JP7496406B1 - Solid-state imaging device, manufacturing method thereof, and electronic device - Google Patents

Abstract

[Problem] To provide a solid-state imaging device capable of suppressing a decrease in sensitivity of phase difference pixels even in miniaturized pixels and realizing high phase difference performance with high speed and good focusing performance even in shooting scenes with a low amount of incident light, a manufacturing method thereof, and electronic equipment. [Solution] In a pixel section 20, a phase difference detection pixel group PDXG10 is formed including phase difference detection pixels PDPX of the same color (G) in a number (5 or more) greater than the number (4) of pixels NPX forming a pixel unit PU of normal pixel groups NPXG11, NPXG12, and NPXG14, and is capable of reading out a phase difference detection signal acquired by at least one phase difference detection pixel PDPX in a central region ACTR in the arrangement direction and a signal acquired by a pixel PX in an end region AEDG in the arrangement direction to a floating diffusion FD as the same (common) readout node. [Selected Figure] FIG. 6

Description

The present invention relates to a solid-state imaging device, a method for manufacturing a solid-state imaging device, and an electronic device.

CMOS (Complementary Metal Oxide Semiconductor) image sensors are used as solid-state imaging devices (image sensors) that use photoelectric conversion elements that detect light and generate electric charges.

CMOS image sensors generally capture color images using three primary color filters of red (R), green (G), and blue (B) or four complementary color filters of cyan, magenta, yellow, and green.

Typically, in a CMOS image sensor, each pixel is provided with a color filter, which includes a red (R) filter that transmits mainly red light, a green (Gr, Gb) filter that transmits mainly green light, and a blue (B) filter that transmits mainly blue light.
A pixel group is formed by arranging pixel units each including a color filter in a square, and a plurality of pixel groups are arranged two-dimensionally to form a pixel array of the pixel portion.
The Bayer array is widely known as this color filter array. Also, for example, a microlens is formed for each pixel.
Furthermore, in order to achieve high sensitivity and a wide dynamic range, a CMOS image sensor has been proposed in which each pixel unit in a Bayer array is formed from a plurality of pixels of the same color (see, for example, Patent Documents 1 and 2).

Such CMOS image sensors are widely used as part of various electronic devices, such as digital cameras, video cameras, surveillance cameras, medical endoscopes, personal computers (PCs), mobile terminal devices (mobile devices) such as mobile phones, etc.

Particularly in recent years, image sensors mounted on portable terminal devices (mobile devices) such as mobile phones have become smaller and have more pixels, and pixel sizes of less than 1 μm are becoming mainstream.
In order to maintain the high resolution achieved by increasing the number of pixels and making them finer, while suppressing the loss of sensitivity and dynamic range that occurs due to the reduction in pixel pitch, a method is generally adopted in which multiple adjacent pixels of the same color are arranged in groups of, for example, four pixels, and individual pixel signals are read out when pursuing high resolution, and signals from pixels of the same color are added and read out when high sensitivity and dynamic range performance are required.
In this CMOS image sensor, for example, a single microlens is shared by a plurality of adjacent (2, 4 or 9) pixels of the same color in the pixel unit.

In a solid-state imaging device (CMOS image sensor) in which a single microlens is shared by a plurality of pixels of the same color, distance information exists in the pixel, and it is possible to have a Phase Detection Auto Focus (PDAF) function.
In addition, in this CMOS image sensor, since PDAF (phase detection autofocus) pixels are formed in the same color in the pixel array, in normal shooting mode, it is necessary to correct the sensitivity, shading, etc. of these PDAF pixels.

Figure 1 shows an example of a pixel group in a pixel array of a solid-state imaging device (CMOS image sensor) in which four pixels of the same color share one microlens and which has a PDAF function (see, for example, Patent Document 3).

In the pixel group 1 of FIG. 1, a pixel unit PU1 of Gr pixels, a pixel unit PU2 of R pixels, a pixel unit PU3 of B pixels, and a pixel unit PU4 of Gb pixels are arranged in a Bayer array.
The pixel unit PU1 includes a plurality of adjacent pixels, for example, four 2×2 pixels of the same color (Gr) PXGrA, PXGrB, PXGrC, and PXGrD, arranged in a matrix. In the pixel unit PU1, one microlens MCL1 is arranged for the four pixels PXGrA, PXGrB, PXGrC, and PXGrD.
The pixel unit PU2 includes a plurality of adjacent pixels, for example, 2×2 pixels of the same color (R) PXRA, PXRB, PXRC, and PXRD. In the pixel unit PU2, one microlens MCL2 is provided for the four pixels PXRA, PXRB, PXRC, and PXRD.
The pixel unit PU3 includes a plurality of adjacent pixels, for example, 2×2 pixels of the same color (B) PXBA, PXBB, PXBC, and PXBD. In the pixel unit PU3, one microlens MCL3 is provided for the four pixels PXBA, PXBB, PXBC, and PXBD.
The pixel unit PU4 includes a plurality of adjacent pixels, for example, four 2×2 pixels of the same color (Gb) PXGbA, PXGbB, PXGbC, and PXGbD, arranged in the pixel unit PU4. In the pixel unit PU4, one microlens MCL4 is arranged for the four pixels PXGbA, PXGbB, PXGbC, and PXGbD.

This first solid-state imaging device improves PDAF performance in low illumination conditions because two adjacent pixels simultaneously function as PDAF pixels.

Figure 2 shows an example of a pixel group in a pixel array of a solid-state imaging device (CMOS image sensor) in which two pixels of the same color share one microlens and which has a PDAF function (see, for example, Patent Document 4).

1, the pixel group 1a in FIG. 2 includes a pixel unit PU1 of Gr pixels, a pixel unit PU2 of R pixels, a pixel unit PU3 of B pixels, and a pixel unit PU4 of Gb pixels arranged in a Bayer array.
The pixel unit PU1 includes a plurality of adjacent pixels, for example, four 2×2 pixels of the same color (Gr) PXGrA, PXGrB, PXGrC, and PXGrD, arranged in a pixel unit PU1. In the pixel unit PU1, microlenses MCL01, MCL02, MCL03, and MCL04 are arranged for the four pixels PXGrA, PXGrB, PXGrC, and PXGrD, respectively.
The pixel unit PU2 includes a plurality of adjacent pixels, for example, 2×2 pixels of the same color (R) PXRA, PXRB, PXRC, and PXRD. In the pixel unit PU2, microlenses MCL11, MCL12, MCL13, and MCL14 are disposed for the four pixels PXRA, PXRB, PXRC, and PXRD, respectively.

In the pixel unit PU3, a G pixel PXGB is arranged in place of the B pixel PXBB among four adjacent pixels PXBA, PXBB, PXBC, and PXBD of the same color (B). In the pixel unit PU3, microlenses MCL21, MCL23, and MCL24 are arranged for each of the three pixels PXBA, PXBC, and PXBD.
The pixel unit PU4 includes adjacent 2×2 pixels of the same color (Gb), PXGbA, PXGbB, PXGbC, and PXGbD. In the pixel unit PU4, microlenses MCL32, MCL33, and MCL34 are arranged for each of the three pixels PXGbB, PXGbC, and PXGbD.

In the second solid-state imaging device of FIG. 2, a microlens MCL35 is arranged across the pixel units for pixel PXGB of pixel unit PU3 and pixel PXGbA of pixel unit PU4, and is configured to have a PDAF function.

In this second solid-state imaging device, only one pair of pixels functions as a PDAF pixel, so the low-illumination PDAF performance tends to be poor, but the light-shielding area at the optical center is small, so the light-shielding characteristics and sensitivity ratio characteristics of the peripheral areas are high.

A third type of solid-state imaging device is known in which a microlens is arranged for each pixel in each pixel unit, and one microlens is arranged for every four pixels in a specific pixel unit in the pixel array, for example, a pixel unit having four G pixels instead of four B pixels, and which is configured to have a PDAF function (see, for example, Patent Document 5).

Japanese Patent Application Laid-Open No. 11-298800 Patent No. 5471117 US 9793313 B2 US 10249663 B2 US 9807294 B2

However, in the solid-state imaging device of FIG. 1, two adjacent pixels simultaneously function as PDAF pixels, which increases the sensitivity of the phase difference pixel itself and improves PDAF performance in low illumination. However, there are disadvantages, such as a decrease in sensitivity of the normal pixel (during normal shooting) and increased color mixing with adjacent pixels, due to an increase in the light-shielding area of the optical center.

The solid-state imaging device in Figure 2 also has the problem of degraded autofocus functionality when photographing a subject in low light. However, because a microlens is formed in a one-to-one correspondence with each normal pixel, there is little light collection loss or scattering due to the light-shielding film at the center of light collection. In addition, because there are two types of pixels, normal pixels and phase difference pixels, the sensitivity when photographing normal images and color mixing with adjacent pixels are good.

In addition, in the above-mentioned third solid-state imaging device, since two adjacent pixels simultaneously function as PDAF pixels, the PDAF performance in low illuminance is improved, and since the light-shielding area at the optical center is small, the light-shielding characteristics and sensitivity ratio characteristics of the peripheral parts are high. However, there are the following disadvantages.
This configuration requires two different lens shapes, resulting in a large variation in sensitivity.
In addition, since the PDAF pixel portion is replaced with green (G) instead of blue (B), color correction is required, and the resolution of blue (B) decreases.

In addition, we will consider the issues that arise with miniaturization and miniaturization of pixel size.
As mentioned above, in recent years, pixel sizes have been decreasing along with the miniaturization of camera sets such as smartphones. In order to improve sensitivity degradation, pixel arrays in which multiple pixels of the same color are adjacent to each other have become mainstream.
On the other hand, the autofocus method for camera sets is mainly the PDAF method, which has a fast focusing speed. For the fine pixels of smartphones, the method of providing a phase difference detection function by forming a common microlens on two or four adjacent pixels is mainstream.

