The present invention relates to a semiconductor device and a method of manufacturing a semiconductor device.
Laminated structures for a semiconductor chip suitable for miniaturization of semiconductor devices have attracted attention. For example, an imager disclosed in Japanese Patent No. 4349232 includes a plurality of laminated substrates and has a pixel array disposed on substantially the entire surface of a first substrate. Recently, further miniaturization of semiconductor chips has been required due to demand for miniaturization of electronic apparatuses.
There are two requirements for laminated semiconductor chips.
First requirement: Bumps (connectors) which connect two semiconductor substrates should be finely formed. Bumps should be arranged at a high density. Short-circuiting of bumps due to collapsing thereof or damage thereto should not occur when two semiconductor substrates are bonded to each other.
Second requirement: Noise caused by a circuit disposed on a second semiconductor substrate should not be superimposed on a signal output from a first semiconductor substrate. For example, noise caused by a circuit disposed on the second substrate should not be superimposed on a signal output from a photoelectric converter disposed on the first semiconductor substrate in a laminated imager.
With respect to the two above-described requirements, technologies disclosed in Japanese Unexamined Patent Application, First Publication No. H6-236981 and Japanese Unexamined Patent Application, First Publication No. 2015-60909 have attempted to seek solutions. Japanese Unexamined Patent Application, First Publication No. H6-236981 discloses a technology for the first requirement. In the technology disclosed in Japanese Unexamined Patent Application, First Publication No. H6-236981, an insulator is disposed between bumps to avoid short-circuiting between the bumps. In the technology disclosed in Japanese Unexamined Patent Application, First Publication No. 2015-60909, a conductor is disposed between two substrates. Accordingly, superimposition of noise caused by a circuit disposed on the second semiconductor substrate on a signal output from the first semiconductor substrate is avoided.
According to a first aspect embodiment of the present invention, a semiconductor device includes a first semiconductor substrate, a second semiconductor substrate, a plurality of connectors, a first insulating part, and a shielding part. The first semiconductor substrate includes a first circuit. The second semiconductor substrate is laminated on the first semiconductor substrate and includes a second circuit. The plurality of connectors are disposed between the first semiconductor substrate and the second semiconductor substrate and electrically connect the first circuit and the second circuit. The first insulating part is disposed around each of connectors included in the plurality of connectors. The shielding part is disposed inside of the first insulating part and formed of a conductor. A void is provided between the connectors and the first insulating part.
According to a second aspect of the present invention, in the first aspect, the shielding part may be electrically insulated from all of the first semiconductor substrate, the second semiconductor substrate, and the plurality of connectors.
According to a third aspect of the present invention, in the first aspect, the shielding part may be electrically connected to only any one of the first semiconductor substrate and the second semiconductor substrate. The shielding part may be connected to a fixed potential in the first semiconductor substrate or the second semiconductor substrate to which the shielding part is connected.
According to a fourth aspect of the present invention, in any one of the first to third aspects, the semiconductor device may further include a plurality of first insulating parts including the first insulating part and a plurality of shielding parts including the shielding part. Gaps may be provided between the plurality of first insulating parts. Gaps may be provided between each of first insulating parts included in the plurality of first insulating parts and each of the connectors.
According to a fifth aspect of the present invention, in the fourth aspect, two or more of the first insulating parts and two or more of the shielding parts may be disposed corresponding to each of the connectors.
According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the shielding part may be electrically connected to only the first semiconductor substrate. Gaps may be provided between the second semiconductor substrate and the first insulating part.
According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the connectors may be formed of a first material. The shielding part may be formed of a second material different from the first material.
According to an eighth aspect of the present invention, in any one of the first to seventh aspects, the thickness of the shielding part in a direction perpendicular to a lamination direction of the first semiconductor substrate and the second semiconductor substrate may be less than the thickness of the connectors in the direction.
According to a ninth aspect of the present invention, a method of manufacturing a semiconductor device includes a first process, a second process, and a third process. A first insulating part is formed around a first region in which each of a plurality of connectors are to be disposed on a first principal plane of a first semiconductor substrate and a shielding part is formed inside of the first insulating part through the first process. The first semiconductor substrate includes a first circuit. The shielding part is formed of a conductor. The plurality of connectors are formed in a second region corresponding to the first region on a second principal plane of a second semiconductor substrate through the second process. The second semiconductor substrate includes a second circuit. The first semiconductor substrate and the second semiconductor substrate are bonded in a state in which the first principal plane and the second principal plane face each other, and a void is provided between connectors included in the plurality of connectors and the first insulating part through the third process. The plurality of connectors are electrically connected to the first circuit and the second circuit.
