Photodetection device and imaging device

Abstract

To provide a photodetection device capable of improving the accuracy of a phase difference signal.SOLUTION: A photodetection device is configured to include a semiconductor substrate including a plurality of photoelectric conversion units arranged in an array in row and column directions, a plurality of pixels arranged in the row direction, each pixel including two photoelectric conversion units, and a microlens that is arranged on a light incident surface side of the semiconductor substrate and configured to focus light having passed through an imaging optical system of an imaging device for each pixel. The plurality of pixels include a plurality of special pixels, each of which has a light-shielding film for covering one end side region or the other end side region in the row direction of a light incident surface of a specific photoelectric conversion unit that is at least some of two or more photoelectric conversion units. At least some of the plurality of special pixels are arranged apart from each other in the row direction, and the width in the row direction of the light-shielding film of each special pixel differs depending on the image height in the row direction of the specific photoelectric conversion unit covered by the light-shielding film.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present technology (technology related to the present disclosure) relates to a light detection device and an imaging device. [Background technology]

[0002] Conventionally, for example, a photodetector has been proposed that includes a plurality of pupil division pixels, each of which includes a block including four photoelectric conversion units arranged in a 2×2 array and a microlens that focuses light for each block (see, for example, Patent Document 1). The photodetector described in Patent Document 1 reads out pixel signals from the four photoelectric conversion units and obtains a phase difference signal from the read out pixel signals. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-15430 A Summary of the Invention [Problem to be solved by the invention]

[0004] In such a photodetector, there is a demand for further improvement in the accuracy of the phase difference signal.

[0005] An object of the present disclosure is to provide a photodetection device and an imaging device capable of improving the accuracy of a phase difference signal. [Means for solving the problem]

[0006] The photodetection device disclosed herein comprises (a) a semiconductor substrate including a plurality of photoelectric conversion units arranged in an array in a first direction and a second direction; (b) a plurality of pixels including two or more photoelectric conversion units lined up in the first direction; and (c) a microlens arranged on the light incident surface side of the semiconductor substrate for collecting light that has passed through the imaging optical system of the imaging device for each pixel, wherein (d) the plurality of pixels include a plurality of special pixels, (e) the special pixels have a light-shielding film covering one end side region or the other end side region in the first direction of the light incident surface of a specific photoelectric conversion unit that is at least a part of the two or more photoelectric conversion units, and (f) at least some of the special pixels are arranged apart from each other in the first direction, and the width in the first direction of the light-shielding film of each special pixel differs depending on the image height in the first direction of the specific photoelectric conversion unit that the light-shielding film covers.

[0007] The imaging device disclosed herein comprises (a) a semiconductor substrate including a plurality of photoelectric conversion units arranged in an array in a first direction and a second direction, (b) a plurality of pixels including two or more photoelectric conversion units lined up in the first direction, (c) and a microlens arranged on the light incident surface side of the semiconductor substrate for focusing light that has passed through the imaging optical system of the imaging device for each pixel, (d) the plurality of pixels including a plurality of special pixels, (e) the special pixels having a light-shielding film covering one end side region or the other end side region in the first direction of the light incident surface of a specific photoelectric conversion unit that is at least a part of the two or more photoelectric conversion units, and (f) at least some of the special pixels are arranged apart from each other in the first direction, and a light detection device in which the width in the first direction of the light-shielding film of each special pixel differs depending on the image height in the first direction of the specific photoelectric conversion unit covered by the light-shielding film. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a schematic configuration of an imaging apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a diagram showing a planar configuration of a light receiving element. [Diagram 3] 3 is an enlarged view of the upper left corner of the light receiving element shown in FIG. 2. [Figure 4]4 is a diagram showing a cross-sectional configuration of the light receiving element taken along line AA in FIG. 3. [Diagram 5] 4 is a diagram showing a cross-sectional configuration of the light receiving element taken along line BB in FIG. 3. [Figure 6] 4 is a diagram showing a cross-sectional configuration of the light receiving element taken along line CC in FIG. 3. [Figure 7] 5 is a diagram showing a cross-sectional configuration of a light receiving element taken along line DD in FIG. 4. [Figure 8] FIG. 2 is a diagram showing the potentials of each part of a normal pixel and a special pixel. [Figure 9] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Figure 10] FIG. 11 is a diagram showing a planar configuration of a light receiving element according to a second embodiment. [Figure 11] FIG. 11 is a diagram showing a first group portion of FIG. 10. [Figure 12] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Figure 13] FIG. 2 is a diagram showing a cross-sectional configuration of a light receiving element. [Figure 14] 14 is a diagram showing a cross-sectional configuration of the light receiving element when cut along line EE in FIG. 13. [Figure 15] FIG. 2 is a diagram showing the potentials of each part of a normal pixel and a special pixel. [Figure 16] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Figure 17] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Figure 18] FIG. 13 is a diagram showing a configuration in which a blue pixel is used as a special pixel. [Figure 19] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Figure 20] 20 is an enlarged view of the upper left corner of the light receiving element shown in FIG. 19. [Figure 21] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Figure 22] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Figure 23]11 is a diagram illustrating an image of subtraction between pixel signals performed in a signal processing unit. FIG. [Figure 24] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Diagram 25] 25 is a diagram showing normal pixels at the center of the image height and at high image heights in FIG. 24 . [Figure 26] 25 is a diagram illustrating special pixels at the center of the image height and at high image heights in FIG. 24 . [Figure 27] 25 is a diagram illustrating special pixels at the center of the image height and at high image heights in FIG. 24 . [Figure 28] 11 is a diagram showing the relationship between the incident angle of light and the normalized output of a photoelectric conversion unit. FIG. [Figure 29] FIG. 2 is a diagram showing a pinhole pixel. [Diagram 30] FIG. 13 is a diagram showing a pixel signal of a pinhole pixel. [Diagram 31] FIG. 2 is a diagram showing an island pixel. [Diagram 32] FIG. 4 is a diagram showing pixel signals of an island pixel. [Diagram 33] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Diagram 34] FIG. 2 is a diagram showing the potentials of each part of a normal pixel and a special pixel. [Diagram 35] 13 is a diagram showing a planar configuration of a light receiving element according to a modified example. FIG. [Diagram 36] 36 is an enlarged view of the upper left corner of the light receiving element shown in FIG. 35. FIG. [Figure 37] FIG. 2 is a diagram showing the potentials of each part of a normal pixel and a special pixel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an example of a light detection device and an imaging device according to an embodiment of the present disclosure will be described with reference to FIGS. 1 to 37. The embodiment of the present disclosure will be described in the following order. Note that the present disclosure is not limited to the following example. Also, the effects described in this specification are examples and are not limiting, and other effects may be present. 1. First embodiment 1-1 Configuration of the imaging device 1-2 Photodetector structure 1-3 Operation of the signal processing section 1-4 Pixel separation structure 1-5 Variations 2. Second embodiment 2-1 Main components 2-2 Variations

[0010] The present inventors have discovered the following problem in the photodetector described in Patent Document 1. In the optical detection device described in Patent Document 1, for example, when applied to an interchangeable-lens imaging device, if a camera lens with a pupil distance significantly different from the expected pupil distance (the distance between the imaging surface of the light receiving element and the exit pupil of the camera lens) is attached, an appropriate pixel signal cannot be obtained from the pupil division pixel, and the accuracy of the phase difference signal generated from the pixel signal may decrease.

[0011] 1. First embodiment [1-1 Configuration of imaging device] The configuration of an imaging device according to a first embodiment of the present disclosure will be described. FIG. 1 is a diagram showing a schematic configuration of an image capturing apparatus 100 according to the first embodiment. 1, the imaging device 100 includes a camera lens 101 (broadly speaking, an "imaging optical system"), a solid-state imaging device 102 (broadly speaking, a "photodetector"), a control unit 103, a storage unit 104, and a monitor 105. As the imaging device 100, for example, a lens-interchangeable digital still camera or a digital video camera can be used. The camera lens 101 guides incident light (image light) from a subject to the light receiving element 106, and forms an image on the imaging surface of the light receiving element 106 (for example, the effective pixel area of ​​the pixel area 2 shown in FIG. 2). The solid-state imaging device 102 has a light receiving element 106 and a signal processing unit 107. The light receiving element 106 converts the amount of incident light (image light) imaged on the pixel region 2 (see FIG. 2) by the camera lens 101 into an electrical signal for each pixel. For example, a back-illuminated CMOS image sensor can be used. The converted electrical signal is output to the signal processing unit 107 as a pixel signal. The signal processing unit 107 also generates image data representing a captured image based on the pixel signal output from the light receiving element 106. The signal processing unit 107 also generates a phase difference signal based on the pixel signal. The generated image data and phase difference signal are output to the control unit 103. The control unit 103 controls the storage unit 104 and the monitor 105 so as to store image data output from the signal processing unit 107 and display a captured image. In addition, the control unit 103 controls the camera lens 101 so as to perform focus adjustment based on the phase difference signal output from the signal processing unit 107. The storage unit 104 stores image data generated by the solid-state imaging device 102, various parameters used by the control unit 103, and the like. For example, a flash memory can be used. The monitor 105 displays the captured image represented by the image data on a display surface thereof. For example, a panel-type display device such as a liquid crystal panel or an organic EL (Electro Luminescence) panel can be used. The configuration of the light receiving element 106 and the operation of the signal processing unit 107 will be described below.

[0012] [1-2 Photodetector structure] Next, the configuration of the light receiving element 106 will be described. Fig. 2 is a diagram showing a planar configuration of light receiving element 106. Fig. 3 is an enlarged view of the upper left corner of light receiving element 106 shown in Fig. 2. Fig. 4 is a diagram showing a cross-sectional configuration of light receiving element 106 when cut along line AA in Fig. 3. Fig. 5 is a diagram showing a cross-sectional configuration of light receiving element 106 when cut along line BB in Fig. 3. Fig. 6 is a diagram showing a cross-sectional configuration of light receiving element 106 when cut along line CC in Fig. 3. As shown in FIG. 2 to FIG. 6, the light receiving element 106 has a semiconductor substrate 1 (see FIG. 4), and a pixel region 2 (see FIG. 2) is formed in the semiconductor substrate 1. The pixel region 2 has a plurality of pixels 3 arranged in an array in the row direction (broadly speaking, the "first direction") and the column direction (broadly speaking, the "second direction"). The pixel 3 has two photoelectric conversion units PD1 and PD2. As shown in FIG. 7, the photoelectric conversion units PD1 and PD2 are arranged adjacent to each other in the row direction (left-right direction in FIG. 7) when viewed from the thickness direction of the semiconductor substrate 1, and each of them is formed in a rectangular shape extending in the column direction (up-down direction in FIG. 7). That is, the semiconductor substrate 1 has a plurality of pixels 3, each including two photoelectric conversion units PD1 and PD2 arranged in the row direction (broadly speaking, "two or more photoelectric conversion units arranged in the first direction"), formed to form the pixel region 2, and the plurality of photoelectric conversion units PD1 and PD2 are arranged in an array in the row direction and the column direction. FIG. 7 is a diagram showing a cross-sectional configuration of the light receiving element 106 when broken along the line DD in FIG. 4. FIG. 7 illustrates a case where the photoelectric conversion unit on the right side is PD1 and the photoelectric conversion unit on the left side is PD2. The photoelectric conversion units PD1 and PD2 have a p-type semiconductor region and an n-type semiconductor region, and the pn junction of these semiconductor regions forms a photodiode, which generates electric charge (e.g., electrons) according to the amount of received light. The photoelectric conversion units PD1 and PD2 also accumulate electric charge generated by photoelectric conversion in electrostatic capacitance generated at the pn junction. The accumulated electric charge is converted into pixel signals and output to the signal processing unit 107 in order.