However, with the conventional method described above, the number of pixels that can be used for autofocus is at most one or two, and as pixels become finer, the decrease in sensitivity during autofocus becomes an issue.

To improve sensitivity when focusing, a method has been developed in which signals from other phase difference pixels that are relatively close to the relevant phase difference pixel are added during signal processing, but this increases the amount of adding processing, resulting in a drop in frame rate. With this method, there is a trade-off between the autofocus performance (distance measurement performance) that decreases as the distance between the same-phase pixels to be added increases, while moving them closer together results in issues with correction marks left by the signal correction. This makes it difficult to achieve both autofocus performance and image quality (without correction marks).

Furthermore, issues related to autofocus are discussed.
For example, in the third solid-state imaging device as described above, a specific pixel unit in the pixel array, for example a pixel unit having four G pixels instead of four B pixels, is formed as a phase difference detection pixel equivalent to a normal pixel unit in the normal pixel region, and in the pixel unit having four G pixels, one microlens is arranged for every four pixels, and the pixel unit is configured to have a PDAF function.
Furthermore, in the solid-state imaging device of FIG. 2, for example, in a region including a phase difference detection pixel, signals of two or more colors need to be read out to the same floating diffusion FD.

However, in either case, the phase difference detection signal for autofocus control and the pixel signal of the normal pixel cannot be read out simultaneously in parallel, which has the disadvantage that the frame rate slows down, especially when phase difference driving is performed during pixel addition.

The present invention aims to provide a solid-state imaging device, a method for manufacturing a solid-state imaging device, and an electronic device that can suppress a decrease in sensitivity of phase difference detection pixels even in miniaturized pixels, achieve high phase difference performance with high speed and good focusing performance even in shooting scenes with a low amount of incident light, and can read out pixel signals of the same color to the same readout node in a group of phase difference detection pixels with high image quality and without reducing the frame rate.

The solid-state imaging device according to the first aspect of the present invention has a pixel section in which a plurality of pixels including a photoelectric conversion section are arranged in an array, and in the pixel section, a normal pixel group formed by a plurality of pixel units including a plurality of adjacent pixels of the same color and a phase difference detection pixel group formed by including a number of phase difference detection pixels of the same color that is greater than the number of pixels forming the pixel units of the normal pixel group, for detecting phase difference information for controlling a focus function are mixed, and the phase difference detection pixel group is formed so that a plurality of pixels of the same color are extended in at least one direction of a first direction and a second direction perpendicular to the first direction in a matrix form, and includes at least one shared microlens that introduces light into the photoelectric conversion section of at least two of the plurality of phase difference detection pixels in the central region of the arrangement direction, and the phase difference detection signal acquired by at least one phase difference detection pixel in the central region and the signal acquired by the pixel in the end region of the arrangement direction can be read out to the same readout node.

The second aspect of the present invention is a method for manufacturing a solid-state imaging device having a pixel section in which a plurality of pixels including a photoelectric conversion section are arranged in an array, and in the pixel section, a normal pixel group formed by a plurality of pixel units including a plurality of adjacent pixels of the same color and a phase difference detection pixel group formed including a number of phase difference detection pixels of the same color that is greater than the number of pixels forming the pixel units of the normal pixel group, for detecting phase difference information for controlling a focus function are mixed. In the phase difference detection pixel group formation process, a plurality of same-color pixels are formed in a matrix shape so as to extend in at least one direction of a first direction and a second direction perpendicular to the first direction, and at least one shared microlens that introduces light into the photoelectric conversion section of at least two of the plurality of phase difference detection pixels in the central region of the arrangement direction is formed so that the phase difference detection signal acquired by at least one phase difference detection pixel in the central region and the signal acquired by the pixel in the end region of the arrangement direction can be read out to the same readout node.

The electronic device according to the third aspect of the present invention includes a solid-state imaging device and an optical system that forms a subject image on the solid-state imaging device. The solid-state imaging device has a pixel section in which a plurality of pixels including a photoelectric conversion section are arranged in an array. In the pixel section, a normal pixel group formed by a plurality of pixel units including a plurality of adjacent pixels of the same color and a phase difference detection pixel group formed by including a number of phase difference detection pixels of the same color that is greater than the number of pixels forming the pixel units of the normal pixel group, for detecting phase difference information for controlling a focus function are mixed. The phase difference detection pixel group is formed so that a plurality of pixels of the same color are extended in at least one direction of a first direction and a second direction perpendicular to the first direction in a matrix form, and includes at least one shared microlens that introduces light into the photoelectric conversion section of at least two phase difference detection pixels among the plurality of phase difference detection pixels in the central region of the arrangement direction, and the phase difference detection signal acquired by at least one phase difference detection pixel in the central region and the signal acquired by the pixel in the end region of the arrangement direction can be read out to the same readout node.

According to the present invention, it is possible to suppress a decrease in sensitivity of a phase difference detection pixel even in a miniaturized pixel, and it is possible to achieve high phase difference performance with high speed and good focusing performance even in a shooting scene with a low amount of incident light.
Furthermore, according to the present invention, pixel signals of the same color can be read out to the same readout node in a phase difference detection pixel group with high image quality and without decreasing the frame rate.

FIG. 1 is a diagram showing an example of a pixel group in a pixel array of a solid-state imaging device (CMOS image sensor) in which four pixels of the same color share one microlens and which has a PDAF function. 1 is a diagram showing an example of a pixel group in a pixel array of a solid-state imaging device (CMOS image sensor) in which two pixels of the same color share one microlens and which has a PDAF function. 1 is a block diagram showing an example of the configuration of a solid-state imaging device according to a first embodiment of the present invention; 2A to 2C are diagrams illustrating an example of a pixel array in a pixel section according to the first embodiment of the present invention. 1 is a diagram illustrating an example of a pixel group that forms a pixel array according to a first embodiment of the present invention. 2 is a diagram showing an example of a phase difference detection pixel group forming a pixel array according to the first embodiment of the present invention; FIG. FIG. 2 is a diagram showing an example of a pixel array of a phase difference detection pixel group according to the first embodiment of the present invention. 1 is a simplified cross-sectional view showing an example of a phase difference detection pixel group and its adjacent region that form a pixel array according to a first embodiment of the present invention. FIG. 4 is a diagram showing an example of an element isolation unit in a phase difference detection pixel group that forms a pixel array according to the first embodiment of the present invention. FIG. 2 is a circuit diagram showing an example of a pixel unit in which one floating diffusion is shared by four pixels of a pixel group of the solid-state imaging device according to the first embodiment of the present invention. FIG. 13 is a diagram showing an example of formation of a phase difference detection pixel group in a pixel array of a pixel unit according to a second embodiment of the present invention. FIG. FIG. 11 is a simplified cross-sectional view showing an example of a phase difference detection pixel group and its adjacent region that form a pixel array according to a second embodiment of the present invention. 13A to 13C are diagrams illustrating an example of formation of an element isolation portion in a phase difference detection pixel group that forms a pixel array according to a second embodiment of the present invention. 13A to 13C are diagrams illustrating an example of formation of an element isolation portion in a phase difference detection pixel group that forms a pixel array according to a third embodiment of the present invention. 13A and 13B are diagrams illustrating an example of formation of an element isolation portion in a phase difference detection pixel group that forms a pixel array according to a fourth embodiment of the present invention. 13A to 13C are diagrams illustrating an example of formation of an element isolation portion in a phase difference detection pixel group that forms a pixel array according to a fifth embodiment of the present invention. 1 is a diagram showing an example of a configuration of an electronic device to which a solid-state imaging device according to an embodiment of the present invention is applied;

The following describes an embodiment of the present invention with reference to the drawings.

First Embodiment
FIG. 3 is a block diagram showing an example of the configuration of the solid-state imaging device according to the first embodiment of the present invention.
FIG. 4 is a diagram showing an example of forming a pixel array in a pixel section according to the first embodiment of the present invention.
In this embodiment, the solid-state imaging device 10 is formed of, for example, a CMOS image sensor.

As shown in FIG. 3, the solid-state imaging device 10 has as its main components a pixel section 20 including a pixel array, a vertical scanning circuit (row scanning circuit) 30, a readout circuit (column readout circuit) 40, a horizontal scanning circuit (column scanning circuit) 50, and a timing control circuit 60.
Among these components, for example, the vertical scanning circuit 30, the readout circuit 40, the horizontal scanning circuit 50, and the timing control circuit 60 constitute a pixel signal readout drive control unit 70.

In the solid-state imaging device 10 according to the first embodiment, as shown in FIG. 4, the pixel section 20 is formed by arranging a plurality of pixels PX, each including a photoelectric conversion section (PD), in an array (matrix).
In the pixel section 20 of this first embodiment, pixel groups PXG11, PXG12, PXG13, and PXG14 formed by a plurality (four in this example) of pixel units PU each including a plurality (four in this example) of adjacent same-color pixels PX are arranged in a 2 x 2 matrix.
More specifically, the pixel section 20 of this first embodiment is configured to include a normal pixel group NPXG formed by a plurality (four in this example) of pixel units PU including a plurality (four in this example) of adjacent same-color pixels PX, and a phase difference detection pixel group PDXG for detecting phase difference information for controlling the focus function.

In the example of Figure 4, as described below, pixel groups PXG11, PXG12, and PXG14 are applied as normal pixel groups NPXG11, NPXG12, and NPXG14, and a portion of pixel group PXG13 is used as phase difference detection pixel group PDXG10.

The phase difference detection pixel group PDXG10 is formed by including a greater number (five or more, eight in this example) of phase difference detection pixels PDPX of the same color (green (G) in this example) than the number (four) of pixels NPX that form the pixel units PU of the normal pixel groups NPXG11, NPXG12, and NPXG14.