According to a tenth aspect of the present invention, in the ninth aspect, the method of manufacturing a semiconductor device may further include a fourth process of filling the void with an insulating resin after the first semiconductor substrate and the second semiconductor substrate are bonded.
Embodiments of the present invention will be described with reference to the drawings.
The dimensions of parts which constitute the semiconductor device 1 are not limited to the dimensions shown in
As shown in
The first substrate 10 is formed of a semiconductor material. For example, a semiconductor material forming the first substrate 10 is at least one of silicon (Si) and germanium (Ge). Accordingly, the first substrate 10 is a semiconductor substrate. The first substrate 10 has the plane 100 and a plane 101. The planes 100 and 101 are principal planes of the first substrate 10. The principal planes of the first substrate 10 are relatively large planes among a plurality of planes constituting the surface of the first substrate 10. The plane 100 and the plane 101 face in opposite directions.
The first substrate 10 includes a plurality of first electrodes 11. In
The second substrate 20 is formed of the same semiconductor material as the first substrate 10. Accordingly, the second substrate 20 is a semiconductor substrate. The second substrate 20 has a plane 200 and a plane 201. The planes 200 and 201 are principal planes of the second substrate 20. The principal planes of the second substrate 20 are relatively large planes among a plurality of planes constituting the surface of the second substrate 20. The plane 200 and the plane 201 face in opposite directions. The plane 100 and the plane 201 face each other.
The second substrate 20 includes a plurality of second electrodes 21. In
The connectors 25 are formed of a conductive material. For example, a conductive material forming the connectors 25 is a metal such as gold (Au), silver (Ag) or copper (Cu). The connectors 25 are pillar type structures. The connectors 25 are disposed between the first substrate 10 and the second substrate 20. The connectors 25 are disposed in the first regions R1 and the second regions R2. The connectors 25 are connected to the first electrodes 11 and the second electrodes 21. Accordingly, the connectors 25 are connected to the first substrate 10 and the second substrate 20. The connectors 25 electrically connect the first circuit included in the first substrate 10 and the second circuit included in the second substrate 20.
The shielding part 12 is formed of a conductive material. For example, a conductive material forming the shielding part 12 is a metal such as aluminum (Al) or copper (Cu). The first insulating part 14 is formed of an insulating material (insulator). For example, an insulating material forming the first insulating part 14 is silicon oxide (SiO2). The first insulating part 14 is a wall-shaped structure. The shielding part 12 and the first insulating part 14 are disposed between the first substrate 10 and the second substrate 20. The first insulating part 14 comes into contact with the first substrate 10 and the second substrate 20. The first insulating part 14 may come into contact with only the first substrate 10. That is, gaps may be provided between the first insulating part 14 and the second substrate 20. The shielding part 12 is disposed inside of the first insulating part 14 in a cross section perpendicular to the principle planes of the first substrate 10 and the second substrate 20. That is, the first insulating part 14 covers the shielding part 12. The shielding part 12 and the first insulating part 14 are disposed around the connectors 25. The shielding part 12 shields noise. The first insulating part 14 insulates the shielding part 12.
The second insulating parts 26 are cavities (spaces). The second insulating parts 26 are disposed between the first substrate 10 and the second substrate 20. The second insulating parts 26 are disposed between the connectors 25 and the first insulating part 14. The second insulating parts 26 are not filled with a solid. The connectors 25 do not come into contact with the first insulating part 14. The second insulating parts 26 insulate the connectors 25.
In
An example in which the semiconductor device 1 is an imager (image sensor) will be described in detail.
The pixel part 30 includes a plurality of pixels 31. In
The vertical readout circuit 40 outputs control signals for controlling readout of pixel signals. Accordingly, the vertical readout circuit 40 controls readout of pixel signals from the plurality of pixels 31. The control signals output from the vertical readout circuit 40 are transmitted to the plurality of pixels 31. Pixel signals are simultaneously read out from two or more pixels 31 disposed in the same row in the arrangement of the plurality of pixels 31 according to the control signals.
The plurality of pixels 31 output pixel signals according to the control signals. Each of the plurality of pixels 31 is connected to one connector 25. That is, each of the plurality of connectors 25 is disposed to correspond to each of the plurality of pixels 31. Two or more pixels 31 may be connected to one connector 25. The connectors 25 transmit the pixel signals output from the pixels 31 to the second substrate 20.
The pixels 31 constitute the first circuit disposed on the first substrate 10.
