Photoelectric conversion device, and apparatus

Abstract

To prevent a reduction in sensitivity in a photoelectric conversion device.SOLUTION: A photoelectric conversion device has a plurality of pixels arranged in array. The plurality of pixels each have a microlens, a first photoelectric conversion element, a second photoelectric conversion element, a third photoelectric conversion element, and a fourth photoelectric conversion element arranged on two rows and two columns to receive light through the microlens, a first separation part, a second separation part, a third separation part, and a fourth separation part. The first separation part, the third separation part, and a first opening are arranged side by side in a first direction. The second separation part, the fourth separation part, and a second opening are arranged side by side in a second direction. The plurality of pixels have a first pixel and a second pixel separated in the first direction, and the first pixel is closer to the center of an array comprising the plurality of pixels than the second pixel. The arrangement of the first opening in the first pixel is different from the arrangement of the first opening in the second pixel.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a photoelectric conversion device and an apparatus. [Background technology]

[0002] There is known a photoelectric conversion device in which a plurality of pixels, each having a plurality of photoelectric conversion elements and a floating diffusion region shared by the plurality of photoelectric conversion elements, are arranged side by side. For example, Patent Document 1 discloses that one pixel includes four photoelectric conversion elements arranged in two rows and two columns, and a floating diffusion region disposed between the four photoelectric conversion elements, and an isolation region having a trench structure is disposed between the photoelectric conversion elements in the pixel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2016 / 0056200 Summary of the Invention [Problem to be solved by the invention]

[0004] When pixels in a pixel array are uniformly formed, there is a possibility that a decrease in sensitivity may occur in pixels where light is difficult to focus at the center of the pixel, such as pixels arranged at the edge of the pixel array. The present invention has been made in view of the above problem, and provides a photoelectric conversion device that can suppress the occurrence of a decrease in sensitivity in pixels where light is difficult to focus at the center of the pixel array. [Means for solving the problem]

[0005] One aspect of the present invention is a photoelectric conversion device having a plurality of pixels arranged in an array, wherein each of the plurality of pixels includes a microlens, a first photoelectric conversion element, a second photoelectric conversion element, a third photoelectric conversion element, and a fourth photoelectric conversion element arranged in two rows and two columns so as to receive light through the microlens, a first isolation portion provided between the first photoelectric conversion element and the second photoelectric conversion element, a second isolation portion provided between the first photoelectric conversion element and the third photoelectric conversion element, a third isolation portion provided between the third photoelectric conversion element and the fourth photoelectric conversion element, and a second isolation portion provided between the second photoelectric conversion element and the fourth photoelectric conversion element. a fourth isolation region separated from the first isolation region by a second isolation region, wherein the first isolation region, the third isolation region, and a first opening region provided between the first isolation region and the third isolation region are aligned in a first direction, and the second isolation region, the fourth isolation region, and a second opening region provided between the second isolation region and the fourth isolation region are aligned in a second direction, the plurality of pixels include a first pixel and a second pixel spaced apart in the first direction, the first pixel is closer to a center of the array of the plurality of pixels than the second pixel, and an arrangement of the first opening region in the first pixel is different from an arrangement of the first opening region in the second pixel. [Effects of the Invention]

[0006] According to the present invention, it is possible to suppress a decrease in pixel sensitivity. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a block diagram of a photoelectric conversion device according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram of a pixel according to the embodiment. [Figure 3] FIG. 1 is a schematic diagram of a pixel according to a first embodiment. [Figure 4] FIG. 10 is a schematic diagram of a pixel according to a second embodiment. [Figure 5] FIG. 10 is a schematic diagram of a pixel according to a third embodiment. [Figure 6] FIG. 10 is a schematic diagram of a pixel according to a fourth embodiment. [Figure 7] FIG. 10 is a schematic diagram of a pixel according to a fifth embodiment. [Figure 8] FIG. 10 is a schematic diagram of a pixel according to a fifth embodiment. [Figure 9] FIG. 10 is a schematic diagram illustrating a device according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] The configuration of each embodiment will be described with reference to the drawings. In each embodiment described below, an imaging device will be mainly described as an example of a photoelectric conversion device. However, each embodiment is not limited to an imaging device, and can also be applied to other examples of photoelectric conversion devices. For example, a distance measuring device (a device that measures distance using focus detection or TOF (Time Of Flight)) or a photometric device (a device that measures the amount of incident light) can be used.

[0009] Furthermore, the conductivity types of the semiconductor regions and wells and the dopants to be implanted described in the following embodiments are merely examples and are not limited to the conductivity types and dopants described in the embodiments. The conductivity types and dopants described in the embodiments can be changed as appropriate, and the potentials of the semiconductor regions and wells will be changed as appropriate in accordance with this change.

[0010] The conductivity types of the transistors described in the following embodiments are merely examples and are not limited to those described in the examples. The conductivity types described in the embodiments can be changed as appropriate, and the potentials of the gate, source, and drain of the transistors can be changed as appropriate.

[0011] For example, in the case of a transistor operated as a switch, the low and high levels of the potential supplied to the gate may be reversed in accordance with the change in the conductivity type. The conductivity types of the semiconductor regions described in the following examples are merely examples and are not limited to the conductivity types described in the examples. The conductivity types described in the examples can be changed as appropriate, and the potential of the semiconductor regions is accordingly changed accordingly.

