversion unit are two-dimensionally arranged as a first substrate having a first electrode made of metal. A circuit board having a predetermined circuit as a second substrate having a second electrode formed of metal, the substrate being bonded to the first substrate, and the first substrate and An insulating film is formed on at least one bonding surface of the second substrate, in which an opening corresponding to the protrusion of the metal at the time of heat treatment after the bonding of the bonding surfaces is formed. The first electrode and the second electrode are solid-state imaging devices that are metal-bonded at the opening of the insulating film.

  In the semiconductor device and the solid-state imaging device according to one aspect of the present technology, at least one of a first substrate having a first electrode made of metal and a second substrate having a second electrode made of metal An insulating film in which an opening corresponding to the protrusion of the metal at the time of heat treatment after bonding of the bonding surfaces is formed on the bonding surface, and the first electrode and the second electrode, Metal bonding is performed at the opening of the insulating film.

  A manufacturing method according to one aspect of the present technology is a method in which a first substrate having a first electrode formed of metal and a second substrate having a second electrode formed of metal are bonded to each other by heat treatment, In the opening formed in the insulating film formed on the bonding surface of at least one of the first substrate and the second substrate, the metal is raised so that the first electrode and the second substrate are raised. A method of manufacturing a semiconductor device in which an electrode is metal-bonded.

  In the manufacturing method according to one aspect of the present technology, a first substrate having a first electrode made of metal and a second substrate having a second electrode made of metal are bonded together, and heat treatment is performed. Thus, the metal is raised in the opening formed in the insulating film formed on the bonding surface of at least one of the first substrate and the second substrate, and the first electrode and the second These electrodes are metal-bonded.

  According to one aspect of the present technology, the bonding strength can be further improved when two substrates are bonded to each other.

  Note that the effects described here are not necessarily limited, and may be any of the effects described in the present disclosure.

It is a figure showing the composition of the 1 embodiment of the solid imaging device to which this art is applied. It is principal part sectional drawing which shows the structure of a solid-state imaging device. It is the figure which represented typically the mode at the time of joining and heat processing in the structure of the bonding surface vicinity. It is principal part sectional drawing which shows the structure of a solid-state imaging device. It is principal part sectional drawing which shows the structure of a solid-state imaging device. It is principal part sectional drawing which shows the structure of a solid-state imaging device. It is principal part sectional drawing which shows the structure of a solid-state imaging device. It is principal part sectional drawing which shows the structure of a solid-state imaging device. It is principal part sectional drawing which shows the structure of a solid-state imaging device. It is a flowchart explaining the flow of the manufacturing process of a solid-state imaging device. It is the figure which represented a part of process of the 1st manufacturing process typically. It is the figure which represented a part of process of the 1st manufacturing process typically. It is the figure which represented a part of process of the 1st manufacturing process typically. It is the figure which represented a part of process of the 1st manufacturing process typically. It is the figure which represented a part of process of the 2nd manufacturing process typically. It is the figure which represented a part of process of the 2nd manufacturing process typically. It is the figure which represented a part of process of the 2nd manufacturing process typically. It is the figure which represented a part of process of the 2nd manufacturing process typically. It is the figure which represented a part of process of the 3rd manufacturing process typically. It is the figure which represented a part of process of the 3rd manufacturing process typically. It is the figure which represented a part of process of the 3rd manufacturing process typically. It is the figure which represented a part of process of the 3rd manufacturing process typically. It is a figure which shows the structural example of the electronic device using the solid-state imaging device to which this technique is applied. It is a block diagram which shows an example of a schematic structure of an in-vivo information acquisition system. It is a block diagram which shows an example of a schematic structure of a vehicle control system. It is explanatory drawing which shows an example of the installation position of a vehicle exterior information detection part and an imaging part.

  Hereinafter, embodiments of the present technology will be described with reference to the drawings. The description will be made in the following order.

1. 1. Schematic configuration example of solid-state imaging device 2. Configuration example of solid-state imaging device 3. Flow of manufacturing process of solid-state imaging device 4. Configuration example of electronic device Application examples

<1. Schematic configuration example of solid-state imaging device>

  FIG. 1 is a diagram illustrating a configuration of an embodiment of a solid-state imaging device to which the present technology is applied.

  In FIG. 1, the solid-state imaging device 1 includes a three-dimensional structure including a first substrate 11 as a sensor substrate and a second substrate 21 as a circuit substrate bonded to the first substrate 11 in a stacked state. This is a semiconductor device. The solid-state imaging device 1 is configured as an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor.

  In the solid-state imaging device 1, the first substrate 11 is provided with a pixel region 13 in which a plurality of pixels 12 including a photoelectric conversion unit are regularly arranged in a two-dimensional manner. In the pixel region 13, a plurality of pixel driving lines 14 are wired in the row direction, a plurality of vertical signal lines 15 are wired in the column direction, and one pixel 12 is connected to one pixel driving line 14 and one pixel driving line 14. It is arranged in a state of being connected to the vertical signal line 15.

  Each pixel 12 is provided with a photoelectric conversion unit, a floating diffusion (FD), and a pixel circuit including a plurality of transistors and the like. A plurality of pixels 12 may share part of the pixel circuit.

  On the other hand, the second substrate 21 is provided with peripheral circuits such as a vertical drive circuit 22, a column signal processing circuit 23, a horizontal drive circuit 24, and a system control circuit 25.

<2. Configuration Example of Solid-State Imaging Device>

(Basic structure)
FIG. 2 is a cross-sectional view of a principal part showing a structure (a part) of the solid-state imaging device 1 of FIG. Hereinafter, the detailed configuration of the solid-state imaging device 1 will be described with reference to the cross-sectional view of the main part.

  In FIG. 2, in the solid-state imaging device 1, the first bonding surface 11 </ b> S of the first substrate 11 and the second bonding surface 21 </ b> S of the second substrate 21 are arranged to face each other with the insulating film 107-2 interposed therebetween. Thus, the semiconductor device has a three-dimensional structure in which the first substrate 11 and the second substrate 21 are bonded together.

  In the first substrate 11, a TLV (Through Layer Via) 104-1 that penetrates each layer, a wiring layer, and the like are formed on an oxide film 101-1 formed on a surface layer of a semiconductor wafer (not shown). The TLV 104-1 is filled with a metal film 106-1 such as copper (Cu).

  On the other hand, in the second substrate 21, a TLV 104-2, a wiring layer, and the like are formed on the oxide film 101-2 formed on the surface layer of the semiconductor wafer 100-2. The TLV 104-2 is filled with a metal film 106-2 such as copper (Cu).

  That is, by bonding the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21, the metal film 106-1 filled in the TLV 104-1 and the TLV 104-2. Metal bonding is performed with the metal film 106-2 filled in the film.

  In FIG. 2, an insulating film 107-2 having a predetermined opening (groove) is formed on the second bonding surface 21 </ b> S side of the second substrate 21. Examples of the material of the insulating film 107-2 include a nitride film (P-SiN) and an oxide film (P-SiO), a nitride film doped with carbon (P-SiCN), and P-SiON. Can be used. That is, the insulating film 107-2 is a barrier insulating film and can be a silicon-based insulating film.

  The opening formed in the insulating film 107-2 is an opening formed at a position corresponding to the TLV 104-1 and the TLV 104-2, and after the first bonding surface 11S and the second bonding surface 21S are joined. The metal film 106-1 and the metal film 106-2 filled in the TLV 104-1 and the TLV 104-2, respectively, have shapes corresponding to the protrusions during the heat treatment.

  Here, FIG. 3 schematically shows the state of joining the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 and the subsequent heat treatment. Yes. In addition, in FIG. 3, it is a structure of the vicinity of the 1st bonding surface 11S and the 2nd bonding surface 21S, Comprising: Part of the structure containing TLV104-1 and TLV104-2 is expanded and shown in figure.

  FIG. 3A schematically illustrates a state at the time of joining the first bonding surface 11S and the second bonding surface 21S. In FIG. 3A, an insulating film 107-2 having an opening 109-2 is formed on the second bonding surface 21S side. Further, on the first bonding surface 11S side, an opening 109-1 is formed in the oxide film 101-1 on which the TLV 104-1 is formed.

  And the opening 109-1 formed in the 1st bonding surface 11S side by bonding the 1st bonding surface 11S of the 1st board | substrate 11 and the 2nd bonding surface 21S of the 2nd board | substrate 21 is bonded. Then, the space 110 is formed by the opening 109-2 formed on the second bonding surface 21S side.

  FIG. 3B schematically shows a state at the time of heat treatment after joining. In addition, as conditions of this heat processing, it can carry out for about 1 to 12 hours at the temperature of 150-450 degreeC, for example. Here, a case where copper (Cu) is used as the metal films 106-1 and 106-2 filled in the TLVs 104-1 and 104-2 will be described as an example.

  Generally, when heat treatment is applied to copper (Cu) having a large volume, such as copper (Cu) filled as the metal films 106-1 and 106-2 in the TLVs 104-1 and 104-2, so-called pumping is performed. It is known that the phenomenon occurs and copper (Cu) rises. In the present technology, by utilizing the local copper (Cu) bulging phenomenon (plastic deformation due to thermal stress) due to the heat treatment, the opening 109 is matched with the height of the copper (Cu) bulging (height rising). -1 and the size of the space 110 formed by the opening 109-2 are adjusted.

  3A, since the space 110 is formed by the opening 109-1 and the opening 109-2, during the subsequent heat treatment, as shown in FIG. 3B, the TLVs 104-1 and 104 are formed. -2 is raised as copper (Cu) filled as the metal films 106-1 and 106-2, and is pushed out to the space 110 by so-called self-alignment.