[0013] Also, as shown in FIG. 2, the pixel region 2 includes, as pixels 3, a plurality of normal pixels 4 and a plurality of special pixels 5. The normal pixel 4 is a pixel for obtaining a pixel signal for generating image data during normal shooting. For example, a red pixel R, a blue pixel B, green pixels Gr, and Gb can be mentioned. Examples of the pixel signal for generating image data include the total value of pixel signals based on the charges generated by the photoelectric conversion units PD1 and PD2. Also, the normal pixel 4 is a pixel for obtaining a pixel signal for generating a phase difference signal when a camera lens 101 having a basic pupil distance EPD0 (broadly, "predetermined pupil distance") is attached to the imaging device 100 during focus adjustment of the camera lens 101. Further, the special pixel 5 is a pixel for obtaining a pixel signal for generating a phase difference signal when a camera lens 101 having a first pupil distance EPD1, a second pupil distance EPD2, or a third pupil distance EPD3 (broadly, "predetermined pupil distance") is attached to the imaging device 100 during focus adjustment of the camera lens 101. The magnitude relationship of EPD0, EPD1, EPD2, and EPD3 is in the order of EPD2 < EPD0 < EPD3 < EPD1. As shown in FIG. 4, the pupil distance EPD can be the distance between the imaging surface of the light receiving element 106 and the exit pupil 55 of the camera lens 101. Also, in the pixel region 2, as shown in FIG. 3, four pixels 3 arranged in a 2×2 array constitute a plurality of first blocks 6 and a plurality of second blocks 7. The first block 6 is a block in which four normal pixels 4 are arranged in a Bayer pattern. The second block 7 is a block formed by replacing the normal pixel 4 that constitutes the green pixel Gb of the first block 6 with a special pixel 5. In FIG. 2, a case where the special pixel 5 has a color filter 54 (see FIGS. 5 and 6) that passes green light is illustrated. For ease of viewing the drawings, in FIGS. 1, 2, etc., the dot pattern indicating the color filter 54 of the special pixel 5 is omitted.

[0014] As shown in FIG. 2, the second blocks 7 are arranged to form a block pair 8 in which two second blocks 7 are arranged in the column direction (vertical direction in FIG. 2). The block pairs 8 are arranged to form groups (hereinafter also referred to as "first group 9", "second group 10", and "third group 11") in which a plurality of block pairs 8 are arranged in the row direction (horizontal direction in FIG. 2). The special pixels 5 of the first group 9 are pixels for acquiring pixel signals for generating a phase difference signal when a camera lens 101 (short pupil lens) with a first pupil distance EPD1 is attached. The special pixels 5 of the second group 10 are pixels for acquiring pixel signals for generating a phase difference signal when a camera lens 101 (long pupil lens) with a second pupil distance EPD2 is attached. The special pixels 5 of the third group 11 are pixels for acquiring pixel signals for generating a phase difference signal when a camera lens 101 (medium pupil lens) with a third pupil distance EPD3 is attached. Figure 2 illustrates an example in which the first group 9 is located at one end of the column (the top end in the vertical direction in Figure 2), followed by the second group 10 at the other end of the column (the bottom end in the vertical direction in Figure 2), and the third group 11 between the first group 9 and the second group 10 (the middle in the vertical direction in Figure 2). With such an arrangement of the pixels 3 (normal pixels 4, special pixels 5), each of the first group 9, second group 10, and third group 11 is configured to include a first pixel group 12 consisting of a plurality of special pixels 5 arranged apart from each other in the row direction (left-right direction in FIG. 2), and a second pixel group 13 consisting of a plurality of special pixels 5 arranged apart from each other in the row direction (left-right direction in FIG. 2) at a position spaced apart in the column direction (up-down direction in FIG. 2) from the first pixel group 12. The special pixels 5 of the first pixel group 12 and the special pixels 5 of the second pixel group 13 are arranged at the same row position (left-right position in FIG. 2).

[0015] 4, 5, and 6, a plurality of microlenses 14 are arranged on the light incident surface (hereinafter also referred to as "rear surface S1") side of the semiconductor substrate 1. One microlens 14 is arranged for each pixel 3, and the light L passing through the camera lens 101 of the imaging device 100 (see FIG. 1) is collected for each pixel 3. The collected light passes through a color filter 54 (red filter, blue filter, green filter) formed for each pixel 3 and is incident on each of the photoelectric conversion units PD1 and PD2. Here, each of the microlenses 14 is arranged at a position where pupil correction has been performed. That is, when viewed from the thickness direction of the semiconductor substrate 1, the center of the microlens 14 is shifted toward the center of the pixel region 2 from the center of the pixel 3 toward the outer periphery of the pixel region 2. 4 illustrates a case where, when viewed from the thickness direction of the semiconductor substrate 1, the microlens 14 is disposed at a pupil-corrected position such that a light collection area X of light that passes through the camera lens 101 having the basic pupil distance EPD0 and is collected by the microlens 14 overlaps with the center of the pixel 3. By disposing the microlens 14 at a pupil-corrected position, when the camera lens 101 having the basic pupil distance EPD0 is attached to the imaging device 100, the position of the light collection area X can be adjusted to the center of the pixel 3 (between the photoelectric conversion units PD1 and PD2) on the outer periphery side (high image height side) of the pixel area 2.

[0016] 5 and 6, the special pixel 5 has a light-shielding film 15 on the back surface S1 side of the semiconductor substrate 1 (on the back surface S3 of the insulating film 29 in FIG. 5 and FIG. 6). The light-shielding film 15 covers one end side region or the other end side region in the row direction (right side region or left side region in FIG. 3; in a broad sense, one end side region or the other end side region in the first direction of the light incident surface of the specific photoelectric conversion unit that is at least a part of two or more photoelectric conversion units) of one of the two photoelectric conversion units PD1 and PD2 of the special pixel 5 (hereinafter, also referred to as the "back surface S2") (the right side region or the left side region in FIG. 3; in a broad sense, one end side region or the other end side region in the first direction of the light incident surface of the specific photoelectric conversion unit that is at least a part of two or more photoelectric conversion units). The specific photoelectric conversion unit 16 is a photoelectric conversion unit in which a light collection region X of light L is located in the special pixel 5 for acquiring a phase difference signal corresponding to a pupil distance EPD1, EPD2, or EPD3 when a camera lens 101 having the pupil distance EPD1, EPD2, or EPD3 is attached. Here, when the pupil distance EPD of the camera lens 101 is a short pupil shorter than the basic pupil distance EPD0, the angle of incidence of light L to the light receiving element 106 becomes large, the light collection region X shifts toward the outer periphery of the pixel region 2 (high image height side), and the light collection region X moves into the photoelectric conversion unit PD1 or PD2 toward the outer periphery of the pixel region 2. On the other hand, when the pupil distance EPD of the camera lens 101 is a long pupil longer than the basic pupil distance EPD0, the angle of incidence of light L to the light receiving element 106 becomes small, the light collection region X shifts toward the center of the pixel region 2 (image height central side), and the light collection region X moves into the photoelectric conversion unit PD1 or PD2 on the center side of the pixel region 2. Therefore, when a camera lens 101 having a pupil distance other than the basic pupil distance EPD0 (first pupil distance EPD1, first pupil distance EPD1, first pupil distance EPD1) is attached to the imaging device 100, the light collection area X will be positioned away from the center of the pixel 3 and within the photoelectric conversion unit PD1 or PD2.

[0017] Furthermore, the specific photoelectric conversion unit 16 is constituted by a photoelectric conversion unit pair 17 made up of two specific photoelectric conversion units 16 arranged at the same row direction position (left-right direction position in FIG. 3) among the specific photoelectric conversion unit 16 of the special pixel 5 of the first pixel group 12 and the specific photoelectric conversion unit 16 of the special pixel 5 of the second pixel group 13. The photoelectric conversion unit pair 17 includes a first specific photoelectric conversion unit 18 located on one side in the row direction (right or left side in FIG. 3) of one special pixel 5 (special pixel 5 of the first pixel group 12 in FIG. 3) and having one end side region in the row direction of the light incident surface (right side region or left side region in FIG. 3) covered with a light-shielding film 15. Also, the second specific photoelectric conversion unit 19 is located on one side (right or left side in FIG. 3) of another special pixel 5 (special pixel 5 of the second pixel group 13 in FIG. 3) in the row direction and has the other end side region in the row direction of the light incident surface (left region or right region in FIG. 3) covered with the light shielding film 15. Also, the row direction width W1 (or W4) of the light shielding film 15 covering the light incident surface of the first specific photoelectric conversion unit 18 included in the same photoelectric conversion unit pair 17 is equal to the row direction width W3 (or W2) of the region of the light incident surface of the second specific photoelectric conversion unit 19 that is not covered with the light shielding film 15. Also, the row direction widths W1 and W4 of the light shielding film 15 (left and right direction in FIG. 3) differ depending on the image height in the row direction (left and right direction in FIG. 3) of the specific photoelectric conversion unit 16 covered by the light shielding film 15. For example, when viewed from the thickness direction of the semiconductor substrate 1, the row direction widths W1 and W4 of the light-shielding film 15 are sized so that a light-collection region X of light L that passes through a camera lens 101 having a predetermined pupil distance (any of the first pupil distance EPD1, the second pupil distance EPD2, and the third pupil distance EPD3) and is collected by the microlens 14 overlaps with the row direction end of the light-shielding film 15. In other words, the widths W1 and W4 of the light-shielding film 15 are sized to block half of the light-collection region X and to pass the remaining half. As a result, light that passes through one side of the row direction of the exit pupil 55 of the camera lens 101 is blocked, and light that passes through the other side can pass. Figure 2 shows an example in which the widths W1 and W4 of the light-shielding film 15 of the special pixels 5 in the first group 9 are adjusted to a width corresponding to the first pupil distance EPD1, the widths W1 and W4 of the light-shielding film 15 of the special pixels 5 in the second group 10 are adjusted to a width corresponding to the second pupil distance EPD2, and the widths W1 and W4 of the light-shielding film 15 of the special pixels 5 in the third group 11 are adjusted to a width corresponding to the third pupil distance EPD3.Examples of materials for the light-shielding film 15 include tungsten (W) and aluminum (Al).

[0018] With this arrangement of the light-shielding films 15, as shown in FIG. 2, when viewed from the thickness direction of the semiconductor substrate 1, the light-shielding film 15 includes a first light-shielding film 20 (the light-shielding films 15 in the second and fourth rows from the top in FIG. 2) whose row-wise widths W1, W4 are large enough to allow the collection area X of light L that passes through a camera lens 101 having a predetermined first pupil distance EPD1 and is collected by the microlens 14 to overlap with the row-wise end of the light-shielding film 15, and a second light-shielding film 21 (the light-shielding films 15 in the first and third rows from the bottom in FIG. 2) whose row-wise widths W1, W4 are large enough to allow the collection area X of light L that passes through a camera lens 101 having a second pupil distance EPD2 different from the first pupil distance EPD1 and is collected by the microlens 14 to overlap with the row-wise end of the light-shielding film 15. The multiple photoelectric conversion unit pairs 17 are configured to include a first specific photoelectric conversion unit pair 22 (a pair of specific photoelectric conversion units 16 in the second and fourth rows from the top in Figure 2) in which the light shielding film 15 covering the light incident surfaces of the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 is the first light shielding film 20, and a second specific photoelectric conversion unit pair 23 (a pair of specific photoelectric conversion units 16 in the first and third rows from the bottom in Figure 2) in which the light shielding film 15 covering the light incident surfaces of the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 is the second light shielding film 21.