[0012] In the following embodiments, the connection between elements of a circuit may be described. In this case, even if another element is interposed between the elements of interest, the elements of interest are treated as being connected to each other unless otherwise specified. For example, assume that element A is connected to one node of a capacitive element C having multiple nodes, and element B is connected to the other node. Even in such a case, element A and element B are treated as being connected to each other unless otherwise specified.

[0013] Metallic components such as wiring and pads described herein may be composed of a single metal element or a mixture (alloy). For example, wiring described as copper wiring may be composed of copper alone or may be composed primarily of copper with other components. Furthermore, for example, pads connected to external terminals may be composed of aluminum alone or may be composed primarily of aluminum with other components. The copper wiring and aluminum pads shown here are merely examples and can be replaced with various metals.

[0014] Furthermore, the wiring and pads shown here are examples of metal members used in photoelectric conversion devices, and the present invention can also be applied to other metal members.

[0015] (First embodiment) A photoelectric conversion device according to a first embodiment will be described with reference to FIGS. 1 to 3. FIG.

[0016] 1 is a schematic diagram showing the configuration of a photoelectric conversion device 100 according to this embodiment. The photoelectric conversion device 100 in FIG. 1 includes a pixel array 101, a vertical scanning circuit 102, a column amplifier circuit 103, a horizontal scanning circuit 104, an output circuit 105, a control circuit 106, and column signal lines 108.

[0017] The pixel array 101 has a plurality of pixels 107 arranged in a matrix across a plurality of rows and a plurality of columns. A control signal line is arranged in each row of the pixel array 101, extending in the row direction (horizontal direction in FIG. 1). The control signal line is connected to each of the pixels 107 arranged in the row direction and serves as a signal line common to these pixels 107. Furthermore, a column signal line 108 is arranged in each column of the pixel array 101, extending in the column direction (vertical direction in FIG. 1). The column signal line 108 is connected to each of the pixels 107 arranged in the column direction and serves as a signal line common to these pixels 107. Although one column signal line is depicted in FIG. 1, a plurality of column signal lines may be connected depending on the number of bits of the output signal.

[0018] There is no particular limitation on the number of pixels 107 that make up the pixel array 101. For example, the pixel array 101 may be made up of several thousand rows and several thousand columns of pixels 107, as in a typical digital camera, or may be made up of a plurality of pixels 107 arranged in one row or one column. Alternatively, the pixel array 101 may be made up of a single pixel 107.

[0019] The control signal lines of each row are connected to a vertical scanning circuit 102. The vertical scanning circuit 102 is a circuit section that supplies control signals to the pixels 107 via the control signal lines to drive readout circuits in the pixels 107 when pixel signals are read out from the pixels 107.

[0020] One end of the column signal line 108 of each column is connected to the column amplifier circuit 103. The pixel signals read out from the pixels 107 are input to the column amplifier circuit 103 via the column signal line 108. The column amplifier circuit 103 may include a memory or the like that holds the pixel signals read out from the pixels 107.

[0021] The horizontal scanning circuit 104 is a circuit section that supplies the column amplifier circuit 103 with control signals for sequentially transferring the pixel signals held in the column amplifier circuit 103 to the output circuit 105 for each column. The control circuit 106 is a circuit section that supplies control signals for controlling the operations and timing of the vertical scanning circuit 102, the column amplifier circuit 103, and the horizontal scanning circuit 104.

[0022] Figure 2 is a schematic diagram showing the configuration of a pixel 107. Figure 2(a) is a plan view of the pixel as seen from the front side of the semiconductor substrate, and Figure 2(b) is a plan view of the pixel 107 as seen from the back side of the semiconductor substrate. Figure 2(c) is a cross-section of the pixel 107 taken along the line AA' in Figure 2(b).

[0023] The pixel 107 includes four photoelectric conversion elements: a first photoelectric conversion element 201, a second photoelectric conversion element 202, a third photoelectric conversion element 203, and a fourth photoelectric conversion element 204, arranged in two rows and two columns. As shown in FIGS. 2(b) and 2(c), a microlens 230 is provided on the light incident surface of each of the four photoelectric conversion elements, and light enters each photoelectric conversion element through the microlens 230. A color filter 240 or an inner lens (not shown) may be further provided below the microlens 230. In FIG. 2(a), each photoelectric conversion element is provided with a transfer transistor. The first photoelectric conversion element 201 has a first transfer transistor 211, and the second photoelectric conversion element 202 has a second transfer transistor 212. Similarly, the third photoelectric conversion element 203 has a third transfer transistor 213, and the fourth photoelectric conversion element 204 has a fourth transfer transistor 214. The number and positions of the transfer transistors are not limited to this, and for example, two photoelectric conversion elements may share one transfer transistor.

[0024] The four sides of the periphery of the pixel 107 are surrounded by inter-pixel isolation portions 225, and adjacent pixels 107 are isolated from each other. Isolation portions are provided between the photoelectric conversion elements. A first isolation portion 221 is provided between the first photoelectric conversion element 201 and the second photoelectric conversion element 202, and a second isolation portion 222 is provided between the first photoelectric conversion element 201 and the third photoelectric conversion element 203. A third isolation portion 223 is provided between the third photoelectric conversion element 203 and the fourth photoelectric conversion element 204, and a fourth isolation portion 224 is provided between the second photoelectric conversion element and the fourth photoelectric conversion element 204. Each of the first isolation portion 221, the second isolation portion 221, the third isolation portion 223, and the fourth isolation portion 224 is provided perpendicular to at least one of the four sides of the inter-pixel isolation portion 225 in a plan view. In this description, each separation portion is in contact with or formed integrally with the inter-pixel separation portion 225. As long as each separation portion is provided so as to intersect with each side of the inter-pixel separation portion 225, it is not essential that the separation portion be in contact with each side of the inter-pixel separation portion 225.