  As a result, as shown in FIG. 3B, in the space 110 formed when the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 are bonded, the TLV 104 is subjected to heat treatment. -1 and TLV 104-2 are subjected to metal bonding (Cu-Cu bonding) with copper (Cu) filled as the metal films 106-1 and 106-2, and the Cu electrodes are bonded to each other.

At this time, the region other than the Cu-Cu junction includes the oxide film 101-1 (for example, SiO ₂ ) on the first bonding surface 11S side and the insulating film 107-2 (for example, the second bonding surface 21S side). , P-SiN, P-SiO, P-SiCN, P-SiON), there is little concern that a junction between oxide film (SiO ₂ ) and copper (Cu) will be formed, Cu electrode Since mutual joining becomes possible, more sufficient joining property and intensity | strength can be ensured.

Conventionally, when copper (Cu) with a large volume such as TLV is mounted, when heat treatment is applied, a pumping phenomenon occurs, and copper (Cu) rises in the surrounding oxide film (SiO ₂ ) region, Joining Void or non-joining may occur, but this technique can be used to avoid it.

In other words, according to the present technology, the copper (Cu) metal raised by providing a space (corresponding to the space 110 in FIG. 3) in advance as a space for the copper (Cu) raised volume during the heat treatment. The membrane is self-aligned and pushed into the space. As a result, metal bonding (Cu-Cu bonding) between copper (Cu) is performed, and also in other regions, the insulating film and the oxide film or the insulating film are bonded to each other, and the oxide film (SiO ₂ ) There is little concern that a bonded portion of copper and copper (Cu) is formed, and the bonding strength can be improved as a whole when the substrates are bonded together.

  Further, by using this technology, it is not necessary to arrange a dummy electrode for improving the bonding strength, so that the capacity problem caused by arranging the dummy electrode can be solved and the characteristics of the semiconductor element can be improved. . Furthermore, it is possible to reduce layers by not arranging dummy electrodes.

(Example of variation)
By the way, the cross-sectional structure of the solid-state imaging device 1 shown in FIG. 2 is an example, and other cross-sectional structures can be adopted. Then, with reference to FIG. 4 thru | or FIG. 9, the example of the variation of the cross-sectional structure of the solid-state imaging device 1 of FIG. 1 is demonstrated. For comparison, FIG. 4 shows a structure in the case where the insulating film 107 as a barrier insulating film is not provided on the bonding surface of the first substrate 11 and the second substrate 21.

(Example in which an insulating film is formed only on one bonding surface)
FIG. 5 is a cross-sectional view of the main part of the structure in which the insulating film 107 is formed only on one of the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21. FIG.

  In FIG. 5, copper (Cu) filled as the metal film 106-1 in the TLV 104-1 on the first bonding surface 11S side and the metal film 106-2 on the TLV 104-2 on the second bonding surface 21S side. The junction with copper (Cu) filled as follows has the following structure.

  That is, at the time of bonding, an opening formed in the oxide film 101-1 on the first bonding surface 11S side (corresponding to the opening 109-1 in FIG. 3) and the insulating film 107- on the second bonding surface 21S side. 2 (corresponding to the opening 109-2 in FIG. 3) forms a space (corresponding to the space 110 in FIG. 3). During the heat treatment, copper (Cu) filled in the TLVs 104-1 and 104-2 as the metal films 106-1 and 106-2 rises into the space and is pushed out by self-alignment.

  As a result, in the space formed at the time of bonding (corresponding to the space 110 in FIG. 3), metal bonding (Cu—Cu bonding) by copper (Cu) filled as the metal films 106-1 and 106-2 at the time of heat treatment. ) Is performed, and the Cu electrodes are joined together.

  In the structure shown in FIG. 5, the structure of the bonding portion corresponds to the basic structure shown in FIG. 2, and the insulating film 107-2 is formed only on the second bonding surface 21S side. On the contrary, the insulating film 107-1 may be formed only on the first bonding surface 11S side. Even in this case, by providing an opening in the insulating film 107-1, a space can be formed at the time of bonding.

(Example in which an opening is formed only on one bonding surface)
FIG. 6 is a cross-sectional view of a main part of a structure in which an opening is formed only on one of the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21. It is.

  In FIG. 6, copper (Cu) filled as the metal film 106-1 in the TLV 104-1 on the first bonding surface 11S side and the metal film 106-2 on the TLV 104-2 on the second bonding surface 21S side. The junction with copper (Cu) filled as follows has the following structure.

  That is, during bonding, a space (corresponding to the space 110 in FIG. 3) is formed by the opening (corresponding to the opening 109-2 in FIG. 3) formed in the insulating film 107-2 on the second bonding surface 21S side. Is done. In the example of this structure, since the opening is not formed on the first bonding surface 11S side, a space is formed only by the opening on the second bonding surface 21S side. During the heat treatment, in this space, copper (Cu) filled as the metal films 106-1 and 106-2 in the TLVs 104-1 and 104-2 rises, and is pushed out by self-alignment and metal bonding is performed. And Cu electrodes are joined together.

  In addition, in the structure shown in FIG. 6, although the opening part by the insulating film 107-2 is formed only in the 2nd bonding surface 21S side as a structure of a junction part, on the contrary, the 1st bonding is carried out. An opening made of the insulating film 107-1 may be formed only on the surface 11S side. Even in this case, a space can be formed at the time of bonding only by the opening formed in the insulating film 107-1 on the first bonding surface 11S side.

(Example of insulating films formed on both bonded surfaces)
FIG. 7 is a cross-sectional view of a main part of a structure in which an insulating film 107 is formed on both the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21.

  In FIG. 7, copper (Cu) filled as the metal film 106-1 in the TLV 104-1 on the first bonding surface 11S side and the metal film 106-2 on the TLV 104-2 on the second bonding surface 21S side. The junction with copper (Cu) filled as follows has the following structure.

  That is, at the time of bonding, an opening formed in the insulating film 107-1 on the first bonding surface 11S side (corresponding to the opening 109-1 in FIG. 3) and the insulating film 107- on the second bonding surface 21S side. 2 (corresponding to the opening 109-2 in FIG. 3) forms a space (corresponding to the space 110 in FIG. 3). During the heat treatment, in this space, copper (Cu) filled as the metal films 106-1 and 106-2 in the TLVs 104-1 and 104-2 rises, and is pushed out by self-alignment and metal bonding is performed. And Cu electrodes are joined together.

(Example of stacking insulating films formed on one bonding surface)
FIG. 8 shows the main part of the structure in which the insulating film 107 formed on one of the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 is laminated. It is sectional drawing.

  In FIG. 8, copper (Cu) filled as the metal film 106-1 in the TLV 104-1 on the first bonding surface 11S side and the metal film 106-2 on the TLV 104-2 on the second bonding surface 21S side. The junction with copper (Cu) filled as follows has the following structure.

  That is, at the time of bonding, an opening formed in the insulating film 107-1 on the first bonding surface 11S side (corresponding to the opening 109-1 in FIG. 3) and the insulating film 107- on the second bonding surface 21S side. 2 (corresponding to the opening 109-2 in FIG. 3) forms a space (corresponding to the space 110 in FIG. 3). During the heat treatment, in this space, copper (Cu) filled as the metal films 106-1 and 106-2 in the TLVs 104-1 and 104-2 rises, and is pushed out by self-alignment and metal bonding is performed. And Cu electrodes are joined together.

  Here, the insulating film 107-2 is formed by stacking an insulating film 107a-2 and an insulating film 107b-2. The insulating film 107a-2 and the insulating film 107b-2 may be made of the same material or different materials as long as they are insulating films and have barrier properties. For example, P-SiC or the like can be used as a material for the insulating film 107a-2. For example, as a material of the insulating film 107b-2, an oxide film (P-SiO), P-SiC, or the like can be used.

  In the structure shown in FIG. 8, the two layers of the insulating film 107a-2 and the insulating film 107b-2 are shown as the layer of the insulating film 107-2. It may be. In the structure shown in FIG. 8, the case where the widths of the openings of the insulating film 107a-2 and the insulating film 107b-2 are the same has been described. The width and depth may be different. Such a structure in which the width and depth of the opening is different for each laminated insulating film will be described later with reference to FIGS.

(Example of opening larger than TLV)
FIG. 9 shows the main part of the structure in which the opening 109 formed in the insulating film 107 is larger than the TLV 104 in the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21. It is sectional drawing.

  In FIG. 9, copper (Cu) filled as the metal film 106-1 in the TLV 104-1 on the first bonding surface 11S side and the metal film 106-2 on the TLV 104-2 on the second bonding surface 21S side. The junction with copper (Cu) filled as follows has the following structure.

  That is, at the time of bonding, an opening formed in the insulating film 107-1 on the first bonding surface 11S side (corresponding to the opening 109-1 in FIG. 3) and the insulating film 107- on the second bonding surface 21S side. 2 (corresponding to the opening 109-2 in FIG. 3) forms a space (corresponding to the space 110 in FIG. 3). During the heat treatment, in this space, copper (Cu) filled as the metal films 106-1 and 106-2 in the TLVs 104-1 and 104-2 rises, and is pushed out by self-alignment and metal bonding is performed. And Cu electrodes are joined together.

  Here, in the structure and the like shown in FIG. 2 described above, the case where the width of the opening formed in the insulating film 107 is smaller than the width of the TLV 104 has been described. However, in the structure shown in FIG. -1 and the width of the opening formed in each of the insulating films 107-2 are larger than the widths of the TLV 104-1 and the TLV 104-2. Thus, even when the width of the opening is larger than the width of the TLV 104, a space can be formed at the time of bonding. As a result, during the heat treatment, the metal film 106-1 is formed on the TLVs 104-1 and 104-2. , 106-2 filled with copper (Cu), and the metal can be bonded by utilizing the fact that the copper is raised and pushed out into the space.