Furthermore, in the normal pixel groups NPXG11, NPXG12, and NPXG14 of this first embodiment, one individual microlens PMCL1 formed to form an approximately circular shape in a planar view is arranged for each pixel NPX that forms each pixel unit PU.
In contrast, the phase difference detection pixel group PDXG10 is arranged such that one shared microlens CMCL10 is formed so as to form an approximately circular shape in a planar view in which light is incident on the photoelectric conversion units of the four phase difference detection pixels PDPX in a central region ACTR in the arrangement direction (first direction in this example) in which the phase difference detection pixel group is formed, and four individual microlenses PMCL20 are formed so as to form an approximately circular shape in a planar view in which light is incident on the photoelectric conversion units of the four pixels PDPX in an end region AEDG in the arrangement direction.

The phase difference detection pixel group PDXG10 is formed, for example, by extending two pixel units PU211, PU212 arranged adjacent to the normal pixel groups NPXG11, NPXG12, NPXG14 in at least one of a first direction and a second direction perpendicular to the first direction (the first direction, X direction in this embodiment).

The two pixel units PU211 and PU212 are formed as pixel units of the same color (G).

The phase difference detection pixel group PDXG10 is formed in a 2 x 4 matrix with multiple (here, 8) same-color pixels arranged in a matrix in at least one direction (X direction in this example) between a first direction (X direction) and a second direction (Y direction) perpendicular to the first direction.

The phase difference detection pixel group PDXG10 can read out a phase difference detection signal acquired by at least one phase difference detection pixel PDPX in the central region ACTR in the arrangement direction and a signal acquired by a pixel PX in the end region AEDG in the arrangement direction to the floating diffusion FD11 as the same (common) readout node.

The phase difference detection pixel group PDXG10 of this embodiment includes a pair of a first set of phase difference detection pixels PDPX1 and a second set of phase difference detection pixels PDPX2 to which light is incident by the shared microlens CMCL10, and the phase difference detection signal read out from the first set of phase difference detection pixels PDPX1 and the phase difference detection signal read out from the second set of phase difference detection pixels PDPX2 are read into a first floating diffusion FD11 and a second floating diffusion FD12 as different readout nodes.

Furthermore, in the pixel section 20 of this embodiment, a light shielding film SLDF for preventing the incidence of unnecessary light is formed at the boundary between the pixels PX.
In the phase difference detection pixel group PDXG10, a light-shielding film SLDF20 that prevents unnecessary light from entering is formed on at least a portion of the boundary between at least one phase difference detection pixel PDPX in the central region ACTR for acquiring a phase difference detection signal and a detection pixel DPX in the end region AEDG for acquiring a signal, so as to spatially overlap at least a portion of the detection pixel DPX in the end region AEDG.
In other words, on the detection pixel DPX in the end region AEDG, a light-shielding film SLDF20 that prevents the incidence of unnecessary light is formed in approximately half of the area from the boundary in the central region ACTR toward the end, so as to spatially overlap with the individual microlenses PMCL20, etc.

In addition, in this embodiment, in order to suppress color mixing and blooming, the width of the light-shielding film SLDF is made thicker (thicker, wider) than in other regions in at least one of the boundary between the phase difference detection pixel PDPX and the normal pixel NPX and the pixel boundary within the phase difference detection pixel group PDXG10.

Specific configuration examples of the phase difference detection pixel group PDXG10, the configuration of which has been outlined above, will be described later.

As described above, in this embodiment, in the pixel section 20, the normal pixel groups NPXG11, NPXG12, and NPXG14 are four units, namely the first same-color pixel unit PU111, the second same-color pixel unit PU112, the third same-color pixel unit PU113, and the fourth same-color pixel unit, which are arranged in a square such that in the first direction, the first same-color pixel unit PU111 and the second same-color pixel unit PU112 are adjacent to each other, and the third same-color pixel unit PU113 and the fourth same-color pixel unit PU114 are adjacent to each other, and in the second direction perpendicular to the first direction, the first same-color pixel unit PU111 and the third same-color pixel unit PU113 are adjacent to each other, and the second same-color pixel unit PU112 and the fourth same-color pixel unit PU114 are adjacent to each other.
Each of the first same-color pixel unit PU111, the second same-color pixel unit PU112, the third same-color pixel unit PU113, and the fourth same-color pixel unit PU114 has a plurality of same-color normal pixels NPX that form a pixel unit PU arranged in a matrix of q x q (q is a positive integer of 2 or more), and each normal pixel NPX has an individual type microlens PMCL1 that introduces light into the photoelectric conversion unit of the normal pixel NPX.
Alternatively, each of the first same-color pixel unit PU111, the second same-color pixel unit PU112, the third same-color pixel unit PU113, and the fourth same-color pixel unit PU114 may have a plurality of same-color normal pixels NPX that form the pixel unit PU arranged in a q x q matrix (q is a positive integer greater than or equal to 2), and one shared microlens CMCL20 is arranged for every four normal pixels NPX of each pixel unit.

In addition, in this embodiment, the normal pixels NPX that form the first same-color pixel unit PU111 and the fourth same-color pixel unit PU114 of the normal pixel groups NPXG11, NPXG12, and NPXG14, and the phase difference detection pixels PDPX that form the phase difference detection pixel units PU211 and PU212 in the phase difference detection pixel group PDXG10 are formed of pixels of the same color (for example, green (G)).

The vertical scanning circuit 30 drives pixels in the shutter row and the readout row through row scanning control lines under the control of the timing control circuit 60 .
Furthermore, the vertical scanning circuit 30 outputs a row selection signal of the row address of a read row for reading out a signal and a shutter row for resetting the charge accumulated in the photodiode PD in accordance with the address signal.

In normal pixel readout operation, a shutter scan is performed by the vertical scanning circuit 30 of the readout control system, and then a readout scan is performed.

The readout circuit 40 may include multiple column signal processing circuits (not shown) arranged corresponding to each column output of the pixel section 20, and may be configured to enable column parallel processing by the multiple column signal processing circuits.

The readout circuit 40 can be configured to include a correlated double sampling (CDS) circuit, an analog-to-digital converter (ADC), an amplifier (AMP), a sample-and-hold (S/H) circuit, etc.

The horizontal scanning circuit 50 scans the signals processed by multiple column signal processing circuits such as the ADC of the readout circuit 40, transfers them in the horizontal direction, and outputs them to the signal processing circuit.

The timing control circuit 60 generates timing signals necessary for signal processing of the pixel section 20, vertical scanning circuit 30, readout circuit 40, horizontal scanning circuit 50, etc.

In this embodiment, under the control of the read drive control unit 70, the pixel signals of the normal pixels NPX in the normal pixel groups NPXG11, NPXG12, and NPXG14, and the phase difference information from the phase difference detection pixels PDPX in the phase difference detection pixel group PDXG10 are all added together and read out.

The following describes the pixel section 20 of the solid-state imaging device 10, as well as the specific configuration and arrangement of the pixel unit including multiple pixels of the same color (in this example, four pixels of the same color) in the pixel section 20, the normal pixel group, the phase difference detection pixel group, etc., and an overview of the configuration and function of each part.

(Examples of the configuration of the pixel array 200, pixel group PXG, pixel unit PU, and phase difference detection pixel group PDXG10 of the pixel section 20)
FIG. 4 is a diagram showing an example of forming a pixel array in a pixel section according to the first embodiment of the present invention.
FIG. 5 is a diagram illustrating an example of a pixel group that forms a pixel array according to the first embodiment of the present invention.
FIG. 6 is a diagram showing an example of a phase difference detection pixel group that forms a pixel array according to the first embodiment of the present invention.
FIG. 7 is a diagram showing an example of a pixel array of a phase difference detection pixel group according to the first embodiment of the present invention.
FIG. 8 is a simplified cross-sectional view showing an example of a phase difference detection pixel group forming a pixel array according to the first embodiment of the present invention and its adjacent region.
FIG. 9 is a diagram showing an example of an element isolation unit in a phase difference detection pixel group that forms a pixel array according to the first embodiment of the present invention.
FIG. 10 is a circuit diagram showing an example of a pixel unit in which one floating diffusion is shared by four pixels in a pixel group of the solid-state imaging device according to the first embodiment of the present invention.

In this embodiment, the first direction is, for example, a column direction (horizontal direction, X direction), a row direction (vertical direction, Y direction), or a diagonal direction of the pixel unit 20 in which a plurality of pixels are arranged in a matrix.
In the following description, as an example, the first direction is the column direction (horizontal direction, X direction), and the second direction is the row direction (vertical direction, Y direction).

The pixel section 20 is configured by arranging a plurality of pixels PX, each of which includes a photodiode (photoelectric conversion section) and an in-pixel amplifier, in a two-dimensional matrix to form a pixel array 200.

As described above, the pixel section 20 is formed by arranging pixel units (PU) including a plurality of same-color pixels (PX) that perform photoelectric conversion in an array (in the example of FIG. 4, in a matrix shape) as shown in FIG.
In the pixel section 20, pixel groups PXG11, PXG12, PXG13, and PXG14 formed by a plurality (four in this example) of pixel units PU each including a plurality (four in this example) of adjacent same-color pixels PX are arranged in a 2x2 matrix.
More specifically, the pixel section 20 is configured by mixing a normal pixel group NPXG formed by a plurality (four in this example) of pixel units PU including a plurality (four in this example) of adjacent same-color pixels PX, and a phase difference detection pixel group PDXG10 for detecting phase difference information for controlling the focus function.

In the example of Figure 4, as described below, pixel groups PXG11, PXG12, and PXG14 are applied as normal pixel groups NPXG11, NPXG12, and NPXG14, and a portion of pixel group PXG13 is used as phase difference detection pixel group PDXG10.

