Solid-state camera

Abstract

The purpose of the present disclosure is to provide a solid-state imaging device capable of suppressing image quality degradation. The solid-state imaging device includes: a first pixel having a plurality of on-chip lenses and a plurality of photoelectric conversion units that share a first color filter; a second pixel that is arranged adjacent to the first pixel and has a plurality of on-chip lenses and a plurality of photoelectric conversion units that share a second color filter; and a first light shielding area that is provided between the first pixel and the second pixel.

Description

Technical Field

[0001] The present disclosure relates to a solid-state imaging device having a photoelectric conversion unit that converts incident light into an electric signal. Background Art

[0002] There is known a Quad Bayer coding in which one pixel is composed of sub-pixels arranged in two rows and two columns (for example, Patent Document 1).

[0003] Reference List

[0004] Patent Literature

[0005] Patent Document 1: JP 2011-239070 A Summary of the invention

[0006] Technical issues

[0007] Compared with a common structure in which one pixel is composed of one photoelectric conversion element, the problem of quad Bayer encoding is that the image quality deteriorates due to flare and color mixing due to the deterioration of oblique incidence characteristics. In particular, in a large-size type solid-state camera, the image quality deteriorates significantly due to the deterioration of oblique incidence characteristics because the chip size is large. In addition, in a honeycomb type, the image quality deteriorates significantly due to the deterioration of oblique incidence characteristics because pupil correction is strongly applied at high image heights.

[0008] An object of the present disclosure is to provide a solid-state imaging device capable of suppressing degradation of image quality.

[0009] Technical solutions to the problem

[0010] In order to achieve the above-mentioned purpose, a solid-state imaging device according to an aspect of the present disclosure includes: a first pixel, which has a plurality of on-chip lenses and a plurality of photoelectric conversion units that share a first color filter with each other; a second pixel, which is arranged adjacent to the first pixel and has a plurality of on-chip lenses and a plurality of photoelectric conversion units that share a second color filter with each other; and a first light-shielding area, which is arranged between the first pixel and the second pixel. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] [ Figure 1 ]

[0012] Figure 1 : is a block diagram showing an example of a schematic configuration of a solid-state imaging device according to each embodiment of the present disclosure.

[0013] [ Figure 2 ]

[0014] Figure 2: is a plan view showing an example of a schematic configuration of a pixel provided in the solid-state image pickup device according to the first embodiment of the present disclosure.

[0015] [ Figure 3 ]

[0016] Figure 3 is a cross-sectional view showing an example of a schematic configuration of a pixel provided in the solid-state image pickup device according to the first embodiment of the present disclosure.

[0017] [ Figure 4 ]

[0018] Figure 4 : is a diagram showing the effect of the solid-state imaging device according to the first embodiment of the present disclosure.

[0019] [ Figure 5 ]

[0020] Figure 5 is a cross-sectional view showing an example of a schematic configuration of a pixel provided in a solid-state image pickup device according to a second embodiment of the present disclosure.

[0021] [ Figure 6 ]

[0022] Figure 6 is a cross-sectional view showing an example of a schematic configuration of a pixel provided in a solid-state image pickup device according to a third embodiment of the present disclosure.

[0023] [ Figure 7 ]

[0024] Figure 7 is a cross-sectional view showing an example of a schematic configuration of a pixel provided in a solid-state image pickup device according to a fourth embodiment of the present disclosure.

[0025] [ Figure 8 ]

[0026] Figure 8 : is a diagram schematically showing a cross section of a green pixel and a blue pixel provided in a solid-state image pickup device according to a fourth embodiment of the present disclosure.

[0027] [ Fig. 9 ]

[0028] Fig. 9 is a diagram showing a solid-state image pickup device according to a fourth embodiment of the present disclosure and is a graph showing a relationship between a line width of optical black and color mixing resistance of a pixel.

[0029] [ Fig.10 ]

[0030] Fig.101 is a diagram showing a solid-state image pickup device according to a fourth embodiment of the present disclosure and is a graph (first part) showing a measured result of an oblique incidence characteristic of a central portion of a pixel region represented by an image height.

[0031] [ Fig.11 ]

[0032] Fig.11 1 is a diagram showing a solid-state image pickup device according to a fourth embodiment of the present disclosure and is a graph (second part) showing a measured result of an oblique incidence characteristic of a central portion of a pixel region represented by an image height.

[0033] [ Fig.12 ]

[0034] Fig.12 1 is a diagram showing a solid-state image pickup device according to a fourth embodiment of the present disclosure and is a graph (first part) showing a measured result of an oblique incidence characteristic of an end portion in the longitudinal direction of a pixel region represented by an image height.

[0035] [ Fig.13 ]

[0036] Fig.13 1 is a diagram showing a solid-state image pickup device according to a fourth embodiment of the present disclosure and is a graph (second part) showing a measured result of an oblique incidence characteristic of an end portion in the longitudinal direction of a pixel region represented by an image height.

[0037] [ Fig.14 ]

[0038] Fig.14 is a diagram showing a solid-state image pickup device according to a fourth embodiment of the present disclosure and is a graph showing actual measurement results of LCR of a central portion of a pixel region represented by image height.

[0039] [ Fig.15 ]

[0040] Fig.15 is a diagram showing a solid-state image pickup device according to a fourth embodiment of the present disclosure and is a graph showing actual measurement results of LCR of an end portion in the longitudinal direction of a pixel region represented by image height.

[0041] [ Fig.16 ]

[0042] Fig.16 is a cross-sectional view showing an example of a schematic configuration of a pixel provided in a solid-state image pickup device according to a fifth embodiment of the present disclosure.

[0043] [ Fig.17 ]

[0044] Fig.17: is a diagram showing the effect of the solid-state imaging device according to the fifth embodiment of the present disclosure.

[0045] [ Fig.18 ]

[0046] Fig.18 is a diagram schematically showing an example of a cross section of a schematic configuration of a pixel provided in a solid-state image pickup device according to a sixth embodiment of the present disclosure.

[0047] [ Fig.19 ]

[0048] Fig.19 : is a plan view showing an example of a schematic configuration of a pixel provided in a solid-state image pickup device according to a seventh embodiment of the present disclosure.

[0049] [ Fig. 20 ]

[0050] Fig. 20 : is a plan view showing an example of a schematic configuration of a pixel provided in a solid-state image pickup device according to an eighth embodiment of the present disclosure. DETAILED DESCRIPTION

[0051] Hereinafter, a mode (embodiment) for carrying out the present disclosure will be described in detail with reference to the accompanying drawings. The following description is a specific example of the present disclosure, and the present disclosure is not limited to the following aspects.

[0052] [First embodiment]

[0053] Will refer to Figures 1 to 4 A solid-state imaging device according to a first embodiment of the present disclosure will be described. First, an overall schematic configuration of a solid-state imaging device according to the present embodiment will be described, and then a configuration of a pixel provided in the solid-state imaging device will be described.

[0054] <Overall Structure of Solid-State Image Pickup Device>

[0055] like Figure 1 As shown, the solid-state imaging device 1a of this embodiment includes: a pixel area 3 having a plurality of pixels 2 arranged on a supporting substrate 11 formed of silicon, a vertical drive circuit 4, a column signal processing circuit 5, a horizontal drive circuit 6, an output circuit 7 and a control circuit 8, etc.

[0056] For example, each pixel 2 has a photoelectric conversion unit, which is composed of a photodiode and a plurality of pixel transistors. A plurality of pixels 2 are regularly arranged in a two-dimensional array on a support substrate 11. The pixel transistors constituting the pixel 2 may be four MOS transistors consisting of a transfer transistor, a reset transistor, a selection transistor, and an amplification transistor (all not shown), or may be three transistors other than the selection transistor.

[0057] The pixel area 3 has a plurality of pixels 2 regularly arranged in a two-dimensional array. The pixel area 3 has: an effective pixel area, in which light is actually received and a signal charge generated by photoelectric conversion is amplified to be read by the column signal processing circuit 5; and a black reference pixel area (not shown) for outputting optical black used as a black level reference. The black reference pixel area is formed, for example, in the periphery of the effective pixel area.

[0058] The control circuit 8 generates a clock signal and a control signal, etc., which are operation references of the vertical drive circuit 4, the column signal processing circuit 5, the horizontal drive circuit 6, etc., based on the vertical synchronization signal, the horizontal synchronization signal, and the main clock. The clock signal and the control signal, etc. generated by the control circuit 8 are input to the vertical drive circuit 4, the column signal processing circuit 5, the horizontal drive circuit 6, etc.

[0059] For example, the vertical drive circuit 4 is composed of a shift register. The vertical drive circuit 4 outputs a selection signal to the selection signal line 9b in a row unit, and selectively scans a plurality of pixels 2 arranged in the pixel area 3 sequentially in the vertical direction. Although not shown, the vertical drive circuit 4 outputs a reset signal to a reset signal line arranged in parallel with the selection signal line 9b, and sequentially resets a plurality of pixels 2 in the vertical direction in a row unit. Therefore, a pixel signal based on a signal charge corresponding to the intensity of received light generated in a photodiode of each of the plurality of pixels 2 is provided to the column signal processing circuit 5 through the vertical signal line.

[0060] For example, the column signal processing circuit 5 is arranged for each column of the pixel 2, and for each pixel column, uses a signal from a black reference pixel area (not shown, but formed around the effective pixel area) to perform signal processing such as noise removal and signal amplification on a signal output from one row of pixels 2 via the vertical signal line 9a. A horizontal selection switch (not shown) is provided between the output stage of the column signal processing circuit 5 and the horizontal signal line 10.

[0061] The horizontal driving circuit 6 is constituted by a shift register, for example, and sequentially outputs horizontal scanning pulses, thereby sequentially selecting each column signal processing circuit 5 , and outputting a pixel signal from each column signal processing circuit 5 to the horizontal signal line 10 .

[0062] The output circuit 7 processes the signals sequentially supplied from the column signal processing circuits 5 through the horizontal signal line 10 and outputs the signals.

[0063] <Configuration of Pixel Provided in Solid-State Image Capture Device>

[0064] The solid-state imaging device 1a according to the present embodiment will be described taking a back-illuminated CMOS type solid-state imaging device as an example. The solid-state imaging device 1a has a pixel structure in which so-called four-pixel sharing is set as one unit, in which four photoelectric conversion units share necessary pixel transistors with each other. Figure 2 is a diagram showing the extraction of the pixels arranged in the pixel area 3 (see Figure 1 ) is a plan view of an example of a schematic configuration of adjacent four pixels 2 among a plurality of pixels 2. Figure 3 : is a cross-sectional view showing an example of a schematic configuration of adjacent green sub-pixels and two blue sub-pixels (the details of the sub-pixels will be described later). Figure 4 : is a diagram showing the effect of the solid-state imaging device according to the first embodiment of the present disclosure.

[0065] like Figure 2 and Figure 3 As shown, the solid-state imaging device 1a has a plurality of (four in the present embodiment) on-chip lenses 23G and a plurality of (four in the present embodiment) photoelectric conversion units 21G (an example of a first photoelectric conversion unit) that share a green filter (an example of a first color filter) 22G with each other. The plurality of on-chip lenses 23G are arranged on one side of the green filter 22G, and the plurality of photoelectric conversion units 21G are arranged on the other side of the green filter 22G. One side of the green filter 22G is the back side of the solid-state imaging device 1a, and is also the light incident side where light enters from the outside. The other side of the green filter 22G is the front side of the solid-state imaging device 1a, and is also the opposite side of the light incident side.

[0066] The solid-state imaging device 1a has a blue sub-pixel (an example of a second sub-pixel) 20B, and the blue sub-pixel 20B has a plurality of (four in the present embodiment) on-chip lenses 23B and a plurality of (four in the present embodiment) photoelectric conversion units 21B (an example of a second photoelectric conversion unit) arranged adjacent to a green filter 22G and sharing a blue filter (an example of a second color filter) 22B with each other. The plurality of on-chip lenses 23B are arranged on one side of the blue filter 22B, and the plurality of photoelectric conversion units 21B are arranged on the other side of the blue filter 22B. One side of the blue filter 22B is the back side of the solid-state imaging device 1a, and is also the light incident side from which light enters from the outside. The other side of the blue filter 22B is the front side of the solid-state imaging device 1a, and is also the opposite side of the light incident side.

[0067] like Figure 2As shown, the solid-state imaging device 1a has a plurality of (four in the present embodiment) on-chip lenses 23R and a plurality of (four in the present embodiment) photoelectric conversion units 21R (an example of a second photoelectric conversion unit) arranged adjacent to a green filter 22G and sharing a red filter (an example of a second color filter) 22R with each other. The plurality of on-chip lenses 23R are arranged on one side of the red filter 22R, and the plurality of photoelectric conversion units 21R are arranged on the other side of the red filter 22R. One side of the red filter 22R is the back side of the solid-state imaging device 1a, and is also the light incident side where light enters from the outside. The other side of the red filter 22R is the front side of the solid-state imaging device 1a, and is also the opposite side of the light incident side.

[0068] In the following, in the case where the red pixel 2R, the green pixel 2G, and the blue pixel 2B are not described in a differentiated manner, they are collectively referred to as "pixels 2". Looking at four adjacent pixels 2, two green pixels 2G are arranged diagonally, and red pixels 2R and blue pixels 2B are arranged diagonally. In the pixel area 3 of the solid-state imaging device 1a, each pixel having one red pixel 2R, two green pixels 2G, and one blue pixel 2B as a unit is arranged side by side in the vertical direction and the horizontal direction. That is, the red pixel 2R, the green pixel 2G, and the blue pixel 2B are arranged in the Bayer array in the pixel area 3.

[0069] like Figure 2 and Figure 3 As shown, the solid-state imaging device 1a has a first light shielding region 31 provided between the green pixel 2G and the blue pixel 2B. In addition, the solid-state imaging device 1a has a first light shielding region 31 provided between the green pixel 2G and the red pixel 2R. The first light shielding region 31 is provided to span the green pixel 2G and the blue pixel 2B between the green filter 22G and the photoelectric conversion unit 21G and between the blue filter 22B and the photoelectric conversion unit 21B, and is provided along the boundary between the green pixel 2G and the blue pixel 2B. In addition, the first light shielding region 31 is provided to span the green pixel 2G and the red pixel 2R between the green filter 22G and the photoelectric conversion unit 21G and between the red filter 22R and the photoelectric conversion unit 21R, and is provided along the boundary between the green pixel 2G and the red pixel 2R.