[0019] [1-3 Operation of the signal processing section] Next, the operation of the signal processing unit 107 will be described. During normal shooting, the signal processing unit 107 generates image data representing a captured image based on pixel signals output from the light receiving element 106. When generating the image data, the sum of pixel signals from the two photoelectric conversion units PD1 and PD2 of a normal pixel 4 is used as the pixel signal of the normal pixel 4. In addition, the pixel signal of the special pixel 5 is complemented using the pixel signal of the normal pixel 4. Furthermore, when adjusting the focus of the camera lens 101, the signal processing unit 107 generates a phase difference signal based on pixel signals from the photoelectric conversion units PD1 and PD2 of the normal pixel 4 or the special pixel 5. The normal pixel 4 and the special pixel 5 used to acquire the phase difference signal are changed according to the pupil distance EPD of the camera lens 101 attached to the imaging device 100. For example, when a camera lens 101 having a basic pupil distance EPD0 is attached, the light collection area X is located at the center of each pixel 3 (between the photoelectric conversion units PD1 and PD2). Therefore, separate incident light (light that has passed through one side in the row direction of the exit pupil 55 of the camera lens 101 and light that has passed through the other side) is incident on the two photoelectric conversion units PD1 and PD2 of the normal pixel 4. Therefore, when a camera lens 101 having a basic pupil distance EPD0 is attached, the signal processing unit 107 generates a phase difference signal based on pixel signals from the two photoelectric conversion units PD1 and PD2 of the normal pixel 4.

[0020] Also, for example, when a camera lens 101 having a first pupil distance EPD1 is attached, the light collection region X is located on an end of the light shielding film 15 of the special pixel 5 of the first group 9 in the row direction as shown in FIG. 2. Therefore, different incident light (light passing through one side in the row direction of the exit pupil 55 of the camera lens 101 and light passing through the other side in the row direction) is incident on the two specific photoelectric conversion units 16 of the two special pixels 5 constituting the photoelectric conversion unit pair 17. Therefore, when a camera lens 101 having a first pupil distance EPD1 is attached, the signal processing unit 107 generates a phase difference signal based on pixel signals of the two specific photoelectric conversion units 16 constituting the photoelectric conversion unit pair 17 in the first group 9. Similarly, when a camera lens 101 having a second pupil distance EPD2 is attached, the signal processing unit 107 generates a phase difference signal based on pixel signals of the two specific photoelectric conversion units 16 constituting the photoelectric conversion unit pair 17 in the second group 10. In addition, when a camera lens 101 having a third pupil distance EPD3 is attached, the signal processing unit 107 generates a phase difference signal based on the pixel signals of two specific photoelectric conversion units 16 that constitute a photoelectric conversion unit pair 17 in the third group 11.

[0021] Here, for example, if the pixel region 2 is configured to have only normal pixels 4, when a camera lens 101 having a pupil distance significantly different from the basic pupil distance EPD0 is attached, an appropriate pixel signal cannot be obtained from the normal pixels 4, and the accuracy of the phase difference signal generated from the pixel signal decreases. 2, the imaging device 100 according to the first embodiment has special pixels 5 each having a light-shielding film 15, and the row-direction widths W1 and W4 of the light-shielding film 15 of each special pixel 5 are different depending on the row-direction image height of the specific photoelectric conversion unit 16 covered by the light-shielding film 15. As a result, for example, when a camera lens 101 having a pupil distance significantly different from the basic pupil distance EPD0 is attached, a pixel signal from the specific photoelectric conversion unit 16 of the special pixel 5 is acquired, and a phase difference signal can be generated based on the acquired pixel signal. Therefore, the accuracy of the phase difference signal can be improved for camera lenses 101 having a plurality of pupil distances EPD.

[0022] [1-4 Configuration of pixel separation structure] Next, the configuration of the pixel separation structure 24 will be described. As shown in FIG. 4, a pixel separation structure 24 is formed between the photoelectric conversion units PD1 and PD2 in the semiconductor substrate 1. That is, the pixel separation structure 24 is formed in a lattice shape on the semiconductor substrate 1 so as to surround each of the multiple photoelectric conversion units PD1 and PD2. Also, as shown in FIG. 7, the pixel separation structure 24 has a portion surrounding the periphery of a block composed of the photoelectric conversion units PD1 and PD2 in the same pixel 3 (hereinafter also referred to as an "inter-pixel separation unit 25"), and a portion located between the photoelectric conversion units PD1 and PD2 in the region surrounded by the inter-pixel separation unit 25 (hereinafter also referred to as an "intra-pixel separation unit 26"). The inter-pixel separation unit 25 has a trench unit 27, and a fixed charge film 28 and an insulating film 29 arranged in the trench unit 27. The trench unit 27 penetrates the semiconductor substrate 1 from the back surface S1 to the front surface S4 of the semiconductor substrate 1, and the sidewall surface forms the outline of the pixel separation structure 24. The fixed charge film 28 continuously covers the sidewall surface of the trench portion 27 and the rear surface S1 of the semiconductor substrate 1. For example, a negatively charged high refractive index material film or a high dielectric film can be used as the material of the fixed charge film 28. The insulating film 29 is disposed in the space between the sidewall surfaces covered with the fixed charge film 28. In addition to the space, the insulating film 29 also covers the light incident surface of the fixed charge film 28 located on the rear surface S1 of the semiconductor substrate 1.

[0023] As shown in FIG. 7, the intra-pixel separation section 26 is formed in a strip shape extending along the column direction (vertical direction in FIG. 7) when viewed in the thickness direction of the semiconductor substrate 1, and each end side in the longitudinal direction has the same internal structure as the inter-pixel separation section 25, and has an impurity layer 30 in the center. The impurity layer 30 is formed from the front surface S4 side to the back surface S1 side, similar to the inter-pixel separation section 25. For example, a semiconductor region formed by doping the semiconductor substrate 1 with a p-type impurity can be used as the impurity layer 30. For example, boron (B) can be used as the p-type impurity. With this configuration, the impurity layer 30 functions as an overflow path (hereinafter also referred to as a "first overflow path 31") that allows the passage of charges from one side to the other side between the adjacent photoelectric conversion sections PD1 and PD2. Therefore, for example, in a normal pixel 4, when the charge of one of the photoelectric conversion units PD1, PD2 becomes saturated during normal shooting, the charge can be transferred to the other photoelectric conversion unit via the first overflow path 31, thereby avoiding saturation of the charge of the photoelectric conversion units PD1, PD2.

[0024] As shown in FIG. 4, a floating diffusion FD is formed in the impurity layer 30 on the surface S4 of the semiconductor substrate 1. For example, a semiconductor region formed by doping the semiconductor substrate 1 with n-type impurities can be used as the floating diffusion FD. A p-well region pwell is formed on the surface S4 of the semiconductor substrate 1. In the p-well region pwell, an element isolation region STI for isolating pixel transistors and the like and a pixel transistor (for example, a transfer transistor 32) are formed. The transfer transistor 32 is, for example, an n-channel conductive MOSFET. The transfer transistor 32 is configured to form a channel between the photoelectric conversion units PD1 and PD2 and the floating diffusion FD, and has a gate insulating film 33 and a gate electrode 34 sequentially stacked on the surface S4 of the semiconductor substrate 1. The transfer transistor 32 is turned on and off according to the voltage between the gate and source, thereby enabling the signal charge to be transferred from the photoelectric conversion units PD1 and PD2 functioning as source regions to the floating diffusion FD functioning as a drain region. The region in which the channel is formed by the transfer transistor 32 also functions as an overflow path (hereinafter also referred to as a "second overflow path 35") that allows charge to pass from the photoelectric conversion units PD1 and PD2 to the floating diffusion FD. Therefore, for example, in the normal pixel 4, when the charge of the photoelectric conversion units PD1 and PD2 becomes saturated, the charge can be moved to the floating diffusion FD via the second overflow path 35, and saturation of the charge of the photoelectric conversion units PD1 and PD2 can be avoided.

[0025] As shown in FIG. 8, in the normal pixel 4, the deepest potential PD Vmax and the deepest part of the potential of the first overflow path 31 OF Vmax and the deepest TG of the potential of the second overflow path 35 Vmax The relationship between PD and Vmax >OF Vmax >T.G. VmaxAs a result, when the charge in one of the photoelectric conversion units PD1 and PD2 in the normal pixel 4 becomes saturated, the charge moves to the other photoelectric conversion unit, and when the charge in the other photoelectric conversion unit also becomes saturated, the charge moves to the floating diffusion FD. Vmax , OF Vmax and T.G. Vmax The magnitude relationship can be realized by adjusting the photoelectric conversion units PD1 and PD2, the p-well region pwell, the impurity concentrations of the impurity layer 30, and the like.

[0026] In addition, in Special Pixel 5, PD Vmax , OF Vmax and T.G. Vmax The relationship between the magnitude of PD Vmax >T.G. Vmax >OF Vmax In other words, the potential of the second overflow path 35, which transfers the charge overflowing from the photoelectric conversion units PD1 and PD2 of the special pixel 5 to the floating diffusion FD, is deeper than the potential of the first overflow path 31, which transfers the charge between the two photoelectric conversion units PD1 and PD2 included in the special pixel 5. As a result, when the charge of one of the photoelectric conversion units PD1 and PD2 in the special pixel 5 becomes saturated, the charge does not move to the other photoelectric conversion unit, but moves only to the floating diffusion FD. Therefore, the transfer of charge between the specific photoelectric conversion unit 16 and the photoelectric conversion unit adjacent to the specific photoelectric conversion unit 16 can be suppressed, and the deterioration of the accuracy of the phase difference signal can be suppressed.

[0027] [1-5 Modifications] (1) In the first embodiment, as shown in FIG. 2, an example is shown in which the first specific photoelectric conversion unit pair 22 is formed of the photoelectric conversion unit pair 17 of the first group 9, and the second specific photoelectric conversion unit pair 23 is formed of the photoelectric conversion unit pair 17 of the second group 10. However, other configurations can be adopted. For example, as shown in FIG. 9, the first specific photoelectric conversion unit pair 22 and the second specific photoelectric conversion unit pair 23 may be formed of the photoelectric conversion unit pairs 17 of one group. FIG. 9 illustrates a case in which the photoelectric conversion unit PD1 or PD2 located on one side (left side or right side in FIG. 9) in the row direction of two specific special pixels 5 (special pixels 5 in the second row and the fourth row from the top in FIG. 9) is the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 of the first specific photoelectric conversion unit pair 22, respectively. 9 illustrates a case where the photoelectric conversion unit PD1 or PD1 located on the other side (the right side or the left side in FIG. 9) of the two special pixels 5 in the row direction is the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 of the second specific photoelectric conversion unit pair 23. More specifically, in FIG. 9, the second specific photoelectric conversion unit pair 23 corresponding to the camera lens 101 (long pupil lens) having the second pupil distance EPD2 is located on the center side of the pixel region 2, and the first specific photoelectric conversion unit pair 22 corresponding to the camera lens 101 (short pupil lens) having the first pupil distance EPD1 is located on the outer periphery side of the pixel region 2. With this configuration, the two photoelectric conversion units PD1 and PD2 of the special pixel 5 can be used as the specific photoelectric conversion units 16, and the photoelectric conversion units PD1 and PD2 of the special pixel 5 can be used more efficiently. Therefore, the number of available pupil distances EPD can be increased without increasing the number of special pixels 5.