[0025] Here, a first opening is formed between first separation portion 221 and third separation portion 223, and a second opening is formed between second separation portion 222 and fourth separation portion 224. First separation portion 221, third separation portion 223, and the first opening are aligned in a first direction, and second separation portion 222, fourth separation portion 224, and the second opening are aligned in a second direction.

[0026] Each of the inter-pixel isolation portion 225, the first isolation portion 221, the second isolation portion 221, the third isolation portion 223, and the fourth isolation portion 224 is, for example, a deep trench isolation (DTI). The area where the DTI is formed is not sensitive to light. Therefore, when light passing through the microlens 230 is focused on the DTI, the efficiency of the amount of charge generated relative to the amount of incident light decreases, which may result in a decrease in sensitivity. As shown in FIG. 2, areas (openings) where no DTI is formed are provided between the first isolation portion 221 and the third isolation portion 223 and between the second isolation portion 222 and the fourth isolation portion 224. This can prevent a decrease in sensitivity compared to when the isolation portion 221 and the isolation portion 223 are connected and the isolation portion 222 and the isolation portion 224 are connected.

[0027] In a sensor in which pixels are arranged in an array, when an image is formed by a lens and captured at the central and peripheral portions of the sensor, light is focused at the center of the central pixels (pixels in the lower image height area), but the amount of light incident on the DTI increases at the peripheral pixels (pixels in the higher image height area) without being focused at the pixel center. This results in a reduction in sensitivity at the peripheral portion of the sensor. Therefore, by appropriately positioning the DTI and aperture according to the image height, it is possible to eliminate or minimize the reduction in sensitivity. Below, a specific description is given of an appropriate positioning of the aperture according to the image height of the pixel 107 in the pixel array 101.

[0028] FIG. 3(a) is a schematic diagram of a pixel array 101. A pixel located near the center of the pixel array 101 is referred to as a first pixel, a pixel located away from the first pixel in a first direction is referred to as a second pixel, and a pixel located away from the first pixel in a second direction is referred to as a third pixel. FIG. 3(b) is a plan view of the front side of the first pixel, FIG. 3(c) is a plan view of the back side of the first pixel, and FIG. 3(d) is a cross-sectional view of the first pixel taken along the line B-B'. FIG. 3(e) is a plan view of the front side of the second pixel, FIG. 3(f) is a plan view of the back side of the second pixel, and FIG. 3(g) is a cross-sectional view of the second pixel taken along the line C-C'. FIG. 3(h) is a plan view of the front side of the third pixel, FIG. 3(i) is a plan view of the back side of the third pixel, and FIG. 3(j) is a cross-sectional view of the third pixel taken along the line D-D'.

[0029] In the first pixel, when the length of the first isolation portion from inter-pixel isolation portion 225 is Lc1, the length of the second isolation portion is Lc2, the length of the third isolation portion is Lc3, and the length of the fourth isolation portion is Lc4, Lc1 and Lc3 are equal, and Lc2 and Lc4 are also equal. In Figure 3(a), Lc1 = Lc2 = Lc3 = Lc4, and the areas of the four photoelectric conversion elements, first photoelectric conversion element 201, second photoelectric conversion element 202, third photoelectric conversion element 203, and fourth photoelectric conversion element 204, are equal.

[0030] In the second pixel, the length of the first isolation portion from the inter-pixel isolation portion 225 is Lb1, the length of the second isolation portion is Lb2, the length of the third isolation portion is Lb3, and the length of the fourth isolation portion is Lb4. Lb2 and Lb4 are equal, and Lb3 is shorter than Lb1. That is, the first opening expands in the first direction. It can also be said that the first opening shifts toward the periphery of the pixel array.

[0031] In the third pixel, the length of the first isolation portion from the inter-pixel isolation portion 225 is Lr1, the length of the second isolation portion is Lr2, the length of the third isolation portion is Lr3, and the length of the fourth isolation portion is Lr4. Lc1 and Lc3 are equal, and Lc4 is shorter than Lc2. In other words, the second opening expands in the second direction. It can also be said that the second opening is shifted toward the periphery of the pixel array.

[0032] In this configuration, for example, when comparing the first pixel and the second pixel, the length in the second direction of the second opening of the second pixel is equal to the length in the second direction of the second opening of the first pixel, while the area of ​​the first opening is increased by the amount that Lb3 is shorter than Lc3.

[0033] The second pixel is pixel 107, which is positioned downwardly from the center of pixel array 101. In a pixel positioned in this manner, the light-collecting position of microlens 230 is shifted downwardly from the center of the pixel, which may result in reduced sensitivity. In this embodiment, the first opening extends downward, thereby expanding the area sensitive to incident light where no separation section is provided. This makes it possible to perform optimal photoelectric conversion of light passing through microlens 230, eliminating or minimizing the reduction in sensitivity.