[0070] As a result, when focusing on a unit of a red pixel 2R, two green pixels 2G and one blue pixel 2B, the first light shielding area 31 is arranged in a cross shape in the unit. By the way, the green pixel 2G is sandwiched between the blue pixels 2B in the direction in which the vertical signal line 9a is arranged. By the way, the green pixel 2G is sandwiched between the red pixels 2R in the direction in which the selection signal line 9b is arranged. Therefore, when focusing on a unit of a red pixel 2R, two green pixels 2G and one blue pixel 2B, the first light shielding area 31 is arranged in a manner that surrounds the unit. As described above, when focusing on a unit of a red pixel 2R, two green pixels 2G and one blue pixel 2B, the first light shielding area 31 is arranged in a lattice shape.

[0071] like Figure 2 and Figure 3 As shown, the green pixel 2G has: a green sub-pixel 20Ga (an example of a first sub-pixel) having a photoelectric conversion unit 21Ga (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21G, a green sub-pixel 20Gd (an example of a first sub-pixel) having a photoelectric conversion unit 21Gd (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21G, a green sub-pixel 20Gb (an example of a second sub-pixel) having a photoelectric conversion unit 21Gb (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21G, and a green sub-pixel 20Gc (an example of a second sub-pixel) having a photoelectric conversion unit 21Gc (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21G. In the following, when the green sub-pixel 20Ga, the green sub-pixel 20Gb, the green sub-pixel 20Gc, and the green sub-pixel 20Gd are not described in distinction, they are collectively referred to as "green sub-pixels 20G". Furthermore, in the case where the photoelectric conversion unit 21Ga, the photoelectric conversion unit 21Gb, the photoelectric conversion unit 21Gc, and the photoelectric conversion unit 21Gd are described without distinction, they are collectively referred to as “photoelectric conversion unit 21G”.

[0072] The green pixel 2G has a second light shielding area 32 disposed between the green sub-pixel 20Ga and the photoelectric conversion unit 21Gb. The green pixel 2G has a second light shielding area 32 disposed between the green sub-pixel 20Ga and the photoelectric conversion unit 21Gc. The green pixel 2G has a second light shielding area 32 disposed between the green sub-pixel 20Gd and the photoelectric conversion unit 21Gb. The green pixel 2G has a second light shielding area 32 disposed between the green sub-pixel 20Gd and the photoelectric conversion unit 21Gc. The width of the second light shielding area 32 disposed in the green pixel 2G is narrower than the width of the first light shielding area 31.

[0073] The second light shielding region 32 provided in the green pixel 2G is provided between the green filter 22G and the photoelectric conversion unit 21Ga and the photoelectric conversion unit 21Gb adjacent to each other, between the green filter 22G and the photoelectric conversion unit 21Gb and the photoelectric conversion unit 21Gd adjacent to each other, between the green filter 22G and the photoelectric conversion unit 21Gd and the photoelectric conversion unit 21Gc adjacent to each other, and between the green filter 22G and the photoelectric conversion unit 21Gc and the photoelectric conversion unit 21Ga adjacent to each other. The second light shielding region 32 is provided along each of the boundary between the photoelectric conversion unit 21Ga and the photoelectric conversion unit 21Gb adjacent to each other, the boundary between the photoelectric conversion unit 21Gb and the photoelectric conversion unit 21Gd adjacent to each other, the boundary between the photoelectric conversion unit 21Gd and the photoelectric conversion unit 21Gc adjacent to each other, and the boundary between the photoelectric conversion unit 21Gc and the photoelectric conversion unit 21Ga adjacent to each other. The second light shielding region 32 is provided across the mutually adjacent photoelectric conversion unit 21Ga and the photoelectric conversion unit 21Gb, across the mutually adjacent photoelectric conversion unit 21Gb and the photoelectric conversion unit 21Gd, across the mutually adjacent photoelectric conversion unit 21Gd and the photoelectric conversion unit 21Gc, and across the mutually adjacent photoelectric conversion unit 21Gc and the photoelectric conversion unit 21Ga.

[0074] The blue pixel 2B has a blue sub-pixel 20Ba having a photoelectric conversion unit 21Ba among the plurality of photoelectric conversion units 21B, a blue sub-pixel 20Bd having a photoelectric conversion unit 21Bd among the plurality of photoelectric conversion units 21B, a blue sub-pixel 20Bb having a photoelectric conversion unit 21Bb among the plurality of photoelectric conversion units 21B, and a blue sub-pixel 20Bc having a photoelectric conversion unit 21Bc among the plurality of photoelectric conversion units 21B. Hereinafter, in the case where the blue sub-pixel 20Ba, the blue sub-pixel 20Bb, the blue sub-pixel 20Bc, and the blue sub-pixel 20Bd are not described in distinction, they are collectively referred to as "blue sub-pixel 20B". In addition, in the case where the photoelectric conversion unit 21Ba, the photoelectric conversion unit 21Bb, the photoelectric conversion unit 21Bc, and the photoelectric conversion unit 21Bd are not described in distinction, they are collectively referred to as "photoelectric conversion unit 21B".

[0075] The blue pixel 2B has a second light shielding region 32 disposed between the blue sub-pixel 20Ba and the photoelectric conversion unit 21Bb. The blue pixel 2B has a second light shielding region 32 disposed between the blue sub-pixel 20Ba and the photoelectric conversion unit 21Bc. The blue pixel 2B has a second light shielding region 32 disposed between the blue sub-pixel 20Bd and the photoelectric conversion unit 21Bb. The blue pixel 2B has a second light shielding region 32 disposed between the blue sub-pixel 20Bd and the photoelectric conversion unit 21Bc. The width of the second light shielding region 32 disposed in the blue pixel 2B is narrower than the width of the first light shielding region 31.

[0076] The second light shielding region 32 provided in the blue pixel is provided between the blue filter 22B and the photoelectric conversion unit 21Ba and the photoelectric conversion unit 21Bb adjacent to each other, between the blue filter 22B and the photoelectric conversion unit 21Bb and the photoelectric conversion unit 21Bd adjacent to each other, between the blue filter 22B and the photoelectric conversion unit 21Bd and the photoelectric conversion unit 21Bc adjacent to each other, and between the blue filter 22B and the photoelectric conversion unit 21Bc and the photoelectric conversion unit 21Ba adjacent to each other. The second light shielding region 32 is provided along each of the boundary between the photoelectric conversion unit 21Ba and the photoelectric conversion unit 21Bb adjacent to each other, the boundary between the photoelectric conversion unit 21Bb and the photoelectric conversion unit 21Bd adjacent to each other, the boundary between the photoelectric conversion unit 21Bd and the photoelectric conversion unit 21Bc adjacent to each other, and the boundary between the photoelectric conversion unit 21Bc and the photoelectric conversion unit 21Ba adjacent to each other. The second light shielding region 32 is provided across the photoelectric conversion unit 21Ba and the photoelectric conversion unit 21Bb adjacent to each other, across the photoelectric conversion unit 21Bb and the photoelectric conversion unit 21Bd adjacent to each other, across the photoelectric conversion unit 21Bd and the photoelectric conversion unit 21Bc adjacent to each other, and across the photoelectric conversion unit 21Bc and the photoelectric conversion unit 21Ba adjacent to each other.

[0077] The red pixel 2R includes a red sub-pixel 20Ra including a photoelectric conversion unit 21Ra among the plurality of photoelectric conversion units 21R, a red sub-pixel 20Rd including a photoelectric conversion unit 21Rd among the plurality of photoelectric conversion units 21R, a red sub-pixel 20Rb including a photoelectric conversion unit 21Rb among the plurality of photoelectric conversion units 21R, and a red sub-pixel 20Rc including a photoelectric conversion unit 21Rc among the plurality of photoelectric conversion units 21R. Hereinafter, in the case where the red sub-pixel 20Ra, the red sub-pixel 20Rb, the red sub-pixel 20Rc, and the red sub-pixel 20Rd are described without distinction, they are collectively referred to as “red sub-pixel 20R”. In addition, in the case where the photoelectric conversion unit 21Ra, the photoelectric conversion unit 21Rb, the photoelectric conversion unit 21Rc, and the photoelectric conversion unit 21Rd are described without distinction, they are collectively referred to as “photoelectric conversion unit 21R”.

[0078] The red pixel 2R has a second light shielding region 32 disposed between the red sub-pixel 20Ra and the photoelectric conversion unit 21Rb. The red pixel 2R has a second light shielding region 32 disposed between the red sub-pixel 20Ra and the photoelectric conversion unit 21Rc. The red pixel 2R has a second light shielding region 32 disposed between the red sub-pixel 20Rd and the photoelectric conversion unit 21Rb. The red pixel 2R has a second light shielding region 32 disposed between the red sub-pixel 20Rd and the photoelectric conversion unit 21Rc. The width of the second light shielding region 32 disposed in the red pixel 2R is narrower than the width of the first light shielding region 31.

[0079] The second light shielding region 32 provided in the red pixel is provided between the red filter 22R and the photoelectric conversion unit 21Ra and the photoelectric conversion unit 21Rb adjacent to each other, between the red filter 22R and the photoelectric conversion unit 21Rb and the photoelectric conversion unit 21Rd adjacent to each other, between the red filter 22R and the photoelectric conversion unit 21Rd and the photoelectric conversion unit 21Rc adjacent to each other, and between the red filter 22R and the photoelectric conversion unit 21Rc and the photoelectric conversion unit 21Ra adjacent to each other. The second light shielding region 32 is provided along each of the boundary between the photoelectric conversion unit 21Ra and the photoelectric conversion unit 21Rb adjacent to each other, the boundary between the photoelectric conversion unit 21Rb and the photoelectric conversion unit 21Rd adjacent to each other, the boundary between the photoelectric conversion unit 21Rd and the photoelectric conversion unit 21Rc adjacent to each other, and the boundary between the photoelectric conversion unit 21Rc and the photoelectric conversion unit 21Ra adjacent to each other. The second light shielding region 32 is provided across the mutually adjacent photoelectric conversion unit 21Ra and the photoelectric conversion unit 21Rb, across the mutually adjacent photoelectric conversion unit 21Rb and the photoelectric conversion unit 21Rd, across the mutually adjacent photoelectric conversion unit 21Rd and the photoelectric conversion unit 21Rc, and across the mutually adjacent photoelectric conversion unit 21Rc and the photoelectric conversion unit 21Ra.

[0080] The second light shielding area 32 is arranged in a cross shape in each of the red pixel 2R, the green pixel 2G, and the blue pixel 2B. When viewed from a direction orthogonal to the red pixel 2R, the four red sub-pixels 20R are separated from each other by the second light shielding area 32. Similarly, when viewed from a direction orthogonal to the green pixel 2G, the four green sub-pixels 20G are separated from each other by the second light shielding area 32. Similarly, when viewed from a direction orthogonal to the blue pixel 2B, the four blue sub-pixels 20B are separated from each other by the second light shielding area 32.

[0081] For example, the first light shielding region 31 and the second light shielding region 32 are formed integrally. As a result, in each of the red pixel 2R, the green pixel 2G, and the blue pixel 2B, a lattice-shaped light shielding region is arranged by the first light shielding region 31 and the second light shielding region 32. The first light shielding region 31 and the second light shielding region 32 are formed in a lattice shape so that each of the four photoelectric conversion units 21R, the four photoelectric conversion units 21G, and the four photoelectric conversion units 21B is opened. The first light shielding region 31 and the second light shielding region 32 can be formed of a light shielding material. As a forming material of the first light shielding region 31 and the second light shielding region 32, for example, tungsten (W), aluminum (Al), or copper (Cu) can be used.

[0082] like Figure 3As shown, the solid-state imaging device 1a has: a substrate 12 having a plurality of pixels 2, a wiring layer 13 formed on the front side of the substrate 12, and a support substrate 11. In addition, the solid-state imaging device 1a has a pixel separation portion 26 formed in a manner surrounding a portion of the periphery of the photoelectric conversion units 21R, 21G, and 21B. In addition, the solid-state imaging device 1a includes an insulating film 24 formed on the back side (i.e., the light incident side) of the substrate 12 in a manner covering the pixel separation portion 26 and the photoelectric conversion units 21R, 21G, and 21B, and a planarization film 25 formed in a manner covering the insulating film 24, the first light shielding region 31, and the second light shielding region 32. The red filter 22R, the green filter 22G, and the blue filter 22B provided in the solid-state imaging device 1a are arranged on the back side (i.e., the light incident side) of the planarization film 25. The on-chip lenses 23R, 23G and 23B provided in the solid-state imaging device 1a are arranged to correspond to the red sub-pixel 20R, green sub-pixel 20G and blue sub-pixel 20B on the back side (i.e., the light incident side) of the red filter 22R, green filter 22G and blue filter 22B, respectively.

[0083] The substrate 12 is made of a semiconductor substrate formed of silicon, and its thickness is, for example, 1 μm to 6 μm. Figure 1 ), a plurality of pixels 2 each having a photoelectric conversion unit 21R, 21G, and 21B and a plurality of pixel transistors (details will be described later) constituting a pixel circuit unit are formed in a two-dimensional matrix. The photoelectric conversion units 21R, 21G, and 21B adjacent to each other are electrically separated from each other by an insulating film 24 and a pixel separation unit 26. In addition, although Figure 3 Although not shown in the figure, a peripheral circuit unit is formed in a peripheral area of ​​a pixel area formed in the substrate 12.

[0084] The photoelectric conversion units 21R, 21G, and 21B have the same configuration. Therefore, the configurations of the photoelectric conversion units 21R, 21G, and 21B will be described by taking the photoelectric conversion unit 21G as an example. Figure 3 , for constituent elements constituting the photoelectric conversion unit 21B, reference numerals are not shown.

[0085] like Figure 3As shown, the photoelectric conversion unit 21G has p-type semiconductor regions 212 and 213 formed on the front side and the back side of the substrate 12 and an n-type semiconductor region 211 formed between the p-type semiconductor region 212 and the p-type semiconductor region 213. In the photoelectric conversion unit 21G, the main part of the photodiode is formed by the pn junction between the p-type semiconductor regions 212 and 213 and the n-type semiconductor region 211. The photoelectric conversion unit 21G generates a signal charge corresponding to the amount of incident light, and stores the generated signal charge in the n-type semiconductor region 211. In addition, the electrons causing the dark current generated at the interface of the substrate 12 are absorbed by holes, which are a large number of carriers of the p-type semiconductor regions 212 and 213 formed on the front and back sides of the substrate 12. As a result, the dark current generated in the photoelectric conversion unit 21G is suppressed. Furthermore, the photoelectric conversion units 21R, 21G, and 21B are electrically separated from each other by the pixel separation sections 26 composed of the p-type semiconductor region covering the periphery of the n-type semiconductor region 211 and the insulating film 24 disposed between the pixel separation sections 26 .