  The variation in the cross-sectional structure of the solid-state imaging device 1 described above is an example, and a space (corresponding to the space 110 in FIG. 3) is formed by the insulating film 107 or the like at the time of bonding. Other structures may be employed as long as the metal can be bonded by utilizing a metal bump phenomenon (plastic deformation due to thermal stress). For example, as described later, a structure in which a pad portion such as a Cu pad is provided instead of one TLV of the TLV 104-1 and the TLV 104-2 may be used.

(Example of opening design)
By the way, although it is an opening part (groove part) for forming a space at the time of joining, it can design as follows, for example.

  That is, the pumping amount (increased volume) of copper (Cu) after heat treatment is predicted in advance, and from the predicted value, the thickness of the insulating film sandwiched between the upper and lower electrodes to be connected and the width of the opening are determined. Just decide. When obtaining the predicted value, in addition to considering conditions such as the temperature during heat treatment and the volume expansion coefficient of copper (Cu), for example, the volume of copper (Cu) expanded by heat treatment is all deformed upward. You can also add preconditions such as

  Further, the opening formed in the insulating film can be designed so as to be opened inward with respect to the TLV. In addition, the total area ratio of the openings to the TLV can be designed in a range larger than 0% and smaller than 100%, for example, but the area ratio should be designed in a range exceeding 100%. It may be.

  Furthermore, as the shape of the opening formed in the insulating film, for example, various shapes such as a quadrangle and a circle can be adopted. The number of openings formed in one insulating film is not limited to one, and a plurality of openings may be formed. When a plurality of openings are formed, they can be arranged with a predetermined regularity, for example, arranged side by side or arranged on a diagonal line. Further, by arranging a plurality of openings, it is possible to improve a margin for bonding deviation.

<3. Flow of manufacturing process of solid-state imaging device>

  Next, the flow of the manufacturing process of the solid-state imaging device 1 will be described. FIG. 10 is a flowchart for explaining the flow of the manufacturing process of the solid-state imaging device 1. Here, as an example of the manufacturing process of the solid-state imaging device 1, three manufacturing processes will be described in order.

(1) First manufacturing process

  First, the flow of the first manufacturing process of the solid-state imaging device 1 will be described with reference to the schematic diagrams of FIGS. 11 to 14 together with the flowchart of FIG.

  In step S101, an oxide film forming process is performed. In this oxide film forming step, as shown in FIG. 11A, an oxide film 101 is formed on the surface layer of the semiconductor wafer 100 made of a semiconductor material such as single crystal silicon.

  Although not shown here, the semiconductor wafer 100 on which the oxide film 101 is formed includes a MOS transistor and a diffusion layer (not shown) for performing signal processing necessary as an integrated circuit, a wiring layer 102a, A plurality of wiring layers 102 such as the wiring layer 102b are provided. The material of the wiring layer 102 is not particularly limited as long as it is a metal film such as copper (Cu), aluminum (Al), or tungsten (W).

  In step S102, a TLV opening process is performed. In this TLV opening process, as shown in FIG. 11B, the dummy pad 103 and the TLV 104 penetrating each layer are opened on the oxide film 101 using lithography and a dry etching apparatus.

When opening the dummy pad 103 and the TLV 104, it may be performed in a lump or may be divided. For example, in the case of division processing, the etching conditions of TLV104 are, for example, normal temperature, pressure is set to 10 to 50 mTorr, Source Power is set to 1500 to 3500 W, and hexafluorocyclobutane (C4F6) and argon are used as process gases. (Ar) and oxygen (O ₂ ) are used, the gas flow rate ratio is C4F6 / Ar / O ₂ = 1/4/2, and the substrate bias is set to 500 to 2000 W.

Etching conditions for the dummy pad 103 include, for example, normal temperature, pressure of 10 to 50 mTorr, source power set to 500 to 2000 W, and process gases such as cyclobutane octafluoride (C4F8) and argon (Ar). Oxygen (O ₂ ) is used, the gas flow rate ratio is C4F8 / Ar / O ₂ = 1/6/1, and the substrate bias is set to 500 to 2500 W.

  Here, as the dimensions of the dummy pad 103, for example, it is desirable that the width is about 50 nm to 5 μm and the depth is about 100 to 700 nm. As for TLV104, the width is desirably about 500 nm to 5 μm and the depth is desirably about 1 to 10 μm. Furthermore, as a variation of the shape viewed from the surface of the TLV 104, any shape may be used as long as the shape functions as a via, such as a square, an octagon, and a circle.

  In step S103, a metal film forming step is performed. In this metal film forming step, as shown in FIG. 11C, a barrier metal film 105 and a metal film 106 made of a metal such as copper (Cu) are formed so as to cover the upper surfaces of the dummy pad 103 and the TLV 104.

  In the following description, the case where copper (Cu) is used as the metal film 106 will be described as an example. As the barrier metal film 105, for example, tantalum (Ta), tantalum nitride (TaN), titanium (Ti), or titanium nitride (TiN) is preferably used, and a laminated structure thereof may be used.

  In step S104, a planarization process is performed. In this planarization step, as shown in FIG. 12D, copper (Cu) as the metal film 106 is removed using a technique such as planarization CMP (Chemical Mechanical Polishing).

  In step S105, an insulating film forming step is performed. In this insulating film forming step, as shown in FIG. 12E, an insulating film 107 is formed on the surface of the oxide film 101 on which the barrier metal film 105 and the metal film 106 are formed.

  Here, examples of the material of the insulating film 107 include a nitride film (P-SiN) and an oxide film (P-SiO), a nitride film doped with carbon (P-SiCN), and P-SiON. There is no particular limitation as long as it has insulating properties. Moreover, as a film thickness of the insulating film 107, it can form into a film in the range of 0.1 nm-3 micrometers, for example.

  In step S106, a patterning process is performed. In this patterning step, as shown in FIG. 12F, a photoresist 108 is applied on the insulating film 107, and then an opening (groove) is patterned.

  Here, the TLV 104 can be designed to be opened inward. In addition, the total area ratio of the openings (grooves) with respect to the TLV 104 can be designed in a range larger than 0% and smaller than 100%, for example, but the area ratio is in a range exceeding 100%. You may make it design.

  Furthermore, as for the patterning of the opening (groove), the shape of the pattern can be, for example, a quadrangle or a circle as in the case of the TLV 104 in the step S102. Further, a plurality of openings (grooves) may be arranged.

  In step S107, an insulating film opening process is performed. In this insulating film opening process, as shown in FIG. 13G, the insulating film 107 is opened and filled with a metal film 106 such as copper (Cu) by dry etching using the pattern generated in step S106. An opening 109 (groove) is formed on the TLV 104.

As dry etching conditions here, for example, at room temperature, pressure is set to 10 to 100 mTorr, Source Power is set to 100 to 1000 W, and acetylene (C2H2), argon (Ar), and oxygen (O ₂ ) are used as process gases. , The gas flow ratio is C2H2 / Ar / O ₂ = 2/30/1, and the substrate bias is set to 100 to 1500 W.

  In step S108, a joining process is performed. In this joining step, the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 are bonded together.

  However, in the example of the first manufacturing process, the second substrate 21 corresponds to the substrate obtained in the steps S101 to S107, and the first substrate 11 has the same structure as the second substrate 21. And Here, for the convenience of explanation, the configuration of the first substrate 11 is described by describing “−1” as the symbol, and the configuration of the second substrate 21 is described by describing “−2” as the symbol.

  That is, in the second substrate 21, the opening 109-2 is formed in the insulating film 107-2 with respect to the TLV 104-2, but the first substrate 11 is also insulated from the TLV 104-1. An opening 109-1 is formed in the film 107-1.

  Then, in the step S108, the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 are bonded to each other, as shown in FIG. 13H. A space 110 is formed by the opening 109-1 formed on the mating surface 11S side and the opening 109-2 formed on the second bonding surface 21S side.

  In step S109, a heat treatment process is performed. In this heat treatment process, heat treatment is performed on the first substrate 11 (semiconductor wafer 100-1) and the second substrate 21 (semiconductor wafer 100-2) joined in step S108. The heat treatment can be performed at a temperature of 150 to 450 ° C. for about 1 to 12 hours, for example.

  Here, when heat treatment is applied to copper (Cu) having a large volume, such as copper (Cu) as the metal films 106-1 and 106-2 filled in the TLVs 104-1 and 104-2, copper (Cu) is applied. As mentioned above, the bulge is raised.

  Further, in the first manufacturing process, as shown in FIG. 13H, in the structure at the time of bonding, the opening 109-1 formed on the first bonding surface 11S side and the second bonding surface 21S side are formed. A space 110 is formed by the opened portion 109-2. Therefore, at the time of heat treatment, copper (Cu) as the metal films 106-1 and 106-2 filled in the TLVs 104-1 and 104-2 rises and is pushed out to the space 110 by self-alignment.

  As a result, as shown in FIG. 14I, in the space 110 formed at the time of joining the first substrate 11 and the second substrate 21, the metal films 106- filled in the TLVs 104-1 and 104-2, respectively, during the heat treatment. Metal bonding by copper (Cu) as 1,106-2 is performed.

That is, conventionally, when heat treatment is applied to copper (Cu) having a large volume such as TLV, a pumping phenomenon occurs, and copper (Cu) rises, and in the surrounding oxide film (SiO ₂ ) region, There is a possibility that bonding Void or non-bonding may occur. However, in the first manufacturing process, an escape space for the volume due to the copper (Cu) bulging during the heat treatment is provided as the space 110 in advance. .

  The first manufacturing process is performed as described above.

  In the first manufacturing process, an insulating film is sandwiched between upper and lower electrodes to be connected, and metal bonding (Cu-Cu bonding) is performed locally using plastic deformation caused by thermal stress of copper (Cu). Yes.