[0034] Similarly, the third pixel is pixel 107, which is positioned to the right of the center of pixel array 101. In a pixel positioned in this manner, the light-collecting position of microlens 230 may be shifted to the right from the center of the pixel, potentially resulting in reduced sensitivity. In this embodiment, the second opening extends to the right, thereby expanding the region sensitive to incident light where no separation section is provided to the right. This allows for optimal photoelectric conversion of light passing through microlens 230, eliminating or minimizing the reduction in sensitivity.

[0035] Because the light collection position in each pixel changes in a gradational manner according to the arrangement of the pixels 107 in the pixel array 101, it is desirable to also change the arrangement of the separation units in each pixel in a gradational manner. However, the arrangement of the separation units is not limited to a strict gradational change. For example, the pixel array 101 may be divided into three sections in each of the first and second directions, and divided into nine blocks, with the direction and amount of shift of the apertures set for each block. Alternatively, the pixel array 101 may be divided into two blocks, a central block and a peripheral block surrounding the central block, and only the apertures of the pixels 107 in the peripheral block may be shifted.

[0036] In this way, by varying the position of the separation section within the pixel depending on the image height, it is possible to prevent light from being incident on the separation section in areas of high image height, thereby preventing a decrease in sensitivity.

[0037] (Second embodiment) In the first embodiment, the arrangement of the openings was changed by making some of the separation sections shorter than the other separation sections. In the photoelectric conversion device according to the second embodiment, the separation section facing the shortened separation section is made longer than the other separation sections, thereby realizing a more suitable arrangement of the separation sections and openings. Descriptions common to the first embodiment will be omitted.

[0038] Fig. 4(a) is a schematic diagram of the pixel array 101. Fig. 4(b) is a plan view of the front side of a first pixel, and Fig. 4(c) is a plan view of the back side of the first pixel. Fig. 4(d) is a plan view of the front side of a second pixel, and Fig. 4(e) is a plan view of the back side of the second pixel. Fig. 4(f) is a plan view of the front side of a third pixel, and Fig. 4(g) is a plan view of the back side of the third pixel.

[0039] As shown in FIG. 4(c), the arrangement of the separation portion and the opening portion of the first pixel is the same as in the first embodiment.

[0040] As shown in FIG. 4(e), in the second pixel, Lb2 and Lb4 are equal, and Lb3 is shorter than Lb1. Here, Lb1 is longer than Lb2 and Lb4, and Lb3 is shorter than Lb2 and Lb4. Furthermore, Lb1 is longer than Lc1, and Lb3 is shorter than Lc3. In FIGS. 4(c) and 4(e), Lc1 and Lc3 are equal, and the difference between Lb1 and Lc1 is greater than the difference between Lb3 and Lc3. That is, the length of the first opening in the second pixel in the first direction is longer than the length of the first opening in the first pixel in the first direction. This is to prevent interference with the floating diffusion region formed in the center of the pixel, where charges generated in the photoelectric conversion device are transferred by the transfer transistor.

[0041] As shown in FIG. 4(g), in the third pixel, Lr1 and Lr3 are equal, and Lr4 is shorter than Lr2. Here, Lr2 is longer than Lr1 and Lr3, and Lr4 is shorter than Lr1 and Lr3. Also, in FIGS. 4(c) and 4(g), Lr2 is longer than Lc2, and Lr4 is shorter than Lc4. Lc1 and Lc3 are equal, and the difference between Lr4 and Lc4 is greater than the difference between Lr2 and Lc2. That is, the length in the second direction of the second opening of the third pixel is greater than the length in the second direction of the second opening of the first pixel.

[0042] In this way, by making the isolation section facing the isolation section that is becoming shorter longer than the other isolation sections, the total area of ​​the isolation sections is reduced, which suppresses the decrease in saturation capacitance caused by the decrease in PN junction capacitance, and reduces the impact on pixel performance.

[0043] (Third embodiment) The arrangement of the separator in the fourth pixel provided at the diagonal corner of the pixel array 101 will be described with reference to Fig. 5. Fig. 5(a) is a schematic diagram of the pixel array 101, Fig. 5(b) is a plan view of the front surface side of the fourth pixel, and Fig. 5(c) is a plan view of the back surface side of the fourth pixel.

[0044] As shown in Figure 5(b), in the fourth pixel, Lrb3 is shorter than Lrb1, and Lrb4 is shorter than Lrb2. That is, the length in the first direction of the first opening of the fourth pixel is greater than the first length of the first opening of the first pixel, and the length in the second direction of the second opening of the fourth pixel is greater than the length in the second direction of the first pixel of the second pixel. In Figure 5(b), Lrb1 and Lrb2 are equal, and Lrb2 and Lrb4 are also equal, but the separation portion may be arranged so that, for example, Lrb4 is shorter than Lrb3.

[0045] 5 shows pixel 107 located at the lower right of pixel array 101. In a pixel located in this position, the light-collecting position of microlens 230 is shifted downward and to the right from the center of the pixel, which may result in reduced sensitivity. In this embodiment, the first opening extends downward and the second opening extends rightward, so that the sensitive region where no separation section is provided extends downward and to the right. This allows light passing through microlens 230 to be suitably photoelectrically converted, thereby suppressing a reduction in sensitivity.

[0046] The embodiment of the present invention is not limited to changing the arrangement of the openings by making different the lengths of two separation parts facing each other in the first direction or the second direction. By changing the lengths of the separation parts arranged extending in the first direction and the separation parts arranged extending in the second direction and optimizing the arrangement of the openings, it is possible to prevent a decrease in sensitivity even for pixels 107 arranged diagonally in pixel array 101.