[0028] 2. Second embodiment [2-1 Configuration of main parts] Next, an imaging device 100 according to a second embodiment of the present disclosure will be described. The overall configuration of the imaging device 100 of the second embodiment is the same as that of FIG. 1, and therefore will not be illustrated. FIG. 10 is a diagram corresponding to FIG. 2 of the first embodiment. Also, FIG. 11 is a diagram showing the first group 9 portion of FIG. 10. Also, FIG. 13 is a diagram corresponding to FIG. 7 of the first embodiment. In FIG. 11 and FIG. 13, the parts corresponding to FIG. 2 and FIG. 7 are given the same reference numerals, and duplicated explanations will be omitted. The second embodiment differs from the first embodiment in that a pixel 3 includes four photoelectric conversion units PD1, PD2, PD3, and PD4 arranged in a 2 × 2 array, as shown in Figures 10 and 11. Figure 11 illustrates a case in which the photoelectric conversion unit on the upper right side is PD1, the photoelectric conversion unit on the upper left side is PD2, the photoelectric conversion unit on the lower right side is PD3, and the photoelectric conversion unit on the lower left side is PD4. In the second embodiment, one pair of photoelectric conversion units out of two pairs of photoelectric conversion units (a pair of PD1 and PD3, and a pair of PD2 and PD4 in FIG. 11) arranged in the column direction included in the special pixel 5 is used as the specific photoelectric conversion unit 16. As a result, by using the sum of the pixel signals of the pair of photoelectric conversion units instead of the pixel signal of the specific photoelectric conversion unit 16 of the first embodiment, a phase difference signal can be generated similarly to the first embodiment. For example, in the special pixel 5 in the second row from the top and the third row from the left in FIG. 11, the photoelectric conversion units PD2 and PD4 serve as the specific photoelectric conversion unit 16.

[0029] Further, the specific photoelectric conversion unit 16 is constituted by two specific photoelectric conversion units 16 arranged at the same row direction position (left-right direction position in FIG. 11) among the specific photoelectric conversion unit 16 of the special pixel 5 of the first pixel group 12 and the specific photoelectric conversion unit 16 of the special pixel 5 of the second pixel group 13. The photoelectric conversion unit pair 17 includes two first specific photoelectric conversion units 18 located on one side in the row direction (right or left side in FIG. 11) of one special pixel 5 (special pixel 5 of the first pixel group 12 in FIG. 11) and having one end side region in the row direction of the light incident surface (right side region or left side region in FIG. 11) covered with a light-shielding film 15. Also, it includes two second specific photoelectric conversion units 19 that are located on one side (right or left side in FIG. 11) in the row direction of another special pixel 5 (special pixel 5 of the second pixel group 13 in FIG. 11) and have the other end side region in the row direction of the light incident surface (left side region or right side region in FIG. 11) covered with a light shielding film 15. Also, the row direction width W1 (or W4) of the light shielding film 15 covering the light incident surface of the first specific photoelectric conversion unit 18 included in the same photoelectric conversion unit pair 17 is equal to the row direction width W3 (or W2) of the region of the light incident surface of the second specific photoelectric conversion unit 19 that is not covered with the light shielding film 15. When viewed from the thickness direction of the semiconductor substrate 1, the row direction widths W1 and W4 of the light-shielding film 15 are set to a size such that a light-collection region X of light L that passes through a camera lens 101 having a predetermined pupil distance (any of the first pupil distance EPD1, the second pupil distance EPD2, and the third pupil distance EPD3) and is collected by the microlens 14 overlaps with the row direction end of the light-shielding film 15. In other words, the widths W1 and W4 of the light-shielding film 15 are set to block half of the light-collection region X and to pass the remaining half. As a result, light that passes through one side in the row direction of the exit pupil 55 of the camera lens 101 is blocked, and light that passes through the other side can pass. Figures 10 and 11 show an example in which the widths W1 and W4 of the light-shielding film 15 of the special pixels 5 in the first group 9 (see Figures 10 and 11) are adjusted to a width corresponding to the first pupil distance EPD1, the widths W1 and W4 of the light-shielding film 15 of the special pixels 5 in the second group 10 (see Figure 10) are adjusted to a width corresponding to the second pupil distance EPD2, and the widths W1 and W4 of the light-shielding film 15 of the special pixels 5 in the third group 11 (see Figure 10) are adjusted to a width corresponding to the third pupil distance EPD3.

[0030] With this arrangement of the light-shielding films 15, as shown in FIG. 10, when viewed from the thickness direction of the semiconductor substrate 1, the light-shielding film 15 includes a first light-shielding film 20 (the light-shielding films 15 in the second and fourth rows from the top in FIG. 10) whose row-wise widths W1, W4 are large enough to allow the collection area X of light L that passes through a camera lens 101 having a predetermined first pupil distance EPD1 and is collected by the microlens 14 to overlap with the row-wise end of the light-shielding film 15, and a second light-shielding film 21 (the light-shielding films 15 in the first and third rows from the bottom in FIG. 2) whose row-wise widths W1, W4 are large enough to allow the collection area X of light L that passes through a camera lens 101 having a second pupil distance EPD2 different from the first pupil distance EPD1 and is collected by the microlens 14 to overlap with the row-wise end of the light-shielding film 15. The plurality of photoelectric conversion unit pairs 17 are configured to include a first specific photoelectric conversion unit pair 22 (a pair of specific photoelectric conversion units 16 in the second and fourth rows from the top in FIG. 10) in which the light shielding film 15 covering the light incidence surfaces of the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 is the first light shielding film 20, and a second specific photoelectric conversion unit pair 23 (a pair of specific photoelectric conversion units 16 in the first and third rows from the bottom in FIG. 10) in which the light shielding film 15 covering the light incidence surfaces of the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 is the second light shielding film 21. Note that, in the special pixel 5 at the center (center of image height) of the pixel region 2, the incident angle of the light L is 0°, so that the light shielding film 15 may be omitted as shown in FIG. 12.

[0031] In the second embodiment, as shown in FIG. 13, the intra-pixel isolation section 26 is located between the photoelectric conversion sections PD1, PD2, PD3, and PD4 in the region surrounded by the inter-pixel isolation section 25, and is formed in a cross shape extending along the row direction (horizontal direction in FIG. 13) and the column direction (vertical direction in FIG. 13) when viewed from the thickness direction of the semiconductor substrate 1. The intra-pixel isolation section 26 is entirely formed of an impurity layer 30. As a result, the impurity layer 30 functions as an overflow path (hereinafter, "second overflow path 36") that enables the passage of electric charges from one side to the other between the two photoelectric conversion sections PD1 and PD3, and PD2 and PD4 arranged in the column direction (vertical direction in FIG. 13). The impurity layer 30 also functions as an overflow path (hereinafter, "third overflow path 37") that enables the passage of electric charges from one side to the other between the two photoelectric conversion sections PD1 and PD2, and PD3 and PD4 arranged in the row direction (horizontal direction in FIG. 13). Therefore, for example, in a normal pixel 4, when the charge of one of the photoelectric conversion units PD1, PD2, PD3, and PD4 becomes saturated during normal shooting, the charge can be moved to the other photoelectric conversion unit via the second overflow path 36 or the third overflow path 37, thereby preventing the charge of the photoelectric conversion units PD1 to PD4 from becoming saturated.

[0032] 14, a floating diffusion FD is formed in the impurity layer 30 on the surface S4 side of the semiconductor substrate 1. A p-well region pwell is formed on the surface S4 side of the semiconductor substrate 1. In the p-well region pwell, an element isolation region STI for isolating pixel transistors and the like and a pixel transistor (for example, a transfer transistor 32) are formed. The transfer transistor 32 is configured to form a channel between the photoelectric conversion units PD1, PD2, PD3, PD4 and the floating diffusion FD, and has a gate insulating film 33 and a gate electrode 34 sequentially stacked on the surface S4 of the semiconductor substrate 1. The transfer transistor 32 is turned on and off according to the voltage between the gate and source, so that it is possible to transfer signal charges from the photoelectric conversion units PD1, PD2, PD3, PD4 functioning as a source region to the floating diffusion FD functioning as a drain region. The region in which the channel is formed by the transfer transistor 32 functions as an overflow path (hereinafter also referred to as a "first overflow path 38") that allows charges to pass from the photoelectric conversion units PD1 to PD4 to the floating diffusion FD. Therefore, for example, in the normal pixel 4, when the charges of the photoelectric conversion units PD1 to PD4 are saturated, the charges can be moved to the floating diffusion FD via the first overflow path 38, and saturation of the charges of the photoelectric conversion units PD1 to PD4 can be avoided. Fig. 14 is a diagram showing a cross-sectional configuration of the light receiving element 106 when broken along line EE in Fig. 13.

[0033] Here, as shown in FIG. 15, in the normal pixel 4, the deepest potential PD Vmax and OF2, the deepest part of the potential of the second overflow path 36 Vmax and OF3, the deepest part of the potential of the third overflow path 37 Vmax and the deepest TG of the potential of the first overflow path 38 Vmax The relationship between the magnitude and PD Vmax >OF2 Vmax >OF3 Vmax >T.G. VmaxAs a result, when the charge of any of the photoelectric conversion units PD1 to PD4 of the normal pixel 4 becomes saturated, the charge moves to the photoelectric conversion unit in the same column as the photoelectric conversion unit whose charge is saturated, and when the charge of the photoelectric conversion unit in the same column also becomes saturated, the charge moves to the photoelectric conversion unit in the same row as the photoelectric conversion unit whose charge is saturated, and when the charge of the photoelectric conversion unit in the same row also becomes saturated, the charge moves to the floating diffusion FD. PD Vmax , OF2 Vmax , OF3 Vmax and T.G. Vmax The magnitude relationship can be realized by adjusting the photoelectric conversion units PD1 to PD4, the p-well region pwell, the impurity concentrations of the impurity layer 30, and the like.

[0034] In addition, in Special Pixel 5, PD Vmax , OF2 Vmax , OF3 Vmax and T.G. Vmax The relationship between the magnitude of PD Vmax >OF2 Vmax >T.G. Vmax >OF3 Vmax In other words, the potential of the second overflow path 36, which transfers electric charges between two photoelectric conversion units arranged in the column direction among the four photoelectric conversion units PD1 to PD4 included in the special pixel 5, is the deepest, the potential of the first overflow path 38, which transfers electric charges overflowing from the photoelectric conversion units PD to PD4 of the special pixel 5 to the floating diffusion FD, is the second deepest, and the potential of the third overflow path 37, which transfers electric charges between two photoelectric conversion units arranged in the row direction among the four photoelectric conversion units PD1 to PD4 included in the special pixel 5, is the third deepest. As a result, in the special pixel 5, when the electric charge of any of the photoelectric conversion units PD1 to PD4 becomes saturated, the electric charge moves to the photoelectric conversion unit in the same column as the photoelectric conversion unit in which the electric charge is saturated, and when the electric charge of the photoelectric conversion unit in the same column also becomes saturated, the electric charge moves to the floating diffusion FD. Therefore, charge transfer between a specific photoelectric conversion unit 16 and a photoelectric conversion unit in the same row as the specific photoelectric conversion unit 16 can be suppressed, and deterioration in accuracy of the phase difference signal can be suppressed.

[0035] [2-2 Modified Example] (1) In the second embodiment, as shown in FIG. 10, an example is shown in which the first specific photoelectric conversion unit pair 22 is formed by the photoelectric conversion unit pair 17 of the first group 9, and the second specific photoelectric conversion unit pair 23 is formed by the photoelectric conversion unit pair 17 of the second group 10. However, other configurations can also be adopted. For example, as shown in FIG. 16, the first specific photoelectric conversion unit pair 22 and the second specific photoelectric conversion unit pair 23 may be formed by the photoelectric conversion unit pairs 17 of one group. FIG. 16 illustrates a case in which a pair of photoelectric conversion units PD1 and PD3 or PD2 and PD4 located on one side (right side or left side in FIG. 16) in the row direction of two specific special pixels 5 (special pixels 5 in the second row and the fourth row from the top in FIG. 16) are the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 of the first specific photoelectric conversion unit pair 22. 16 illustrates an example in which a pair of photoelectric conversion units PD2 and PD4 or PD1 and PD3 located on the other side (left side or right side in FIG. 16) of the two special pixels 5 in the row direction are respectively configured as the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 of the second specific photoelectric conversion unit pair 23. With this configuration, the four photoelectric conversion units PD1 to PD4 of the special pixel 5 can be used as the specific photoelectric conversion units 16, and the photoelectric conversion units PD1 to PD4 of the special pixel 5 can be used more efficiently. Therefore, the number of applicable pupil distances EPD can be increased without increasing the number of special pixels 5. Note that, since the angle of incidence of the light L is 0° in the special pixel 5 at the center (center of image height) of the pixel area 2, the light shielding film 15 may be omitted as shown in FIG. 17. (2) In the second embodiment, an example is shown in which the green pixel Gb is replaced with the special pixel 5 as shown in Fig. 10, but other configurations can also be adopted. For example, as shown in Fig. 18, a configuration may be adopted in which the pixels 3 other than the green pixel Gb (the red pixel R, the blue pixel B, and the green pixel Gr) are replaced with the special pixel 5. Fig. 18 illustrates an example in which the blue pixel B is used as the special pixel 5.