[0086] like Figure 3 As shown, the green pixel 2G has a floating diffusion (hereinafter sometimes referred to as "FD") portion 30G (see Figure 2 ), the floating diffusion portion 30G is formed in the center portion between the four photoelectric conversion units 21Ga, 21Gb, 21Gc and 21Gd arranged in 2 rows and 2 columns. The FD portion 30G is composed of an n-type semiconductor region formed by ion-implanting n-type impurities at a high concentration into a p-well layer 29 formed on the front side of the substrate 12. When viewed from a direction orthogonal to the green filter 22G, the FD portion 30G is arranged overlapping with the intersection of the second light-shielding region 32 provided in the green pixel 2G. When viewed from a direction orthogonal to the green filter 22G, the FD portion 30G is arranged on the inner side of the intersection of the second light-shielding region 32. As a result, it is difficult for light entering from the on-chip lens 23G side to enter the FD portion 30G.

[0087] The blue pixel 2B has an FD portion 30B (see Figure 2 ), the FD portion 30B is formed in the center portion between the four photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd arranged in 2 rows and 2 columns. Similarly, the red pixel 2R has the FD portion 30R (see Figure 2 ), the FD portion 30R is formed in the center portion between the four photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd arranged in 2 rows and 2 columns. The FD portion 30R and the FD portion 30B have the same configuration as the FD portion 30G.

[0088] like Figure 2As shown, the pixel transistors include four types of transistors, namely, four transfer transistors, a reset transistor, an amplification transistor, and a selection transistor (a total of 7).

[0089] When viewed from a direction orthogonal to the green filter 22G, the transfer transistors GTr11, GTr12, GTr13, and GTr14 provided in the green pixel 2G are arranged in the center portion of the green pixel 2G. That is, when viewed from the above direction, the transfer transistors GTr11, GTr12, GTr13, and GTr14 are arranged in the corners where the photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd are adjacent to each other. The transfer transistor GTr11 is arranged in the green sub-pixel 20Ga, the transfer transistor GTr12 is arranged in the green sub-pixel 20Gb, the transfer transistor GTr13 is arranged in the green sub-pixel 20Gc, and the transfer transistor GTr14 is arranged in the green sub-pixel 20Gd. The transfer transistors GTr11, GTr12, GTr13, and GTr14 provided in the green pixel 2G have an FD portion 30G formed in the center portion between the photoelectric conversion units 21G, a gate electrode GE, and a gate insulating film 17 formed on the front side of the substrate 12 (see Figure 3 , the gate insulating film 17 of each of the transfer transistors GTr11 and GTr12 is not shown).

[0090] like Figure 2 As shown, among the pixel transistors of the green pixel 2G, the reset transistor GTr2, the amplifying transistor GTr3, and the selecting transistor GTr4 are shared by the four photoelectric conversion units 21G that share the FD portion 30G with each other. The reset transistor GTr2, the amplifying transistor GTr3, and the selecting transistor GTr4 of the green pixel 2G arranged to be sandwiched between the red pixels 2R in the direction in which the selection signal line 9b is arranged are arranged between one of the red pixels 2R on both sides and the green pixel 2G. In addition, the reset transistor GTr2, the amplifying transistor GTr3, and the selecting transistor GTr4 of the green pixel 2G arranged to be sandwiched between the blue pixels 2B in the direction in which the selection signal line 9b is arranged are arranged between one of the blue pixels 2B on both sides and the green pixel 2G. As a result, when viewed from a direction orthogonal to the green filter 22G, the reset transistor GTr2, the amplifying transistor GTr3, and the selecting transistor GTr4 of the green pixel 2G are arranged to overlap with the first light shielding area 31 on the opposite side of the light incident side.

[0091] The reset transistor GTr2 has a source region S, a drain region D, and a gate electrode GE formed between the source region S and the drain region D. The amplification transistor GTr3 has a source region S, a drain region D, and a gate electrode GE formed between the source region S and the drain region D. The selection transistor GTr4 has a source region S, a drain region D, and a gate electrode GE formed between the source region S and the drain region D.

[0092] Since the reset transistor GTr2, the amplifying transistor GTr3, and the selecting transistor GTr4 have the same cross-sectional structure as the transfer transistors GTr11, GTr12, GTr13, and GTr14, their cross-sectional structures are not shown. Similar to the FD portion 30G, the source region S and the drain region D of the reset transistor GTr2, the amplifying transistor GTr3, and the selecting transistor GTr4 are each formed by an n-type high-concentration impurity region in the p-well layer 29 formed on the front surface of the substrate 12. In addition, the gate electrode GE of each of the reset transistor GTr2, the amplifying transistor GTr3, and the selecting transistor GTr4 is formed on the front surface side of the substrate 12 via the gate insulating film 17.

[0093] In the green pixel 2G, the FD portion 30G is electrically connected to the source regions of the transfer transistors GTr11, GTr12, GTr13 and GTr14, the drain region D of the reset transistor GTr2 and the gate electrode GE of the amplifier transistor GTr3. In addition, the drain region D of the amplifier transistor GTr3 and the source region S of the selection transistor GTr4 are shared.

[0094] like Figure 2 As shown, the pixel transistors provided in the red pixel 2R include four types of transistors, namely, transfer transistors RTr11, RTr12, RTr13 and RTr14, reset transistor RTr2, amplification transistor RTr3 and selection transistor RTr4 (a total of 7 transistors). Similarly, the pixel transistors provided in the blue pixel 2B include four types of transistors, namely, transfer transistors BTr11, BTr12, BTr13 and BTr14, reset transistor BTr2, amplification transistor BTr3 and selection transistor BTr4 (a total of 7 transistors).

[0095] The reset transistor RTr2, the amplifying transistor RTr3, and the selecting transistor RTr4 provided in the red pixel 2R are provided to be shared by the four photoelectric conversion units 21R that share the FD portion 30R with each other. In the direction in which the selection signal line 9b is arranged, the reset transistor RTr2, the amplifying transistor RTr3, and the selecting transistor RTr4 are alternately arranged with the reset transistor GTr2, the amplifying transistor GTr3, and the selecting transistor GTr4 provided in the green pixel 2G. When viewed from a direction orthogonal to the red filter 22R, the reset transistor RTr2, the amplifying transistor RTr3, and the selecting transistor RTr4 are arranged to overlap with the first light shielding region 31 on the opposite side of the light incident side.

[0096] The reset transistor BTr2, the amplifying transistor BTr3, and the selecting transistor BTr4 provided in the blue pixel 2B are provided to be shared by the four photoelectric conversion units 21B that share the FD portion 30B with each other. In the direction in which the selection signal line 9b is arranged, the reset transistor BTr2, the amplifying transistor BTr3, and the selecting transistor BTr4 are alternately arranged with the reset transistor GTTr2, the amplifying transistor GTTr3, and the selecting transistor GTTr4 provided in the green pixel 2G. When viewed from a direction orthogonal to the blue filter 22B, the reset transistor BTr2, the amplifying transistor BTr3, and the selecting transistor BTr4 are arranged to overlap with the first light shielding region 31 on the opposite side of the light incident side.

[0097] Transfer transistors RTr11, RTr12, RTr13 and RTr14, transfer transistors BTr11, BTr12, BTr13 and BTr14 have the same configuration as transfer transistors GTTr11, GTTr12, GTTr13 and GTTr14, and exhibit the same functions as transfer transistors GTTr11, GTTr12, GTTr13 and GTTr14. Reset transistor RTr2 and reset transistor BTr2 have the same configuration as reset transistor GTTr2, and exhibit the same functions as reset transistor GTTr2. Amplification transistor RTr3 and amplification transistor BTr3 have the same configuration as amplification transistor GTTr3, and exhibit the same functions as amplification transistor GTTr3. Selection transistor RTr4 and selection transistor BTr4 have the same configuration as selection transistor GTTr4, and exhibit the same functions as selection transistor GTTr4. Therefore, a detailed description of the respective structures of the transfer transistors RTr11, RTr12, RTr13 and RTr14, the reset transistor RTr2, the amplification transistor RTr3, the selection transistor RTr4, the transfer transistors BTr11, BTr12, BTr13 and BTr14, the reset transistor BTr2, the amplification transistor BTr3 and the selection transistor BTr4 is omitted.

[0098] Back to Figure 3The insulating film 24 is embedded between the pixel separation portions 26 and is formed on the entire surface of the back side of the substrate 12. As a forming material of the insulating film 24, for example, silicon oxide, silicon nitride, silicon nitride oxide, or resin can be used. In addition, as a forming material of the insulating film 24, a material having a characteristic of not having a positive fixed charge or a characteristic of having a small amount of positive fixed charge can be used.

[0099] When the insulating film 24 is embedded between the pixel separation sections 26, the photoelectric conversion units provided in the adjacent pixels 2 are separated from each other by the insulating film 24. As a result, the signal charge is less likely to leak to the adjacent pixels, so when the signal charge exceeding the saturation charge amount (Qs) is generated, the leakage of the overflowing signal charge to the adjacent photoelectric conversion unit can be reduced. Therefore, the insulating film 24 can suppress electronic color mixing.

[0100] The planarization film 25 is formed on the entire surface of the insulating film 24 including the first light shielding region 31 and the second light shielding region 32. As a result, the planarization film 25 can planarize the surface on the back side of the substrate 12. As a formation material of the planarization film 25, for example, an organic material such as resin can be used.

[0101] Red filter 22R (in Figure 3 The green filter 22G and the blue filter 22B are formed in contact with the back side of the planarization film 25 which is the light incident side. Figure 3 The surfaces of the light incident surface side (i.e., the side not in contact with the planarization film 25) of the green filter 22G and the blue filter 22B have a flat shape following the planarization film 25. The red filter 22R is a constituent element that transmits light having a wavelength corresponding to red and absorbs light having the remaining wavelengths. The green filter 22G is a constituent element that transmits light having a wavelength corresponding to green and absorbs light having the remaining wavelengths. The blue filter 22B is a constituent element that transmits light having a wavelength corresponding to blue and absorbs light having the remaining wavelengths.

[0102] The red filter 22R is not separated from each of the four red sub-pixels 20Ra, 20Rb, 20Rc, and 20Rd, but is formed continuously. As a result, the red filter 22R is shared by the four photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd. The light transmitted through the red filter 22R enters any one of the photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd provided in the red sub-pixels 20Ra, 20Rb, 20Rc, and 20Rd. The green filter 22G is not separated from each of the four green sub-pixels 20Ga, 20Gb, 20Gc, and 20Gd, but is formed continuously. As a result, the green filter 22G is shared by the four photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd. Light passing through the green filter 22G enters any one of the photoelectric conversion units 21G provided in the green sub-pixels 20Ga, 20Gb, 20Gc, and 20Gd. The blue filter 22B is not separated by each of the four blue sub-pixels 20Ba, 20Bb, 20Bc, and 20Bd, but is formed continuously. As a result, the blue filter 22B is shared by the four photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd. Light passing through the blue filter 22B enters any one of the photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd provided in the blue sub-pixels 20Ba, 20Bb, 20Bc, and 20Bd.

[0103] The on-chip lens 23R is formed on the light incident surface side of the red filter 22R, the on-chip lens 23G is formed on the light incident surface side of the green filter 22G, and the on-chip lens 23B is formed on the light incident surface side of the blue filter 22B. The on-chip lens 23R is formed for each of the red sub-pixels 20Ra, 20Rb, 20Rc, and 20Rd, the on-chip lens 23G is formed for each of the green sub-pixels 20Ga, 20Gb, 20Gc, and 20Gd, and the on-chip lens 23B is formed for each of the blue sub-pixels 20Ba, 20Bb, 20Bc, and 20Bd. Therefore, one red pixel 2R has four on-chip lenses 23R, one green pixel 2G has four on-chip lenses 23G, and one blue pixel 2B has four on-chip lenses 23B. The on-chip lenses 23R, 23G, and 23B can collect light entering from the outside and allow the collected light to efficiently enter the photoelectric conversion units 21R, 21G, 21B via the red filter 22R, the green filter 22G, and the blue filter 22B.

[0104] The wiring layer 13 is formed on the front side of the substrate 12, and has wirings 15 stacked in multiple layers (three layers in the present embodiment) via an interlayer insulating film 14. The reset signal and the selection signal output from the vertical drive circuit 4 are input to the reset transistor and the selection transistor among the pixel transistors provided in the pixel 2 via the wiring 15 formed in the wiring layer 13. In addition, the power supply for driving the pixel transistor is also input via the wiring 15 formed in the wiring layer 13. As a result, the pixel transistor is driven.

[0105] The support substrate 11 is formed on the surface of the wiring layer 13 opposite to the side facing the substrate 12. The support substrate 11 is used to ensure the strength of the substrate 12 in the manufacturing stage. The support substrate 11 is made of, for example, a silicon substrate.

[0106] In the solid-state imaging device 1a having the above-described configuration, light is irradiated from the back side of the substrate 12, and the light transmitted through the on-chip lenses 23R, 23G, and 23B, the red filter 22R, the green filter 22G, and the blue filter 22B is photoelectrically converted by the photoelectric conversion units 21R, 21G, and 21B to generate signal charges. The signal charges generated by the photoelectric conversion units 21R, 21G, and 21B are output as pixel signals from the vertical signal lines 9a formed by the desired wirings 15 of the wiring layer 13 via the pixel transistors formed on the front side of the substrate 12.

[0107] Next, we will refer to Figure 4 The effects of the solid-state imaging device 1a according to this embodiment will be described. Figure 4 In order to facilitate understanding, when the second light shielding area 32 overlaps with the first light shielding area 31, the first light shielding area 31 is shaded in the area where the first light shielding area 31 and the second light shielding area 32 overlap with each other, and the first light shielding area 31 is not shaded in the area where the first light shielding area 31 and the second light shielding area 32 do not overlap with each other. In addition, light entering the solid-state imaging device 1a is refracted at the interface where different constituent elements contact each other, but Figure 4 In the figure, for ease of understanding, the refraction of light is not shown.

[0108] For example, in the case where the first light shielding region 31 has the same width as the second light shielding region 32, as shown in FIG. Figure 4As shown by the dotted arrow in the middle, part of the light L1 that passes through the green filter 22G and is guided to the first light shielding area 31 is reflected by the first light shielding area 31, and the rest of the light L1 enters the blue sub-pixel 20B arranged next to the green sub-pixel 20G having the green filter 22G. The photoelectric conversion unit 21B provided in the blue sub-pixel 20B is an element for photoelectrically converting light corresponding to a blue wavelength, but the light corresponding to a green wavelength that passes through the green filter 22G also enters the photoelectric conversion unit 21B. Therefore, color mixing occurs in the blue sub-pixel 20B, and the image quality of the solid-state imaging device 1a deteriorates.