The connectors 25 output the pixel signals output from the plurality of pixels 31 to the second substrate 20. The connectors 25 are connected to the memory unit 50. The memory unit 50 stores the pixel signals output from the plurality of pixels 31. The pixel signals stored in the memory unit 50 are output to the signal processing circuit 60. The signal processing circuit 60 performs signal processing on pixel signals according to control of the horizontal readout circuit 41. For example, the signal processing circuit 60 may perform processing such as noise suppression according to correlated double sampling (CDS).
The horizontal readout circuit 41 reads out the pixel signals processed by the signal processing circuit 60 to a horizontal signal line 80. More specifically, the horizontal readout circuit 41 outputs control signals for controlling signal processing of the signal processing circuit 60 and readout of pixel signals to the signal processing circuit 60. According to such control, pixel signals output from two or more pixels 31 disposed in the same row in the arrangement of the plurality of pixels 31 are sequentially read out to the horizontal signal line 80.
The output unit 70 outputs the pixel signals processed by the signal processing circuit 60 to the outside of the semiconductor device 1. More specifically, the output unit 70 performs processing such as amplification processing on the pixel signals processed by the signal processing circuit 60. The output unit 70 outputs the processed pixel signals to the outside of the semiconductor device 1.
The memory unit 50, the signal processing circuit 60, and the output unit 70 constitute the second circuit disposed on the second substrate 20.
As described above, the semiconductor device 1 includes the first substrate 10 (first semiconductor substrate), the second substrate 20 (second semiconductor substrate), the plurality of connectors 25, the first insulating part 14, the shielding part 12, and the second insulating parts 26. The first substrate 10 includes the first circuit. The second substrate 20 is laminated on the first substrate 10 and includes the second circuit. The plurality of connectors 25 are disposed between the first substrate 10 and the second substrate 20 and electrically connect the first circuit and the second circuit. The first insulating part 14 is disposed around each of the plurality of connectors 25. The shielding part 12 is disposed inside of the first insulating part 14 and is formed of a conductor. The second insulating parts 26 are disposed between the connectors 25 and the first insulating part 14.
Positional displacement may occur in the connectors 25 or the first insulating part 14 when the connectors 25 or the first insulating part 14 are formed. Positional displacement between the first substrate 10 and the second substrate 20 may occur when the first substrate 10 and the second substrate 20 are bonded to each other. According to such positional displacement, there is a likelihood of the connectors 25 coming into contact with the first insulating part 14. However, since the shielding part 12 is surrounded by the first insulating part 14, the connectors 25 do not come into contact with the shielding part 12. Accordingly, the likelihood of short-circuiting of the connectors 25 decreases. Since the shielding part 12 is disposed between the first substrate 10 and the second substrate 20, noise which is superimposed on a signal output from the first substrate 10 and is caused by the second circuit disposed on the second substrate 20 is reduced. That is, signal deterioration due to noise is reduced.
A method of manufacturing the semiconductor device 1 will be described with reference to
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As described above, the method of manufacturing the semiconductor device 1 includes a first process (
A semiconductor device of each embodiment of the present invention need not include a component corresponding to at least one of the first electrodes 11 and the second electrodes 21. The semiconductor device of each embodiment of the present invention need not include circuits other than the first circuit and the second circuit electrically connected to each other through the connectors 25. The semiconductor device of each embodiment of the present invention may be a device other than an imager. A method of manufacturing a semiconductor device of each embodiment of the present invention need not include processes other than the above-described first to third processes.
In the semiconductor device 1 and the method of manufacturing the same according to the first embodiment, the first insulating part 14 is disposed to decrease the likelihood of short-circuiting of the connectors 25. The shielding part 12 is disposed to reduce signal deterioration due to noise.
The shielding part 12 may be electrically insulated from all of the first substrate 10, the second substrate 20, and the plurality of connectors 25. When the shielding part 12 is floating, it is not necessary to form a structure for connecting the shielding part 12 to a fixed potential. Accordingly, the shielding part 12 may be miniaturized. As a result, the spacing of the connectors 25 may be reduced. Therefore, densification of the connectors 25 is realized.
The connectors 25 may be formed of a first material and the shielding part 12 may be formed of a second material different from the first material. That is, the connectors 25 and the shielding part 12 may be formed of different materials. When the shielding part 12 is formed of a material on which fine processing is easily performed, the area occupied by the first insulating part 14 is reduced. Accordingly, densification of the connectors 25 is realized.
Since a void is provided between the connectors 25 and the first insulating part 14, manufacturing costs of the semiconductor device 1 can be decreased as compared to manufacturing costs when a resin is filled into the void. In the semiconductor device 1, separation of the connectors 25 from the first substrate 10 or the second substrate 20 according to expansion of the resin is avoided.