[0047] (Fourth embodiment) In the photoelectric conversion devices described in the first to third embodiments, the size of the opening was varied depending on the position of the pixel in the pixel array 101, but the position where the separation portion within the pixel contacts the inter-pixel separation portion was constant for each pixel. In contrast, in the fourth embodiment described with reference to Fig. 6, the position where each separation portion contacts the inter-pixel separation portion is also changed depending on the position of the pixel and the image height, thereby achieving a pixel configuration that is more suitable for suppressing a decrease in sensitivity.

[0048] FIG. 6(a) is a schematic diagram of the pixel array 101, FIG. 6(b) is a plan view of the front side of the second pixel, and FIG. 6(c) is a plan view of the back side of the second pixel. In the pixel 107 shown in FIG. 6, Lr1 is equal to Lr3, and Lr2 is greater than Lr4. Compared to the first pixel, the center of the second opening is shifted toward the fourth isolation portion (to the right in the figure), and accordingly, the position where the first isolation portion and the third isolation portion contact the inter-pixel isolation portion 225 (see FIG. 2) surrounding the four photoelectric conversion elements is shifted toward the fourth isolation portion. As a result, Wr1, which is the width between the first and third photoelectric conversion elements, is greater than Wr2, which is the width between the second and fourth photoelectric conversion elements. In other words, in this arrangement, the areas of the first and third photoelectric conversion elements are greater than the areas of the second and fourth photoelectric conversion elements.

[0049] (Fifth embodiment) A photoelectric conversion device according to a fifth embodiment will be described with reference to FIGS. 7 and 8. In the photoelectric conversion device shown in FIG. 7, in addition to the changes in the separation unit described in the fourth embodiment, the positions of the microlens 230, the color filter 240, and the color filter grid are changed according to the image height. The photoelectric conversion device shown in FIG. 8 further includes an inner lens 250, the position of which also changes according to the image height. FIG. 7(a) is a schematic diagram of the pixel array 101, and FIG. 7(b) is a plan view of the back surface of the second pixel. FIG. 7(c) is a cross-sectional view of the second pixel taken along the AA' cross section of FIG. 7(b). Similarly, FIG. 8(a) is a schematic diagram of the pixel array 101, and FIG. 8(b) is a plan view of the back surface of the second pixel. FIG. 8(c) is a cross-sectional view of the second pixel taken along the AA' cross section of FIG. 8(b).

[0050] In other words, the distance in the first direction between the center of the microlens 230 of the second pixel and the center of the second pixel is greater than the distance in the first direction between the center of the microlens 230 of a first pixel located in the central portion of the pixel array 101 and the center of this first pixel. Similarly, the distance in the first direction between the center of the inner lens 250 of the second pixel and the center of the second pixel is greater than the distance in the first direction between the center of the inner lens 250 of a first pixel located in the central portion of the pixel array 101 and the center of this first pixel. Furthermore, the distance in the first direction between the center of the color filter 240 of the second pixel and the center of the second pixel is greater than the distance in the first direction between the center of the color filter of the first pixel and the center of the first pixel.

[0051] This makes it possible to prevent a decrease in sensitivity in pixels at the periphery of the pixel array 101. Furthermore, by shifting the color filters, it is possible to perform photoelectric conversion of obliquely incident light at the appropriate pixel even at the edge of the pixel array 101, thereby ensuring color accuracy.

[0052] 8, the microlens 230, the color filter 240, and the inner lens 250 are configured so that they are all shifted from the pixel center by the same amount, but this is not limited to this. For example, the microlens 230 may be shifted the most from the pixel center, and the color filter 240 may be shifted from the pixel center by an amount that is the average of the shift amounts of the inner lens 250 and the microlens 230.

[0053] (Sixth embodiment) The sixth embodiment can be applied to any of the first to fifth embodiments. FIG. 9(a) is a schematic diagram illustrating a device 9191 including a semiconductor device 930 of this embodiment. The photoelectric conversion device of each of the above-described embodiments can be used for the semiconductor device 930. The device 9191 including the semiconductor device 930 will be described in detail. In addition to the semiconductor device 910, the semiconductor device 930 can include a package 920 that houses the semiconductor device 910. The package 920 can include a base to which the semiconductor device 910 is fixed and a lid such as glass that faces the semiconductor device 910. The package 920 can further include bonding members such as bonding wires and bumps that connect terminals provided on the base to terminals provided on the semiconductor device 910.

[0054] The equipment 9191 can include at least one of an optical device 940, a control device 950, a processing device 960, a display device 970, a storage device 980, and a mechanical device 990. The optical device 940 corresponds to the semiconductor device 930. The optical device 940 is, for example, a lens, a shutter, or a mirror, and includes an optical system that guides light to the semiconductor device 930. The control device 950 controls the semiconductor device 930. The control device 950 is, for example, a semiconductor device such as an ASIC.

[0055] The processing device 960 processes the signal output from the semiconductor device 930. The processing device 960 is a semiconductor device such as a CPU or ASIC for configuring an AFE (analog front end) or a DFE (digital front end). The display device 970 is an EL display device or a liquid crystal display device that displays information (images) obtained by the semiconductor device 930. The storage device 980 is a magnetic device or a semiconductor device that stores information (images) obtained by the semiconductor device 930. The storage device 980 is a volatile memory such as an SRAM or a DRAM, or a non-volatile memory such as a flash memory or a hard disk drive.