[0109] On the other hand, in the solid-state image pickup device 1a according to the present embodiment, as shown in FIG. Figure 4 As shown, light L1 emitted from the outside to the solid-state imaging device 1a passes through the on-chip lens 23G and the green filter 22G, and is incident on the first light-shielding area 31. The light L1 incident on the first light-shielding area 31 is reflected by the first light-shielding area 31, and is absorbed by the blue filter 22B adjacent to the green filter 22G. As described above, the first light-shielding area 31 reflects the incident light L1 that passes through the green filter 22G, so that light corresponding to the green wavelength can be prevented from entering the blue sub-pixel 20B arranged next to the green sub-pixel 20G having the green filter 22G. As a result, the solid-state imaging device 1a can prevent color mixing, and can suppress the degradation of image quality.

[0110] The second light shielding region 32 has a narrower width than the first light shielding region 31. Figure 4 As shown, for example, a portion of the light L1 that passes through the blue filter 22B and is directed to the second light shielding region 32 is more likely to enter the adjacent sub-pixel (the blue sub-pixel 20B in this example) than the light L1 directed to the first light shielding region 31. However, since the sub-pixel of the same color (the blue sub-pixel 20B in this example) is arranged on the opposite side of the light incident surface side of the second light shielding region 32, color mixing does not occur.

[0111] The solid-state imaging device 1a can improve sensitivity while preventing color mixing by making the width of the second light shielding region 32 narrower than the width of the first light shielding region 31. In addition, the second light shielding region 32 is arranged to overlap with the FD portions 30R, 30G, and 30B.

[0112] Incidentally, in the period until the reset transistor switches from the on state to the off state and then the transfer transistor becomes the on state, the electrons that undergo photoelectric conversion near the FD sections 30R, 30G, and 30B and enter the FD sections 30R, 30G, and 30B are detected as false signals. In particular, a back-illuminated device designed to detect long-wavelength light such as infrared light may have a light-shielding region between sub-pixels of the same color to suppress false signals. The solid-state imaging device 1a according to the present embodiment can improve sensitivity while suppressing the photoelectric conversion that occurs near the FD sections 30R, 30G, and 30B during this period by making the width of the second light-shielding region 32 narrower than the width of the first light-shielding region 31.

[0113] As described above, the solid-state imaging device 1a according to the present embodiment has a green pixel 2G having a plurality of on-chip lenses 23G and a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd that share a green filter 22G with each other. In addition, the solid-state imaging device 1a has a blue pixel 2B that is arranged adjacent to the green pixel 2G and has a plurality of on-chip lenses 23B and a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd that share a blue filter 22B with each other. In addition, the solid-state imaging device 1a has a red pixel 2R that is arranged adjacent to the green pixel 2G and has a plurality of on-chip lenses 23R and a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd that share a red filter 22R with each other. In addition, the solid-state imaging device 1a has a first light shielding region 31 that is provided between the green pixel 2G and each of the blue pixel 2B and the red pixel 2R.

[0114] In the solid-state image pickup device 1 a having the above-described configuration, color mixing between pixels 2 having different colors can be prevented by the first light shielding region 31 , and thus degradation of image quality can be suppressed.

[0115] In addition, the green pixel 2G has a second light shielding region 32 provided between the green sub-pixel 20Ga and the photoelectric conversion unit 21Gb, between the green sub-pixel 20Ga and the photoelectric conversion unit 21Gc, between the green sub-pixel 20Gd and the photoelectric conversion unit 21Gb, and between the green sub-pixel 20Gd and the photoelectric conversion unit 21Gc. The blue pixel 2B has a second light shielding region 32 provided between the blue sub-pixel 20Ba and the photoelectric conversion unit 21Bb, between the blue sub-pixel 20Ba and the photoelectric conversion unit 21Bc, between the blue sub-pixel 20Bd and the photoelectric conversion unit 21Bb, and between the blue sub-pixel 20Bd and the photoelectric conversion unit 21Bc. The red pixel 2R has a second light shielding region 32 provided between the red sub-pixel 20Ra and the photoelectric conversion unit 21Rb, between the red sub-pixel 20Ra and the photoelectric conversion unit 21Rc, between the red sub-pixel 20Rd and the photoelectric conversion unit 21Rb, and between the red sub-pixel 20Rd and the photoelectric conversion unit 21Rc. The width of the second light shielding region 32 is narrower than the width of the first light shielding region 31 .

[0116] In the solid-state imaging device 1a having the above-described structure, during the period until the reset transistor switches from the on state to the off state and then the transfer transistor becomes the on state, electrons generated by photoelectric conversion near the FD portions 30R, 30G and 30B can be prevented from being detected as false signals in the FD portions 30R, 30G and 30B, and the sensitivity can be improved.

[0117] [Second embodiment]

[0118] Will refer to Figure 5 A solid-state imaging device according to a second embodiment of the present disclosure is described. The solid-state imaging device 1b according to the present embodiment is characterized in that the green pixel 2G does not have a second light shielding area. In the description of the present embodiment, constituent elements having the same operation and function as the solid-state imaging device 1a according to the first embodiment are represented by the same reference numerals, and their description will be omitted.

[0119] Since the solid-state image pickup device according to the present embodiment has the same overall configuration as that of the solid-state image pickup device 1 a according to the first embodiment, a description thereof will be omitted.

[0120] like Figure 5As shown, a blue pixel (an example of a first pixel) 2B provided in a solid-state imaging device 1b has: a blue sub-pixel 20Ba (an example of a first sub-pixel) having a photoelectric conversion unit 21Ba (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd; a blue sub-pixel 20Bd (an example of a first sub-pixel) having a photoelectric conversion unit 21Bd (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd; a blue sub-pixel 20Bb (an example of a second sub-pixel) having a photoelectric conversion unit 21Bb (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd; and a blue sub-pixel 20Bc (an example of a second sub-pixel) having a photoelectric conversion unit 21Bc (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd. The blue pixel 2B has a second light shielding region 32 between the blue sub-pixel 20Ba and the blue sub-pixel 20Bd and between the blue sub-pixel 20Bb and the blue sub-pixel 20Bc.

[0121] Similarly, a red pixel (an example of a first pixel) 2R provided in the solid-state imaging device 1b has: a red sub-pixel 20Ra (an example of a first sub-pixel) having a photoelectric conversion unit 21Ra (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd; a red sub-pixel 20Rd (an example of a first sub-pixel) having a photoelectric conversion unit 21Rd (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd; a red sub-pixel 20Rb (an example of a second sub-pixel) having a photoelectric conversion unit 21Rb (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd; and a red sub-pixel 20Rc (an example of a second sub-pixel) having a photoelectric conversion unit 21Rc (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd. The red pixel 2R has a second light shielding region 32 between the red sub-pixel 20Ra and the red sub-pixel 20Rd and between the red sub-pixel 20Rb and the red sub-pixel 20Rc.

[0122] On the other hand, the green pixel (an example of a second pixel) 2G provided in the solid-state imaging device 1b has: a green sub-pixel 20Ga (an example of a first sub-pixel) having a photoelectric conversion unit 21Ga (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd; a green sub-pixel 20Gd (an example of a first sub-pixel) having a photoelectric conversion unit 21Gd (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd; a green sub-pixel 20Gb (an example of a second sub-pixel) having a photoelectric conversion unit 21Gb (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd; and a green sub-pixel 20Gc (an example of a second sub-pixel) having a photoelectric conversion unit 21Gc (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd. The green pixel 2G does not have a light shielding region between the green sub-pixel 20Ga and the green sub-pixel 20Gd and between the green sub-pixel 20Gb and the green sub-pixel 20Gc.

[0123] The red filter 22R (an example of a first color filter) of the red pixel 2R and the blue filter 22B (an example of a first color filter) of the blue pixel 2B have lower visual sensitivity than the green filter 22G (an example of a second color filter) of the green pixel 2G. Therefore, in the case where the first color filter (corresponding to the red filter 22R and the blue filter 22B in the present embodiment) has lower visual sensitivity than the second color filter (corresponding to the green filter 22G in the present embodiment), the second light shielding area 32 is provided in the first pixel (corresponding to the red pixel 2R and the blue pixel 2B in the present embodiment).

[0124] As described above, since a light shielding area is not provided in the green pixel 2G having the green filter 22G having the highest visual sensitivity among the red filter 22R, the green filter 22G, and the blue filter 22B, the amount of light reflected by the green pixel 2G is reduced. As a result, the solid-state imaging device 1b is able to improve sensitivity. On the other hand, in the solid-state imaging device 1b, since the second light shielding area 32 is not provided in the green pixel 2G, the possibility of detecting a false signal based on the photoelectric conversion near the FD portion 30G in the green pixel 2G is high compared to the solid-state imaging device 1a according to the first embodiment. However, the shorter the wavelength of light entering the solid-state imaging device 1b, the more difficult it is for the light to reach the vicinity of the FD portion, so it is difficult to detect a false signal in the green pixel 2G, and there is almost no problem.

[0125] As described above, the solid-state imaging device 1b according to the present embodiment includes a red pixel 2R having a red filter 22R and a photoelectric conversion unit 21R, a green pixel 2G having a green filter 22G and a photoelectric conversion unit 21G, a blue pixel 2B having a blue filter 22B and a photoelectric conversion unit 21B, and a first light shielding area 31 arranged between the green pixel 2G and the blue pixel 2B, and between the green pixel 2G and the red pixel 2R.

[0126] In the solid-state image pickup device 1 b having the above-described configuration, color mixing between pixels 2 having different colors can be prevented by the first light shielding region 31 , and thus degradation of image quality can be suppressed.

[0127] In addition, in the solid-state imaging device 1b, the second light shielding area 32 is provided in the red pixel 2R and the blue pixel 2B including the color filter of the color with lower visual sensitivity among the red pixel 2R, the green pixel 2G and the blue pixel 2B. In other words, the second light shielding area is not provided in the green pixel 2G including the green filter 22G with higher visual sensitivity. As a result, in the solid-state imaging device 1b, the amount of light reflected by the green pixel 2G including the green filter 22G with the highest visual sensitivity among the red filter 22R, the green filter 22G and the blue filter 22B can be reduced, so the sensitivity can be improved.

[0128] [Third embodiment]

[0129] Will refer to Figure 6 A solid-state imaging device according to a third embodiment of the present disclosure is described. The solid-state imaging device 1c according to the present embodiment is characterized in that the green pixel 2G and the blue pixel 2B do not have a second light shielding area. In the description of the present embodiment, constituent elements having the same operation and function as the solid-state imaging device 1a according to the first embodiment are represented by the same reference numerals, and their description will be omitted.

[0130] Since the solid-state image pickup device according to the present embodiment has the same overall configuration as that of the solid-state image pickup device 1 a according to the first embodiment, a description thereof will be omitted.

[0131] like Figure 6As shown, a red pixel (an example of a first pixel) 2R provided in a solid-state imaging device 1c has: a red sub-pixel 20Ra (an example of a first sub-pixel) having a photoelectric conversion unit 21Ra (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd; a red sub-pixel 20Rd (an example of a first sub-pixel) having a photoelectric conversion unit 21Rd (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd; a red sub-pixel 20Rb (an example of a second sub-pixel) having a photoelectric conversion unit 21Rb (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd; and a red sub-pixel 20Rc (an example of a second sub-pixel) having a photoelectric conversion unit 21Rc (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd. The red pixel 2R has a second light shielding region 32 between the red sub-pixel 20Ra and the red sub-pixel 20Rd and between the red sub-pixel 20Rb and the red sub-pixel 20Rc.

[0132] On the other hand, the green pixel (an example of a second pixel) 2G provided in the solid-state imaging device 1c has: a green sub-pixel 20Ga (an example of a first sub-pixel) having a photoelectric conversion unit 21Ga (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd; a green sub-pixel 20Gd (an example of a first sub-pixel) having a photoelectric conversion unit 21Gd (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd; a green sub-pixel 20Gb (an example of a second sub-pixel) having a photoelectric conversion unit 21Gb (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd; and a green sub-pixel 20Gc (an example of a second sub-pixel) having a photoelectric conversion unit 21Gc (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd. The green pixel 2G does not have a light shielding region between the green sub-pixel 20Ga and the green sub-pixel 20Gd and between the green sub-pixel 20Gb and the green sub-pixel 20Gc.

[0133] Similarly, a blue pixel (an example of a second pixel) 2B provided in the solid-state imaging device 1c has: a blue sub-pixel 20Ba (an example of a first sub-pixel) having a photoelectric conversion unit 21Ba (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd; a blue sub-pixel 20Bd (an example of a first sub-pixel) having a photoelectric conversion unit 21Bd (an example of a first photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd; a blue sub-pixel 20Bb (an example of a second sub-pixel) having a photoelectric conversion unit 21Bb (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd; and a blue sub-pixel 20Bc (an example of a second sub-pixel) having a photoelectric conversion unit 21Bc (an example of a second photoelectric conversion unit) among a plurality of photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd. The blue pixel 2B does not have a light shielding region between the blue sub-pixel 20Ba and the blue sub-pixel 20Bd and between the blue sub-pixel 20Bb and the blue sub-pixel 20Bc.

[0134] Therefore, the red filter 22R (an example of a first color filter) of the red pixel 2R is a color filter having a color with a longer wavelength than the green filter 22G (an example of a second color filter) of the green pixel 2G and the blue filter 22B (an example of a second color filter) of the blue pixel 2B. Therefore, in the case where the first color filter (corresponding to the red filter 22R in the present embodiment) is a color filter having a color with a longer wavelength than the second color filter (corresponding to the green filter 22G and the blue filter 22B in the present embodiment), the second light shielding area 32 is provided in the first pixel (corresponding to the red pixel 2R in the present embodiment).

[0135] As described above, no light shielding area is provided in the green pixel 2G and the blue pixel 2B other than the red pixel 2R including the red filter 22R having a color with a longer wavelength among the red filter 22R, the green filter 22G, and the blue filter 22B, so the amount of light reflected by the green pixel 2G and the blue pixel 2B is reduced. As a result, the solid-state imaging device 1c can improve sensitivity. In addition, compared with the solid-state imaging device 1a according to the first embodiment and the solid-state imaging device 1b according to the second embodiment, the solid-state imaging device 1c can improve sensitivity.