Each pixel PX basically includes a photodiode and a plurality of pixel transistors, such as a transfer transistor, a reset transistor, a source follower transistor having an amplification function, and a selection transistor.
However, in this first embodiment, as an example, a four-pixel sharing configuration is adopted in which four same-color pixels PX of a pixel unit PU share one floating diffusion FD (Floating Diffusion layer), as shown in Figures 5 and 10.
Specifically, as will be described in detail later, four same-color pixels PX share a floating diffusion FD11, a reset transistor RST11-Tr, a source follower transistor SF11-Tr, and a selection transistor SEL11-Tr.
Furthermore, the shared floating diffusion FD11 functions as an adder of pixel signals read out from a plurality of pixels of the same pixel unit PU that are referenced for correction, for example, when correcting the sensitivity value of an arbitrary pixel.

In the pixel array 200 of the first embodiment, a pixel unit PU is formed by arranging multiple adjacent (four in the first embodiment) same-color pixels PX in a q×q (q is an integer equal to or greater than 2, 2×2 in the first embodiment) square array, and four adjacent pixel units PU form a pixel group PXG, and the pixel array 200 is constituted by arranging multiple pixel groups PXG in a matrix.

In the example of Figure 4, in order to simplify the drawing, a pixel array 200 is shown in which four pixel groups PXG11, PXG12, PXG13, and PXG14 are arranged in a 2 x 2 matrix.

(Configuration of pixel group PXG and pixel unit PU)
4, the pixel group PXG11 has a pixel unit PU111 of G (Gb) pixels, a pixel unit PU112 of B pixels, a pixel unit PU113 of R pixels, and a pixel unit PU114 of G (Gr) pixels arranged in a Bayer array. The pixel group PXG11 is formed as a normal pixel group NPXG11.

The pixel group PXG12 has a pixel unit PU121 of a G (Gb) pixel, a pixel unit PU122 of a B pixel, a pixel unit PU123 of an R pixel, and a pixel unit PU124 of a G (Gr) pixel arranged in a Bayer array. The pixel group PXG12 is normally formed as a pixel group NPXG12.

The pixel group PXG13 includes a pixel unit PU131 of G (Gb) pixels, a pixel unit PU132 of G pixels, a pixel unit PU133 of R pixels, and a pixel unit PU134 of G (Gr) pixels arranged in a Bayer array.
When the pixel group PXG13 is formed as a normal pixel group NPXG13, the pixels of the pixel unit PU132 to which B pixels are applied are formed by G pixels of the same color as the pixel unit PU131 (or pixel unit PU134).
A part of the pixel group PXG13 is used as a phase difference detection pixel group PDXG10.
Specifically, the pixel unit PU131 of the G pixel is used as a pixel unit PU211 for phase difference detection, and the pixel unit PU132 of the G pixel, which is connected so as to extend adjacent to the pixel unit PU131 in the X direction, is used as a pixel unit PU212 for phase difference detection, thereby forming the phase difference detection pixel group PDXG10.

The phase difference detection pixel group PDXG10 is formed to include a greater number (5 or more, 2 x 4 = 8 in this example) of phase difference detection pixels PDPX of the same color (green (G) in this example) than the number (4) of pixels NPX that form the pixel units PU of the normal pixel groups NPXG11, NPXG12, and NPXG14.
As a result, the solid-state imaging device 10 can suppress a decrease in sensitivity of phase difference pixels even in miniaturized pixels, and realizes that it is possible to achieve high phase difference performance with high speed and good focusing performance even in shooting scenes with a low amount of incident light.

The pixel group PXG14 is a Bayer array of pixel units PU141 for G (Gr) pixels, pixel units PU142 for B pixels, pixel units PU143 for R pixels, and pixel units PU144 for G (Gr) pixels. The pixel group PXG14 is formed as a normal pixel group NPXG14.

In addition, in this embodiment, in order to suppress color mixing and blooming, the width of the light-shielding film SLDF is made thicker (wider) than in other regions in at least one of the boundary between the phase difference detection pixel PDPX and the normal pixel NPX and the pixel boundary within the phase difference detection pixel group PDXG10.

(Configuration example of phase difference detection pixel group PDXG10)
Here, a specific configuration example of the phase difference detection pixel group PDXG10 according to the first embodiment will be described.
In the normal pixel groups NPXG11, NPXG12, and NPXG14 of the first embodiment, one individual microlens PMCL1 formed to have a substantially circular shape in a plan view is disposed for each pixel NPX that forms each pixel unit PU.

In contrast, as shown in FIG. 6, the phase difference detection pixel group PDXG10 is arranged with one shared microlens CMCL10 that is arranged so as to form an approximately circular shape in a planar view, in which light is incident on the photoelectric conversion units of four phase difference detection pixels PDPX (hereinafter, sometimes referred to (or written as) PDX) in a central region ACTR in the arrangement direction that forms the phase difference detection pixel group PDXG10.
In addition, in the phase difference detection pixel group PDXG10, four individual microlenses PMCL20 (21 to 24) are formed to form a substantially circular shape in a plan view, which allow light to be incident on the photoelectric conversion units of the four pixels PDPX in the end area AEDG in the arrangement direction.
are placed.

The phase difference detection pixel group PDXG10 is formed, for example, by extending two pixel units PU211, PU212 arranged adjacent to the normal pixel groups NPXG11, NPXG12, NPXG14 in at least one of a first direction and a second direction perpendicular to the first direction (the first direction, X direction in this embodiment).

The two pixel units PU211 and PU212 are formed as pixel units of the same color (G).

8, in each of the pixel units PU211 to PU212, two pixels PX-A to PX-B as pixels of the same color are separated into two by a first element isolation portion ESPL1 in the light incidence portion of the photoelectric conversion region PD(1,2). The first element isolation portion ESPL1 is separated into two by, for example, a backside metal BSM as a backside isolation portion.
In addition, in the photoelectric conversion region PD, a second element isolation portion ESPL2 as a trench-type backside isolation is formed so as to spatially overlap with the first element isolation portion ESPL1 formed by a backside metal BSM or the like in the depth direction of the photoelectric conversion region PD. The second element isolation portion RSPL2 is formed by, for example, backside deep trench isolation (BDTI).
As a result, the same-color pixel PX-A includes a first photoelectric conversion region, and the same-color pixel PX-B includes a second photoelectric conversion region.
Moreover, pixel units of different colors are also isolated by a first element isolation portion ESPL1 (for example, BSM), or by a first element isolation portion ESPL1 (for example, BSM) and a second element isolation portion ESPL2 (for example, BDTI).
In the example of Figure 8, in order to strengthen the light-shielding ability between pixel units of different colors, it is also possible to form the first element isolation portion ESPL1 (e.g., BSM) and the second element isolation portion ESPL2 (e.g., BDTI) so as to have a thicker film thickness for element isolation.

The first element isolation portion ESPL1 formed by the backside metal portion BSM or the like is formed of, for example, gold, aluminum, titanium, copper, chromium, palladium, nickel, silver, tungsten, or the like.

As described above, in this embodiment, in order to suppress color mixing and blooming, the width of the light-shielding film SLDF is made thicker (wider) than in other regions at least in one of the boundaries between the phase difference detection pixels PDPX and normal pixels NPX and the pixel boundaries within the phase difference detection pixel group PDXG10.

As shown in FIG. 6, the phase difference detection pixel group PDXG10 according to the first embodiment has a first light-shielding film SLDF21 formed on the first pixel unit PU211 side and a second light-shielding film SLDF22 formed on the second pixel unit PU212 side.

The phase difference detection pixel group PDXG10 can read out a phase difference detection signal acquired by at least one phase difference detection pixel PDPX in the central region ACTR in the arrangement direction and a signal acquired by a pixel PX in the end region AEDG in the arrangement direction to the floating diffusion FD11 (FD12) as the same (common) readout node.

The phase difference detection pixel group PDXG10 of this first embodiment includes a pair of a first set of phase difference detection pixels PDPX1 and a second set of phase difference detection pixels PDPX2 to which light is incident through the shared microlens CMCL10, and the phase difference detection signal read out from the first set of phase difference detection pixels PDPX1 and the phase difference detection signal read out from the second set of phase difference detection pixels PDPX2 are read into floating diffusions FD11 and FD12 as different readout nodes.

Furthermore, in the pixel section 20 of the first embodiment, light shielding films SLDF21 and SLDF22 for preventing the incidence of unnecessary light are formed at the boundaries between the pixels PX.
In the phase difference detection pixel group PDXG10, at least one phase difference detection pixel PDPX in the central region ACTR for acquiring a phase difference detection signal and at least a portion of the boundary between the detection pixel DPX in the end region AEDG for acquiring a signal, light-shielding films SLDF21, 22 for preventing the incidence of unnecessary light are formed so as to spatially overlap at least a portion of the detection pixel DPX in the end region AEDG.
In other words, on the detection pixel DPX in the end regions AEDG1, 2, light-shielding films SLDF21, SLDF22 that prevent the incidence of unnecessary light are formed in approximately half of the area from the boundaries BDR11, BDR12 in the central region ACTR toward the ends TP1, TP2, so as to spatially overlap with the individual microlenses PMCL20, etc.

Here, we will explain a more specific example configuration of the phase difference detection pixel group PDXG10.

In the phase difference detection pixel group PDXG10, the first pixel unit PU211 has four pixels, a first same-color pixel DPX1, a second same-color pixel DPX2, a third same-color pixel DPX3, and a fourth same-color pixel DPX4, which are arranged in a square shape as shown in FIG. 6, such that the first same-color pixel DPX1 and the second same-color pixel DPX2 are adjacent to each other in the first direction (X direction or second direction (Y direction)), and the third same-color pixel DPX3 and the fourth same-color pixel DPX4 are adjacent to each other in the second direction (or first direction) perpendicular to the first direction (or second direction).