[0036] (3) In the second embodiment, a pair of photoelectric conversion units among two pairs of photoelectric conversion units (a pair of PD1 and PD3, and a pair of PD2 and PD4) of the special pixel 5 is used as the specific photoelectric conversion unit 16 of the first embodiment, but other configurations can be adopted. For example, as shown in FIG. 19 and FIG. 20, one of the four photoelectric conversion units PD1 to PD4 included in the special pixel 5 may be used as the specific photoelectric conversion unit 16 of the first embodiment. As a result, a phase difference signal can be generated similarly to the first embodiment by using a pixel signal of one of the four photoelectric conversion units PD1 to PD4 instead of the pixel signal of the specific photoelectric conversion unit 16 of the first embodiment. For example, in the special pixel 5 in the second row from the top and the third row from the left in FIG. 19, the photoelectric conversion units PD2 and PD4 are each the specific photoelectric conversion unit 16. FIG. 20 is an enlarged view of the upper left corner of the light receiving element 106 shown in FIG. 19.

[0037] Further, the specific photoelectric conversion unit 16 is constituted by two specific photoelectric conversion units 16 arranged at the same row direction position (left-right direction position in FIG. 19) among the specific photoelectric conversion unit 16 of the special pixel 5 of the first pixel group 12 and the specific photoelectric conversion unit 16 of the special pixel 5 of the second pixel group 13. The photoelectric conversion unit pair 17 includes a first specific photoelectric conversion unit 18 located on one side in the row direction (right or left side in FIG. 19) of one special pixel 5 (special pixel 5 of the first pixel group 12 in FIG. 19) and having one end side region in the row direction of the light incident surface (right side region or left side region in FIG. 19) covered with a light-shielding film 15. Also, it includes a second specific photoelectric conversion unit 19 that is located on one side (right or left side in FIG. 19) in the row direction of another special pixel 5 (special pixel 5 of the second pixel group 13 in FIG. 19) and has the other end side region in the row direction of the light incident surface (left side region or right side region in FIG. 19) covered with a light-shielding film 15. The row direction width W1 (or W4) of the light-shielding film 15 covering the light incident surface of the first specific photoelectric conversion unit 18 included in the same photoelectric conversion unit pair 17 is equal to the row direction width W3 (or W2) of the region of the light incident surface of the second specific photoelectric conversion unit 19 that is not covered with the light-shielding film 15. Also, when viewed from the thickness direction of the semiconductor substrate 1, the widths W1 and W4 of the light-shielding film 15 in the row direction are set to a size such that the light-collecting region X of the light L that passes through the camera lens 101 having a predetermined pupil distance (any of the first pupil distance EPD1, the second pupil distance EPD2, and the third pupil distance EPD3) and is collected by the microlens 14 overlaps with the end of the light-shielding film 15 in the row direction. That is, the widths W1 and W4 of the light-shielding film 15 are set to block half of the light-collecting region X and to pass the remaining half. As a result, the light that passes through one side of the exit pupil 55 of the camera lens 101 in the row direction is blocked, and the light that passes through the other side is allowed to pass. FIG. 19 illustrates a case in which the widths W1 and W4 of the upper light-shielding film 15 of the special pixels 5 of the first group 9 are adjusted to a width corresponding to the first pupil distance EPD1, and the widths W1 and W4 of the lower light-shielding film 15 are adjusted to a width corresponding to the second pupil distance EPD2. Although not shown, the widths of the light blocking films 15 in the second group 10 and the third group 11 (see FIG. 2) are also adjusted in the same manner.

[0038] With this arrangement of the light-shielding film 15, as shown in FIG. 19, when viewed from the thickness direction of the semiconductor substrate 1, the light-shielding film 15 includes a first light-shielding film 20 (the light-shielding film 15 located above the special pixels 5 in the second and fourth rows from the top in FIG. 19) whose row-wise widths W1, W4 are large enough to overlap the collection area X of light L that passes through a camera lens 101 having a first pupil distance EPD1 and is collected by the microlens 14 and the row-wise end of the light-shielding film 15, and a second light-shielding film 21 (the light-shielding film 15 located below the special pixels 5 in the second and fourth rows from the top in FIG. 19) whose row-wise widths W1, W4 are large enough to overlap the collection area X of light L that passes through a camera lens 101 having a second pupil distance EPD2 different from the first pupil distance EPD1 and is collected by the microlens 14 and the row-wise end of the light-shielding film 15. The multiple photoelectric conversion unit pairs 17 are configured to include a first specific photoelectric conversion unit pair 22 (a pair of specific photoelectric conversion units 16 located on the upper side of the special pixels 5 in the second and fourth rows from the top in Figure 19) in which the light shielding film 15 covering the light incident surfaces of the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 is the first light shielding film 20, and a second specific photoelectric conversion unit pair 23 (a pair of specific photoelectric conversion units 16 located on the lower side of the special pixels 5 in the second and fourth rows from the top in Figure 19) in which the light shielding film 15 covering the light incident surfaces of the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 is the second light shielding film 21.

[0039] 19, one of a pair of photoelectric conversion units (a pair of PD1 and PD2, a pair of PD3 and PD4) located on one side (upper side in FIG. 19) in the column direction of two specific special pixels 5 (special pixels 5 in the second and fourth rows from the top in FIG. 19) (upper side in FIG. 19) is the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 of the first specific photoelectric conversion unit pair 22. Also, in FIG. 19, one of a pair of photoelectric conversion units (lower photoelectric conversion unit PD3 or PD4 in FIG. 19) located on the other side (lower side in FIG. 19) in the column direction of the two specific special pixels 5 is the first specific photoelectric conversion unit 18 and the second specific photoelectric conversion unit 19 of the second specific photoelectric conversion unit pair 23. With the above-described configuration, the light receiving element 106 of this modified example has half the number of photoelectric conversion units used to generate phase difference signals compared to the light receiving element 106 of the second embodiment, and therefore the sensitivity is reduced to half, but the number of applicable pupil distances EPD can be doubled. In addition, in FIG. 19, as an example, the light-shielding film 15 has a rectangular shape when viewed in the thickness direction of the semiconductor substrate 1, but may have a trapezoidal shape as shown in FIG.

[0040] (4) In the second embodiment, an example is shown in which a phase difference signal is generated based on pixel signals of two specific photoelectric conversion units 16 (the specific photoelectric conversion unit 16 of the first pixel group 12 and the specific photoelectric conversion unit 16 of the second pixel group 13) constituting the photoelectric conversion unit pair 17, but other configurations can also be adopted. For example, as shown in FIG. 22, a configuration may be used in which only one specific photoelectric conversion unit 16 of the two specific photoelectric conversion units 16 constituting the photoelectric conversion unit pair 17 is included. FIG. 22 illustrates a case in which the specific photoelectric conversion unit 16 is omitted from the second pixel group 13 in the configuration of the pixel region 2 shown in FIG. 11, and the specific photoelectric conversion unit 16 is included only in the first pixel group 12. A photoelectric conversion unit without a light-shielding film 15 is disposed in the location where the specific photoelectric conversion unit 16 is omitted. That is, in FIG. 22, the configuration is such that the special pixel 5 of the second pixel group 13 is replaced with a normal pixel 4 in the configuration of the pixel region 2 shown in FIG. 11.

[0041] In this case, when adjusting the focus of the camera lens 101, the signal processing unit 107 generates a pixel signal by subtracting the pixel signals (hereinafter also referred to as the "second pixel signals") of two first specific photoelectric conversion units 18 (photoelectric conversion units PD2 and PD4 in FIG. 23) located on one side of the row direction of the special pixel 5 (right or left side in FIG. 22) and whose light incident surfaces are covered with a light-shielding film 15) from the pixel signals (hereinafter also referred to as the "first pixel signals") of two photoelectric conversion units (photoelectric conversion units PD2 and PD4 in FIG. 23) located on one side of the row direction of the replaced normal pixel 4 (right or left side in FIG. 22 and FIG. 23) and whose light incident surfaces are not covered with a light-shielding film 15, as shown in FIG. 22 and FIG. 23. As the two photoelectric conversion units of the normal pixel 4 used for subtraction, for example, the two photoelectric conversion units of the normal pixel 4 in Fig. 22 located at the location where the first specified photoelectric conversion unit 18 and the second specified photoelectric conversion unit 19 constituting the photoelectric conversion unit pair 17 in Fig. 11 are located can be used. For example, in Fig. 22, when the photoelectric conversion units PD2 and PD4 of the special pixel 5 in the second row from the top and the third row from the left are selected as the specified photoelectric conversion unit 16 to be used for subtraction, the photoelectric conversion units PD2 and PD4 of the normal pixel 4 in the first row from the bottom and the third row from the left in Fig. 22 are used as the photoelectric conversion unit of the normal pixel 4 to be used for subtraction. The pixel signal generated by the subtraction becomes a pixel signal obtained in the second specified photoelectric conversion unit 19 constituting the photoelectric conversion unit pair 17 with the first specified photoelectric conversion unit 18 in Fig. 11, as shown in Fig. 23. As a result, by using the pixel signal generated by the above subtraction instead of the pixel signal of the second specified photoelectric conversion unit 19 in the second embodiment, a phase difference signal can be generated similarly to the second embodiment. Fig. 23 is a diagram showing an image of subtraction between pixel signals performed by the signal processing unit 107.

[0042] (5) For example, as shown in FIG. 24, the specific photoelectric conversion unit 16 may be omitted from the second pixel group 13 in the pixel region 2 shown in FIG. 16. That is, in FIG. 24, the special pixel 5 in the second pixel group 13 is replaced with a normal pixel 4 in the pixel region 2 shown in FIG. 16. FIG. 24 illustrates an example in which the width pattern of the first light-shielding film 20 in the first pixel group 12 is replaced with the width pattern of the first light-shielding film 20 in the second pixel group 13. With this configuration, when a camera lens 101 having a basic pupil distance EPD0 is attached to the imaging device 100, the light-collecting region X is located at the center of the normal pixel 4 (i.e., between the photoelectric conversion units PD1 to PD4) as shown in FIG. 25, so that a phase difference signal can be generated by using the pixel signals of the four photoelectric conversion units PD1 to PD4 of the normal pixel 4. FIG. 25 is a diagram illustrating the normal pixels 4 at the center of the image height and at a high image height in FIG. 24. In addition, when a camera lens 101 having a first pupil distance EPD1 is attached to the imaging device 100, the light collecting region X is located on an end of the first light-shielding film 20 in the row direction as shown in Fig. 26, so that a phase difference signal can be generated by using pixel signals of two specific photoelectric conversion units 16 having the first light-shielding film 20 and pixel signals generated by the subtraction shown in Fig. 26. Similarly, when a camera lens 101 having a second pupil distance EPD2 is attached to the imaging device 100, the light collecting region X is located on an end of the second light-shielding film 21 in the row direction as shown in Fig. 27, so that a phase difference signal can be generated by using pixel signals of two specific photoelectric conversion units 16 having the second light-shielding film 21 and pixel signals generated by the subtraction shown in Fig. 26. Figs. 26 and 27 are diagrams showing special pixels 5 at the center of the image height and at high image heights extracted from Fig. 24.