[0136] On the other hand, in the solid-state imaging device 1c, since the light shielding region is not provided in the green pixel 2G and the blue pixel 2B, the possibility of detecting a false signal based on the photoelectric conversion near the FD section 30G and 30B in the green pixel 2G and the blue pixel 2B is high compared with the solid-state imaging device 1a according to the first embodiment and the solid-state imaging device 1b according to the second embodiment. However, the shorter the wavelength of the light entering the solid-state imaging device 1c, the more difficult it is for the light to reach the vicinity of the FD section. Since the solid-state imaging device 1c has the second light shielding region 32 in the red pixel 2R including the red filter 22R of the color having the longest wavelength, it is possible to prevent the false signal from being detected in the red pixel 2R. In addition, in the green pixel 2G and the blue pixel 2B, the light shielding region is not provided, but compared with the red pixel 2R, the light entering the solid-state imaging device 1c does not reach the vicinity of the FD section 30G and 30B, and it is difficult to detect a false signal, so there is almost no problem.

[0137] As described above, the solid-state imaging device 1c according to the present embodiment includes a red pixel 2R having a red filter 22R and a photoelectric conversion unit 21R, a green pixel 2G having a green filter 22G and a photoelectric conversion unit 21G, a blue pixel 2B having a blue filter 22B and a photoelectric conversion unit 21B, and a first light-shielding area 31 arranged between the green pixel 2G and the blue pixel 2B, and between the green pixel 2G and the red pixel 2R.

[0138] In the solid-state image pickup device 1 c having the above-described configuration, color mixing between pixels 2 having different colors can be prevented by the first light shielding region 31 , and thus degradation of image quality can be suppressed.

[0139] Furthermore, in the solid-state imaging device 1c, the second light shielding region 32 is provided in the red pixel 2R having the red filter 22R (which is a color filter including a color having the longest wavelength) among the first pixel (the red pixel 2R in the present embodiment) and the second pixel (the green pixel 2G and the blue pixel 2B in the present embodiment), and is not provided in the remaining green pixels 2G and the blue pixels 2B. As a result, in the solid-state imaging device 1c, it is possible to prevent a false signal based on photoelectric conversion near the FD portion 30R from being detected in the red pixel 2R, and it is possible to reduce the amount of light reflected by the green pixel 2G and the blue pixel 2B, so that the sensitivity can be improved.

[0140] [Fourth embodiment]

[0141] Will refer to Figures 7 to 15A solid-state imaging device according to a fourth embodiment of the present disclosure is described. The solid-state imaging device 1d according to the present embodiment is characterized in that none of the red pixel 2R, the green pixel 2G, and the blue pixel 2B has a light shielding region. In the description of the present embodiment, constituent elements having the same operation and function as the solid-state imaging device 1a according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

[0142] Since the solid-state image pickup device 1d according to the present embodiment has the same overall configuration as that of the solid-state image pickup device 1a according to the first embodiment, a description thereof will be omitted.

[0143] like Figure 7 As shown, in the solid-state image pickup device 1d according to the present embodiment, none of the red pixel 2R, the green pixel 2G, and the blue pixel 2B has a light shielding region.

[0144] As a result, in the solid-state imaging device 1d, light is not reflected in the inner area of ​​each of the red pixel 2R, the green pixel 2G, and the blue pixel 2B (i.e., the area surrounded by the first light shielding area 31), so the amount of light entering the photoelectric conversion units 21R, 21G, and 21B increases compared to the solid-state imaging devices 1a, 1b, and 1c according to the first to third embodiments. As a result, the solid-state imaging device 1d can improve sensitivity compared to the solid-state imaging devices 1a, 1b, and 1c according to the first to third embodiments.

[0145] On the other hand, in the solid-state image pickup device 1d, since the FD portions 30R, 30G, and 30B are not shielded from light in the shielding area, a false signal based on photoelectric conversion near the FD portions 30R, 30G, and 30B is easily detected compared to the solid-state image pickup devices 1a, 1b, and 1c according to the first to third embodiments. However, in the case where the solid-state image pickup device 1d is a sensor that detects infrared rays or has a high-speed analog-to-digital conversion specification, detection of a false signal is hardly a problem.

[0146] Next, we will refer to Figure 8 The width of the first light shielding region provided in the solid-state imaging device 1d according to the present embodiment is described. The width of the first light shielding region in the present embodiment can be applied to the width of the first light shielding region provided in the solid-state imaging devices according to the first to third embodiments and the fifth to eighth embodiments to be described later.

[0147] Figure 8 The cross sections of the green pixel 2G and the blue pixel 2B are schematically shown.

[0148] like Figure 8As shown, the width of the first light shielding area 31 is defined as w. In addition, the spacing between the multiple on-chip lenses 23G in the green pixel (an example of the first pixel) 2G is defined as p1. In addition, the height from the virtual plane VP including the bottom surface 311 of the first light shielding area 31 to the top of the on-chip lens 23G closest to the first light shielding area 31 is defined as h1. In addition, when the length of light entering the photoelectric conversion unit 21G is defined as d1, the first light shielding area 31 satisfies the following expression (1). Here, the length d1 of light entry is the distance between the intersection of the virtual line VL1 of the vertex on the green pixel 2G side passing through the top and bottom surface 311 and the boundary DL of the green pixel 2G and the blue pixel (an example of the second pixel) 2B and the midpoint of the bottom surface 311 in the cross section orthogonal to the extension direction of the first light shielding area 31 including the top of the on-chip lens 23G closest to the first light shielding area 31. The length d1 of the entry is a length that causes color mixing when the first light shielding region 31 does not exist but does not cause color mixing when the first light shielding region 31 exists, and is, for example, 0.6 μm.

[0149] w>2×((p1 / 2)×d1 / (h1+d1))…(1)

[0150] In addition, the width of the first light shielding area 31 based on the shape of the red pixel 2R and the blue pixel 2B (both are examples of the second pixel) can be defined as the same as the width of the first light shielding area 31 based on the shape of the green pixel 2G. Here, the width of the first light shielding area 31 based on the shape of the red pixel 2R and the blue pixel 2B will be described by taking the blue pixel 2B as an example.

[0151] like Figure 8 As shown, the width of the first light shielding area 31 is defined as w. In addition, the spacing between the multiple on-chip lenses 23B in the blue pixel 2B is defined as p2. In addition, the height from the virtual plane VP including the bottom surface 311 of the first light shielding area 31 to the top of the on-chip lens 23B closest to the first light shielding area 31 is defined as h2. When the length of light entering the photoelectric conversion unit 21B is defined as d2, the first light shielding area 31 satisfies the following expression (2). The length d2 of light entry is the distance between the intersection of the virtual line VL2 of the vertex on the blue pixel 2B side passing through the top and bottom surface 311 and the boundary DL of the green pixel 2G and the blue pixel (an example of the second pixel) 2B in a cross section orthogonal to the extension direction of the first light shielding area 31, and the midpoint of the bottom surface 311. The length d2 of the entry is a length that causes color mixing when the first light shielding region 31 does not exist but does not cause color mixing when the first light shielding region 31 exists, and is, for example, 0.6 μm.

[0152] w>2×((p2 / 2)×d2 / (h2+d2))…(2)

[0153] The red pixel 2R, the green pixel 2G, and the blue pixel 2B provided in the solid-state imaging device 1d are formed in the same shape. Therefore, the width of the first light shielding region 31 obtained using expression (1) and the width of the first light shielding region 31 obtained using expression (2) are the same. Therefore, the first light shielding region 31 provided in the solid-state imaging device 1d has approximately the same width in the pixel region 3.

[0154] Fig. 9 : is a graph showing the relationship between the line width of the optical black (OPB) for defining the black level (ie, the width of the first light shielding region) and the color mixing resistance of the pixel. Fig. 9 The horizontal axis of the graph in represents the incident angle [°] of light entering the on-chip lens. A positive incident angle represents incident from an angle corrected by pupils, and a negative incident angle represents incident from an angle opposite to that corrected by pupils. Fig. 9 “B / G@G light [%]” on the vertical axis of the graph in represents the ratio of green light entering the green pixel leaking into the blue pixel. Fig. 9 The curve C1 connecting the square marks shown is the color mixing resistance of the pixel of the solid-state imaging device, and shows the result of wave simulation in the case where the line width of the optical black is 360 nm. Fig. 9 The curve C2 connecting diamond marks shown is the color mixing resistance of the pixels of the solid-state imaging device, and shows the result of wave simulation in the case where the line width of the optical black is 560 nm. Fig. 9 A curve C3 connecting triangular marks shown is the color mixing resistance of the pixels of the solid-state imaging device, and shows the result of wave simulation in the case where the line width of the optical black is 720 nm.

[0155] like Fig. 9 As shown in FIG. 1 , by increasing the line width of the optical black, the color mixing resistance of the pixel is improved. Therefore, by increasing the width of the first light shielding area 31, the color mixing resistance of the pixel of the solid-state imaging device 1d is improved. However, when the width of the first light shielding area 31 is increased, the amount of light reflected by the first light shielding area 31 in the light entering the solid-state imaging device 1d increases, so there is a problem that the sensitivity of the solid-state imaging device 1d is reduced.

[0156] Table 1 shows the sensitivity and color mixing resistance related to the line width and structure of the optical black. The "OPB line width" in Table 1 indicates the line width of the optical black on the light incident side. The "OPB structure" indicates the shape of the optical black (i.e., the light shielding area) when a pixel is observed from a direction orthogonal to the color filter. The "Sensitivity @ Center 0°" in Table 1 indicates the sensitivity when light enters the central pixel in the pixel area of ​​the solid-state imaging device at an incident angle of 0°. The "Color Mixing @ H End -30°" in Table 1 indicates the color mixing resistance of the pixels arranged in the end portion in the longitudinal direction of the pixel area to incident light at a reverse angle of 30° from pupil correction. The "Grid-like" in the "OPB Structure" column indicates a shape consisting of a frame shape surrounding the pixel and a cross shape extending between opposite sides of the light shielding area. That is, the "Grid-like" indicates a shape consisting of a frame shape surrounding the pixel and a cross shape extending between opposite sides of the light shielding area. Figure 2 The shape shown is formed by the first light shielding area and the second light shielding area (here, the widths of the two light shielding areas are the same). The "frame shape" in the "OPB structure" column indicates a frame shape surrounding a pixel.

[0157] [Table 1]

[0158]

[0159] As shown in Table 1, when the "OPB line width" is 360nm, the sensitivity in "Sensitivity @ Center 0°" is defined as a reference value of 100%. In addition, in this case, the pixel's resistance to color mixing is 40%. When the "OPB line width" is 560nm, the sensitivity in "Sensitivity @ Center 0°" is 90% when the "OPB structure" is a grid shape, and is 95% when the "OPB structure" is a frame shape. In addition, in this case, regardless of the OPB structure, the pixel's resistance to color mixing is 33%. When the "OPB line width" is 720nm, the sensitivity in "Sensitivity @ Center 0°" is 80% when the "OPB structure" is a grid shape, and is 90% when the "OPB structure" is a frame shape. In addition, in this case, regardless of the OPB structure, the pixel's resistance to color mixing is 29%.

[0160] As described above, when the line width of OPB is increased, the sensitivity decreases and the resistance to color mixing increases. In addition, for the OPB structures in a lattice shape and a frame shape, the resistance to color mixing has the same value. Therefore, from the point of view of suppressing color mixing, there will be no problem even if the solid-state imaging device does not have a second shading area. For example, when the pitch p1 (pitch p2) of the on-chip lens is 2.2 μm, the height h1 (height h2) from the virtual plane VP including the bottom surface 311 of the first shading area 31 to the top of the on-chip lens 23G (on-chip lens 23B) is 2.2 μm, and the entry length d1 (entry length d2) is 0.6 μm, the right sides of expressions (1) and (2) are 0.47 μm, respectively. The width of the first shading area in the case where the "OPB line width" shown in Table 1 is 560 nm and the width of the first shading area in the case where the "OPB line width" is 720 nm are both longer than 0.47 μm and satisfy expressions (1) and (2). Therefore, in the solid-state imaging device 1 d , the width of the first light shielding region 31 can be changed depending on whether priority is given to sensitivity or to color mixture resistance.

[0161] Fig.10 and Fig.12 It is a graph in which the measured results of the oblique incidence characteristics of the central portion of the pixel region of the solid-state imaging device are represented by the image height. Fig.11 and Fig.13 : is a graph in which the measured results of the oblique incidence characteristics of the end portion in the longitudinal direction of the pixel region of the solid-state imaging device are represented by the image height. Figures 10 to 13 The horizontal axis of the graph in represents the incident direction [°] of light entering the on-chip lens. A positive value of the incident direction indicates that the light is incident from one side (e.g., the right side) relative to the center of the pixel area in the longitudinal direction of the pixel area, and a negative value of the incident direction indicates that the light is incident from the other side (e.g., the left side). Fig.10 and Fig.11 “G output [mV]” shown on the vertical axis of the graph in represents an output voltage of green light obtained when white light enters the pixel. Fig.12 and Fig.13 “G output (normalized)” shown on the vertical axis of the graph in represents the output of green light obtained when white light enters the pixel and normalized to the value of 0° in the incident direction. Figures 10 to 13 The curves Coc1 and Coe1 shown represent oblique incidence characteristics in the case where the structure of the optical black is frame-shaped and its line width is 600 nm. Figures 10 to 13 The curves Coc2 and Coe2 shown represent the oblique incidence characteristics when the structure of the optical black is a grid shape and its line width is 400nm. The frame shape has the same structure as the "frame shape" shown in the "OPB structure" column in Table 1, and the grid shape has the same structure as the "grid shape" shown in the "OPB structure" column in Table 1.

[0162] like Fig.10 and Fig.11 As shown, the oblique incidence characteristics of the solid-state imaging device are such that the output of green light when the optical black structure is a frame shape is higher than the output of green light when the optical black structure is a grid shape in the center and end of the pixel area. Fig.12 As shown in FIG. 1 , when the output of green light is normalized with the value of 0° in the incident direction, the oblique incidence characteristics of the central portion of the pixel region of the solid-state imaging device are as follows: within the range of ±30° in the incident direction, the output of green light when the structure of the optical black is a grid is almost the same as the output of green light when the structure of the optical black is a frame, and within the range of -60° to -30° and +30° to +60° in the range of incident angles, the output of green light when the structure of the optical black is a frame is higher than the output of green light when the structure of the optical black is a grid. Fig.13 As shown, when the output of green light is normalized with the value of 0° in the incident direction, the oblique incidence characteristics of the end portion in the longitudinal direction of the pixel area of ​​the solid-state imaging device are as follows: in the range of -10° to +60° in the incident direction, the output of green light when the structure of the optical black is a grid shape is almost the same as the output of green light when the structure of the optical black is a frame shape, and in the range of -60° to -10° in the incident angle, the output of green light when the structure of the optical black is a frame shape is higher than the output of green light when the structure of the optical black is a grid shape.