[0056] The mechanical device 990 has a moving part or a propulsion part such as a motor or an engine. In the device 9191, the signal output from the semiconductor device 930 is displayed on the display device 970, or transmitted to the outside by a communication device (not shown) provided in the device 9191. For this purpose, the device 9191 preferably further includes a memory device 980 and a processing device 960 in addition to the memory circuit and arithmetic circuit provided in the semiconductor device 930. The mechanical device 990 may be controlled based on the signal output from the semiconductor device 930.

[0057] The device 9191 is also suitable for electronic devices such as information terminals with a photographing function (for example, smartphones and wearable devices) and cameras (for example, interchangeable lens cameras, compact cameras, video cameras, and surveillance cameras). The mechanical device 990 in the camera can drive components of the optical device 940 for zooming, focusing, and shutter operation. Alternatively, the mechanical device 990 in the camera can move the semiconductor device 930 for vibration isolation operations.

[0058] Furthermore, the device 9191 may be transportation equipment such as a vehicle, a ship, or an aircraft. The mechanical device 990 in transportation equipment can be used as a moving device. The device 9191 as transportation equipment is suitable for transporting the semiconductor device 930 or for assisting and / or automating driving (piloting) using a photographing function. The processing device 960 for assisting and / or automating driving (piloting) can perform processing for operating the mechanical device 990 as a moving device based on information obtained by the semiconductor device 930. Alternatively, the device 9191 may be a medical device such as an endoscope, a measuring device such as a distance measuring sensor, an analytical device such as an electron microscope, an office machine such as a copier, or an industrial device such as a robot.

[0059] According to the above-described embodiment, it is possible to obtain good pixel characteristics. Therefore, the value of the semiconductor device can be increased. In this case, increasing the value corresponds to at least one of adding functions, improving performance, improving characteristics, improving reliability, improving manufacturing yield, reducing environmental impact, reducing costs, reducing size, and reducing weight.

[0060] Therefore, if the semiconductor device 930 according to this embodiment is used in the equipment 9191, the value of the equipment can also be improved. For example, by installing the semiconductor device 930 in a transport equipment, excellent performance can be obtained when photographing the exterior of the transport equipment or measuring the external environment. Therefore, when manufacturing and selling transport equipment, deciding to install the semiconductor device according to this embodiment in the transport equipment is advantageous in terms of improving the performance of the transport equipment itself. In particular, the semiconductor device 930 is suitable for transport equipment that performs driving assistance and / or automatic driving of the transport equipment using information obtained by the semiconductor device.

[0061] The photoelectric conversion system and the moving object of this embodiment will be described with reference to FIGS. 9(b) and 9(c).

[0062] FIG. 9(a) shows an example of a photoelectric conversion system related to an in-vehicle camera. The photoelectric conversion system 8 includes a photoelectric conversion device 80. The photoelectric conversion device 80 is the photoelectric conversion device (image capture device) described in any of the above embodiments. The photoelectric conversion system 8 includes an image processing unit 801 that performs image processing on multiple pieces of image data acquired by the photoelectric conversion device 80, and a parallax acquisition unit 802 that calculates parallax (phase difference between parallax images) from the multiple pieces of image data acquired by the photoelectric conversion system 8. The photoelectric conversion system 8 also includes a distance acquisition unit 803 that calculates the distance to an object based on the calculated parallax, and a collision determination unit 804 that determines whether or not there is a possibility of a collision based on the calculated distance. Here, the parallax acquisition unit 802 and the distance acquisition unit 803 are examples of distance information acquisition means that acquire information about the distance to the object. That is, the distance information is information about the parallax, the defocus amount, the distance to the object, etc. The collision determination unit 804 may determine the possibility of a collision using any of this distance information. The distance information acquisition means may be realized by dedicated hardware, a software module, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or a combination thereof.

[0063] The photoelectric conversion system 8 is connected to a vehicle information acquisition device 810 and can acquire vehicle information such as vehicle speed, yaw rate, and steering angle. The photoelectric conversion system 8 is also connected to a control ECU 820, which is a control device that outputs a control signal to generate a braking force for the vehicle based on the determination result of the collision determination unit 804. The photoelectric conversion system 8 is also connected to an alarm device 830 that issues an alarm to the driver based on the determination result of the collision determination unit 804. For example, if the determination result of the collision determination unit 804 indicates a high possibility of a collision, the control ECU 820 performs vehicle control to avoid the collision and mitigate damage by applying the brakes, releasing the accelerator, suppressing engine output, etc. The alarm device 830 warns the user by sounding an alarm, displaying alarm information on the screen of a car navigation system, etc., or vibrating the seat belt or steering wheel.

[0064] In this embodiment, the photoelectric conversion system 8 captures an image of the surroundings of the vehicle, for example, the front or rear.

[0065] 9(c) shows the photoelectric conversion system when capturing an image of the area ahead of the vehicle (image capturing range 850). A vehicle information acquisition device 810 sends instructions to the photoelectric conversion system 8 or the photoelectric conversion device 80. This configuration can further improve the accuracy of distance measurement.