[0043] Here, when the pixel region 2 shown in FIG. 24 is used and the signal processing unit 107 performs the subtraction shown in FIG. 26, the pixel signal obtained is as shown in the graph in FIG. 28. In the graph in FIG. 28, the horizontal axis indicates the incident angle of light L, and the vertical axis indicates a signal (normalized output) obtained by normalizing the pixel signal of the photoelectric conversion unit. In the graph in FIG. 28, as normalized outputs, pixel signals (hereinafter also referred to as "first pixel signals") of the photoelectric conversion units PD1 to PD4 of a pinhole pixel 40 (see FIG. 29) having a structure equivalent to the special pixel 5 shown in FIG. 24, pixel signals (hereinafter also referred to as "second pixel signals") of the photoelectric conversion units PD1 to PD4 of a normal pixel 4, and a pixel signal (hereinafter also referred to as "third pixel signal") obtained by subtracting the first pixel signal from the second pixel signal are shown. As shown in FIG. 29, the pinhole pixel 40 is a pixel having a pinhole light shielding film 41 that opens the center of the pixel 3 and shields the outer periphery from light. The first pixel signals output from the photoelectric conversion units PD1 to PD4 of the pinhole pixel 40 are pixel signals obtained when the light L passing through the outer periphery of the camera lens 101 is blocked, as shown in Fig. 30, and therefore have low separability. The third pixel signal is equivalent to the pixel signals of the photoelectric conversion units PD1 to PD4 of the island pixel 43 having the island light-shielding film 42 that shields the center of the pixel 3, as shown in Fig. 31. Therefore, the third pixel signal is a pixel signal obtained when the light L passing through the center of the camera lens 101 is blocked, as shown in Fig. 32, and therefore has high separability.

[0044] 28 includes a pixel signal with high separability (first pixel signal), a pixel signal with low separability (third pixel signal), and a pixel signal with intermediate separability (second pixel signal), and therefore three intersections (first intersection 44, second intersection 45, and third intersection 46) of the first to third pixel signals appear near a normalized output of 0.5. The first intersection 44 and the third intersection 46 are intersections between the pixel signal of the pinhole pixel 40 and the pixel signal of the island pixel 43. The second intersection 45 is an intersection between the pixel signal of the photoelectric conversion unit on the left side of the normal pixel 4 and the pixel signal of the photoelectric conversion unit on the right side. Therefore, by using a photodetector 106 having a pinhole pixel 40 (a photodetector 106 having a special pixel 5 shown in FIG. 24), when a camera lens 101 having an incidence angle corresponding to the three intersection points, that is, a camera lens 101 having a pupil distance EPD at which these incidence angles can be obtained, is attached to the imaging device 100, a highly accurate phase difference signal can be generated.

[0045] (6) In the second embodiment, the first pixel group 12 and the second pixel group 13 are formed of a plurality of special pixels 5 arranged in a row direction, but other configurations can be adopted. For example, as shown in FIG. 33, the first pixel group 12 and the second pixel group 13 may be formed of a plurality of special pixels 5 arranged in a column direction. FIG. 33 illustrates a case in which the second pixel group 13 is formed in the same column as the first pixel group 12, and the special pixels 5 of the first pixel group 12 and the special pixels 5 of the second pixel group 13 alternately appear. In this case, one pair of photoelectric conversion units out of two pairs of photoelectric conversion units (a pair of PD1 and PD2, and a pair of PD3 and PD4 in FIG. 33) arranged in the row direction included in the special pixel 5 is used as the specific photoelectric conversion unit 16. As a result, a phase difference signal can be generated similarly to the second embodiment by using the sum of the pixel signals of the pair of photoelectric conversion units instead of the pixel signal of the specific photoelectric conversion unit 16 of the second embodiment. For example, in the special pixel 5 in the second row from the top and the third row from the left in FIG.

[0046] The specific photoelectric conversion unit 16 is one of the specific photoelectric conversion units 16 of the special pixel 5 of the first pixel group 12 and the specific photoelectric conversion unit 16 of the special pixel 5 of the second pixel group 13. The two specific photoelectric conversion units 16 arranged in close positions (positions sandwiching a normal pixel 4 in FIG. 33) form a photoelectric conversion unit pair 17. The photoelectric conversion unit pair 17 includes two first specific photoelectric conversion units 18 located on one side (upper or lower in FIG. 33) of a special pixel 5 (special pixel 5 in the second row from the top and third row from the left, and special pixel 5 in the first row from the bottom and third row from the left in FIG. 33) in the column direction and having one end side region (upper region or lower region in FIG. 33) of the light incident surface covered with a light shielding film 15. It also includes two second specific photoelectric conversion units 19 that are located on one side (upper or lower in Figure 33) in the column direction of other special pixels 5 (special pixel 5 in the fourth row from the top and third row from the left in Figure 33, and special pixel 5 in the third row from the bottom and third row from the left in Figure 33) and whose other end region in the column direction of the light incident surface (lower region or upper region in Figure 33) is covered with a light-shielding film 15. Moreover, the width W1 (or W4) in the column direction of the light-shielding film 15 covering the light incident surface of the first specific photoelectric conversion unit 18 included in the same photoelectric conversion unit pair 17 is equal to the width W3 (or W2) in the column direction of the region of the light incident surface of the second specific photoelectric conversion unit 19 that is not covered by the light-shielding film 15. When viewed from the thickness direction of the semiconductor substrate 1, the widths W1 and W4 in the column direction of the light-shielding film 15 are large enough to overlap the light-collecting region X of the light L that passes through the camera lens 101 having a predetermined pupil distance (any of the first pupil distance EPD1, the second pupil distance EPD2, and the third pupil distance EPD3) and is collected by the microlens 14 with the end of the light-shielding film 15 in the column direction. That is, the widths W1 and W4 of the light-shielding film 15 are set to a width that blocks half of the light-collecting region X and passes the remaining half. 33 illustrates an example in which the widths W1 and W4 of the light-shielding films 15 of the special pixels 5 in the first group 9 are adjusted to a width corresponding to the first pupil distance EPD1. With this configuration, the light receiving element 106 according to this modification can acquire a vertical phase difference signal as a phase difference signal.

[0047] 34, in the normal pixel 4 of the modified example shown in FIG. 33, the deepest potential PDVmax and OF2, the deepest part of the potential of the second overflow path 36 Vmax and OF3, the deepest part of the potential of the third overflow path 37 Vmax and the deepest TG of the potential of the first overflow path 38 Vmax The relationship between the magnitude and PD Vmax >OF2 Vmax >OF3 Vmax >T.G. Vmax As a result, when the charge of any of the photoelectric conversion units PD1 to PD4 of the normal pixel 4 becomes saturated, the charge moves to the photoelectric conversion unit in the same row as the photoelectric conversion unit whose charge is saturated, and when the charge of the photoelectric conversion unit in the same row also becomes saturated, the charge moves to the photoelectric conversion unit in the same column as the photoelectric conversion unit whose charge is saturated, and when the charge of the photoelectric conversion unit in the same column also becomes saturated, the charge moves to the floating diffusion FD. PD Vmax , OF2 Vmax , OF3 Vmax and T.G. Vmax The magnitude relationship can be realized by adjusting the photoelectric conversion units PD1 to PD4, the p-well region pwell, the impurity concentrations of the impurity layer 30, and the like.

[0048] In addition, in Special Pixel 5, PD Vmax , OF2 Vmax , OF3 Vmax and T.G. Vmax The relationship between the magnitude of PD Vmax >OF2 Vmax >T.G. Vmax >OF3 VmaxIn other words, the potential of the second overflow path 36, which transfers electric charges between two photoelectric conversion units arranged in the row direction among the four photoelectric conversion units PD1 to PD4 included in the special pixel 5, is the deepest, the potential of the first overflow path 38, which transfers electric charges overflowing from the photoelectric conversion units PD to PD4 of the special pixel 5 to the floating diffusion FD, is the second deepest, and the potential of the third overflow path 37, which transfers electric charges between two photoelectric conversion units arranged in the column direction among the four photoelectric conversion units PD1 to PD4 included in the special pixel 5, is the third deepest. As a result, in the special pixel 5, when the electric charge of any of the photoelectric conversion units PD1 to PD4 becomes saturated, the electric charge moves to the photoelectric conversion unit in the same row as the photoelectric conversion unit in which the electric charge is saturated, and when the electric charge of the photoelectric conversion unit in the same row also becomes saturated, the electric charge moves to the floating diffusion FD. Therefore, it is possible to suppress the transfer of charges between a specific photoelectric conversion unit 16 and a photoelectric conversion unit in the same column as the specific photoelectric conversion unit 16, and to suppress a decrease in accuracy of the phase difference signal.

[0049] (7) For example, as shown in FIGS. 35 and 36, in addition to the structure of the special pixel 5 shown in FIG. 11, the special pixel 5 may further include second light-shielding films 50, 51 (broadly speaking, "second direction light-shielding films") covering one end side region or the other end side region (upper region or lower region in FIG. 35) in the column direction of the light incident surface of the specific photoelectric conversion unit 16. The second light-shielding films 50, 51 have the same structure as the first and second light-shielding films 20, 21 shown in FIG. 33. That is, when viewed from the thickness direction of the semiconductor substrate 1, the column direction width W1 (or W4) of the second light-shielding films 50, 51 is large enough that the light-collecting region X of the light L that passes through the camera lens 101 having a predetermined pupil distance (any of the first pupil distance EPD1, the second pupil distance EPD2, and the third pupil distance EPD3) and is collected by the microlens 14 overlaps with the column direction end of the second light-shielding film 50. At the portion where the light-shielding film 15 and the second light-shielding film 50 overlap, the light-shielding film 15 and the second light-shielding film 50 are integrated. In addition, in FIG. 35, the photoelectric conversion unit corresponding to the first specific photoelectric conversion unit 18 in FIG. 33 is indicated by reference numeral 52, and the photoelectric conversion unit corresponding to the second specific photoelectric conversion unit 19 is indicated by reference numeral 53. With such a configuration, the light-receiving element 106 according to this modification can acquire both a horizontal phase difference signal and a vertical phase difference signal as the phase difference signal, and can also accommodate a plurality of pupil distances EPD. FIG. 36 is an enlarged view of the upper left corner of the light-receiving element 106 shown in FIG. 35.

[0050] 37, in the normal pixel 4 of the modified example shown in FIG. 35, the deepest potential PD Vmax and OF2, the deepest part of the potential of the second overflow path 36 Vmax and OF3, the deepest part of the potential of the third overflow path 37 Vmax and the deepest TG of the potential of the first overflow path 38 Vmax The relationship between PD and Vmax >OF2 Vmax >OF3 Vmax >T.G. VmaxAs a result, when the charge of any of the photoelectric conversion units PD1 to PD4 of the normal pixel 4 becomes saturated, the charge moves to the photoelectric conversion unit in the same column as the photoelectric conversion unit whose charge is saturated, and when the charge of the photoelectric conversion unit in the same column also becomes saturated, the charge moves to the photoelectric conversion unit in the same row as the photoelectric conversion unit whose charge is saturated, and when the charge of the photoelectric conversion unit in the same row also becomes saturated, the charge moves to the floating diffusion FD. PD Vmax , OF2 Vmax , OF3 Vmax and T.G. Vmax The magnitude relationship between OF2 and OF3 can be achieved by adjusting the impurity concentrations of the photoelectric conversion units PD1 to PD4, the p-well region pwell, the impurity layer 30, and the like. Vmax , OF3 Vmax The order of the magnitude relationship is set according to whether the pixel signal of the photoelectric conversion units PD2 and PD4 (the photoelectric conversion units on the left side in FIG. 35) is acquired first, or the pixel signal of the photoelectric conversion units PD1 and PD2 (the photoelectric conversion units on the upper side in FIG. 35) is acquired first. OF2 Vmax >OF3 Vmax This is the order in the case where the pixel signals of the photoelectric conversion units PD2 and PD4 are acquired first.