If this first manufacturing process is used, there is little concern that a junction between an oxide film (SiO ₂ ) and copper (Cu) will be formed, and Cu electrodes can be joined together. Strength can be secured. In addition, the region other than the region of metal bonding (Cu—Cu bonding) is a bonding between the insulating films, and from this point, the overall bonding strength can be improved.

  The structure of the solid-state imaging device 1 manufactured in the first manufacturing process corresponds to the structure shown in FIG. 7, but for example, only one of the first substrate 11 and the second substrate 21 is By forming the insulating film 107, the solid-state imaging device 1 having the structure shown in FIGS. 5 and 6 can be manufactured.

(2) Second manufacturing process

  Next, the flow of the second manufacturing process of the solid-state imaging device 1 will be described with reference to the schematic diagrams of FIGS. 15 to 18 together with the flowchart of FIG.

  In step S101, an oxide film forming process is performed. In this oxide film forming step, an oxide film 201 is formed on the surface layer of the semiconductor wafer 200 as shown in FIG. 15A. This oxide film forming step is the same as the oxide film forming step of the first manufacturing process described above.

  In step S102, a TLV opening process is performed. In this TLV opening step, as shown in FIG. 15B, the dummy pad 203 and the TLV 204 penetrating each layer are opened on the oxide film 201 using lithography and a dry etching apparatus. This TLV opening process is the same as the TLV opening process of the first manufacturing process described above.

  In step S103, a metal film forming step is performed. In this metal film forming step, as shown in FIG. 15C, a barrier metal film 205 and a metal film 206 such as copper (Cu) are formed so as to cover the upper surfaces of the dummy pad 203 and the TLV 204. This metal film forming process is the same as the metal film forming process of the first manufacturing process described above.

  In step S104, a planarization process is performed. In this planarization step, as shown in FIG. 16D, copper (Cu) as the metal film 106 is removed using a technique such as planarization CMP, for example. This flattening step is the same as the flattening step of the first manufacturing process described above.

  In step S105, an insulating film forming step is performed. In this insulating film forming step, as shown in FIG. 16E, an insulating film 207 is formed on the surface of the oxide film 201 on which the metal film 206 and the like are formed. This insulating film forming step is the same as the insulating film forming step in the first manufacturing process described above.

  In step S106, a patterning process is performed. In this patterning step, as shown in FIG. 16F, a photoresist 208 is applied on the insulating film 207, and then an opening (groove) is patterned. This patterning process is the same as the patterning process of the first manufacturing process described above.

  In step S107, an insulating film opening process is performed. In this insulating film opening step, as shown in FIG. 17G, the insulating film 207 is opened and filled with a metal film 206 such as copper (Cu) by dry etching using the pattern formed in the step S106. An opening 209 is formed on the TLV 204. This insulating film opening step is the same as the insulating film opening step in the first manufacturing process described above.

  In step S108, a joining process is performed. In this joining step, the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 are bonded together.

  However, in the example of the second manufacturing process, the second substrate 21 corresponds to the substrate obtained in the processes of steps S201 to S207, and the first substrate 11 has a pad portion 211 that is bonded to the TLV 204 instead of the TLV 204. It shall be comprised with the formed structure. Also here, for convenience of explanation, the configuration of the first substrate 11 is described with a symbol “−1”, and the configuration of the second substrate 21 is described with a symbol “−2”.

  That is, as shown in FIG. 17H, in the second substrate 21, an opening 209-2 is formed in the insulating film 207-2 with respect to the TLV 204-2. On the other hand, as shown in FIG. 17H, in the first substrate 11, a pad portion 211-1 bonded to the TLV 204-2 is formed on the oxide film 201-1, and an insulating film formed on the surface thereof. In 207-1, an opening 209-1 is formed inside the pad 211-1.

  Then, in the step S108, the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 are bonded to each other, as shown in FIG. A space 210 is formed by the opening 209-1 formed on the mating surface 11S side and the opening 209-2 formed on the second laminating surface 21S side.

  The pad portion 211-1 in the first substrate 11 is a Cu pad when the metal film 206-2 filled in the TLV 204-2 in the second substrate 21 is copper (Cu).

  In step S109, a heat treatment process is performed. In this heat treatment process, heat treatment is performed on the first substrate 11 (semiconductor wafer 200-1) and the second substrate 21 (semiconductor wafer 200-2) joined in step S108. The heat treatment can be performed at a temperature of 150 to 450 ° C. for about 1 to 12 hours, for example.

  Here, in the second manufacturing process, as shown in FIG. 17I, in the structure at the time of joining, the opening 209-1 formed on the first bonding surface 11S side and the second bonding surface 21S side are formed. A space 210 is formed by the formed opening 209-2. Therefore, at the time of heat treatment, copper (Cu) as the metal film 206-2 filled in the TLV 204-2 is raised and pushed out to the space 210 by self-alignment.

  As a result, as shown in FIG. 18J, in the space 210 formed when the first substrate 11 and the second substrate 21 are joined, copper (as the metal film 206-2 filled in the TLV 204-2 during the heat treatment) Metal bonding by Cu) will be performed. That is, in the second manufacturing process, a space for a volume due to the copper (Cu) bulging during heat treatment is provided in advance as the space 210.

  The second manufacturing process is performed as described above.

  In the second manufacturing process, an insulating film is sandwiched between the TLV and Cu pad to be connected, and metal bonding (Cu-Cu bonding) is locally performed using plastic deformation caused by thermal stress of copper (Cu). Is going.

  That is, in the first manufacturing process described above, TLVs 104-1 and 104-2 are formed on both the first substrate 11 and the second substrate 21, and the metal film 106-1 such as copper (Cu) is formed. In the second manufacturing process, when the first substrate 11 and the second substrate 21 are joined, a pad portion 211-1 such as a Cu pad, and copper ( A TLV 204-2 filled with a metal film 206-2 such as Cu) is opposed and joined.

  In the second manufacturing process, since the pad portion 211-1 and the TLV 204-2 are bonded to each other, the pad portion 211-1 such as a Cu pad tends to be erosion (concave shape). ), The metal film 206-2 filled in the TLV 204-2 of the second substrate 21, for example, copper (Cu) is raised, so that the space 210 is sufficiently filled. Therefore, in the second manufacturing process, it is possible to improve not only the bonding but also the margin of electrical connection.

(3) Third manufacturing process

  Finally, the flow of the third manufacturing process of the solid-state imaging device 1 will be described with reference to the schematic diagrams of FIGS. 19 to 22 as well as the flowchart of FIG.

  In step S101, an oxide film forming process is performed. In this oxide film forming step, an oxide film 301 is formed on the surface layer of the semiconductor wafer 300 as shown in FIG. 19A. This oxide film forming step is the same as the oxide film forming step of the first manufacturing process described above.

  In step S102, a TLV opening process is performed. In this TLV opening step, as shown in FIG. 19B, a dummy pad 303 and a TLV 304 penetrating each layer are opened on the oxide film 301 using lithography and a dry etching apparatus. This TLV opening process is the same as the TLV opening process of the first manufacturing process described above.

  In step S103, a metal film forming step is performed. In this metal film forming step, as shown in FIG. 19C, a barrier metal film 305 and a metal film 306 such as copper (Cu) are formed so as to cover the upper surfaces of the dummy pad 303 and the TLV 304. This metal film forming process is the same as the metal film forming process of the first manufacturing process described above.

  In step S104, a planarization process is performed. In this planarization step, as shown in FIG. 20D, copper (Cu) as the metal film 306 is removed using a technique such as planarization CMP, for example. This flattening step is the same as the flattening step of the first manufacturing process described above.

  In step S105, an insulating film forming step is performed. In this insulating film forming step, as shown in FIG. 20E, a first insulating film 307a and a second insulating film 307b are formed on the surface of the oxide film 301 on which the metal film 306 and the like are formed. That is, the first insulating film 307 a and the second insulating film 307 b are stacked on the surface of the oxide film 301.

Here, the material of the first insulating film 307a may be, for example, a nitride film (P-SiN), a nitride film doped with carbon (P-SiCN), or P-SiON. And if it has barrier property, it will not specifically limit. The material of the second insulating film 307b is preferably a material having a different etch rate (Etch Rate) from the material of the first insulating film 307a, such as an oxide film (SiO ₂ ).

  As a method for forming these insulating films, for example, a plasma CVD method, an ALD CVD method, an HDP CVD method, an O3 TEOS CVD method, or an organic oxide film applied by a spin coater may be used. The first insulating film 307a and the second insulating film 307b can be formed in a range of 0.1 nm to 3 μm, for example, by combining the thicknesses of the stacked insulating films. However, the film thickness of the first insulating film 307a and the film thickness of the second insulating film 307b may be the same or different.

  In step S106, a patterning process is performed. In this patterning step, as shown in FIG. 20F, a photoresist 308 is applied on the laminated insulating film 307 (first insulating film 307a, second insulating film 307b), and then the opening (groove) is patterned. Is done.

  Here, the TLV 304 can be designed to be opened inward. Further, the total area ratio of the openings (grooves) with respect to the TLV 304 can be designed, for example, in a range larger than 0% and smaller than 100%, but the area ratio is in a range exceeding 100%. You may make it design.

  Furthermore, as for the patterning of the opening (groove), the shape of the pattern can be, for example, a quadrangle or a circle as in the case of the TLV 104 in the step S102. Further, a plurality of openings (grooves) may be arranged.

  In the planarization step (S104), since the planarization is performed using a method such as a planarization CMP, it is not necessary to use a method such as the planarization CMP in a subsequent step such as the patterning step (S106). There is merit in process.

  In step S107, an insulating film opening process is performed. In this insulating film opening step, as shown in FIG. 21G, the first insulating film 307a and the second insulating film 307b are opened by dry etching using the pattern formed in the step S106, and copper (Cu) or the like is opened. An opening 309 (groove) is formed on the TLV 304 filled with the metal film 306.