The second pixel unit PU212 has four pixels of the same color: a fifth pixel of the same color DPX5, a sixth pixel of the same color DPX6, a seventh pixel of the same color DPX7, and an eighth pixel of the same color DPX8. The pixels are arranged in a square such that the fifth pixel of the same color DPX5 and the sixth pixel of the same color DPX6 are adjacent to each other in the first direction (or the second direction), and the seventh pixel of the same color DPX7 and the eighth pixel of the same color DPX8 are adjacent to each other in the second direction (or the first direction) perpendicular to the first direction (or the second direction).

The first pixel unit PU211 and the second pixel unit PU212 are arranged in the first direction (or the second direction) such that the second same-color pixel DPX2 and the fifth same-color pixel DPX5 are adjacent to each other, and the fourth same-color pixel DPX4 and the seventh same-color pixel DPX7 are adjacent to each other.

In the phase difference detection pixel group PDXG10, the pixel unit PU213 in the central region ACTR in the arrangement direction is formed by a square arrangement of four pixels: the second same-color pixel DPX2 and the fourth same-color pixel DPX4 of the first pixel unit PU211, and the fifth same-color pixel DPX5 and the seventh same-color pixel DPX7 of the second pixel unit PU212.

The phase difference detection pixel group PDXG10 has a first sharing structure CMN1 in which four pixels in the first pixel unit PU211, namely a first same-color pixel DPX1, a second same-color pixel DPX2, a third same-color pixel DPX3, and a fourth same-color pixel DPX4, share a first floating diffusion FD11 as a first readout node.
The phase difference detection pixel group PDXG10 has a second sharing structure CMN2 in which four pixels in the second pixel unit PU212, namely, the fifth same-color pixel DPX5, the sixth same-color pixel DPX6, the seventh same-color pixel DPX7, and the eighth same-color pixel DPX8, share a second floating diffusion FD12 as a second readout node.

In the pixel unit PU213 of the central region ACTR, the phase difference detection pixel group PDXG10 is arranged such that one shared microlens CMCL10 causes light to be incident on the photoelectric conversion unit PD2 of the second same-color pixel DPX of the first pixel unit PU211, the photoelectric conversion unit PD4 of the fourth same-color pixel DPX4, the photoelectric conversion unit PD5 of the fifth same-color pixel DPX5 of the second pixel unit PU212, and the photoelectric conversion unit PD7 of the seventh same-color pixel DPX7.

Furthermore, in the phase difference detection pixel group PDXG10, the first individual microlens PMCL21 is arranged so as to make light incident on the photoelectric conversion unit PD1 of the first same-color pixel DPX1 of the first pixel unit PU211.
The second individual microlens PMCL22 is disposed so as to make light incident on the photoelectric conversion unit PD3 of the third same-color pixel DPX3 of the first pixel unit PU211.
The third individual type microlens PMCL23 is disposed so as to make light incident on the photoelectric conversion unit PD6 of the sixth same-color pixel DPX6 of the second pixel unit PU212.
The fourth individual type microlens PMCL24 is disposed so as to make light incident on the photoelectric conversion unit PD8 of the eighth same-color pixel DPX8 of the second pixel unit PU212.

In addition, in the phase difference detection pixel group PDXG10, a first light-shielding film SLDF1 that prevents the incidence of unnecessary light is formed from a first boundary portion BDR1 between the first same-color pixel DPX1 and the third same-color pixel DPX3 of the first pixel unit PU211 that forms the first end region AEDG1 and the second same-color pixel DPX2 and the fourth same-color pixel DPX4 of the pixel unit PU213 in the central region ACTR toward the first end region AEDG1 so as to spatially overlap at least a portion of the first individual type microlens PMCL21 and the second individual type microlens PMCL22.

In this first embodiment, a first light-shielding film SLDF21 that prevents the incidence of unnecessary light is formed so as to spatially overlap approximately half of the area of the first individual type microlens PMCL21 and the second individual type microlens PMCL22 from the first boundary portion BDR1 toward the first end region AEDG1.

Furthermore, in the phase difference detection pixel group PDXG10, a second light-shielding film SLDF22 that prevents the incidence of unnecessary light is formed from the second boundary portion BDR2 between the sixth same-color pixel DPX6 and the eighth same-color pixel DPX8 of the second pixel unit PU212 that forms the second end region AEDG2 and the fifth same-color pixel DPX5 and the seventh same-color pixel DPX7 of the pixel unit PU213 in the central region ACTR toward the second end in the opposite direction to the first end, so as to spatially overlap at least a portion of the third individual type microlens PMCL23 and the fourth individual type microlens PMCL24.

In this first embodiment, a second light-shielding film SLDF2 that prevents the incidence of unnecessary light is formed so as to spatially overlap approximately half of the area of the third individual type microlens PMCL23 and the fourth individual type microlens PMCL24 from the second boundary portion BDR2 toward the second end region AEDG2.

As shown in Figures 7 and 9, in the pixel unit PU213 of the central region ACTR, the phase difference detection pixel group PDXG10 has element isolation sections 220 (221 to 224) formed of BSM or BSM and BDTI, etc. between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD4 of the fourth same-color pixel DPX4, between the photoelectric conversion section PD5 of the fifth same-color pixel DPX5 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7, between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD5 of the fifth same-color pixel DPX5, and between the photoelectric conversion section PD4 of the fourth same-color pixel DPX4 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7.

As described above, in the first embodiment, as shown in FIG. 10, a four-pixel sharing configuration in which four pixels of the same color in a pixel unit share one floating diffusion FD may be adopted.
Here, a description will be given of an example of a four-pixel sharing configuration in which one floating diffusion FD is shared by four pixels of the same color in a pixel unit.

(Example of a configuration in which four pixels are shared in a pixel unit)
FIG. 10 shows an example of a circuit system of a pixel unit in which one floating diffusion is shared by four pixels of a pixel group of the solid-state imaging device according to the first embodiment of the present invention.

In the pixel section 20 of FIG. 10, the pixel unit PU of the pixel group PXG has four pixels (color pixels in this embodiment, G pixels here), namely, a first color pixel PX11, a second color pixel PX12, a third color pixel PX13, and a fourth color pixel PX14, arranged in a 2×2 square.

The first color pixel PX11 includes a photodiode PD11 formed by the first photoelectric conversion region, and a transfer transistor TG11-Tr.

The second color pixel PX12 includes a photodiode PD12 formed by the second photoelectric conversion region, and a transfer transistor TG12-Tr.

The third color pixel PX13 includes a photodiode PD13 formed by a third photoelectric conversion region, and a transfer transistor TG13-Tr.

The fourth color pixel PX14 includes a photodiode PD14 formed by a fourth photoelectric conversion region, and a transfer transistor TG14-Tr.

The pixel unit PU that forms the pixel group PXG has four color pixels PX11, PX12, PX13, and PX14, which share the floating diffusion FD11, reset transistor RST11-Tr, source follower transistor SF11-Tr, and selection transistor SEL11-Tr.

In such a four-pixel sharing configuration, for example, the first color pixel PX11, the second color pixel PX12, the third color pixel PX13, and the fourth color pixel PX14 are formed as pixels of the same color, for example, G (Gr, Gb (green)).
For example, the photodiode PD11 of the first color pixel PX11 functions as a first green (G) photoelectric conversion unit, the photodiode PD12 of the second color pixel PX12 functions as a second green (G) photoelectric conversion unit, the photodiode PD13 of the third color pixel PX13 functions as a third green (G) photoelectric conversion unit, and the photodiode PD14 of the fourth color pixel PX14 functions as a fourth green (G) photoelectric conversion unit.

As the photodiodes PD11, PD12, PD13, and PD14, for example, buried photodiodes (PPDs) are used.
Since the surface of the substrate on which the photodiodes PD11, PD12, PD13, and PD14 are formed has a surface state due to defects such as dangling bonds, a large amount of charge (dark current) is generated by thermal energy, making it impossible to read out a correct signal.
In a buried photodiode (PPD), the charge storage portion of the photodiode PD is embedded in a substrate, making it possible to reduce the inclusion of dark current in a signal.

The photodiodes PD11, PD12, PD13, and PD14 generate and accumulate signal charges (electrons in this case) in amounts corresponding to the amount of incident light.
In the following, a case will be described in which the signal charges are electrons and each transistor is an n-type transistor, but the signal charges may be holes and each transistor may be a p-type transistor.

The transfer transistor TG11-Tr is connected between the photodiode PD11 and the floating diffusion FD11, and its conduction state is controlled by a control signal TG11.
Under the control of the readout control system, the transfer transistor TG11-Tr is selected and turned on during the period when the control signal TG11 is at a predetermined high level (H), and transfers the charge (electrons) photoelectrically converted and accumulated in the photodiode PD11 to the floating diffusion FD11.

The transfer transistor TG12-Tr is connected between the photodiode PD12 and the floating diffusion FD11, and its conduction state is controlled by a control signal TG12.
Under the control of the readout control system, the transfer transistor TG12-Tr is selected and becomes conductive during the period when the control signal TG12 is at a predetermined high level (H), and transfers the charge (electrons) photoelectrically converted and accumulated in the photodiode PD12 to the floating diffusion FD11.

The transfer transistor TG13-Tr is connected between the photodiode PD13 and the floating diffusion FD11, and its conduction state is controlled by a control signal TG13.
Under the control of the readout control system, the transfer transistor TG13-Tr is selected and becomes conductive during the period when the control signal TG13 is at a predetermined high level (H), and transfers the charge (electrons) photoelectrically converted and accumulated in the photodiode PD13 to the floating diffusion FD11.

The transfer transistor TG14-Tr is connected between the photodiode PD14 and the floating diffusion FD11, and its conduction state is controlled by a control signal TG14.
Under the control of the readout control system, the transfer transistor TG14-Tr is selected and becomes conductive during the period when the control signal TG14 is at a predetermined high level (H), and transfers the charge (electrons) photoelectrically converted and accumulated in the photodiode PD14 to the floating diffusion FD11.