In the semiconductor device 1a, the second insulating parts 26 in the semiconductor device 1 shown in
The semiconductor device 1a includes a plurality of first insulating parts 14 and a plurality of shielding parts 12. Gaps are provided between the plurality of first insulating parts 14. Gaps are provided between each of the plurality of first insulating parts 14 and each of the plurality of connectors 25. That is, gaps are provided between two neighboring first insulating parts 14. The plurality of first insulating parts 14 are separated from each other. Each of the plurality of first insulating parts 14 and each of the connectors 25 are separated from each other. The second insulating part 26a is disposed in the gaps therebetween. Each of the plurality of shielding parts 12 is disposed inside of one of the plurality of first insulating parts 14.
The thickness of the connectors 25 is D2a. The thickness D2a is a width in the direction Dr2 perpendicular to the lamination direction Dr1 of the first substrate 10 and the second substrate 20. The thickness D2a is greater than the thickness D2 (
With respect to points other than the above, the configuration shown in
Two or more first insulating parts 14 and two or more shielding parts 12 are disposed corresponding to each of the plurality of connectors 25. That is, two or more first insulating parts 14 and two or more shielding parts 12 are disposed around one connector 25. As shown in
The thickness D3 of the shielding parts 12 in the direction Dr2 perpendicular to the lamination direction Dr1 of the first substrate 10 and the second substrate 20 is less than the thickness D2a of the connectors 25 in the direction Dr2.
With respect to points other than the above, the configuration shown in
A method of manufacturing the semiconductor device 1a includes the processes shown in
A void is provided around the first insulating parts 14 and the connectors 25 through the process shown in
The method of manufacturing the semiconductor device 1a includes a fourth process in addition to the first to third processes. After the first substrate 10 and the second substrate 20 are bonded, an insulating resin is filled into the void in the fourth process.
In the semiconductor device 1a, the thickness D3 of the shielding parts 12 may be equal to or greater than the thickness D2a of the connectors 25. In the semiconductor device 1 shown in
The spacing of the connectors 25 may be reduced by causing the thickness D3 of the shielding parts 12 to be less than the thickness D2a of the connectors 25. Accordingly, densification of the connectors 25 is realized. Otherwise, the thickness D2a of the connectors 25 may be increased by causing the thickness D3 of the shielding parts 12 to be less than the thickness D2a of the connectors 25. Accordingly, reliability of connection between the first substrate 10 and the second substrate 20 and the connectors 25 is improved.
The plurality of first insulating parts 14 are disposed to form a resin injection path between the plurality of first insulating parts 14. Since it is difficult for a void to be generated when the resin is filled in, the second insulating part 26a is easily formed.
Since the second insulating part 26a is disposed, separation of the connectors 25 from the first substrate 10 or the second substrate 20 due to an impact applied to the semiconductor device 1a from outside is reduced.
In the semiconductor device 2, the first substrate 10 in the semiconductor device 1a shown in
The first substrate 10a includes a plurality of first electrodes 11 and a plurality of third electrodes 17. In
The shielding part 12 is electrically connected to only any one of the first substrate 10a and the second substrate 20. The shielding part 12 is connected to a fixed potential in the first substrate 10a or the second substrate 20 to which the shielding part 12 is connected.
In the semiconductor device 2 shown in
The thickness of the connectors 25 in
With respect to points other than the above, the configuration shown in
The shielding part 12 is connected to a fixed potential and thus a shielding effect with respect to noise is improved.
In the semiconductor device 3, the first substrate 10a in the semiconductor device 2 shown in
The first substrate 10a in the semiconductor device 2 shown in
The shielding part 12 is electrically connected to only any one of the first substrate 10b and the second substrate 20. Gaps are provided between a semiconductor substrate different from a semiconductor substrate connected to the shielding part 12, among the first substrate 10b and the second substrate 20, and the first insulating part 14.
In the semiconductor device 3 shown in
With respect to points other than the above, the configuration shown in
The gaps between the first insulating part 14 and the second substrate 20 become a resin injection path. Accordingly, a plurality of first insulating parts 14 need not be disposed. When the shielding part 12 is connected to a fixed potential, a plurality of third electrodes 17 need not be disposed. Accordingly, it is possible to reduce the spacing of the first electrodes 11, that is, the spacing of the connectors 25. Therefore, densification of the connectors 25 is realized.
While preferred embodiments of the invention have been described and shown above, it should be understood that these are exemplars of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.
The present application is a continuation application based on international patent application PCT/JP 2016/061533, filed on Apr. 8, 2016, the content of which is incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/JP2016/061533 | Apr 2016 | US |
Child | 16129072 | US |