  At this time, the first insulating film 307a and the second insulating film 307b are formed so that the width of the opening 309 (groove portion) differs depending on the material by making the etch rate different.

  In the structure shown in FIG. 21G, the width of the opening of the first insulating film 307a is smaller than the width of the opening of the second insulating film 307b, but the etching conditions are changed. The width of the opening may be reversed. That is, the width of the opening of the first insulating film 307a may be larger than the width of the opening of the second insulating film 307b.

As a dry etching condition, a method of switching the etching step for each layer is preferable. As an example, first, the etching conditions for the first insulating film 307a are normal temperature, the pressure is set to 10 to 100 mTorr, the source power is set to 100 to 1000 W, and acetylene (C2H2) and argon are used as process gases. (Ar) and oxygen (O ₂ ) are used, the gas flow rate ratio is C ₂ H ₂ / Ar / O ₂ = 2/30/1, and the substrate bias is set to 100 to 1500 W.

On the other hand, as dry etching conditions for the second insulating film 307b, normal temperature, pressure is set to 10 to 50 mTorr, Source Power is set to 500 to 2000 W, and process gas is cyclobutane octafluoride (C4F8). Argon (Ar) and oxygen (O ₂ ) are used, the gas flow rate ratio is C4F8 / Ar / O ₂ = 1/6/1, and the substrate bias is set to 500 to 2500 W.

  In step S108, a joining process is performed. In this joining step, the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 are bonded together.

  However, in the example of the third manufacturing process, the second substrate 21 corresponds to the substrate obtained in the steps S101 to S107, and the first substrate 11 basically has the same structure as the second substrate 21. Shall be composed. Also here, for convenience of explanation, the configuration of the first substrate 11 is described with a symbol “−1”, and the configuration of the second substrate 21 is described with a symbol “−2”.

  That is, the second substrate 21 is formed by laminating the first insulating film 307a-2 and the second insulating film 307b-2 as a barrier insulating film on the second bonding surface 21S side, with respect to the TLV 304-2. Thus, an opening 309-2 is formed. On the other hand, in the 1st board | substrate 11, the insulating film 307-1 as a barrier insulating film is formed in a single layer in the 1st bonding surface 11S side, and the opening part 309-1 is formed with respect to TLV304-1. Has been.

  Then, in the step S108, the first bonding surface 11S of the first substrate 11 and the second bonding surface 21S of the second substrate 21 are bonded to each other, as shown in FIG. 21H. An opening 309-1 formed in the insulating film 307-1 on the mating surface 11S side, and an opening formed in the first insulating film 307a-2 and the second insulating film 307b-2 on the second bonding surface 21S side A space 310 is formed by 309-2.

  In the step S109, a heat treatment step is performed. In this heat treatment step, heat treatment is performed on the first substrate 11 (semiconductor wafer 300-1) and the second substrate 21 (semiconductor wafer 300-2) joined in step S108. The heat treatment can be performed at a temperature of 150 to 450 ° C. for about 1 to 12 hours, for example.

  Here, in the third manufacturing process, as shown in FIG. 21H, in the structure at the time of joining, the opening 309-1 formed on the first bonding surface 11S side and the second bonding surface 21S side are formed. A space 310 is formed by the formed opening 309-2. Therefore, at the time of heat treatment, copper (Cu) as the metal films 306-1 and 306-2 filled in the TLVs 304-1 and 304-2 rises and is pushed out to the space 310 by self-alignment.

  As a result, as shown in FIG. 22I, in the space 310 formed when the first substrate 11 and the second substrate 21 are joined, the metal films 306- filled in the TLVs 304-1 and 304-2, respectively, during the heat treatment. Metal bonding with copper (Cu) as 1,306-2 is performed. That is, in the third manufacturing process, an escape space for the volume due to the copper (Cu) bulging during the heat treatment is provided as the space 310 in advance.

  The third manufacturing process is performed as described above.

  In the third manufacturing process, a laminated insulating film is sandwiched between upper and lower electrodes to be connected, and metal bonding (Cu-Cu bonding) is locally performed using plastic deformation due to thermal stress of copper (Cu). It is carried out.

If this third manufacturing process is used, there is little concern that a junction between an oxide film (SiO ₂ ) and copper (Cu) will be formed, and Cu electrodes can be joined together. Strength can be secured. In addition, the region other than the region of metal bonding (Cu—Cu bonding) is a bonding between the insulating films, and from this point, the overall bonding strength can be improved.

  In the third manufacturing process, the insulating film through two substrates can be laminated to change the cross-sectional shape of the opening (groove). For example, the width of the opening of the insulating film immediately above the TLV can be changed. By reducing the size and applying stress, it is possible to promote the copper (Cu) bulge and improve the copper (Cu) metal junction margin.

  In the above description, the method of opening the first insulating film 307a and the second insulating film 307b as the stacked insulating films 307 in a lump is described. However, the method of dividing and opening is used. May be.

  Further, the solid-state imaging device 1 manufactured in the third manufacturing process corresponds to the structure shown in FIG. 8 in which the width of the opening is changed for each stacked insulating film. By setting the width of the opening for each film to the same width, the solid-state imaging device 1 having the structure shown in FIG. 8 can be manufactured.

<4. Configuration example of electronic device>

  The solid-state imaging device 1 as the semiconductor device described above is applied to, for example, a camera system such as a digital camera or a video camera, a mobile phone having an imaging function, or an electronic device such as another device having an imaging function. Can do.

  FIG. 23 is a diagram illustrating a configuration example of an electronic apparatus using a solid-state imaging device to which the present technology is applied. FIG. 23 shows a configuration example of an imaging apparatus 1000 as a video camera capable of capturing a still image or a moving image as an example of such an electronic apparatus.

  In FIG. 23, an imaging apparatus 1000 includes a solid-state imaging apparatus 1001, an optical system 1002 that guides incident light to a light receiving sensor unit of the solid-state imaging apparatus 1001, a shutter apparatus 1003, and a drive circuit 1004 that drives the solid-state imaging apparatus 1001. A signal processing circuit 1005 that processes an output signal of the solid-state imaging device 1001.

  As the solid-state imaging device 1001, the above-described solid-state imaging device 1 (FIG. 1) is applied. The optical system (optical lens) 1002 forms image light (incident light) from the subject on the imaging surface of the solid-state imaging device 1001. As a result, signal charges are accumulated in the solid-state imaging device 1001 for a certain period. Such an optical system 1002 may be an optical lens system including a plurality of optical lenses.

  The shutter device 1003 controls a light irradiation period and a light shielding period for the solid-state imaging device 1001. The drive circuit 1004 supplies drive signals to the solid-state imaging device 1001 and the shutter device 1003, and controls the signal output operation to the signal processing circuit 1005 of the solid-state imaging device 1001 and the shutter device by the supplied drive signal (timing signal). The shutter operation of 1003 is controlled. That is, the drive circuit 1004 performs a signal transfer operation from the solid-state imaging device 1001 to the signal processing circuit 1005 by supplying a drive signal (timing signal).

  The signal processing circuit 1005 performs various types of signal processing on the signal transferred from the solid-state imaging device 1001. The video signal obtained by this signal processing is stored in a storage medium such as a subsequent memory or output to a monitor, for example.

  According to the electronic apparatus using the solid-state imaging device to which the present technology is applied as described above, the solid-state imaging device 1 having a further improved bonding strength when the two substrates are stacked and bonded together is replaced with the solid-state imaging device 1001. Can be used as

<5. Application example>

  The technology according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure may be applied to an in-vivo information acquisition system for a patient using a capsule endoscope.

  FIG. 24 is a diagram illustrating an example of a schematic configuration of an in-vivo information acquisition system 5400 to which the technology according to the present disclosure can be applied. Referring to FIG. 24, the in-vivo information acquisition system 5400 includes a capsule endoscope 5401 and an external control device 5423 that comprehensively controls the operation of the in-vivo information acquisition system 5400. During the examination, the capsule endoscope 5401 is swallowed by the patient. The capsule endoscope 5401 has an imaging function and a wireless communication function, and moves inside the organs such as the stomach and intestine by peristaltic movement or the like until it is spontaneously discharged from the patient. Images (hereinafter also referred to as in-vivo images) are sequentially captured at predetermined intervals, and information about the in-vivo images is sequentially wirelessly transmitted to the external control device 5423 outside the body. The external control device 5423 generates image data for displaying the in-vivo image on a display device (not shown) based on the received information about the in-vivo image. In the in-vivo information acquisition system 5400, in this manner, an image obtained by imaging the state of the patient's body can be obtained at any time from when the capsule endoscope 5401 is swallowed until it is discharged.

  The configurations and functions of the capsule endoscope 5401 and the external control device 5423 will be described in more detail. As illustrated, a capsule endoscope 5401 includes a light source unit 5405, an imaging unit 5407, an image processing unit 5409, a wireless communication unit 5411, a power supply unit 5415, a power supply unit 5417, and a state detection unit in a capsule-type housing 5403. The functions of the unit 5419 and the control unit 5421 are mounted.

  The light source unit 5405 is composed of a light source such as an LED (light emitting diode), for example, and irradiates light onto the imaging field of the imaging unit 5407.

  The imaging unit 5407 includes an imaging element and an optical system including a plurality of lenses provided in the preceding stage of the imaging element. Reflected light (hereinafter referred to as observation light) of light irradiated on the body tissue to be observed is collected by the optical system and enters the image sensor. The imaging element receives the observation light and photoelectrically converts it to generate an electrical signal corresponding to the observation light, that is, an image signal corresponding to the observation image. The image signal generated by the imaging unit 5407 is provided to the image processing unit 5409. Note that as the imaging device of the imaging unit 5407, various known imaging devices such as a complementary metal oxide semiconductor (CMOS) image sensor or a charge coupled device (CCD) image sensor may be used.