[0163] Fig.14 This is a graph showing the measured results of line crawl R (LCR) in the center of the pixel region of the solid-state imaging device represented by the image height. LCR represents a step between green pixels and blue pixels caused by color mixing when red light is irradiated. Fig.15 : is a graph in which the actual measurement result of the LCR of the end part in the longitudinal direction of the pixel area of ​​the solid-state imaging device is represented by the image height. Fig.14 and Fig.15 The horizontal axis of the graph in represents the incident direction [°] of light entering the on-chip lens. A positive value of the incident direction indicates that the light is incident from one side (e.g., the right side) relative to the center of the pixel area in the longitudinal direction of the pixel area, and a negative value of the incident direction indicates that the light is incident from the other side (e.g., the left side). Fig.14 and Fig.15 “(Gr–Gb) / Ave(Gr, Gb) [%]” shown on the vertical axis of the graph in represents a step (ie, “LCR”) between green pixels and blue pixels due to color mixing occurring when red light is irradiated. Fig.14 The curve Coc3 shown represents the LCR characteristics in the case where the structure of the optical black is frame-shaped and its line width is 600 nm. Fig.14The curve Coc4 shown represents the LCR characteristics in the case where the structure of the optical black is a lattice and its line width is 400 nm. Fig.15 The curve Coe3 shown represents the LCR characteristics in the case where the structure of the optical black is frame-shaped and its line width is 600 nm. Fig.15 The curve Coe4 shown represents the LCR characteristics when the structure of the optical black is a grid shape and its line width is 400nm. The frame shape has the same structure as the "frame shape" shown in the "OPB structure" column in Table 1, and the grid shape has the same structure as the "grid shape" shown in the "OPB structure" column in Table 1.

[0164] like Fig.14 As shown in FIG. 1 , the LCR characteristics of the central portion of the pixel region of the solid-state imaging device are such that when the incident direction is within the range of -15° to +35°, the LCR is almost the same when the optical black structure is in a grid shape and a frame shape, and when the incident angle is within the range of -60° to -15° and +35° to +60°, the LCR when the optical black structure is in a frame shape is higher than the LCR when the optical black structure is in a grid shape. Fig.15 As shown, the LCR characteristics of the ends in the longitudinal direction of the pixel area of ​​the solid-state imaging device are as follows: in the range of the incident direction of 0° to +50°, when the structure of the optical black is grid-shaped and frame-shaped, the LCR is almost the same, and in the range of the incident angle of -60° to 0° and +50° to +60°, when the structure of the optical black is frame-shaped, the LCR is higher than the LCR when the structure of the optical black is grid-shaped.

[0165] As described above, even if the solid-state imaging device 1d does not have a second light-shielding area, if the width of the first light-shielding area 31 is determined based on the relationship shown in expressions (1) and (2) (i.e., the aspect ratio of the pixel 2 in the depth direction) and the incident direction of the incident light is within a predetermined range, the sensitivity can be improved while preventing color mixing.

[0166] As described above, the solid-state imaging device 1d according to the present embodiment includes a red pixel 2R having a red filter 22R and a photoelectric conversion unit 21R, a green pixel 2G having a green filter 22G and a photoelectric conversion unit 21G, a blue pixel 2B having a blue filter 22B and a photoelectric conversion unit 21B, and a first light-shielding area 31 arranged between the green pixel 2G and the blue pixel 2B, and between the green pixel 2G and the red pixel 2R.

[0167] In the solid-state image pickup device 1 d having the above-described configuration, color mixing between pixels 2 having different colors can be prevented by the first light shielding region 31 , and thus degradation of image quality can be suppressed.

[0168] In addition, in the solid-state imaging device 1d, no light shielding region is provided in the inner region of the red pixel 2R, the green pixel 2G, and the blue pixel 2B, but the width of the first light shielding region 31 is set to satisfy the above expressions (1) and (2). As a result, the solid-state imaging device 1d can improve sensitivity while preventing color mixing.

[0169] [Fifth embodiment]

[0170] Will refer to Fig.16 and Fig.17 A solid-state imaging device according to a fifth embodiment of the present disclosure is described. The solid-state imaging device 1e according to the present embodiment is characterized in that it includes an insulating film formed between the red pixel 2R and the green pixel 2G, and between the green pixel 2G and the blue pixel 2B. In the description of the present embodiment, constituent elements having the same operation and function as the solid-state imaging device 1a according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

[0171] Since the solid-state imaging device 1e according to the present embodiment has the same overall configuration as the solid-state imaging device 1a according to the first embodiment, its description will be omitted. In addition, the solid-state imaging device 1e can include any one of the first light shielding region 31 and the second light shielding region 32 (except the solid-state imaging device 1d) provided in the solid-state imaging devices 1a, 1b, 1c, and 1d according to the first to fourth embodiments. Fig.16 and Fig.17 , a solid-state imaging device 1e is shown which has a first light shielding region 31 and a second light shielding region 32 like the solid-state imaging device 1a.

[0172] like Fig.16 As shown, the solid-state imaging device 1e includes an insulating film 41 formed between a green pixel (an example of a first pixel) 2G and a blue pixel (an example of a second pixel) 2B so as to overlap with the first light shielding region 31. In addition, although not shown, the insulating film 41 is also formed between the green pixel 2G and the red pixel (an example of a second pixel) 2R so as to overlap with the first light shielding region 31. In addition, the solid-state imaging device 1e has an element separation portion 40 including an insulating film 41, which is formed between the green pixel 2G and the blue pixel 2B, and between the green pixel 2G and the red pixel 2R. Hereinafter, the construction of the element separation portion 40 formed between the green pixel 2G and the blue pixel 2B will be described by taking the element separation portion 40 formed between the green pixel 2G and the blue pixel 2B as an example.

[0173] like Fig.16As shown, the element separation section 40 has a fixed charge film 42 and an insulating film 41, which are formed by being embedded in a groove section 43 formed in the depth direction from the back side of the substrate 12 in sequence. The element separation section 40 is formed by engraving in the pixel separation section 26 formed in the substrate 12. The element separation section 40 is formed in a lattice shape to surround a plurality of pixels 2. When viewed from a direction orthogonal to the layer in which the red filter 22R, the green filter 22G, and the blue filter 22B are formed, the element separation section 40 is arranged below the first light shielding region 31 and the second light shielding region 32. In addition, the element separation section 40 is arranged to overlap with the FD sections 30R, 30G, and 30B in a portion arranged below the second light shielding region 32.

[0174] The element separation portion 40 is formed at a depth that reaches the p-well layer 29 in which the pixel transistor is formed but does not reach the FD portions 30R, 30G, and 30B. When the depth of each of the FD portions 30R, 30G, and 30B is less than 1 μm, the element separation portion 40 can be formed at a depth of approximately 0.25 μm to 5.0 μm from the surface of the substrate 12. In the present embodiment, the element separation portion 40 is formed at a depth that reaches the p-well layer 29 of the pixel transistor, but it is sufficient that the end of the element separation portion 40 on the back side of the substrate 12 is formed to be in contact with the p-type semiconductor layer, and the element separation portion 40 does not necessarily have to be deep enough to reach the p-well layer 29. As in the present embodiment, in the case where the element separation portion 40 is formed in the pixel separation portion 26 made of the p-type semiconductor layer, the effect of insulation separation can be obtained even if the element separation portion 40 does not reach the p-well layer 29.

[0175] In addition, the fixed charge film 42 formed in the groove portion 43 is formed on the inner peripheral surface and the bottom surface of the groove portion 43, and is formed on the entire back surface of the substrate 12. Hereinafter, the inner peripheral surface and the bottom surface of the groove portion 43 are collectively referred to as "inner wall surface". The fixed charge film 42 can be formed of a material that can generate fixed charges and strengthen pinning by deposition on a substrate such as silicon, and a high refractive index material film or a high dielectric film with negative charge can be used. As a specific material for forming the fixed charge film 42, for example, an oxide or nitride containing at least one element of hafnium (Hf), aluminum (Al), zirconium (Zr), tantalum (Ta) and titanium (Ti) can be applied. Examples of the film forming method of the fixed charge film 42 include chemical vapor deposition (hereinafter referred to as CVD method), sputtering method and atomic layer deposition method (hereinafter referred to as ALD method) and the like. When the fixed charge film 42 is formed using the ALD method, a SiO2 film with a film thickness of about 1 nm can be formed at the same time, and the SiO2 film reduces the interface energy level during film formation. Examples of materials other than the above materials for forming the fixed charge film 42 include oxides or nitrides containing at least one element of lanthanum (La), praseodymium (Pr), cerium (Ce), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), thulium (Tm), ytterbium (Yb), lutetium (Lu), and yttrium (Y), etc. In addition, the fixed charge film 42 can be formed of a hafnium oxynitride film or an aluminum oxynitride film.

[0176] As long as the insulating property is not impaired, silicon (Si) or nitrogen (N) may be added to the material for forming the fixed charge film 42 during film formation. As long as the insulating property of the film is not impaired, the concentration of the additive added to the fixed charge film 42 is appropriately determined. By adding silicon (Si) or nitrogen (N) to the fixed charge film 42, the heat resistance of the fixed charge film 42 and the ability to prevent ion implantation in its process can be improved.

[0177] In the present embodiment, a fixed charge film 42 having a negative charge is formed on the inner wall surface of the groove portion 43 and the back surface of the substrate 12, so that an inversion layer is formed on the surface in contact with the fixed charge film 42. As a result, the silicon interface is pinned by the inversion layer, thereby suppressing the generation of dark current. In addition, in the case where the groove portion 43 is formed in the substrate 12, there is a problem that physical damage occurs on the side wall and bottom surface of the groove portion 43, and pinning detachment may occur in the peripheral portion of the groove portion 43. In order to solve this problem, the solid-state imaging device 1e is capable of preventing pinning detachment by forming a fixed charge film 42 having a large amount of fixed charge on the side wall and bottom surface of the groove portion 43.

[0178] The insulating film 41 is embedded in the groove portion 43 in which the fixed charge film 42 is formed, and is formed on the entire surface of the back side of the substrate 12. The insulating film 41 is preferably made of a material having a refractive index different from that of the fixed charge film 42. Examples of the forming material of the insulating film 41 include silicon oxide, silicon nitride, silicon nitride oxide, or resin, etc. In addition, the insulating film 41 may be formed of a material having no positive fixed charge or having a small amount of positive fixed charge.

[0179] When the insulating film 41 is embedded in the groove portion 43, the photoelectric conversion unit 21R provided in the red sub-pixel 20R, the photoelectric conversion unit 21G provided in the green sub-pixel 20G, and the photoelectric conversion unit 21B provided in the blue sub-pixel 20B are separated from each other via the insulating film 41. As a result, it is difficult for the signal charge to leak to the adjacent sub-pixels. Therefore, in the case of generating a signal charge exceeding the saturation charge amount (Qs), the insulating film 41 can reduce the leakage of the overflowing signal charge to the adjacent photoelectric conversion units 21R, 21G, and 21B. In this way, the insulating film 41 can suppress electronic color mixing.

[0180] In addition, the two-layer structure of the fixed charge film 42 and the insulating film 41 formed on the back side as the incident surface side of the substrate 12 has a function as an anti-reflection film due to the difference in refractive index between the fixed charge film 42 and the insulating film 41. This prevents light entering from the back side of the substrate 12 from being reflected on the back side of the substrate 12.

[0181] As described above, the solid-state imaging device 1e has a structure for digging trenches (ie, the groove portions 43) between the pixels 2 from the back side of the substrate 12 (reverse deep trench isolation: RDTI). Fig.17 The effect of the solid-state imaging device 1e is described. Light entering the solid-state imaging device 1e is refracted at the surface of the lens on the chip or at the interface where different components are in contact with each other, but Fig.17 In order to facilitate understanding, the refraction of light is not shown. Fig.17 In FIG. 1 , for ease of understanding, a light shielding region 33 provided in a solid-state imaging device of the related art, which is not originally provided in the solid-state imaging device 1 e , is shown instead of a part of the first light shielding region 31 .

[0182] like Fig.17 As shown, in the case where light L1 having a low incident angle enters the photoelectric conversion unit 21B via, for example, the on-chip lens 23B and the blue filter 22B, the light L1 is reflected by the insulating film 41. Therefore, the light L1 entering the photoelectric conversion unit 21B does not enter the photoelectric conversion unit 21G (not shown) of the green sub-pixel 20G arranged next to the blue sub-pixel 20B having the photoelectric conversion unit 21B. As a result, the solid-state imaging device 1e can prevent color mixing.

[0183] Incidentally, the light shielding region 33 of the related art has a narrower width than the first light shielding region 31 and the second light shielding region 32. Therefore, for example, light L2 incident on the light shielding region 33 via the on-chip lens 23G and the green filter 22G at a high incident angle passes through the light shielding region 33 and enters the photoelectric conversion unit 21B of the blue sub-pixel 20B arranged next to the green sub-pixel 20G having the green filter 22G. This causes color mixing in the solid-state imaging device of the related art.

[0184] On the other hand, the first light shielding region 31 has a width wider than the light shielding region 33 of the related art. Therefore, for example, light L2 incident on the first light shielding region 31 via the on-chip lens 23B and the blue filter 22B at a high incident angle is reflected instead of passing through the first light shielding region 31. As a result, the light L2 enters the photoelectric conversion unit 21B of the blue sub-pixel 20B having the blue filter 22B instead of entering the green sub-pixel 20G (not shown) arranged next to the blue sub-pixel 20B having the blue filter 22B. As a result, the solid-state imaging device 1e is able to prevent color mixing. In addition, since the first light shielding region 31 has a width wider than the light shielding region 33 of the related art, the alignment margin with the element separation portion 40 including the insulating film 41 becomes larger. As a result, the manufacturing yield of the solid-state imaging device 1e can be improved, and the cost of the solid-state imaging device 1e can be reduced.

[0185] As described above, the solid-state imaging device 1e according to the present embodiment includes the insulating film 41 formed between the green pixel 2G and the blue pixel 2B to overlap the first light shielding region 31. The insulating film 41 is also formed between the green pixel 2G and the red pixel 2R to overlap the first light shielding region 31.