[0066] Although the above describes an example of control to prevent collision with other vehicles, the present invention can also be applied to control of automatic driving by following other vehicles, and control of automatic driving to prevent deviation from a lane. Furthermore, the photoelectric conversion system is not limited to vehicles such as automobiles, but can be applied to moving bodies (moving devices) such as ships, aircraft, and industrial robots. In addition, the present invention can be applied not only to moving bodies but also to a wide range of devices that use object recognition, such as intelligent transport systems (ITS).

[0067] The above-described embodiments can be modified as appropriate without departing from the spirit of the present invention. The disclosure of this specification includes not only what is described herein but also all matters that can be understood from the specification and the accompanying drawings. The disclosure of this specification also includes the complement of the concepts described herein. In other words, if the specification contains a statement that "A is greater than B," even if the statement that "A is not greater than B" is omitted, the specification can still be said to disclose that "A is not greater than B." This is because the statement that "A is greater than B" presupposes that the case in which "A is not greater than B" is taken into consideration.

[0068] The present invention also includes the following configurations.

[0069] (Configuration 1) A photoelectric conversion device having a plurality of pixels arranged in an array, each of the plurality of pixels having a microlens. The device has a first photoelectric conversion element, a second photoelectric conversion element, a third photoelectric conversion element, and a fourth photoelectric conversion element arranged in two rows and two columns so as to receive light through the microlens. The device has a first isolation portion provided between the first photoelectric conversion element and the second photoelectric conversion element, and a second isolation portion provided between the first photoelectric conversion element and the third photoelectric conversion element. The device has a third isolation portion provided between the third photoelectric conversion element and the fourth photoelectric conversion element, and a fourth isolation portion provided between the second photoelectric conversion element and the fourth photoelectric conversion element. The first isolation portion, the third isolation portion, and a first opening provided between the first isolation portion and the third isolation portion are aligned in a first direction. the second isolation portion, the fourth isolation portion, and a second opening portion provided between the second isolation portion and the fourth isolation portion are aligned in a second direction; the plurality of pixels include a first pixel and a second pixel spaced apart in the first direction, the first pixel being closer to a center of the array of the plurality of pixels than the second pixel; and the arrangement of the first opening portion in the first pixel differs from the arrangement of the first opening portion in the second pixel.

[0070] (Configuration 2) The photoelectric conversion device described in configuration 1, characterized in that each of the plurality of pixels is surrounded on all four sides by an inter-pixel isolation portion, and the first isolation portion, the second isolation portion, the third isolation portion, and the fourth isolation portion are each arranged perpendicular to the inter-pixel isolation portion.

[0071] (Configuration 3) The photoelectric conversion device described in configuration 1 or 2, characterized in that the length in the first direction of the first opening of the second pixel is longer than the length in the first direction of the first opening of the first pixel.

[0072] (Configuration 4) The photoelectric conversion device according to any one of configurations 1 to 3, wherein the length in the first direction of the third separation portion of the second pixel is shorter than the length in the first direction of the third separation portion of the first pixel.

[0073] (Configuration 5) The photoelectric conversion device according to any one of configurations 1 to 4, wherein the length in the first direction of the first separation portion of the second pixel is longer than the length in the first direction of the first separation portion of the first pixel.

[0074] (Configuration 6) 6. The photoelectric conversion device according to any one of structures 1 to 5, wherein the area of ​​the third photoelectric conversion element of the second pixel is smaller than the area of ​​the third photoelectric conversion element of the first pixel.

[0075] (Configuration 7) The area of ​​the first photoelectric conversion element of the second pixel is 6. The photoelectric conversion device according to any one of Structures 1 to 5, wherein the area of ​​the first photoelectric conversion element of the first pixel is larger than the area of ​​the first photoelectric conversion element of the first pixel.

[0076] (Configuration 8) The photoelectric conversion device of any one of structures 1 to 7, wherein the length of the second opening of the second pixel in the second direction is shorter than the length of the second opening of the first pixel in the second direction.

[0077] (Configuration 9) The photoelectric conversion device of any one of structures 1 to 7, wherein the length of the second opening of the second pixel in the second direction is equal to the length of the second opening of the first pixel in the second direction.

[0078] (Configuration 10) The photoelectric conversion device of any one of structures 1 to 7, wherein the length of the second opening of the second pixel in the second direction is longer than the length of the second opening of the first pixel in the second direction.

[0079] (Configuration 11) The photoelectric conversion device according to any one of configurations 1 to 10, wherein the distance in the first direction between the center of the microlens of the second pixel and the center of the second pixel is greater than the distance in the first direction between the center of the microlens of the first pixel and the center of the first pixel.

[0080] (Configuration 12) 12. The photoelectric conversion device according to any one of configurations 1 to 11, wherein each of the plurality of pixels has a color filter provided on a light incident surface side, and a distance in the first direction between a center of the color filter of the second pixel and a center of the second pixel is greater than a distance in the first direction between a center of the color filter of the first pixel and a center of the first pixel.

[0081] (Configuration 13) 13. A photoelectric conversion system comprising: a photoelectric conversion device according to any one of configurations 1 to 12; and a signal processing unit that generates an image using a signal output from the photoelectric conversion device.

[0082] (Configuration 14) A photoelectric conversion system comprising: a photoelectric conversion device according to any one of configurations 1 to 12; and means for acquiring distance information to an object based on a signal output from the photoelectric conversion device.