  The image processing unit 5409 is configured by a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), and performs various signal processing on the image signal generated by the imaging unit 5407. The signal processing may be minimal processing (for example, image data compression, frame rate conversion, data rate conversion, and / or format conversion, etc.) for transmitting the image signal to the external control device 5423. . Since the image processing unit 5409 is configured to perform only the minimum necessary processing, the image processing unit 5409 can be realized with a smaller size and lower power consumption. Is preferred. However, if there is room in the space or power consumption in the housing 5403, the image processing unit 5409 may perform further signal processing (for example, noise removal processing or other high image quality processing). Good. The image processing unit 5409 provides the image signal subjected to signal processing to the wireless communication unit 5411 as RAW data. Note that when the state detection unit 5419 acquires information about the state (movement, posture, etc.) of the capsule endoscope 5401, the image processing unit 5409 associates the information with the information and wirelessly transmits the image signal. The communication unit 5411 may be provided. Thereby, the position in the body where the image was captured, the imaging direction of the image, and the like can be associated with the captured image.

  The wireless communication unit 5411 includes a communication device that can transmit and receive various types of information to and from the external control device 5423. The communication apparatus includes an antenna 5413, a processing circuit that performs modulation processing for signal transmission and reception, and the like. The wireless communication unit 5411 performs predetermined processing such as modulation processing on the image signal subjected to signal processing by the image processing unit 5409, and transmits the image signal to the external control device 5423 via the antenna 5413. In addition, the wireless communication unit 5411 receives a control signal related to drive control of the capsule endoscope 5401 from the external control device 5423 via the antenna 5413. The wireless communication unit 5411 provides the received control signal to the control unit 5421.

  The power feeding unit 5415 includes a power receiving antenna coil, a power regeneration circuit that regenerates power from a current generated in the antenna coil, a booster circuit, and the like. The power feeding unit 5415 generates power using a so-called non-contact charging principle. Specifically, when an external magnetic field (electromagnetic wave) is applied to the antenna coil of the power feeding unit 5415, an induced electromotive force is generated in the antenna coil. The electromagnetic wave may be a carrier wave transmitted from the external control device 5423 via the antenna 5425, for example. Electric power is regenerated from the induced electromotive force by the power regeneration circuit, and the potential is appropriately adjusted in the booster circuit, thereby generating power for storage. The electric power generated by the power supply unit 5415 is stored in the power supply unit 5417.

  The power supply unit 5417 is configured by a secondary battery and stores the electric power generated by the power supply unit 5415. In FIG. 24, in order to avoid the drawing from being complicated, illustration of an arrow or the like indicating a power supply destination from the power supply unit 5417 is omitted, but the power stored in the power supply unit 5417 is stored in the light source unit 5405. The imaging unit 5407, the image processing unit 5409, the wireless communication unit 5411, the state detection unit 5419, and the control unit 5421 can be used for driving them.

  The state detection unit 5419 includes a sensor for detecting the state of the capsule endoscope 5401 such as an acceleration sensor and / or a gyro sensor. The state detection unit 5419 can acquire information about the state of the capsule endoscope 5401 from the detection result of the sensor. The state detection unit 5419 provides the acquired information about the state of the capsule endoscope 5401 to the image processing unit 5409. In the image processing unit 5409, as described above, information about the state of the capsule endoscope 5401 can be associated with the image signal.

  The control unit 5421 is configured by a processor such as a CPU, and comprehensively controls the operation of the capsule endoscope 5401 by operating according to a predetermined program. The control unit 5421 drives the light source unit 5405, the imaging unit 5407, the image processing unit 5409, the wireless communication unit 5411, the power supply unit 5415, the power supply unit 5417, and the state detection unit 5419 according to a control signal transmitted from the external control device 5423. By appropriately controlling, the function in each unit as described above is realized.

  The external control device 5423 can be a processor such as a CPU or GPU, or a microcomputer or a control board in which a processor and a storage element such as a memory are mounted. The external control device 5423 includes an antenna 5425 and is configured to be able to transmit and receive various types of information to and from the capsule endoscope 5401 through the antenna 5425. Specifically, the external control device 5423 controls the operation of the capsule endoscope 5401 by transmitting a control signal to the control unit 5421 of the capsule endoscope 5401. For example, the light irradiation condition for the observation target in the light source unit 5405 can be changed by a control signal from the external control device 5423. In addition, an imaging condition (for example, a frame rate or an exposure value in the imaging unit 5407) can be changed by a control signal from the external control device 5423. In addition, the content of processing in the image processing unit 5409 and the conditions (for example, the transmission interval and the number of transmission images) for the wireless communication unit 5411 to transmit an image signal may be changed by a control signal from the external control device 5423. .

  Further, the external control device 5423 performs various image processing on the image signal transmitted from the capsule endoscope 5401, and generates image data for displaying the captured in-vivo image on the display device. As the image processing, for example, development processing (demosaic processing), high image quality processing (band enhancement processing, super-resolution processing, NR (Noise reduction) processing and / or camera shake correction processing, etc.), and / or enlargement processing ( Various known signal processing such as electronic zoom processing may be performed. The external control device 5423 controls driving of a display device (not shown) to display an in-vivo image captured based on the generated image data. Alternatively, the external control device 5423 may cause the generated image data to be recorded on a recording device (not shown) or may be printed out on a printing device (not shown).

  Heretofore, an example of the in-vivo information acquisition system 5400 to which the technology according to the present disclosure can be applied has been described. Of the configurations described above, the solid-state imaging device 1 can be used as the imaging element of the imaging unit 5407. According to the solid-state imaging device 1, when two substrates are stacked and bonded together, the bonding strength can be further improved.

  The technology according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure may be any type of movement such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, personal mobility, an airplane, a drone, a ship, a robot, a construction machine, and an agricultural machine (tractor). You may implement | achieve as an apparatus mounted in a body.

  FIG. 25 is a block diagram illustrating a schematic configuration example of a vehicle control system 7000 that is an example of a mobile control system to which the technology according to the present disclosure can be applied. The vehicle control system 7000 includes a plurality of electronic control units connected via a communication network 7010. In the example shown in FIG. 25, the vehicle control system 7000 includes a drive system control unit 7100, a body system control unit 7200, a battery control unit 7300, a vehicle exterior information detection unit 7400, a vehicle interior information detection unit 7500, and an integrated control unit 7600. . A communication network 7010 that connects the plurality of control units conforms to an arbitrary standard such as CAN (Controller Area Network), LIN (Local Interconnect Network), LAN (Local Area Network), or FlexRay (registered trademark). It may be an in-vehicle communication network.

  Each control unit includes a microcomputer that performs arithmetic processing according to various programs, a storage unit that stores programs executed by the microcomputer or parameters used for various calculations, and a drive circuit that drives various devices to be controlled. Is provided. Each control unit includes a network I / F for communicating with other control units via a communication network 7010, and is connected to devices or sensors inside and outside the vehicle by wired communication or wireless communication. A communication I / F for performing communication is provided. In FIG. 25, as a functional configuration of the integrated control unit 7600, a microcomputer 7610, a general-purpose communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiving unit 7650, an in-vehicle device I / F 7660, an audio image output unit 7670, An in-vehicle network I / F 7680 and a storage unit 7690 are illustrated. Similarly, other control units include a microcomputer, a communication I / F, a storage unit, and the like.

  The drive system control unit 7100 controls the operation of the device related to the drive system of the vehicle according to various programs. For example, the drive system control unit 7100 includes a driving force generator for generating a driving force of a vehicle such as an internal combustion engine or a driving motor, a driving force transmission mechanism for transmitting the driving force to wheels, and a steering angle of the vehicle. It functions as a control device such as a steering mechanism that adjusts and a braking device that generates a braking force of the vehicle. The drive system control unit 7100 may have a function as a control device such as ABS (Antilock Brake System) or ESC (Electronic Stability Control).

  A vehicle state detection unit 7110 is connected to the drive system control unit 7100. The vehicle state detection unit 7110 includes, for example, a gyro sensor that detects the angular velocity of the rotational movement of the vehicle body, an acceleration sensor that detects the acceleration of the vehicle, an operation amount of an accelerator pedal, an operation amount of a brake pedal, and steering of a steering wheel. At least one of sensors for detecting an angle, an engine speed, a rotational speed of a wheel, or the like is included. The drive system control unit 7100 performs arithmetic processing using a signal input from the vehicle state detection unit 7110, and controls an internal combustion engine, a drive motor, an electric power steering device, a brake device, or the like.

  The body system control unit 7200 controls operations of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 7200 functions as a keyless entry system, a smart key system, a power window device, or a control device for various lamps such as a headlamp, a back lamp, a brake lamp, a blinker, or a fog lamp. In this case, the body control unit 7200 can be input with radio waves or various switch signals transmitted from a portable device that substitutes for a key. The body system control unit 7200 receives input of these radio waves or signals, and controls a door lock device, a power window device, a lamp, and the like of the vehicle.

  The battery control unit 7300 controls the secondary battery 7310 that is a power supply source of the drive motor according to various programs. For example, information such as battery temperature, battery output voltage, or remaining battery capacity is input to the battery control unit 7300 from a battery device including the secondary battery 7310. The battery control unit 7300 performs arithmetic processing using these signals, and controls the temperature adjustment of the secondary battery 7310 or the cooling device provided in the battery device.