[0186] In the solid-state image pickup device 1 e having the above-described configuration, light can be prevented from entering sub-pixels having different colors by the insulating film 41 and color mixing between the pixels 2 can be prevented, so degradation of image quality can be suppressed.

[0187] [Sixth embodiment]

[0188] Will refer to Fig.18 A solid-state imaging device according to a sixth embodiment of the present disclosure is described. The solid-state imaging device 1f according to the present embodiment is characterized in that it has a large-sized wall structure. In the description of the present embodiment, constituent elements having the same operation and function as the solid-state imaging device 1a according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

[0189] Since the solid-state imaging device 1f according to the present embodiment has the same overall configuration as the solid-state imaging device 1a according to the first embodiment, its description will be omitted. In addition, like the solid-state imaging device 1d according to the fourth embodiment, the solid-state imaging device 1f includes the first light shielding region 31 but does not include the second light shielding region 32.

[0190] Fig.18 2G is a diagram schematically showing a cross section of a green pixel 2G. Fig.18 The starting point side (upper side) of the thick arrow shown in FIG. 1 shows a green pixel 200G and a blue pixel 200B provided in a solid-state imaging device having a large-size wall structure of the prior art as a comparative example. The end point side (lower side) of the thick arrow shows a green pixel 2G and a blue pixel 2B provided in a solid-state imaging device 1f according to the present embodiment. Light entering the solid-state imaging device 1f is refracted at the surface of the lens on the chip or at the interface where different constituent elements contact each other, but Fig.18 In the figure, for ease of understanding, the refraction of light is not shown.

[0191] like Fig.18 As shown in the lower side of FIG. 1 , the solid-state imaging device 1f includes a metal film 34 formed between a green filter (an example of a first color filter) 22G, a blue filter (an example of a second color filter) 22B, and a first light shielding region 31 so as to overlap with the first light shielding region 31. The green pixel (an example of a first pixel) 2G has an internal lens 50G (an example of an internal lens) arranged so as to overlap with each of the multiple on-chip lenses 23G between the green filter 22G and the multiple photoelectric conversion units 21Ga, 21Gb, 21Gc, and 21Gd. In addition, the blue pixel (an example of a second pixel) 2B has an internal lens 50B (an example of an internal lens) arranged so as to overlap with each of the multiple on-chip lenses 23B between the blue filter 22B and the multiple photoelectric conversion units 21Ba, 21Bb, 21Bc, and 21Bd.

[0192] Although not shown, the solid-state imaging device 1f includes a metal film formed between the green filter 22G, the red filter (an example of a second color filter) 22R, and the first light shielding region 31 so as to overlap with the first light shielding region 31. The red pixel (an example of a second pixel) 2R has an internal lens (an example of an internal lens) arranged between the red filter 22R and the plurality of photoelectric conversion units 21Ra, 21Rb, 21Rc, and 21Rd so as to overlap with each of the plurality of on-chip lenses 23R.

[0193] When viewed from a direction orthogonal to the green filter 22G, the first light shielding region 31 and the metal film 34 are arranged to overlap each other. The metal film 34 is formed to be in contact with the first light shielding region 31. As a forming material of the metal film 34, for example, tungsten (W), aluminum (Al), or copper (Cu) can be used as with the first light shielding region 31.

[0194] like Fig.18 As shown in the upper side of , the solid-state imaging device of the prior art further has a metal film 35 between the green sub-pixels 201G compared to the solid-state imaging device 1f. In addition, the solid-state imaging device of the prior art has a light shielding region 33 having a width narrower than that of the first light shielding region 31. The light shielding region 33 is also formed below the metal film 34.

[0195] The light shielding region 33 provided in the solid-state imaging device of the related art has a width narrower than that of the first light shielding region 31. Fig.18 As shown on the upper side of FIG. 1 , part of the light L1 entering the green pixel 200G enters the photoelectric conversion unit 21B of the blue pixel 200B arranged next to the green pixel 200G. This causes color mixing in the solid-state imaging device of the related art.

[0196] On the other hand, the solid-state imaging device 1f has the first light shielding region 31 having a width wider than the light shielding region 33. Fig.18 As shown in the lower side of FIG. 1 , part of the light L1 entering the green pixel 2G is reflected by the first light shielding area 31 and thus does not enter the photoelectric conversion unit 21B of the blue pixel 2B arranged next to the green pixel 2G. As a result, the solid-state imaging device 1f can prevent color mixing.

[0197] As described above, even if the solid-state imaging device 1f according to the present embodiment has a large-sized wall structure, color mixing between pixels 2 having different colors can be prevented by the first light shielding region 31, and thus degradation of image quality can be suppressed.

[0198] [Seventh embodiment]

[0199] Will refer to Fig.19 A solid-state imaging device according to a seventh embodiment of the present disclosure is described. A solid-state imaging device 1g according to this embodiment is characterized in that the width of the first light shielding region varies depending on the position of the pixel region. In the description of this embodiment, constituent elements having the same operation and function as those of the solid-state imaging device 1a according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

[0200] Since the solid-state imaging device 1g according to the present embodiment has the same overall configuration as the solid-state imaging device 1a according to the first embodiment, its description will be omitted. In addition, the solid-state imaging device 1g includes a pixel 2 having the same configuration as the pixel 2 provided in the solid-state imaging device 1a according to the first embodiment, except for the width of the first light shielding region.

[0201] like Fig.19 As shown, the solid-state imaging device 1g according to the present embodiment includes a pixel region 3 having a rectangular shape that is longer in the horizontal direction than in the vertical direction and having green pixels (an example of a first pixel) 2G and red pixels 2R and blue pixels 2B (both of which are examples of a second pixel) arranged in a predetermined pattern (for example, a Bayer array) in the vertical direction and the horizontal direction. The vertical direction of the pixel region 3 is, for example, parallel to the vertical signal line 9a (refer to Figure 1 ) is substantially parallel to the direction of the pixel region 3. The horizontal direction of the pixel region 3 is parallel to the selection signal line 9b (refer to Figure 1 ) in a direction roughly parallel to the direction of the

[0202] The width of the portion of the first light shielding region 31 arranged at the short side end of the pixel region 3 parallel to the vertical direction of the pixel region 3 is wider than the width of the portion parallel to the horizontal direction of the pixel region 3. Specifically, Fig.19 As shown in the area 3A in FIG. 1 , the portion of the first light shielding area 31 arranged at the end of the short side of the pixel area 3 and parallel to the vertical direction of the pixel area 3 has a width wider than the second light shielding area 32. On the other hand, the portion of the first light shielding area 31 arranged at the end of the short side of the pixel area 3 and parallel to the horizontal direction of the pixel area 3 has the same width as the second light shielding area 32.

[0203] The width of the first light shielding region 31 arranged in the center of the pixel region 3 is narrower than the width of the portion of the first light shielding region 31 arranged at the short side end of the pixel region 3 parallel to the vertical direction of the pixel region 3. Fig.19 As shown in the region 3B in FIG. 3 , the width of the first light shielding region 31 arranged in the central portion of the pixel region 3 is narrower than the width of the portion of the first light shielding region 31 shown in the region 3A which is parallel to the vertical direction of the pixel region 3. For example, the first light shielding region 31 arranged in the central portion of the pixel region 3 has the same width as the second light shielding region 32.

[0204] For example, the solid-state imaging device 1g may have a first light shielding region 31 formed in point symmetry with the midpoint of the pixel region 3 as an axis of symmetry. In the case where the pixel region 3 has a horizontally long shape, color mixing is more likely to occur at the ends of the short sides than in the center for oblique incidence. Therefore, the solid-state imaging device 1g can improve the resistance to color mixing for oblique incidence by making the line width of the first light shielding region 31 at the ends of the short sides wider than the line width of the first light shielding region 31 in the center. In addition, in the solid-state imaging device 1g, since the width of the first light shielding region 31 is wider only in the region where color mixing may occur with respect to oblique incidence, the amount of reflected light of the incident light in the entire pixel region 3 can be reduced, thereby improving the sensitivity.

[0205] In addition, the width of the first light shielding region 31 may be formed to gradually widen from the central portion toward the short side end portion of the pixel region 3. In this case, compared with the case where the width of all the first light shielding regions 31 provided in the pixel region 3 is wider than the width of the second light shielding region 32, the amount of reflected light of the incident light in the entire pixel region 3 can be reduced, and thus the solid-state imaging device 1g can improve sensitivity.

[0206] As described above, the solid-state imaging device 1g according to the present embodiment can improve the color mixture resistance against oblique incidence, and thus can suppress the degradation of image quality. In addition, the solid-state imaging device 1g can improve the sensitivity.

[0207] [Eighth Embodiment]

[0208] Will refer to Fig. 20 A solid-state imaging device according to an eighth embodiment of the present disclosure is described. A solid-state imaging device 1h according to this embodiment is characterized in that the width of the first light shielding region varies depending on the position of the pixel region. In the description of this embodiment, constituent elements having the same operation and function as those of the solid-state imaging device 1a according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

[0209] Since the solid-state imaging device 1h according to the present embodiment has the same overall configuration as the solid-state imaging device 1a according to the first embodiment, its description will be omitted. In addition, the solid-state imaging device 1h includes a pixel 2 having the same configuration as the pixel 2 provided in the solid-state imaging device 1a according to the first embodiment, except for the width of the first light shielding region.

[0210] like Fig. 20As shown, the solid-state imaging device 1h according to the present embodiment includes a pixel region 3 having a rectangular shape that is longer in the horizontal direction than in the vertical direction and having green pixels (an example of a first pixel) 2G and red pixels 2R and blue pixels 2B (both of which are examples of a second pixel) arranged in a predetermined pattern (for example, a Bayer array) in the vertical direction and the horizontal direction. The vertical direction of the pixel region 3 is, for example, parallel to the vertical signal line 9a (refer to Figure 1 ) is substantially parallel to the direction of the pixel region 3. The horizontal direction of the pixel region 3 is parallel to the selection signal line 9b (refer to Figure 1 ) in a direction roughly parallel to the direction of the

[0211] In the solid-state imaging device 1h, the width of the first light shielding region 31 arranged at the corner of the pixel region 3 is wider than the width of the first light shielding region 31 arranged at the center of the pixel region 3. Specifically, Fig. 20 As shown in the regions 3C and 3B in FIG. 3 , the width of the first light shielding region 31 arranged at the corner of the pixel region 3 (see region 3C) is wider than the width of the first light shielding region 31 arranged at the center of the pixel region 3 (see region 3B). For example, the first light shielding region 31 arranged at the corner of the pixel region 3 has a width wider than the second light shielding region 32. On the other hand, for example, the first light shielding region 31 arranged at the center of the pixel region 3 has the same width as the second light shielding region 32.

[0212] In addition, in the solid-state imaging device 1h, the first light shielding region 31 disposed at the short side end portion of the pixel region 3 excluding the corner portion has a width parallel to the vertical direction of the pixel region 3 that is wider than the width parallel to the horizontal direction of the pixel region 3. Specifically, Fig. 20 As shown in the region 3A in FIG. 1 , the width of the portion of the first light shielding region 31 arranged at the short side end portion of the pixel region 3 excluding the corner portion and parallel to the vertical direction of the pixel region 3 is wider than the width of the portion parallel to the horizontal direction of the pixel region 3. For example, the portion of the first light shielding region 31 arranged at the short side end portion of the pixel region 3 excluding the corner portion and parallel to the vertical direction of the pixel region 3 has a width wider than the second light shielding region 32. On the other hand, for example, the portion of the first light shielding region 31 arranged at the short side end portion of the pixel region 3 excluding the corner portion and parallel to the horizontal direction of the pixel region 3 has the same width as the second light shielding region 32.

[0213] In addition, in the solid-state imaging device 1h, the width of the first light shielding region 31 arranged at the long side end of the pixel region 3 excluding the corner portion is narrower than the width of the portion parallel to the horizontal direction of the pixel region 3. Specifically, Fig. 20As shown in the region 3D in FIG. 3 , the width of the portion of the first light shielding region 31 arranged at the end portion of the long side of the pixel region 3 except the corner portion and parallel to the vertical direction of the pixel region 3 is narrower than the width of the portion parallel to the horizontal direction of the pixel region 3. For example, the portion of the first light shielding region 31 arranged at the end portion of the long side of the pixel region 3 except the corner portion and parallel to the horizontal direction of the pixel region 3 has a width wider than the second light shielding region 32. On the other hand, for example, the portion of the first light shielding region 31 arranged at the end portion of the long side of the pixel region 3 except the corner portion and parallel to the vertical direction of the pixel region 3 has the same width as the second light shielding region 32.

[0214] In addition, in the solid-state imaging device 1h, the width of the first light shielding region 31 arranged in the central portion of the pixel region 3 is narrower than the width of the portion of the first light shielding region 31 arranged in the long side end portion of the pixel region 3 excluding the corner portion and parallel to the horizontal direction of the pixel region 3. Specifically, Fig. 20 As shown in regions 3B, 3C, and 3D in FIG. 3 , for example, the width of the first light shielding region 31 arranged in the central portion of the pixel region 3 (see region 3B) is substantially the same as the width of the second light shielding region 32. For example, the portion of the first light shielding region 31 arranged at the end portion (see region 3D) of the long side of the pixel region 3 other than the corner portion (see region 3C) parallel to the horizontal direction of the pixel region 3 has a width wider than the second light shielding region 32. Therefore, the first light shielding region 31 arranged in the central portion of the pixel region 3 has a width narrower than the width of the portion of the first light shielding region 31 arranged at the end portion of the long side of the pixel region 3 other than the corner portion parallel to the horizontal direction of the pixel region 3. Therefore, the width of the first light shielding region 31 arranged in the central portion of the pixel region 3 is narrower than the width of the portion of the first light shielding region 31 arranged at the end portion of the long side of the pixel region 3 other than the corner portion parallel to the horizontal direction of the pixel region 3.

[0215] In addition, in the solid-state imaging device 1h, the width of the first light shielding region 31 arranged in the central portion of the pixel region 3 is narrower than the width of the portion of the first light shielding region 31 arranged in the short side end portion of the pixel region 3 excluding the corner portion and parallel to the vertical direction of the pixel region 3. Specifically, Fig. 20As shown in the regions 3A, 3B, and 3C in FIG. 3 , for example, the portion of the first light shielding region 31 arranged at the short side end portion (see region 3A) of the pixel region 3 except the corner portion (see region 3C) parallel to the vertical direction of the pixel region 3 has a width wider than that of the second light shielding region 32. Therefore, the first light shielding region 31 arranged at the central portion (see region 3B) of the pixel region 3 has a width narrower than that of the portion of the first light shielding region 31 arranged at the short side end portion of the pixel region 3 except the corner portion parallel to the vertical direction of the pixel region 3. Therefore, the width of the first light shielding region 31 arranged at the central portion of the pixel region 3 is narrower than that of the portion of the first light shielding region 31 arranged at the short side end portion of the pixel region 3 except the corner portion parallel to the vertical direction of the pixel region 3.