[0083] (Configuration 15) A moving body including the photoelectric conversion device according to any one of configurations 1 to 12, characterized in that the moving body has a control unit that controls the movement of the moving body using a signal output by the photoelectric conversion device.

[0084] (Configuration 16) An apparatus including the photoelectric conversion device according to any one of configurations 1 to 12, further comprising at least one of the following: an optical device that guides light to the photoelectric conversion device; a control device that controls the photoelectric conversion device; a processing device that processes a signal output from the photoelectric conversion device; a display device that displays information obtained by the photoelectric conversion device; a storage device that stores information obtained by the photoelectric conversion device; or a mechanical device that operates based on information obtained by the photoelectric conversion device.

Claims

1. A photoelectric conversion device in which a plurality of pixels are arranged in an array, Each of the plurality of pixels includes a microlens; first photoelectric conversion elements, second photoelectric conversion elements, third photoelectric conversion elements, and fourth photoelectric conversion elements arranged in two rows and two columns so as to receive light via the microlenses; a first isolation portion provided between the first photoelectric conversion element and the second photoelectric conversion element; a second isolation portion provided between the first photoelectric conversion element and the third photoelectric conversion element; a third isolation portion provided between the third photoelectric conversion element and the fourth photoelectric conversion element; a fourth isolation portion provided between the second photoelectric conversion element and the fourth photoelectric conversion element, the first separation portion, the third separation portion, and a first opening portion provided between the first separation portion and the third separation portion are aligned in a first direction; the second separation portion, the fourth separation portion, and a second opening portion provided between the second separation portion and the fourth separation portion are aligned in a second direction; the plurality of pixels includes a first pixel and a second pixel spaced apart in a first direction, the first pixel being closer to a center of the array of pixels than the second pixel; A photoelectric conversion device, wherein an arrangement of the first openings in the first pixel is different from an arrangement of the first openings in the second pixel.

2. each of the plurality of pixels is surrounded on four sides by an inter-pixel separation portion; 2. The photoelectric conversion device according to claim 1, wherein the first isolation portion, the second isolation portion, the third isolation portion, and the fourth isolation portion are each provided perpendicular to the inter-pixel isolation portion.

3. The length of the first opening of the second pixel in the first direction is 2. The photoelectric conversion device according to claim 1, wherein the length of the first opening of the first pixel is longer than the length of the first opening in the first direction.

4. The length of the third isolation portion of the second pixel in the first direction is 4. The photoelectric conversion device according to claim 3, wherein the length in the first direction is shorter than the length of the third isolation portion of the first pixel.

5. The length of the first separation portion of the second pixel in the first direction is 5. The photoelectric conversion device according to claim 4, wherein the length in the first direction is longer than the length of the first isolation portion of the first pixel.

6. The area of ​​the third photoelectric conversion element of the second pixel is 6. The photoelectric conversion device according to claim 5, wherein the area of ​​the third photoelectric conversion element of the first pixel is smaller than the area of ​​the third photoelectric conversion element of the first pixel.

7. The area of ​​the first photoelectric conversion element of the second pixel is 7. The photoelectric conversion device according to claim 6, wherein the area of ​​the first photoelectric conversion element of the first pixel is larger than the area of ​​the first photoelectric conversion element of the first pixel.

8. The length of the second opening of the second pixel in the second direction is 4. The photoelectric conversion device according to claim 3, wherein the length of the second opening of the first pixel is shorter than the length of the second opening in the second direction.

9. The length of the second opening of the second pixel in the second direction is 4. The photoelectric conversion device according to claim 3, wherein the length is equal to the length of the second opening of the first pixel in the second direction.

10. The length of the second opening of the second pixel in the second direction is 4. The photoelectric conversion device according to claim 3, wherein the length of the second opening of the first pixel is longer than the length of the second opening in the second direction.

11. The length of the third isolation portion of the second pixel is 2. The photoelectric conversion device according to claim 1, wherein the length of the third isolation portion is shorter than the length of the third isolation portion of the first pixel.

12. The distance in the first direction between the center of the microlens of the second pixel and the center of the second pixel is 2. The photoelectric conversion device according to claim 1, wherein the distance is greater than the distance in the first direction between the center of the microlens of the first pixel and the center of the first pixel.

13. Each of the plurality of pixels has a color filter provided on a light incident surface side, The distance in the first direction between the center of the color filter of the second pixel and the center of the second pixel is 2. The photoelectric conversion device according to claim 1, wherein the distance is greater than the distance in the first direction between the center of the color filter of the first pixel and the center of the first pixel.

14. The photoelectric conversion device according to any one of claims 1 to 13, a signal processing unit that generates an image using a signal output from the photoelectric conversion device; A photoelectric conversion system comprising:

15. The photoelectric conversion device according to any one of claims 1 to 13, and means for acquiring information about the distance to an object based on the signal output from the photoelectric conversion device.

16. A moving object comprising the photoelectric conversion device according to any one of claims 1 to 13, A moving body comprising a control unit that controls the movement of the moving body using a signal output from the photoelectric conversion device.

17. An apparatus comprising the photoelectric conversion device according to any one of claims 1 to 13, an optical device that guides light to the photoelectric conversion device; a control device that controls the photoelectric conversion device; a processing device that processes a signal output from the photoelectric conversion device; a display device that displays information obtained by the photoelectric conversion device; a storage device that stores information obtained by the photoelectric conversion device; and and a mechanical device that operates based on information obtained by the photoelectric conversion device.

Images