[0051] In addition, in Special Pixel 5, PD Vmax , OF2 Vmax , OF3 Vmax and T.G. Vmax The relationship between the magnitude of PD Vmax >T.G. Vmax >OF2 Vmax , OF3 VmaxIn other words, the potential of the first overflow path 38 that transfers the charge overflowing from the photoelectric conversion units PD to PD4 of the special pixel 5 to the floating diffusion FD is deeper than the potential of the second overflow path 36 that transfers the charge between two photoelectric conversion units aligned in the column direction among the four photoelectric conversion units PD1 to PD4 included in the special pixel 5, and the potential of the third overflow path 37 that transfers the charge between two photoelectric conversion units aligned in the row direction. As a result, when the charge of any of the photoelectric conversion units PD1 to PD4 in the special pixel 5 becomes saturated, the charge moves to the floating diffusion FD. Therefore, the transfer of charge between the specific photoelectric conversion unit 16 and the photoelectric conversion unit in the same row or the photoelectric conversion unit in the same column as the specific photoelectric conversion unit 16 can be suppressed, and the deterioration of the accuracy of the phase difference signal can be suppressed.

[0052] (8) Furthermore, the present technology can be applied to photodetection devices in general, including distance measuring sensors that measure distance, also called ToF (Time of Flight) sensors, in addition to the light receiving element 106 as the image sensor described above. A distance measuring sensor is a sensor that emits irradiation light toward an object, detects the reflected light that is reflected by the surface of the object, and calculates the distance to the object based on the flight time from when the irradiation light is emitted to when the reflected light is received. The structure of pixel 3 described above can be adopted as the light receiving pixel structure of this distance measuring sensor.

[0053] The present technology can also be configured as follows. (1) A semiconductor substrate including a plurality of photoelectric conversion units arranged in an array in a first direction and a second direction; A plurality of pixels including two or more of the photoelectric conversion units arranged in the first direction; a microlens disposed on a light incident surface side of the semiconductor substrate and configured to condense light that has passed through an imaging optical system of the imaging device for each pixel; The plurality of pixels includes a plurality of special pixels; The special pixel has a light-shielding film that covers one end side region or the other end side region in the first direction of a light incident surface of a specific photoelectric conversion unit that is at least a part of the two or more photoelectric conversion units, At least some of the special pixels among the plurality of special pixels are arranged apart from each other in the first direction, and the width of the light-shielding film of each of the special pixels in the first direction differs depending on the image height in the first direction of the specific photoelectric conversion unit covered by the light-shielding film. Light detection device. (2) When viewed from the thickness direction of the semiconductor substrate, the width of the light-shielding film in the first direction is set to a size such that a light-collecting area of ​​light that has passed through the imaging optical system having a predetermined pupil distance and has been collected by the microlens overlaps with an end portion of the light-shielding film in the first direction. The light detection device according to (1) above. (3) The pixel includes, as the two or more photoelectric conversion units, two of the photoelectric conversion units arranged in the first direction, The specific photoelectric conversion unit is one of the two photoelectric conversion units included in the special pixel. The light detection device according to (1) above. (4) The specific photoelectric conversion unit is configured to include a plurality of photoelectric conversion unit pairs, each of which includes a first specific photoelectric conversion unit located on one side of one of the special pixels in the first direction and having one end region of a light incident surface in the first direction covered with the light-shielding film, and a second specific photoelectric conversion unit located on one side of another of the special pixels in the first direction and having the other end region of a light incident surface in the first direction covered with the light-shielding film; The width in the first direction of the light-shielding film covering the light incident surface of the first specific photoelectric conversion unit included in the same photoelectric conversion unit pair is equal to the width in the first direction of a region of the light incident surface of the second specific photoelectric conversion unit that is not covered by the light-shielding film. The optical detection device according to (3) above. (5) when viewed from a thickness direction of the semiconductor substrate, the light-shielding film includes: a first light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a predetermined first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; and a second light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a second pupil distance different from the first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; The plurality of photoelectric conversion unit pairs include a first specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the first light-shielding film, and a second specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the second light-shielding film. The light detection device according to (4) above. (6) The first specific photoelectric conversion unit pair and the second specific photoelectric conversion unit pair are the first specific photoelectric conversion unit and the second specific photoelectric conversion unit of the first specific photoelectric conversion unit pair, respectively, of the photoelectric conversion units located on one side of the first direction of two specific special pixels, and the first specific photoelectric conversion unit and the second specific photoelectric conversion unit of the second specific photoelectric conversion unit pair, respectively, of the photoelectric conversion units located on the other side of the two special pixels in the first direction. The optical detection device according to (5) above. (7) a first overflow path for transferring charges between the two photoelectric conversion units included in the special pixel; a second overflow path that transfers the charge overflowing from the photoelectric conversion unit of the special pixel to a floating diffusion; The potential of the second overflow path is deeper than the potential of the first overflow path. The optical detection device according to any one of (3) to (6). (8) The pixel includes, as the two or more photoelectric conversion units, four of the photoelectric conversion units arranged in a 2×2 array, The specific photoelectric conversion unit is one of two pairs of the photoelectric conversion units arranged in the second direction and included in the special pixel. The light detection device according to (1) above. (9) The specific photoelectric conversion unit is configured to include a plurality of photoelectric conversion unit pairs, each of which includes two first specific photoelectric conversion units located on one side of one of the special pixels in the first direction and having one end side region of a light incident surface in the first direction covered with the light-shielding film, and two second specific photoelectric conversion units located on one side of another of the special pixels in the first direction and having the other end side region of a light incident surface in the first direction covered with the light-shielding film; The width in the first direction of the light-shielding film covering the light incident surface of the first specific photoelectric conversion unit included in the same photoelectric conversion unit pair is equal to the width in the first direction of a region of the light incident surface of the second specific photoelectric conversion unit that is not covered by the light-shielding film. The photodetector according to (8) above. (10) when viewed from a thickness direction of the semiconductor substrate, the light-shielding film includes: a first light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a predetermined first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; and a second light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a second pupil distance different from the first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; The plurality of photoelectric conversion unit pairs include a first specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the first light-shielding film, and a second specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the second light-shielding film. The light detection device according to (9) above. (11) The first specific photoelectric conversion unit pair and the second specific photoelectric conversion unit pair are each a pair of the photoelectric conversion units located on one side of two specific special pixels in the first direction, and each a pair of the photoelectric conversion units located on the other side of the two special pixels in the first direction, and each a pair of the photoelectric conversion units located on the other side of the two special pixels in the first direction, and each a pair of the photoelectric conversion units located on the other side of the two special pixels in the first direction, and each a pair of the photoelectric conversion units located on the other side of the two special pixels in the first direction. The optical detection device according to (10) above. (12) a signal processing unit that generates a pixel signal by subtracting a second pixel signal, which is a pixel signal of two of the specific photoelectric conversion units that are located on one side of the special pixel in the first direction and whose light incident surfaces are covered with the light shielding film, from a first pixel signal, which is a pixel signal of two of the photoelectric conversion units that are located on one side of the pixel in the first direction and whose light incident surfaces are not covered with the light shielding film. The photodetector according to (8) above. (13) a first overflow path that transfers charge overflowing from the photoelectric conversion unit of the special pixel to a floating diffusion; a second overflow path that transfers electric charges between two of the photoelectric conversion units arranged in the second direction among the four photoelectric conversion units included in the special pixel; a third overflow path for transferring charges between two of the photoelectric conversion units arranged in the first direction among the four photoelectric conversion units included in the special pixel, The second overflow path has the deepest potential, the first overflow path has the second deepest potential, and the third overflow path has the third deepest potential. The photodetector according to any one of (8) to (12) above. (14) The pixel includes, as the two or more photoelectric conversion units, four of the photoelectric conversion units arranged in a 2×2 array, The specific photoelectric conversion unit is one of the four photoelectric conversion units included in the special pixel. The light detection device according to (1) above. (15) The specific photoelectric conversion unit is configured to include a plurality of photoelectric conversion unit pairs, each of which includes a first specific photoelectric conversion unit located on one side of one of the special pixels in the first direction and having one end region of a light incident surface in the first direction covered with the light-shielding film, and a second specific photoelectric conversion unit located on one side of another of the special pixels in the first direction and having the other end region of a light incident surface in the first direction covered with the light-shielding film; The width in the first direction of the light-shielding film covering the light incident surface of the first specific photoelectric conversion unit included in the same photoelectric conversion unit pair is equal to the width in the first direction of a region of the light incident surface of the second specific photoelectric conversion unit that is not covered by the light-shielding film. The optical detection device according to (14) above. (16) when viewed from a thickness direction of the semiconductor substrate, the light-shielding film includes: a first light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a predetermined first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; and a second light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a second pupil distance different from the first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; The plurality of photoelectric conversion unit pairs include a first specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the first light-shielding film, and a second specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the second light-shielding film. The optical detection device according to (15) above. (17) The first specific photoelectric conversion unit pair and the second specific photoelectric conversion unit pair are each one of a pair of the photoelectric conversion units located on one side of the second direction of two specific pixels, and each one of the pair of the photoelectric conversion units located on the other side of the two special pixels in the second direction is each one of the first specific photoelectric conversion unit pair and the second specific photoelectric conversion unit of the second specific photoelectric conversion unit pair. The optical detection device according to (16) above. (18) When viewed from the thickness direction of the semiconductor substrate, the light-shielding film has a rectangular or trapezoidal shape. The photodetector according to any one of (14) to (17) above. (19) The pixel includes, as the two or more photoelectric conversion units, four of the photoelectric conversion units arranged in a 2×2 array, The special pixel further includes a second direction light-shielding film that covers one end side region or the other end side region of the light incident surface of the specific photoelectric conversion unit in the second direction. The light detection device according to (1) above. (20) When viewed from the thickness direction of the semiconductor substrate, the width of the second direction light-shielding film in the second direction is set to a size such that a light-collecting area of ​​light that has passed through the imaging optical system having a predetermined pupil distance and has been collected by the microlens overlaps with an end portion of the light-shielding film in the second direction. The light detection device according to (19) above. (twenty one) a first overflow path that transfers charge overflowing from the photoelectric conversion unit of the special pixel to a floating diffusion; a second overflow path that transfers electric charges between two of the photoelectric conversion units arranged in the second direction among the four photoelectric conversion units included in the special pixel; a third overflow path for mutually transferring charges between two of the photoelectric conversion units arranged in the first direction among the four photoelectric conversion units included in the special pixel, The potential of the first overflow path is deeper than the potential of the second overflow path and the third overflow path. The optical detection device according to (19) or (20) above. (twenty two) When viewed from the thickness direction of the semiconductor substrate, the microlens is disposed at a pupil-corrected position such that a light collection area of ​​light that passes through the imaging optical system having a predetermined pupil distance and is collected by the microlens overlaps with the center of the pixel. The photodetector according to any one of (1) to (21) above. (twenty three) a semiconductor substrate including a plurality of photoelectric conversion units arranged in an array in a first direction and a second direction; a plurality of pixels including two or more of the photoelectric conversion units arranged in the first direction; and a microlens arranged on a light incident surface side of the semiconductor substrate and configured to collect light that has passed through an imaging optical system of an imaging device for each pixel, the plurality of pixels including a plurality of special pixels, each of the special pixels having a light shielding film that covers one end side region or the other end side region in the first direction of the light incident surface of a specific photoelectric conversion unit that is at least a part of the two or more photoelectric conversion units, at least a part of the plurality of special pixels being arranged apart from each other in the first direction, and a light detection device in which the width in the first direction of the light shielding film of each of the special pixels differs depending on an image height in the first direction of the specific photoelectric conversion unit that is covered by the light shielding film Imaging device. [Explanation of symbols]