As shown in FIG. 10, the reset transistor RST11-Tr is connected between the power supply line VDD (or power supply potential) and the floating diffusion FD11, and its conduction state is controlled by a control signal RST11.
Under the control of the read control system, for example, during a read scan, the reset transistor RST11-Tr is selected and turned on while the control signal RST11 is at H level, and resets the floating diffusion FD11 to the potential of the power supply line VDD (or VRst).

The source follower transistor SF11-Tr and the selection transistor SEL11-Tr are connected in series between the power supply line VDD and the vertical signal line LSGN.
A floating diffusion FD11 is connected to the gate of the source follower transistor SF11-Tr, and the conductive state of the selection transistor SEL11-Tr is controlled by a control signal SEL11.
The selection transistor SEL11-Tr is selected and turned on during a period when the control signal SEL11 is at H level, and the source follower transistor SF11-Tr outputs a column output readout voltage (signal) VSL (PIXOUT) obtained by converting the charge of the floating diffusion FD11 into a voltage signal with a gain according to the charge amount (potential) to the vertical signal line LSGN.

In this configuration, when the transfer transistors TG11-Tr, TG12-Tr, TG13-Tr, and TG14-Tr of each pixel PX11, PX12, PX13, and PX14 of the pixel unit PU are turned on and off individually, and the charges photoelectrically converted and stored in the photodiodes PD11, PD12, PD13, and PD14 are sequentially transferred to the common floating diffusion FD11, the pixel signal VSL of the pixel unit is sent to the vertical signal line LSGN and input to the column readout circuit 40.

On the other hand, when multiple transfer transistors TG11-Tr, TG12-Tr, TG13-Tr, and TG14-Tr of each pixel PX11, PX12, PX13, and PX14 are turned on and off simultaneously, and the charges photoelectrically converted and accumulated in the photodiodes PD11, PD12, PD13, and PD14 are transferred simultaneously in parallel to the common floating diffusion FD11, the floating diffusion FD11 functions as an adder.
In this case, a signal obtained by adding together pixel signals from a plurality of pixels in the pixel unit PU, that is, two, three, or four pixels, is sent to a vertical signal line LSGN and input to the column readout circuit 40 .

As described above, in the first embodiment, the pixel section 20 is formed by arranging a plurality of pixels PX, each including a photoelectric conversion section (PD), in an array.
In the pixel section 20, pixel groups PXG11, PXG112, PXG13, and PXG14 formed by a plurality (four in this example) of pixel units PU including a plurality (four in this example) of adjacent same-color pixels PX are arranged in a 2 x 2 matrix. In the pixel section 20 of the first embodiment, a normal pixel group NPXG formed by a plurality (four in this example) of pixel units PU including a plurality (four in this example) of adjacent same-color pixels PX and a phase difference detection pixel group PDXG for detecting phase difference information for controlling the focus function are mixed, and the pixel groups PXG11, PXG12, and PXG14 are used as the normal pixel groups NPXG11, NPXG12, and NPXG14, and a part of the pixel group PXG13 is used as the phase difference detection pixel group PDXG10.
The phase difference detection pixel group PDXG10 is formed to include a greater number (5 or more, 2 x 4 = 8 in this example) of phase difference detection pixels PDPX of the same color (green (G) in this example) than the number (4) of pixels NPX that form the pixel units PU of the normal pixel groups NPXG11, NPXG12, and NPXG14.

Furthermore, in the normal pixel groups NPXG11, NPXG12, and NPXG14 of this first embodiment, one individual microlens CMCL1 formed to form an approximately circular shape in a planar view is arranged for each pixel NPX that forms each pixel unit PU.
In contrast, the phase difference detection pixel group PDXG10 is arranged with one shared microlens CMCL10 formed so as to form an approximately circular shape in a planar view that causes light to be incident on the photoelectric conversion units of the four phase difference detection pixels PDPX in a central region ACTR in the arrangement direction that forms the phase difference detection pixel group, and four individual microlenses PMCL20 formed so as to form an approximately circular shape in a planar view that causes light to be incident on the photoelectric conversion units of the four pixels PDPX in an end region AEDG in the arrangement direction.
The phase difference detection pixel group PDXG10 is formed, for example, by extending two pixel units PU211, PU212 of the same color (G) that are arranged adjacent to the normal pixel groups NPXG11, NPXG12, and NPXG14 in a first direction (X direction).

The phase difference detection pixel group PDXG10 can read out a phase difference detection signal acquired by at least one phase difference detection pixel PDPX in the central region ACTR in the arrangement direction and a signal acquired by a pixel PX in the end region AEDG in the arrangement direction to the floating diffusion FD11 (FD12) as the same (common) readout node.

Therefore, according to the first embodiment, it is possible to suppress the decrease in sensitivity of the phase difference pixels even in miniaturized pixels, and it is possible to achieve high phase difference performance with high speed and good focusing performance even in shooting scenes with a low amount of incident light.

Furthermore, according to this first embodiment, the phase difference detection pixel group PDXG10 includes a pair of a first set of phase difference detection pixels PDPX1 and a second set of phase difference detection pixels PDPX2 to which light is incident by the shared microlens CMCL10, and the phase difference detection signal read out from the first set of phase difference detection pixels PDPX1 and the phase difference detection signal read out from the second set of phase difference detection pixels PDPX2 are read into floating diffusions FD11 and FD12 as different readout nodes.

Therefore, according to the first embodiment, in an area including phase difference detection pixels, signals of two or more colors can be read out to the same floating diffusion FD, and as a result, pixel signals of the same color can be read out to the same readout node in the phase difference detection pixel group with high image quality and without reducing the frame rate.

In addition, according to the first embodiment, the light-shielding film width is made thicker (wider) in at least one of the boundaries between phase difference detection pixels and normal pixels and the pixel boundaries within the phase difference detection pixel group PDXG10 than in other regions, making it possible to efficiently suppress color mixing and blooming.

Furthermore, according to the first embodiment, it is possible to simultaneously achieve better low-light PDAF (phase detection autofocus) performance and better light blocking performance, which in turn makes it possible to achieve more accurate image quality.

As described above, according to the first embodiment, it is possible to suppress the decrease in sensitivity of phase difference detection pixels even in miniaturized pixels, and it is possible to achieve high phase difference performance with high speed and good focusing performance even in shooting scenes with a low amount of incident light, and it is also possible to read out pixel signals of the same color to the same readout node in a group of phase difference detection pixels with high image quality and without reducing the frame rate.

Second Embodiment
FIG. 11 is a diagram showing an example of formation of a phase difference detection pixel group in a pixel array of a pixel section according to the second embodiment of the present invention.
FIG. 12 is a simplified cross-sectional view showing an example of a phase difference detection pixel group and its adjacent region that form a pixel array according to the second embodiment of the present invention.
FIG. 13 is a diagram showing an example of formation of an element isolation portion in a phase difference detection pixel group that forms a pixel array according to the second embodiment of the present invention.

The pixel unit 20A of this second embodiment differs from the pixel unit 20 of the first embodiment described above in the following ways.

In the phase difference detection pixel group PDXG10 of the first embodiment, in the pixel unit PU213 of the central region ACTR, one shared microlens CMCL10 formed to have an approximately circular shape in a planar view is arranged so that light is incident on the photoelectric conversion unit PD2 of the second same-color pixel DPX of the first pixel unit PU211, the photoelectric conversion unit PD4 of the fourth same-color pixel DPX4, the photoelectric conversion unit PD5 of the fifth same-color pixel DPX5 of the second pixel unit PU212, and the photoelectric conversion unit PD7 of the seventh same-color pixel DPX7.

In contrast, the phase difference detection pixel group PDXG10A of the second embodiment employs two shared microlenses CMCL11 and CMCL12 formed to have an oval (elliptical) shape in plan view in the pixel unit PU213 of the central region ACTR.

In the phase difference detection pixel group PDXG10A of this second embodiment, in the pixel unit PU213 of the central region ACTR, the first shared microlens CMCL11 is arranged so that light is incident on the photoelectric conversion unit PD2 of the second same-color pixel DPX2 of the first pixel unit PU211 and the photoelectric conversion unit PD5 of the fifth same-color pixel DPX5 of the second pixel unit PU212.
Similarly, in the pixel unit PU213 in the central region ACTR, the second shared microlens CMCL12 is arranged so as to direct light to the photoelectric conversion unit PD4 of the fourth same-color pixel DPX4 of the first pixel unit PU211 and the photoelectric conversion unit PD7 of the seventh same-color pixel DPX7 of the second pixel unit PU212.

The element isolation section 220A in the phase difference detection pixel group PDXG10A according to the second embodiment is formed in the same manner as in the phase difference detection pixel group PDXG10 according to the first embodiment described above.

That is, as shown in FIG. 13, in the phase difference detection pixel group PDXG10A, in the pixel unit PU213 in the central region ACTR, element isolation sections 220A (221-224) formed of BSM or BSM and BDTI, etc. are formed between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD4 of the fourth same-color pixel DPX4, between the photoelectric conversion section PD5 of the fifth same-color pixel DPX5 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7, between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD5 of the fifth same-color pixel DPX5, and between the photoelectric conversion section PD4 of the fourth same-color pixel DPX4 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7.

According to the second embodiment, it is possible to obtain the same effects as those of the first embodiment described above.
That is, according to the second embodiment, it is possible to suppress a decrease in sensitivity of the phase difference detection pixels even in miniaturized pixels, and it is possible to realize high phase difference performance with high speed and good focusing performance even in shooting scenes with a low amount of incident light, and it is also possible to read out pixel signals of the same color to the same readout node in a phase difference detection pixel group with high image quality and without reducing the frame rate.