  The outside information detection unit 7400 detects information outside the vehicle on which the vehicle control system 7000 is mounted. For example, the outside information detection unit 7400 is connected to at least one of the imaging unit 7410 and the outside information detection unit 7420. The imaging unit 7410 includes at least one of a ToF (Time Of Flight) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. The outside information detection unit 7420 detects, for example, current weather or an environmental sensor for detecting weather, or other vehicles, obstacles, pedestrians, etc. around the vehicle equipped with the vehicle control system 7000. At least one of the surrounding information detection sensors.

  The environmental sensor may be, for example, at least one of a raindrop sensor that detects rainy weather, a fog sensor that detects fog, a sunshine sensor that detects sunlight intensity, and a snow sensor that detects snowfall. The ambient information detection sensor may be at least one of an ultrasonic sensor, a radar device, and a LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) device. The imaging unit 7410 and the outside information detection unit 7420 may be provided as independent sensors or devices, or may be provided as a device in which a plurality of sensors or devices are integrated.

  Here, FIG. 26 shows an example of installation positions of the imaging unit 7410 and the vehicle outside information detection unit 7420. The imaging units 7910, 7912, 7914, 7916, and 7918 are provided at, for example, at least one position of a front nose, a side mirror, a rear bumper, a back door, and an upper part of a windshield in the vehicle 7900. An imaging unit 7910 provided in the front nose and an imaging unit 7918 provided in the upper part of the windshield in the vehicle interior mainly acquire an image in front of the vehicle 7900. Imaging units 7912 and 7914 provided in the side mirror mainly acquire an image of the side of the vehicle 7900. An imaging unit 7916 provided in the rear bumper or the back door mainly acquires an image behind the vehicle 7900. The imaging unit 7918 provided on the upper part of the windshield in the passenger compartment is mainly used for detecting a preceding vehicle or a pedestrian, an obstacle, a traffic light, a traffic sign, a lane, or the like.

  FIG. 26 shows an example of shooting ranges of the respective imaging units 7910, 7912, 7914, and 7916. The imaging range a indicates the imaging range of the imaging unit 7910 provided in the front nose, the imaging ranges b and c indicate the imaging ranges of the imaging units 7912 and 7914 provided in the side mirrors, respectively, and the imaging range d The imaging range of the imaging part 7916 provided in the rear bumper or the back door is shown. For example, by superimposing the image data captured by the imaging units 7910, 7912, 7914, and 7916, an overhead image when the vehicle 7900 is viewed from above is obtained.

  The vehicle outside information detection units 7920, 7922, 7924, 7926, 7928, and 7930 provided on the front, rear, side, corner, and windshield of the vehicle interior of the vehicle 7900 may be ultrasonic sensors or radar devices, for example. The vehicle outside information detection units 7920, 7926, and 7930 provided on the front nose, the rear bumper, the back door, and the windshield in the vehicle interior of the vehicle 7900 may be, for example, LIDAR devices. These outside-vehicle information detection units 7920 to 7930 are mainly used for detecting a preceding vehicle, a pedestrian, an obstacle, and the like.

  Returning to FIG. 25, the description will be continued. The vehicle exterior information detection unit 7400 causes the imaging unit 7410 to capture an image outside the vehicle and receives the captured image data. Further, the vehicle exterior information detection unit 7400 receives detection information from the vehicle exterior information detection unit 7420 connected thereto. When the vehicle exterior information detection unit 7420 is an ultrasonic sensor, a radar device, or a LIDAR device, the vehicle exterior information detection unit 7400 transmits ultrasonic waves, electromagnetic waves, or the like, and receives received reflected wave information. The outside information detection unit 7400 may perform an object detection process or a distance detection process such as a person, a car, an obstacle, a sign, or a character on a road surface based on the received information. The vehicle exterior information detection unit 7400 may perform environment recognition processing for recognizing rainfall, fog, road surface conditions, or the like based on the received information. The vehicle outside information detection unit 7400 may calculate a distance to an object outside the vehicle based on the received information.

  Further, the outside information detection unit 7400 may perform an image recognition process or a distance detection process for recognizing a person, a car, an obstacle, a sign, a character on a road surface, or the like based on the received image data. The vehicle exterior information detection unit 7400 performs processing such as distortion correction or alignment on the received image data, and combines the image data captured by the different imaging units 7410 to generate an overhead image or a panoramic image. Also good. The vehicle exterior information detection unit 7400 may perform viewpoint conversion processing using image data captured by different imaging units 7410.

  The vehicle interior information detection unit 7500 detects vehicle interior information. For example, a driver state detection unit 7510 that detects the driver's state is connected to the in-vehicle information detection unit 7500. Driver state detection unit 7510 may include a camera that captures an image of the driver, a biosensor that detects biometric information of the driver, a microphone that collects sound in the passenger compartment, and the like. The biometric sensor is provided, for example, on a seat surface or a steering wheel, and detects biometric information of an occupant sitting on the seat or a driver holding the steering wheel. The vehicle interior information detection unit 7500 may calculate the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 7510, and determines whether the driver is asleep. May be. The vehicle interior information detection unit 7500 may perform a process such as a noise canceling process on the collected audio signal.

  The integrated control unit 7600 controls the overall operation in the vehicle control system 7000 according to various programs. An input unit 7800 is connected to the integrated control unit 7600. The input unit 7800 is realized by a device that can be input by a passenger, such as a touch panel, a button, a microphone, a switch, or a lever. The integrated control unit 7600 may be input with data obtained by recognizing voice input through a microphone. The input unit 7800 may be, for example, a remote control device using infrared rays or other radio waves, or may be an external connection device such as a mobile phone or a PDA (Personal Digital Assistant) that supports the operation of the vehicle control system 7000. May be. The input unit 7800 may be, for example, a camera. In that case, the passenger can input information using a gesture. Alternatively, data obtained by detecting the movement of the wearable device worn by the passenger may be input. Furthermore, the input unit 7800 may include, for example, an input control circuit that generates an input signal based on information input by a passenger or the like using the input unit 7800 and outputs the input signal to the integrated control unit 7600. A passenger or the like operates the input unit 7800 to input various data or instruct a processing operation to the vehicle control system 7000.

  The storage unit 7690 may include a ROM (Read Only Memory) that stores various programs executed by the microcomputer, and a RAM (Random Access Memory) that stores various parameters, calculation results, sensor values, and the like. The storage unit 7690 may be realized by a magnetic storage device such as an HDD (Hard Disc Drive), a semiconductor storage device, an optical storage device, a magneto-optical storage device, or the like.

  The general-purpose communication I / F 7620 is a general-purpose communication I / F that mediates communication with various devices existing in the external environment 7750. General-purpose communication I / F 7620 is a cellular communication protocol such as GSM (Global System of Mobile communications), WiMAX, LTE (Long Term Evolution) or LTE-A (LTE-Advanced), or a wireless LAN (Wi-Fi (registered trademark)). Other wireless communication protocols such as Bluetooth (registered trademark) may also be implemented. The general-purpose communication I / F 7620 is connected to a device (for example, an application server or a control server) existing on an external network (for example, the Internet, a cloud network, or an operator-specific network) via, for example, a base station or an access point. May be. The general-purpose communication I / F 7620 uses, for example, a P2P (Peer To Peer) technology, a terminal (for example, a driver, a pedestrian or a store terminal, or an MTC (Machine Type Communication) terminal) that exists in the vicinity of the vehicle. You may connect with.

  The dedicated communication I / F 7630 is a communication I / F that supports a communication protocol formulated for use in a vehicle. The dedicated communication I / F 7630 is a standard protocol such as WAVE (Wireless Access in Vehicle Environment), DSRC (Dedicated Short Range Communications), or cellular communication protocol, which is a combination of the lower layer IEEE 802.11p and the upper layer IEEE 1609. May be implemented. The dedicated communication I / F 7630 typically includes vehicle-to-vehicle communication, vehicle-to-vehicle communication, vehicle-to-home communication, and vehicle-to-pedestrian communication. ) Perform V2X communication, which is a concept that includes one or more of the communications.

  The positioning unit 7640 receives, for example, a GNSS signal from a GNSS (Global Navigation Satellite System) satellite (for example, a GPS signal from a GPS (Global Positioning System) satellite), performs positioning, and performs the latitude, longitude, and altitude of the vehicle. The position information including is generated. Note that the positioning unit 7640 may specify the current position by exchanging signals with the wireless access point, or may acquire position information from a terminal such as a mobile phone, PHS, or smartphone having a positioning function.

  For example, the beacon receiving unit 7650 receives radio waves or electromagnetic waves transmitted from a radio station or the like installed on the road, and acquires information such as the current position, traffic jam, closed road, or required time. Note that the function of the beacon receiving unit 7650 may be included in the dedicated communication I / F 7630 described above.

  The in-vehicle device I / F 7660 is a communication interface that mediates connections between the microcomputer 7610 and various in-vehicle devices 7760 present in the vehicle. The in-vehicle device I / F 7660 may establish a wireless connection using a wireless communication protocol such as a wireless LAN, Bluetooth (registered trademark), NFC (Near Field Communication), or WUSB (Wireless USB). The in-vehicle device I / F 7660 is connected to a USB (Universal Serial Bus), HDMI (High-Definition Multimedia Interface), or MHL (Mobile High-definition Link) via a connection terminal (and a cable if necessary). ) Etc. may be established. The in-vehicle device 7760 may include, for example, at least one of a mobile device or a wearable device that a passenger has, or an information device that is carried into or attached to the vehicle. In-vehicle device 7760 may include a navigation device that searches for a route to an arbitrary destination. In-vehicle device I / F 7660 exchanges control signals or data signals with these in-vehicle devices 7760.

  The in-vehicle network I / F 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The in-vehicle network I / F 7680 transmits and receives signals and the like in accordance with a predetermined protocol supported by the communication network 7010.