[0054] 1...semiconductor substrate, 2...pixel region, 3...pixel, 4...normal pixel, 5...special pixel, 6...first block, 7...second block, 8...block pair, 9...first group, 10...second group, 11...third group, 12...first pixel group, 13...second pixel group, 14...microlens, 15...light-shielding film, 16...specific photoelectric conversion unit, 17...photoelectric conversion unit pair, 18...first specific photoelectric conversion unit, 19...second specific photoelectric conversion unit, 20...first light-shielding film, 21...second light-shielding film, 22...first specific photoelectric conversion unit pair, 23...second specific photoelectric conversion unit pair, 24...pixel separation structure, 25...inter-pixel separation unit, 26...intra-pixel separation unit, 27...trench portion, 28...fixed charge film, 29...insulating film, 30...impurity layer, 31...first overflow Low pass, 32...transfer transistor, 33...gate insulating film, 34...gate electrode, 35...second overflow path, 36...second overflow path, 37...third overflow path, 38...first overflow path, 40...pinhole pixel, 41...pinhole light-shielding film, 42...island light-shielding film, 43...island pixel, 44...first intersection, 45...second intersection, 46...third intersection, 50...second light-shielding film, 51...second light-shielding film, 52...first specific photoelectric conversion unit, 53...second specific photoelectric conversion unit, 54...color filter, 55...exit pupil, 100...imaging device, 101...camera lens, 102...solid-state imaging device, 103...control unit, 104...storage unit, 105...monitor, 106...light-receiving element, 107...signal processing unit

Claims

1. a semiconductor substrate including a plurality of photoelectric conversion units arranged in an array in a first direction and a second direction; A plurality of pixels including two or more of the photoelectric conversion units arranged in the first direction; a microlens disposed on a light incident surface side of the semiconductor substrate and configured to condense light that has passed through an imaging optical system of the imaging device for each pixel; The plurality of pixels includes a plurality of special pixels; The special pixel has a light-shielding film that covers one end side region or the other end side region in the first direction of a light incident surface of a specific photoelectric conversion unit that is at least a part of the two or more photoelectric conversion units, At least some of the special pixels among the plurality of special pixels are arranged apart from each other in the first direction, and the width of the light-shielding film of each of the special pixels in the first direction differs depending on the image height in the first direction of the specific photoelectric conversion unit covered by the light-shielding film. Light detection device.

2. When viewed from the thickness direction of the semiconductor substrate, the width of the light-shielding film in the first direction is set to a size such that a light-collecting area of ​​light that has passed through the imaging optical system having a predetermined pupil distance and has been collected by the microlens overlaps with an end portion of the light-shielding film in the first direction.

2. The optical detection device according to claim 1.

3. The pixel includes, as the two or more photoelectric conversion units, two of the photoelectric conversion units arranged in the first direction, The specific photoelectric conversion unit is one of the two photoelectric conversion units included in the special pixel.

2. The optical detection device according to claim 1.

4. The specific photoelectric conversion unit is configured to include a first specific photoelectric conversion unit located on one side of one of the special pixels in the first direction and having one end region of a light incident surface in the first direction covered with the light-shielding film, and a second specific photoelectric conversion unit located on one side of another of the special pixels in the first direction and having the other end region of a light incident surface in the first direction covered with the light-shielding film, The width in the first direction of the light-shielding film covering the light incident surface of the first specific photoelectric conversion unit included in the same photoelectric conversion unit pair is equal to the width in the first direction of a region of the light incident surface of the second specific photoelectric conversion unit that is not covered by the light-shielding film.

4. The optical detection device according to claim 3.

5. when viewed from a thickness direction of the semiconductor substrate, the light-shielding film includes: a first light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a predetermined first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; and a second light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a second pupil distance different from the first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; The plurality of photoelectric conversion unit pairs include a first specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the first light-shielding film, and a second specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the second light-shielding film.

5. The optical detection device according to claim 4.

6. The first specific photoelectric conversion unit pair and the second specific photoelectric conversion unit pair are the first specific photoelectric conversion unit and the second specific photoelectric conversion unit of the first specific photoelectric conversion unit pair, respectively, of the photoelectric conversion units located on one side of the first direction of two specific special pixels, and the first specific photoelectric conversion unit and the second specific photoelectric conversion unit of the second specific photoelectric conversion unit pair, respectively, of the photoelectric conversion units located on the other side of the two special pixels in the first direction.

6. The optical detection device according to claim 5.

7. a first overflow path for transferring charges between the two photoelectric conversion units included in the special pixel; a second overflow path that transfers the charge overflowing from the photoelectric conversion unit of the special pixel to a floating diffusion; The potential of the second overflow path is deeper than the potential of the first overflow path.

4. The optical detection device according to claim 3.

8. The pixel includes, as the two or more photoelectric conversion units, four of the photoelectric conversion units arranged in a 2×2 array, The specific photoelectric conversion unit is a pair of the photoelectric conversion units among two pairs of the photoelectric conversion units arranged in the second direction included in the special pixel.

2. The optical detection device according to claim 1.

9. The specific photoelectric conversion unit is configured to include a plurality of photoelectric conversion unit pairs, each of which includes two first specific photoelectric conversion units located on one side of one of the special pixels in the first direction and having one end side region of a light incident surface in the first direction covered with the light-shielding film, and two second specific photoelectric conversion units located on one side of another of the special pixels in the first direction and having the other end side region of a light incident surface in the first direction covered with the light-shielding film; The width in the first direction of the light-shielding film covering the light incident surface of the first specific photoelectric conversion unit included in the same photoelectric conversion unit pair is equal to the width in the first direction of a region of the light incident surface of the second specific photoelectric conversion unit that is not covered by the light-shielding film.

9. The optical detection device according to claim 8.

10. when viewed from a thickness direction of the semiconductor substrate, the light-shielding film includes: a first light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a predetermined first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; and a second light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a second pupil distance different from the first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; The plurality of photoelectric conversion unit pairs include a first specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the first light-shielding film, and a second specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the second light-shielding film.

10. The optical detection device according to claim 9.

11. The first specific photoelectric conversion unit pair and the second specific photoelectric conversion unit pair are each a pair of the photoelectric conversion units located on one side of two specific special pixels in the first direction, and are the first specific photoelectric conversion unit and the second specific photoelectric conversion unit of the first specific photoelectric conversion unit pair, and are each a pair of the photoelectric conversion units located on the other side of the two special pixels in the first direction, and are the first specific photoelectric conversion unit and the second specific photoelectric conversion unit of the second specific photoelectric conversion unit pair. The optical detection device according to claim 10.

12. a signal processing unit that generates a pixel signal by subtracting a second pixel signal, which is a pixel signal of two of the specific photoelectric conversion units that are located on one side of the special pixel in the first direction and whose light incident surfaces are covered with the light shielding film, from a first pixel signal, which is a pixel signal of two of the photoelectric conversion units that are located on one side of the pixel in the first direction and whose light incident surfaces are not covered with the light shielding film.

9. The optical detection device according to claim 8.

13. a first overflow path that transfers charge overflowing from the photoelectric conversion unit of the special pixel to a floating diffusion; a second overflow path that transfers electric charges between two of the four photoelectric conversion units included in the special pixel that are arranged in the second direction; and a third overflow path for transferring charges between two of the photoelectric conversion units arranged in the first direction among the four photoelectric conversion units included in the special pixel, The second overflow path has the deepest potential, the first overflow path has the second deepest potential, and the third overflow path has the third deepest potential.

9. The optical detection device according to claim 8.

14. The pixel includes, as the two or more photoelectric conversion units, four of the photoelectric conversion units arranged in a 2×2 array, The specific photoelectric conversion unit is one of the four photoelectric conversion units included in the special pixel.

2. The optical detection device according to claim 1.

15. The specific photoelectric conversion unit is configured to include a first specific photoelectric conversion unit located on one side of one of the special pixels in the first direction and having one end region of a light incident surface in the first direction covered with the light-shielding film, and a second specific photoelectric conversion unit located on one side of another of the special pixels in the first direction and having the other end region of a light incident surface in the first direction covered with the light-shielding film, The width in the first direction of the light-shielding film covering the light incident surface of the first specific photoelectric conversion unit included in the same photoelectric conversion unit pair is equal to the width in the first direction of a region of the light incident surface of the second specific photoelectric conversion unit that is not covered by the light-shielding film.

15. The optical detection device of claim 14.

16. when viewed from a thickness direction of the semiconductor substrate, the light-shielding film includes: a first light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a predetermined first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; and a second light-shielding film having a width in the first direction that is large enough to allow a collection area of ​​light that passes through the imaging optical system having a second pupil distance different from the first pupil distance and is collected by the microlens to overlap with an end portion of the light-shielding film in the first direction; The plurality of photoelectric conversion unit pairs include a first specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the first light-shielding film, and a second specific photoelectric conversion unit pair in which the light-shielding film covering the light incidence surfaces of the first specific photoelectric conversion unit and the second specific photoelectric conversion unit is the second light-shielding film.

16. The optical detection device of claim 15.

17. The first specific photoelectric conversion unit pair and the second specific photoelectric conversion unit pair are each one of a pair of the photoelectric conversion units located on one side of the second direction of two specific pixels, and each one of the pair of the photoelectric conversion units located on the other side of the two special pixels in the second direction is each one of the first specific photoelectric conversion unit pair and the second specific photoelectric conversion unit of the second specific photoelectric conversion unit pair.

17. The optical detection device of claim 16.

18. When viewed from the thickness direction of the semiconductor substrate, the light-shielding film has a rectangular or trapezoidal shape.

15. The optical detection device of claim 14.

19. The pixel includes, as the two or more photoelectric conversion units, four of the photoelectric conversion units arranged in a 2×2 array, The special pixel further includes a second direction light-shielding film that covers one end side region or the other end side region of the light incident surface of the specific photoelectric conversion unit in the second direction.

2. The optical detection device according to claim 1.

20. When viewed from the thickness direction of the semiconductor substrate, the width of the second direction light-shielding film in the second direction is set to a size such that a light-collecting area of ​​light that has passed through the imaging optical system having a predetermined pupil distance and has been collected by the microlens overlaps with an end portion of the second direction light-shielding film in the second direction.

20. The optical detection device of claim 19.

21. a first overflow path that transfers charge overflowing from the photoelectric conversion unit of the special pixel to a floating diffusion; a second overflow path that transfers electric charges between two of the four photoelectric conversion units included in the special pixel that are arranged in the second direction; and a third overflow path for transferring charges between two of the photoelectric conversion units arranged in the first direction among the four photoelectric conversion units included in the special pixel, The potential of the first overflow path is deeper than the potential of the second overflow path and the third overflow path.

20. The optical detection device of claim 19.

22. When viewed from the thickness direction of the semiconductor substrate, the microlens is disposed at a pupil-corrected position such that a light collection area of ​​light that passes through the imaging optical system having a predetermined pupil distance and is collected by the microlens overlaps with the center of the pixel.

2. The optical detection device according to claim 1.

23. a semiconductor substrate including a plurality of photoelectric conversion units arranged in an array in a first direction and a second direction; a plurality of pixels including two or more of the photoelectric conversion units arranged in the first direction; and a microlens arranged on a light incident surface side of the semiconductor substrate and configured to collect light that has passed through an imaging optical system of the imaging device for each pixel, the plurality of pixels including a plurality of special pixels, each of the special pixels having a light shielding film that covers one end side region or the other end side region in the first direction of the light incident surface of a specific photoelectric conversion unit that is at least a part of the two or more photoelectric conversion units, at least a part of the plurality of special pixels being arranged apart from each other in the first direction, and a light detection device in which the width in the first direction of the light shielding film of each of the special pixels differs depending on an image height in the first direction of the specific photoelectric conversion unit that is covered by the light shielding film Imaging device.

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