Furthermore, according to the second embodiment, the light-shielding film width is formed thicker (wider) than in other regions in at least one of the boundary between the phase difference detection pixel and the normal pixel and the pixel boundary within the phase difference detection pixel group PDXG10, so that it is possible to efficiently suppress color mixing and blooming.
Furthermore, according to the second embodiment, it is possible to simultaneously achieve better low-illumination PDAF (phase detection autofocus) performance and better light blocking performance, thereby making it possible to achieve more accurate image quality.

Third Embodiment
FIG. 14 is a diagram showing an example of formation of an element isolation portion in a phase difference detection pixel group that forms a pixel array according to the third embodiment of the present invention.

The pixel unit 20B of this third embodiment differs from the pixel unit 20 of the first embodiment described above in the following ways.

In the phase difference detection pixel group PDXG10 of the first embodiment, in the pixel unit PU213 of the central region ACTR, element isolation sections 220 (221 to 224) formed of BSM or BSM and BDTI, etc. are formed between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD4 of the fourth same-color pixel DPX4, between the photoelectric conversion section PD5 of the fifth same-color pixel DPX5 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7, between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD5 of the fifth same-color pixel DPX5, and between the photoelectric conversion section PD4 of the fourth same-color pixel DPX4 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7.

In contrast to this, in the phase difference detection pixel group PDXG10B of the third embodiment, in the pixel unit PU213 of the central region ACTR, element isolation sections (221, 222) are not selectively formed between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD4 of the fourth same-color pixel DPX4, and between the photoelectric conversion section PD5 of the fifth same-color pixel DPX5 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7, and element isolation sections 220B (223, 224) composed of BSM, or BSM and BDTI, etc. are selectively formed between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD5 of the fifth same-color pixel DPX5, and between the photoelectric conversion section PD4 of the fourth same-color pixel DPX4 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7.

According to the third embodiment, it is possible to obtain the same effect as the first embodiment described above, and also to suppress unnecessary radiation to other regions, thereby reducing crosstalk between pixels.

Fourth Embodiment
FIG. 15 is a diagram showing an example of formation of an element isolation portion in a phase difference detection pixel group that forms a pixel array according to the fourth embodiment of the present invention.

The pixel unit 20C of this fourth embodiment differs from the pixel unit 20 of the first embodiment described above in the following ways.

In the phase difference detection pixel group PDXG10 of the first embodiment, in the pixel unit PU213 of the central region ACTR, element isolation sections 220A (221 to 224) formed of BSM or BSM and BDTI, etc. are formed between the photoelectric conversion unit PD2 of the second same-color pixel DPX2 and the photoelectric conversion unit PD4 of the fourth same-color pixel DPX4, between the photoelectric conversion unit PD5 of the fifth same-color pixel DPX5 and the photoelectric conversion unit PD7 of the seventh same-color pixel DPX7, between the photoelectric conversion unit PD2 of the second same-color pixel DPX2 and the photoelectric conversion unit PD5 of the fifth same-color pixel DPX5, and between the photoelectric conversion unit PD4 of the fourth same-color pixel DPX4 and the photoelectric conversion unit PD7 of the seventh same-color pixel DPX7.

In contrast, in the phase difference detection pixel group PDXG10C of the fourth embodiment, in the pixel unit PU213 of the central region ACTR, the element isolation section 220C (223, 224) is not selectively formed between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD4 of the fourth same-color pixel DPX4, and between the photoelectric conversion section PD5 of the fifth same-color pixel DPX5 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7, and the element isolation section 220C (221, 222) composed of BSM, or BSM and BDTI, etc. is not selectively formed between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD5 of the fifth same-color pixel DPX5, and between the photoelectric conversion section PD4 of the fourth same-color pixel DPX4 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7.

According to the fourth embodiment, it is possible to obtain the same effect as the first embodiment described above, and also to suppress unnecessary radiation to other regions, thereby reducing crosstalk between pixels.

Fifth Embodiment
FIG. 16 is a diagram showing an example of formation of an element isolation portion in a phase difference detection pixel group that forms a pixel array according to the fifth embodiment of the present invention.

The pixel unit 20D of this fifth embodiment differs from the pixel unit 20A of the second embodiment described above in the following ways:

In the phase difference detection pixel group PDXG10A of the second embodiment, in the pixel unit PU213 of the central region ACTR, element isolation sections 220A (221 to 224) formed of BSM or BSM and BDTI, etc. are formed between the photoelectric conversion unit PD2 of the second same-color pixel DPX2 and the photoelectric conversion unit PD4 of the fourth same-color pixel DPX4, between the photoelectric conversion unit PD5 of the fifth same-color pixel DPX5 and the photoelectric conversion unit PD7 of the seventh same-color pixel DPX7, between the photoelectric conversion unit PD2 of the second same-color pixel DPX2 and the photoelectric conversion unit PD5 of the fifth same-color pixel DPX5, and between the photoelectric conversion unit PD4 of the fourth same-color pixel DPX4 and the photoelectric conversion unit PD7 of the seventh same-color pixel DPX7.

In contrast, in the phase difference detection pixel group PDXG10D of the fifth embodiment, in the pixel unit PU213 of the central region ACTR, element isolation sections (223, 224) are selectively formed between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD4 of the fourth same-color pixel DPX4, and between the photoelectric conversion section PD5 of the fifth same-color pixel DPX5 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7, and element isolation sections 220D (221, 222) composed of BSM, or BSM and BDTI, etc. are not selectively formed between the photoelectric conversion section PD2 of the second same-color pixel DPX2 and the photoelectric conversion section PD5 of the fifth same-color pixel DPX5, and between the photoelectric conversion section PD4 of the fourth same-color pixel DPX4 and the photoelectric conversion section PD7 of the seventh same-color pixel DPX7.

According to the fifth embodiment, it is possible to obtain the same effect as the second embodiment described above, and also to suppress unnecessary radiation to other regions, thereby reducing crosstalk between pixels.

The solid-state imaging devices 10, 10A to 10D described above can be used as imaging devices in electronic devices such as digital cameras, video cameras, mobile terminals, surveillance cameras, and medical endoscope cameras.

Figure 17 is a diagram showing an example of the configuration of an electronic device equipped with a camera system to which a solid-state imaging device according to an embodiment of the present invention is applied.

As shown in FIG. 17, the electronic device 800 has a CMOS image sensor 810 to which the solid-state imaging devices 10 and 10A to 10D according to the present embodiment can be applied.
Furthermore, the electronic device 800 has an optical system (lens or the like) 820 that guides incident light to the pixel region of the CMOS image sensor 810 (forming an image of a subject).
The electronic device 800 has a signal processing circuit (PRC) 830 that processes an output signal from the CMOS image sensor 810 .

The signal processing circuit 830 performs predetermined signal processing on the output signal of the CMOS image sensor 810 .
The image signal processed by the signal processing circuit 830 can be displayed as a moving image on a monitor such as an LCD display, or output to a printer. It can also be recorded directly on a recording medium such as a memory card, and various other forms are possible.

As described above, by mounting the above-described solid-state imaging device 10, 10A to 10D as the CMOS image sensor 810, it is possible to provide a high-performance, small-sized, low-cost camera system.
This makes it possible to realize electronic devices such as surveillance cameras and medical endoscope cameras that are used in applications where the camera installation requirements include constraints such as mounting size, number of connectable cables, cable length, and installation height.

10, 10A to 10D... solid-state imaging device, 20, 20A to 20D... pixel unit, 200, 200A to 200D... pixel array, PX... pixel, PDPX, DPX... phase difference detection pixel, PXG... pixel group, NPXG... normal pixel group, PDXG... phase difference detection pixel group, PU... pixel unit, CMCL20, CMCL21, CMCL22... shared type microlens, PMCL20, PMCL21, PMCL22... individual type microlens, SLDF, SLDF21, 2 SLDF21, SLDF22: light shielding film, FD, FD11, FD12: floating diffusion (readout node), 30: vertical scanning circuit, 40: readout circuit, 50: horizontal scanning circuit, 60: timing control circuit, 70: readout drive control unit, 800: electronic device, 810: CMOS image sensor, 820: optical system, 830: signal processing circuit (PRC).

Claims (20)