  The microcomputer 7610 of the integrated control unit 7600 is connected via at least one of a general-purpose communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiving unit 7650, an in-vehicle device I / F 7660, and an in-vehicle network I / F 7680. The vehicle control system 7000 is controlled according to various programs based on the acquired information. For example, the microcomputer 7610 calculates a control target value of the driving force generation device, the steering mechanism, or the braking device based on the acquired information inside and outside the vehicle, and outputs a control command to the drive system control unit 7100. Also good. For example, the microcomputer 7610 realizes ADAS (Advanced Driver Assistance System) functions including collision avoidance or impact mitigation of vehicles, follow-up traveling based on inter-vehicle distance, vehicle speed maintenance traveling, vehicle collision warning, or vehicle lane departure warning. You may perform the cooperative control for the purpose. Further, the microcomputer 7610 controls the driving force generator, the steering mechanism, the braking device, or the like based on the acquired information on the surroundings of the vehicle, so that the microcomputer 7610 automatically travels independently of the driver's operation. You may perform the cooperative control for the purpose of driving.

  The microcomputer 7610 is information acquired via at least one of the general-purpose communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the in-vehicle device I / F 7660, and the in-vehicle network I / F 7680. The three-dimensional distance information between the vehicle and the surrounding structure or an object such as a person may be generated based on the above and local map information including the peripheral information of the current position of the vehicle may be created. Further, the microcomputer 7610 may generate a warning signal by predicting a danger such as a collision of a vehicle, approach of a pedestrian or the like or an approach to a closed road based on the acquired information. The warning signal may be, for example, a signal for generating a warning sound or lighting a warning lamp.

  The audio image output unit 7670 transmits an output signal of at least one of audio and image to an output device capable of visually or audibly notifying information to a vehicle occupant or outside the vehicle. In the example of FIG. 25, an audio speaker 7710, a display unit 7720, and an instrument panel 7730 are illustrated as output devices. Display unit 7720 may include at least one of an on-board display and a head-up display, for example. The display portion 7720 may have an AR (Augmented Reality) display function. In addition to these devices, the output device may be other devices such as headphones, wearable devices such as glasses-type displays worn by passengers, projectors, and lamps. When the output device is a display device, the display device can display the results obtained by various processes performed by the microcomputer 7610 or information received from other control units in various formats such as text, images, tables, and graphs. Display visually. Further, when the output device is an audio output device, the audio output device converts an audio signal made up of reproduced audio data or acoustic data into an analog signal and outputs it aurally.

  In the example shown in FIG. 25, at least two control units connected via the communication network 7010 may be integrated as one control unit. Alternatively, each control unit may be configured by a plurality of control units. Furthermore, the vehicle control system 7000 may include another control unit not shown. In the above description, some or all of the functions of any of the control units may be given to other control units. That is, as long as information is transmitted and received via the communication network 7010, the predetermined arithmetic processing may be performed by any one of the control units. Similarly, a sensor or device connected to one of the control units may be connected to another control unit, and a plurality of control units may transmit / receive detection information to / from each other via the communication network 7010. .

  In the vehicle control system 7000 described above, the solid-state imaging device 1 can be used as an imaging element of the imaging unit 7410. According to the solid-state imaging device 1, when two substrates are stacked and bonded together, the bonding strength can be further improved.

  In addition, this technique can take the following structures.

(1)
A first substrate having a first electrode formed of metal;
A substrate bonded to the first substrate, the second substrate having a second electrode made of metal,
An insulating film is formed on at least one bonding surface of the first substrate and the second substrate with an opening corresponding to the metal bulge during the heat treatment after bonding of the bonding surfaces. Has been
The first electrode and the second electrode are metal-bonded at the opening of the insulating film.
(2)
The width and depth of the opening of the insulating film are adjusted according to the height at which the metal is raised by plastic deformation due to thermal stress during heat treatment. The semiconductor device according to (1).
(3)
The semiconductor device according to (1) or (2), wherein the insulating film is a silicon-based insulating film.
(4)
The semiconductor device according to any one of (1) to (3), wherein the insulating film is formed by stacking a plurality of insulating films made of different materials.
(5)
The width of the opening is different for each of the stacked insulating films. The semiconductor device according to (4).
(6)
The semiconductor device according to (4) or (5), wherein each of the stacked insulating films has a different opening depth depending on the film thickness.
(7)
The metal that forms the first electrode and the second electrode is copper (Cu). The semiconductor device according to any one of (1) to (6).
(8)
The semiconductor device according to any one of (1) to (7),
The first substrate is a sensor substrate having a pixel region in which a plurality of pixels including a photoelectric conversion unit are two-dimensionally arranged,
The second substrate is a circuit board having a predetermined circuit.
(9)
A first substrate having a first electrode made of metal and a second substrate having a second electrode made of metal are bonded together,
By the heat treatment, the metal is raised at the opening formed in the insulating film formed on the bonding surface of at least one of the first substrate and the second substrate, so that the first electrode and the A method for manufacturing a semiconductor device, wherein the second electrode is metal-bonded.
(10)
When the first substrate and the second substrate are bonded together, the width and depth of the opening of the insulating film are adjusted to the height at which the metal is raised by plastic deformation due to thermal stress during heat treatment. The method for manufacturing a semiconductor device according to (9).
(11)
The semiconductor device according to (9) or (10), wherein a silicon-based insulating film is used as a material for the insulating film formed on at least one bonding surface of the first substrate and the second substrate. Manufacturing method.
(12)
The method for manufacturing a semiconductor device according to any one of (9) to (11), wherein a plurality of insulating films made of different materials are stacked when forming the insulating film.
(13)
The method for manufacturing a semiconductor device according to (12), wherein when the plurality of insulating films are stacked, the width of the opening is made different for each of the plurality of stacked insulating films using a difference in etch rate.
(14)
The method for manufacturing a semiconductor device according to (11) or (12), wherein, when the plurality of insulating films are stacked, the depth of the opening varies depending on the film thickness for each of the stacked insulating films. .
(15)
The method for manufacturing a semiconductor device according to any one of (9) to (14), wherein copper (Cu) is used as a metal material for forming the first electrode and the second electrode.

  DESCRIPTION OF SYMBOLS 1 Solid-state imaging device, 11 1st board | substrate, 11S 1st bonding surface, 12 pixels, 13 pixel area | region, 14 pixel drive line, 15 vertical signal line, 21 2nd board | substrate, 21S 2nd bonding surface, 22 vertical drive circuit , 23 column signal processing circuit, 24 horizontal drive circuit, 25 system control circuit, 100, 100-1, 100-2 semiconductor wafer, 101, 101-1, 101-2 oxide film, 103 dummy pad, 104, 104-1 , 104-2 TLV, 105 barrier metal film, 106, 106-1, 106-2 metal film, 107, 107-1, 107-2 insulating film, 108 photoresist, 109, 109-1, 109-2 opening , 110 space, 204, 204-2 TLV, 206, 206-2 metal film, 207, 207-1, 20 7-2 Insulating film, 209, 209-1, 209-2 Opening, 210 space, 304, 304-1, 304-2 TLV, 306, 306-1, 306-2 Metal film, 307, 307-1 Insulating Film, 307a, 307a-1 first insulating film, 307b, 307b-1 second insulating film, 309 opening, 310 space, 1000 imaging device, 1001 solid-state imaging device

Claims (15)

A first substrate having a first electrode formed of metal;
A substrate bonded to the first substrate, the second substrate having a second electrode made of metal,
An insulating film is formed on at least one bonding surface of the first substrate and the second substrate with an opening corresponding to the metal bulge during the heat treatment after bonding of the bonding surfaces. Has been
The first electrode and the second electrode are metal-bonded at the opening of the insulating film. The semiconductor device according to claim 1, wherein the width and depth of the opening of the insulating film are adjusted according to a height at which the metal is raised by plastic deformation due to thermal stress during heat treatment. The semiconductor device according to claim 2, wherein the insulating film is a silicon-based insulating film. The semiconductor device according to claim 3, wherein the insulating film is formed by stacking a plurality of insulating films made of different materials. The semiconductor device according to claim 4, wherein the width of the opening is different for each of the stacked insulating films. The semiconductor device according to claim 5, wherein the depth of the opening differs depending on the film thickness for each of the stacked insulating films. The semiconductor device according to claim 1, wherein a metal forming the first electrode and the second electrode is copper (Cu). The semiconductor device according to claim 1,
The first substrate is a sensor substrate having a pixel region in which a plurality of pixels including a photoelectric conversion unit are two-dimensionally arranged,
The second substrate is a circuit board having a predetermined circuit. A first substrate having a first electrode made of metal and a second substrate having a second electrode made of metal are bonded together,
By the heat treatment, the metal is raised at the opening formed in the insulating film formed on the bonding surface of at least one of the first substrate and the second substrate, so that the first electrode and the A method for manufacturing a semiconductor device, wherein the second electrode is metal-bonded. When the first substrate and the second substrate are bonded together, the width and depth of the opening of the insulating film are adjusted to the height at which the metal is raised by plastic deformation due to thermal stress during heat treatment. A method for manufacturing a semiconductor device according to claim 9. The method for manufacturing a semiconductor device according to claim 10, wherein a silicon-based insulating film is used as a material of the insulating film formed on at least one bonding surface of the first substrate and the second substrate. The method for manufacturing a semiconductor device according to claim 11, wherein a plurality of insulating films made of different materials are stacked when forming the insulating film. The method for manufacturing a semiconductor device according to claim 12, wherein when the plurality of insulating films are stacked, the width of the opening is made different for each of the plurality of stacked insulating films using a difference in etch rate. The method for manufacturing a semiconductor device according to claim 13, wherein when the plurality of insulating films are stacked, the depth of the opening varies depending on the film thickness for each of the stacked insulating films. The method for manufacturing a semiconductor device according to claim 9, wherein copper (Cu) is used as a metal material for forming the first electrode and the second electrode.

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