[0216] The solid-state imaging device 1h may have, for example, a first light shielding region 31 formed in point symmetry with the midpoint of the pixel region 3 as an axis of symmetry. In the solid-state imaging device, although pupil correction is applied, the main light from the on-chip lenses 23R, 23G, and 23B is tilted, so color mixing increases at high image heights. Therefore, in the solid-state imaging device 1h according to the present embodiment, the width of the first light shielding region 31 becomes wider as the image height becomes higher (i.e., the corners, long side ends, and short side ends of the pixel region 3). In addition, in the solid-state imaging device 1h, since the width of the first light shielding region 31 is wider only in the region where color mixing is likely to occur with respect to oblique incidence, the amount of reflected light of the incident light in the entire pixel region 3 can be reduced, thereby improving the sensitivity.

[0217] As described above, the solid-state imaging device 1h according to the present embodiment can improve the color mixture resistance for high image height, and thus can suppress the degradation of image quality. In addition, the solid-state imaging device 1h can improve the sensitivity.

[0218] Although the present disclosure has been described above by taking various embodiments as examples, the present disclosure is not limited to the above embodiments, etc., and various modifications may be made. The effects described in this specification are merely examples. The effects of the present disclosure are not limited to the effects described in this specification. The present disclosure may have effects other than those described in this specification.

[0219] Furthermore, for example, the present disclosure may have the following configurations. (1)

[0221] A solid-state imaging device comprising:

[0222] a first pixel having a plurality of on-chip lenses and a plurality of photoelectric conversion units that share a first color filter with each other;

[0223] a second pixel disposed adjacent to the first pixel and having a plurality of on-chip lenses and a plurality of photoelectric conversion units that share a second color filter with each other; and

[0224] The first light shielding area is arranged between the first pixel and the second pixel. (2)

[0226] According to the solid-state imaging device described in (1),

[0227] wherein the first pixel includes a first sub-pixel having a first photoelectric conversion unit among the plurality of photoelectric conversion units, a second sub-pixel having a second photoelectric conversion unit among the plurality of photoelectric conversion units, and a second light shielding region disposed between the first sub-pixel and the second sub-pixel, and

[0228] The width of the second light-shielding area is narrower than that of the first light-shielding area. (3)

[0230] The solid-state imaging device according to (2), wherein, in a case where the first color filter has a color with lower visual sensitivity than the second color filter, the second light shielding region is provided in the first pixel. (4)

[0232] The solid-state imaging device according to (2) or (3), wherein, when the first color filter is a color filter having a color with a longer wavelength than that of the second color filter, the second light shielding area is provided in the first pixel. (5)

[0234] A solid-state imaging device according to (1), wherein the second pixel includes a first sub-pixel having a first photoelectric conversion unit among the plurality of photoelectric conversion units and a second sub-pixel having a second photoelectric conversion unit among the plurality of photoelectric conversion units, and there is no light-shielding area between the first sub-pixel and the second sub-pixel. (6)

[0236] The solid-state imaging device according to any one of (1) to (5),

[0237] Wherein, when the width of the first shading area is defined as w,

[0238] The pitch between the plurality of on-chip lenses in the first pixel is defined as p1,

[0239] A height from a virtual plane including the bottom surface of the first light shielding region to the top of the on-chip lens of the first pixel closest to the first light shielding region is defined as h1, and

[0240] When the length of light entering the photoelectric conversion unit provided in the first pixel is defined as d1,

[0241] The following relationship is satisfied:

[0242] w>2×((p1 / 2)×d1 / (h1+d1)). (7)

[0244] The solid-state imaging device according to any one of (1) to (6),

[0245] Wherein, when the width of the first shading area is defined as w,

[0246] The pitch between the plurality of on-chip lenses in the second pixel is defined as p2,

[0247] A height from a virtual plane including the bottom surface of the first light shielding region to the top of the on-chip lens of the second pixel closest to the first light shielding region is defined as h2, and

[0248] When the length of light entering the photoelectric conversion unit provided in the second pixel is defined as d2,

[0249] The following relationship is satisfied:

[0250] w>2×((p2 / 2)×d2 / (h2+d2)). (8)

[0252] The solid-state imaging device according to any one of (1) to (7), further including an insulating film formed between the first pixel and the second pixel so as to overlap with the first light shielding region. (9)

[0254] The solid-state imaging device according to any one of (1) to (8), further comprising a metal film formed between the first color filter, the second color filter, and the first light shielding region so as to overlap with the first light shielding region,

[0255] wherein the first pixel has a plurality of internal lenses arranged between the first color filter and the plurality of photoelectric conversion units so as to overlap with each of the plurality of on-chip lenses, and

[0256] The second pixel has a plurality of internal lenses arranged between the second color filter and the plurality of photoelectric conversion units so as to overlap with each of the plurality of on-chip lenses. (10)

[0258] The solid-state imaging device according to any one of (1) to (9), further comprising a pixel region having a rectangular shape that is longer in the horizontal direction than in the vertical direction and having the first pixels and the second pixels arranged in a predetermined pattern in the vertical direction and the horizontal direction,

[0259] The width of a portion of the first light shielding region arranged at an end portion of a short side of the pixel region parallel to the vertical direction is wider than the width of a portion parallel to the horizontal direction. (11)

[0261] A solid-state imaging device according to (10), wherein the width of the first light shielding region arranged in the central portion of the pixel region is narrower than the width of the portion of the first light shielding region arranged at the short side end portion of the pixel region parallel to the vertical direction. (12)

[0263] The solid-state imaging device according to any one of (1) to (9), further comprising a pixel region having a rectangular shape that is longer in the horizontal direction than in the vertical direction and having the first pixels and the second pixels arranged in a predetermined pattern in the vertical direction and the horizontal direction,

[0264] The width of the first light shielding region arranged at the corner of the pixel region is wider than the width of the first light shielding region arranged at the center of the pixel region. (13)

[0266] A solid-state imaging device according to (12), wherein a portion of the first light shielding region arranged at a short side end portion of the pixel region excluding the corner portion, which is parallel to the vertical direction, has a width wider than a portion parallel to the horizontal direction. (14)

[0268] A solid-state imaging device according to (12) or (13), wherein the width of a portion of the first light shielding region arranged at the long side end portion of the pixel region other than the corner portion parallel to the vertical direction is narrower than the width of a portion parallel to the horizontal direction. (15)

[0270] A solid-state imaging device according to (13), wherein the width of the first light shielding region arranged in the central portion of the pixel region is narrower than the width of a portion of the first light shielding region parallel to the horizontal direction arranged at the end portions of the long sides of the pixel region excluding the corners. (16)

[0272] A solid-state imaging device according to (13), wherein the width of the first light shielding region arranged in the central portion of the pixel region is narrower than the width of the portion parallel to the vertical direction of the first light shielding region arranged at the short side end portion of the pixel region excluding the corner portion.

[0273] Those skilled in the art can conceive various modifications, combinations, sub-combinations and alterations according to design requirements and other factors, but it should be understood that these modifications, combinations, sub-combinations and alterations are all included in the scope of the appended claims and their equivalents.

[0274] Reference numerals list

[0275] 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h Solid-state imaging device

[0276] 2 pixels

[0277] 2B, 200B blue pixels

[0278] 2G, 200G Green Pixels

[0279] 2R Red Pixel

[0280] 3 pixel area

[0281] Areas 3A, 3B, 3C, 3D

[0282] 4 Vertical drive circuit

[0283] 5 columns of signal processing circuits

[0284] 6 Horizontal drive circuit

[0285] 7 Output Circuit

[0286] 8 Control circuit

[0287] 9a Vertical signal line

[0288] 9b Select signal line

[0289] 10 Horizontal signal line

[0290] 11 Support substrate

[0291] 12 substrate

[0292] 13 Wiring layer

[0293] 14 Interlayer insulation film

[0294] 15 Wiring

[0295] 17 Gate insulation film

[0296] 20B blue sub-pixel

[0297] 20G, 201G Green sub-pixel

[0298] 20R red sub-pixel

[0299] 21B, 21G, 21R Photoelectric conversion unit

[0300] 22B Blue Filter

[0301] 22G Green filter

[0302] 22R Red filter

[0303] 23B, 23G, 23R On-chip lens

[0304] 24 Insulation film

[0305] 25 Flattening film

[0306] 26 Pixel separation unit

[0307] 29 p-well layer

[0308] 30° reverse angle

[0309] 30B, 30G, 30R Floating diffusion (FD)

[0310] 31 First shading area

[0311] 32 Second light shielding area

[0312] 33 Shading area

[0313] 34, 35 metal film

[0314] 40 Component separation unit

[0315] 41 Insulation film

[0316] 42 Fixed Charge Membrane

[0317] 43 Groove

[0318] 50B, 50G internal lens

[0319] 211 n-type semiconductor region

[0320] 212, 213 p-type semiconductor region

[0321] 311 Bottom

[0322] GE Gate Electrode

[0323] GTr2, RTr2 Reset transistor

[0324] GTr3, RTr3 amplifier transistor

[0325] GTr4, RTr4 selection transistor

[0326] GTr11, GTr12, GTr13, GTr14, RTr11, RTr12, RTr13, RTr14 Pass transistor

Claims

1. A solid-state imaging device, comprising: a first pixel having a plurality of on-chip lenses and a plurality of photoelectric conversion units that share a first color filter with each other; a second pixel disposed adjacent to the first pixel and having a plurality of on-chip lenses and a plurality of photoelectric conversion units that share a second color filter with each other; and A first light shielding area is provided between the first pixel and the second pixel, The first pixel includes a first sub-pixel having a first photoelectric conversion unit among the plurality of photoelectric conversion units and a second sub-pixel having a second photoelectric conversion unit among the plurality of photoelectric conversion units. Wherein, when the first color filter has a color with a lower visual sensitivity than the second color filter, a second light shielding area is provided between the first sub-pixel and the second sub-pixel in the first pixel.

2. The solid-state imaging device according to claim 1, in, The width of the second light shielding region is narrower than the width of the first light shielding region.

3. The solid-state imaging device according to claim 1, wherein In the case where the first color filter is a color filter having a color with a longer wavelength than that of the second color filter, the second light shielding region is provided in the first pixel.

4. The solid-state imaging device according to claim 1, wherein The second pixel includes a first subpixel having a first photoelectric conversion unit among the plurality of photoelectric conversion units and a second subpixel having a second photoelectric conversion unit among the plurality of photoelectric conversion units, and has no light shielding region between the first subpixel and the second subpixel.

5. The solid-state imaging device according to claim 1, in, When the width of the first light shielding area is defined as w, The pitch between the plurality of on-chip lenses in the first pixel is defined as p1, A height from a virtual plane including the bottom surface of the first light shielding region to the top of the on-chip lens of the first pixel closest to the first light shielding region is defined as h1, and When the length of light entering the photoelectric conversion unit provided in the first pixel is defined as d1, The following relationship is satisfied: w > 2 × ((p1 / 2) × d1 / (h1 + d1)).

6. The solid-state imaging device according to claim 1, in, When the width of the first light shielding area is defined as w, The pitch between the plurality of on-chip lenses in the second pixel is defined as p2, A height from a virtual plane including the bottom surface of the first light shielding region to the top of the on-chip lens of the second pixel closest to the first light shielding region is defined as h2, and When the length of light entering the photoelectric conversion unit provided in the second pixel is defined as d2, The following relationship is satisfied: w > 2 × ((p2 / 2) × d2 / (h2 + d2)). 7 . The solid-state imaging device according to claim 1 , further comprising an insulating film formed between the first pixel and the second pixel so as to overlap with the first light shielding region.

8. The solid-state imaging device according to claim 1, further comprising a metal film formed between the first color filter, the second color filter, and the first light shielding region so as to overlap with the first light shielding region, in, The first pixel has a plurality of internal lenses arranged between the first color filter and the plurality of photoelectric conversion units so as to overlap with each of the plurality of on-chip lenses, and The second pixel has a plurality of internal lenses arranged between the second color filter and the plurality of photoelectric conversion units so as to overlap with each of the plurality of on-chip lenses.

9. The solid-state imaging device according to any one of claims 1 to 8, further comprising a pixel region having a rectangular shape that is longer in the horizontal direction than in the vertical direction and having the first pixels and the second pixels arranged in a predetermined pattern in the vertical direction and the horizontal direction, in, The width of a portion of the first light shielding region disposed at an end portion on a short side of the pixel region parallel to the vertical direction is wider than that of a portion parallel to the horizontal direction.

10. The solid-state imaging device according to claim 9, wherein: The width of the first light shielding region arranged in the central portion of the pixel region is narrower than the width of the portion of the first light shielding region arranged at the short-side end portion of the pixel region and parallel to the vertical direction.

11. The solid-state imaging device according to any one of claims 1 to 8, further comprising a pixel region having a rectangular shape that is longer in the horizontal direction than in the vertical direction and having the first pixels and the second pixels arranged in a predetermined pattern in the vertical direction and the horizontal direction, in, The width of the first light shielding region disposed at a corner portion of the pixel region is wider than the width of the first light shielding region disposed at a center portion of the pixel region.

12. The solid-state imaging device according to claim 11, wherein The first light shielding region disposed at the end portion of the pixel region on the short side excluding the corner portion has a width of a portion parallel to the vertical direction wider than a width of a portion parallel to the horizontal direction.

13. The solid-state imaging device according to claim 11, wherein The width of a portion of the first light shielding region arranged at a long-side end portion of the pixel region excluding the corner portion and parallel to the vertical direction is narrower than that of a portion of the first light shielding region parallel to the horizontal direction.

14. The solid-state imaging device according to claim 12, wherein: The width of the first light shielding region arranged in the central portion of the pixel region is narrower than the width of a portion of the first light shielding region arranged at a long side end portion of the pixel region excluding the corner portion and parallel to the horizontal direction.

15. The solid-state imaging device according to claim 12, wherein: The width of the first light shielding region arranged in the central portion of the pixel region is narrower than the width of the portion parallel to the vertical direction of the first light shielding region arranged at the short side end portion of the pixel region excluding the corner portion.

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