A pixel unit in which a plurality of pixels, each including a photoelectric conversion unit, are arranged in an array,
In the pixel portion,
A normal pixel group formed by a plurality of pixel units including a plurality of adjacent pixels of the same color;
a phase difference detection pixel group formed to include a greater number of phase difference detection pixels of the same color than the number of pixels forming the pixel unit of the normal pixel group, and for detecting phase difference information for controlling a focusing function;
The phase difference detection pixel group includes:
a plurality of same-color pixels are formed in a matrix shape so as to extend in at least one of a first direction and a second direction perpendicular to the first direction;
At least one shared microlens that causes light to enter a photoelectric conversion unit of at least two of the phase difference detection pixels in a central region in an arrangement direction,
a phase difference detection signal acquired by at least one phase difference detection pixel in the central region and a signal acquired by a pixel in an end region in the arrangement direction can be read out to the same readout node. In the phase difference detection pixel group,
A pair of a first set of phase difference detection pixels and a second set of phase difference detection pixels to which light from the shared microlens is incident,
The solid-state imaging device according to claim 1 , wherein the phase difference detection signals read out from the first set of phase difference detection pixels and the phase difference detection signals read out from the second set of phase difference detection pixels are read into different read nodes. The phase difference detection pixel group includes
The solid-state imaging device according to claim 2 , further comprising: a plurality of individual microlenses for each of a plurality of phase difference detection pixels in an end region in the arrangement direction, the individual microlenses making light incident on a photoelectric conversion unit of the phase difference detection pixel. The pixel is
a photoelectric conversion element as the photoelectric conversion unit that accumulates charges generated by photoelectric conversion during an accumulation period;
a transfer element capable of transferring the charge accumulated in the photoelectric conversion element during a transfer period following the accumulation period;
a floating diffusion as the readout node to which the charge accumulated in the photoelectric conversion element is transferred through the transfer element;
In the phase difference detection pixel group,
The solid-state imaging device according to claim 3 , wherein at least one phase difference detection pixel in the central region for acquiring the phase difference detection signal and a phase difference detection pixel in the end region for acquiring the signal have a shared structure in which the floating diffusion is shared. In the pixel portion,
A light-shielding film is formed at the boundary between the pixels to prevent unnecessary light from entering the boundary.
In the phase difference detection pixel group,
5. The solid-state imaging device according to claim 4, wherein a light-shielding film for preventing incidence of unnecessary light is formed in at least a portion of a boundary between at least one phase difference detection pixel in the central region for acquiring the phase difference detection signal and a phase difference detection pixel in the end region for acquiring the signal, so as to spatially overlap at least a portion of the phase difference detection pixel in the end region. 6. The solid-state imaging device according to claim 5, wherein the light-shielding film is formed to have a thickness greater than that of the light-shielding film in other inter-pixel regions at least in a boundary between the phase difference detection pixel and a normal pixel and a pixel boundary within the phase difference detection pixel group. The phase difference detection pixel group includes
6. The solid-state imaging device according to claim 5, wherein two first pixel units and a second pixel unit arranged adjacent to the normal pixel group are formed so as to extend in at least one of a first direction and a second direction perpendicular to the first direction. In the phase difference detection pixel group,
The first pixel unit includes:
Four pixels, namely, a first pixel of the same color, a second pixel of the same color, a third pixel of the same color, and a fourth pixel of the same color, are
the first same-color pixel and the second same-color pixel are adjacent to each other in a first direction or a second direction, and the third same-color pixel and the fourth same-color pixel are adjacent to each other in a first direction or a second direction;
the first same-color pixel and the third same-color pixel are adjacent to each other in a second direction or the first direction perpendicular to the first direction or the second direction, and the second same-color pixel and the fourth same-color pixel are adjacent to each other in a square array;
The second pixel unit includes:
Four pixels, namely, a fifth pixel of the same color, a sixth pixel of the same color, a seventh pixel of the same color, and an eighth pixel of the same color, are
the fifth pixel of the same color and the sixth pixel of the same color are adjacent to each other in a first direction or a second direction, and the seventh pixel of the same color and the eighth pixel of the same color are adjacent to each other in a first direction or a second direction;
the fifth pixel of the same color and the seventh pixel of the same color are adjacent to each other in a second direction or the first direction perpendicular to the first direction or the second direction, and the sixth pixel of the same color and the eighth pixel of the same color are adjacent to each other in a square array;
The first pixel unit and the second pixel unit include:
the second same-color pixel and the fifth same-color pixel are adjacent to each other in a first direction or a second direction, and the fourth same-color pixel and the seventh same-color pixel are adjacent to each other in a first direction or a second direction;
The pixel unit in the central region is
8. The solid-state imaging device according to claim 7, wherein the second same-color pixel, the fourth same-color pixel of the first pixel unit, and the fifth same-color pixel and the seventh same-color pixel of the second pixel unit are arranged in a square. The phase difference detection pixel group includes
a first sharing structure in which four pixels, namely a first pixel of the same color, a second pixel of the same color, a third pixel of the same color, and a fourth pixel of the same color in the first pixel unit, share a first floating diffusion as a first readout node;
and a second sharing structure in which four pixels of the second pixel unit, namely a fifth pixel of the same color, a sixth pixel of the same color, a seventh pixel of the same color, and an eighth pixel of the same color, share a second floating diffusion as a second readout node. In the pixel unit of the central region,
One of the shared microlenses is
10. The solid-state imaging device of claim 9, wherein light is arranged to be incident on the photoelectric conversion unit of the second same-color pixel of the first pixel unit, the photoelectric conversion unit of the fourth same-color pixel, the photoelectric conversion unit of the fifth same-color pixel of the second pixel unit, and the photoelectric conversion unit of the seventh same-color pixel. In the pixel unit of the central region,
11. The solid-state imaging device of claim 10, wherein element isolation sections are formed between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fourth same-color pixel, between the photoelectric conversion section of the fifth same-color pixel and the photoelectric conversion section of the seventh same-color pixel, between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fifth same-color pixel, and between the photoelectric conversion section of the fourth same-color pixel and the photoelectric conversion section of the seventh same-color pixel. In the pixel unit of the central region,
11. The solid-state imaging device of claim 10, wherein no element isolation section is formed between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fourth same-color pixel, and between the photoelectric conversion section of the fifth same-color pixel and the photoelectric conversion section of the seventh same-color pixel, and element isolation sections are formed between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fifth same-color pixel, and between the photoelectric conversion section of the fourth same-color pixel and the photoelectric conversion section of the seventh same-color pixel. In the pixel unit of the central region,
11. The solid-state imaging device of claim 10, wherein no element isolation section is formed between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fourth same-color pixel, between the photoelectric conversion section of the fifth same-color pixel and the photoelectric conversion section of the seventh same-color pixel, and no element isolation section is formed between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fifth same-color pixel, and between the photoelectric conversion section of the fourth same-color pixel and the photoelectric conversion section of the seventh same-color pixel. In the pixel unit of the central region,
A first shared microlens,
a photoelectric conversion unit of the second same-color pixel of the first pixel unit and a photoelectric conversion unit of the fifth same-color pixel of the second pixel unit are arranged so that light is incident thereon;
A second shared microlens:
The solid-state imaging device according to claim 9 , wherein light is arranged to be incident on a photoelectric conversion unit of the fourth same-color pixel of the first pixel unit and a photoelectric conversion unit of the seventh same-color pixel of the second pixel unit. In the pixel unit of the central region,
15. The solid-state imaging device of claim 14, wherein element isolation sections are formed between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fourth same-color pixel, between the photoelectric conversion section of the fifth same-color pixel and the photoelectric conversion section of the seventh same-color pixel, between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fifth same-color pixel, and between the photoelectric conversion section of the fourth same-color pixel and the photoelectric conversion section of the seventh same-color pixel. In the pixel unit of the central region,
15. The solid-state imaging device of claim 14, wherein element isolation sections are formed between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fourth same-color pixel, and between the photoelectric conversion section of the fifth same-color pixel and the photoelectric conversion section of the seventh same-color pixel, and no element isolation sections are formed between the photoelectric conversion section of the second same-color pixel and the photoelectric conversion section of the fifth same-color pixel, and between the photoelectric conversion section of the fourth same-color pixel and the photoelectric conversion section of the seventh same-color pixel. In the phase difference detection pixel group,
A first discrete microlens:
a first pixel unit having a first same-color pixel and a second pixel unit having a first same-color pixel;
A second discrete microlens:
a first pixel unit having a first same-color pixel and a second same-color pixel unit;
a third discrete microlens;
a sixth same-color pixel of the second pixel unit;
a fourth discrete microlens;
The solid-state imaging device according to claim 8 , wherein the second pixel unit is disposed so that light is incident on a photoelectric conversion unit of the eighth same-color pixel of the second pixel unit. In the phase difference detection pixel group ,
a first light-shielding film for preventing incidence of unnecessary light is formed from a first boundary between the first same-color pixel and the third same-color pixel of the first pixel unit forming a first end region and the second same-color pixel and the fourth same-color pixel of the pixel unit in the central region toward the first end region so as to spatially overlap at least a part of the first individual microlens and the second individual microlens ;
18. The solid-state imaging device of claim 17, wherein a second light-shielding film for preventing the incidence of unnecessary light is formed so as to spatially overlap at least a portion of the third individual microlens and the fourth individual microlens from a second boundary between the sixth same-color pixel and the eighth same-color pixel of the second pixel unit forming a second end region and the fifth same-color pixel and the seventh same-color pixel of the pixel unit in the central region toward a second end in the opposite direction to the first end. A pixel unit in which a plurality of pixels, each including a photoelectric conversion unit, are arranged in an array,
In the pixel portion,
A normal pixel group formed by a plurality of pixel units including a plurality of adjacent pixels of the same color;
a phase difference detection pixel group formed including a greater number of phase difference detection pixels of the same color than a number of pixels forming the pixel unit of the normal pixel group, the phase difference detection pixel group being for detecting phase difference information for controlling a focusing function,
In the step of forming the phase difference detection pixel group,
A plurality of same-color pixels are formed in a matrix shape so as to extend in at least one of a first direction and a second direction perpendicular to the first direction;
forming at least one shared microlens that allows light to be incident on a photoelectric conversion unit of at least two of the phase difference detection pixels in a central region in the arrangement direction;
a phase difference detection signal acquired by at least one phase difference detection pixel in the central region and a signal acquired by a pixel in an end region in the arrangement direction are formed so as to be read out to the same readout node. A solid-state imaging device;
an optical system that forms a subject image on the solid-state imaging device;
The solid-state imaging device includes:
A pixel unit in which a plurality of pixels, each including a photoelectric conversion unit, are arranged in an array,
In the pixel portion,
A normal pixel group formed by a plurality of pixel units including a plurality of adjacent pixels of the same color;
a phase difference detection pixel group formed to include a greater number of phase difference detection pixels of the same color than the number of pixels forming the pixel unit of the normal pixel group, and for detecting phase difference information for controlling a focusing function;
The phase difference detection pixel group includes
a plurality of same-color pixels are formed in a matrix shape so as to extend in at least one of a first direction and a second direction perpendicular to the first direction;
At least one shared microlens that causes light to enter a photoelectric conversion unit of at least two of the phase difference detection pixels in a central region in an arrangement direction,
the phase difference detection signal acquired by at least one phase difference detection pixel in the central region and the signal acquired by a pixel in an end region in the arrangement direction can be read out to the same readout node.

Images