image sensor

Abstract

An image sensor includes a pixel array and a logic circuit. The pixel array includes a pixel isolation layer between adjacent pixels in a plurality of pixels. Each of the plurality of pixels includes a pixel circuit under at least one photodiode. The logic circuit obtains a pixel signal from the plurality of pixels. The pixel array includes at least one autofocus pixel including a first photodiode, a second photodiode, a pixel-internal isolation layer between the first photodiode and the second photodiode, and a microlens over the first photodiode and the second photodiode. The pixel-internal isolation layer includes a first pixel-internal isolation layer and a second pixel-internal isolation layer separated from each other in a first direction perpendicular to an upper surface of a substrate, the first pixel-internal isolation layer and the second pixel-internal isolation layer including different materials.

Description

Technical Field

[0001] The inventive concept relates to an image sensor. Background Technology

[0002] An image sensor is a semiconductor-based sensor that receives light and generates electrical signals. It may include a pixel array with multiple pixels, logic circuitry that drives the pixel array and generates an image, etc. The logic circuitry can obtain pixel signals from the pixels to generate image data. Image sensors can provide autofocus functionality for focusing on an object. Summary of the Invention

[0003] One aspect of the inventive concept is to provide an image sensor that can reduce and / or minimize alignment errors that may occur when forming an isolation layer disposed between photodiodes, and limit and / or prevent saturation of the photodiodes.

[0004] According to one example embodiment, an image sensor may include: a pixel array including a substrate, a plurality of pixels arranged in a direction parallel to an upper surface of the substrate, and pixel isolation layers between adjacent pixels in the plurality of pixels, each of the plurality of pixels including at least one photodiode and pixel circuitry below the at least one photodiode; and logic circuitry configured to acquire pixel signals from the plurality of pixels. The pixel array may include at least one autofocus pixel. The at least one autofocus pixel may include a first photodiode, a second photodiode, an internal pixel isolation layer between the first and second photodiodes, and a microlens on the first and second photodiodes. The internal pixel isolation layer may include a first internal pixel isolation layer and a second internal pixel isolation layer. The first internal pixel isolation layer and the second internal pixel isolation layer may be separated from each other in a first direction. The first direction may be perpendicular to the upper surface of the substrate. The material of the first internal pixel isolation layer may be different from the material of the second internal pixel isolation layer.

[0005] According to one example embodiment, an image sensor may include: a substrate having a first surface and a second surface opposite to the first surface; a pixel array including a plurality of pixels and pixel isolation layers between adjacent pixels, the pixel isolation layers extending from the first surface of the substrate to the second surface of the substrate in a first direction perpendicular to the first surface, each of the plurality of pixels including at least one photodiode inside the substrate and pixel circuitry having a plurality of elements on the first surface; and logic circuitry configured to acquire pixel signals from the plurality of pixels. The pixel array may include at least one autofocus pixel, wherein the at least one autofocus pixel includes a first photodiode, a second photodiode, an internal pixel isolation layer extending from the first surface in the first direction between the first and second photodiodes, and a microlens on the second surface. The internal pixel isolation layers may include a first internal pixel isolation layer extending from the first surface and a second internal pixel isolation layer extending from the second surface. The first and second internal pixel isolation layers may have different shapes in a plane parallel to the first surface.

[0006] According to one example embodiment, an image sensor may include: a substrate having a first surface and a second surface opposite to the first surface; a pixel array including a plurality of pixels and pixel isolation layers between adjacent pixels in the plurality of pixels, the pixel isolation layers extending from the first surface in a first direction perpendicular to the first surface, each of the plurality of pixels including at least one photodiode and a pixel circuit, the pixel circuit having a plurality of elements on the first surface; and logic circuitry configured to acquire pixel signals from the plurality of pixels. The pixel array may include at least one autofocus pixel. The autofocus pixel may include a first photodiode and a second photodiode spaced apart from each other in a second direction parallel to the first surface, an internal pixel isolation layer extending from the first surface in the first direction between the first photodiode and the second photodiode, and a microlens on the second surface. The internal pixel isolation layer may have a first vertical surface and a second vertical surface extending in the first direction and opposite to each other in a third direction intersecting the second direction. At least one of the first vertical surface and the second vertical surface may be separated from the pixel isolation layer. Attached Figure Description

[0007] The above and other aspects, features and effects of the inventive concept will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0008] Figure 1 This is a block diagram schematically illustrating an image sensor according to one embodiment of the inventive concept.

[0009] Figures 2 to 4This is a schematic view illustrating the pixel array of an image sensor according to an embodiment of the inventive concept.

[0010] Figure 5 This is a schematic view illustrating the pixel circuitry of an image sensor according to one embodiment of the inventive concept.

[0011] Figures 6 to 11 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0012] Figures 12 to 15 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0013] Figure 16 and Figure 17 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0014] Figure 18 and Figure 19 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0015] Figures 20 to 22 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0016] Figures 23 to 26 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0017] Figure 27 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0018] Figures 28 to 33 This is a view illustrating a method for manufacturing an image sensor according to one embodiment of the inventive concept.

[0019] Figures 34 to 41 This is a view illustrating a method for manufacturing an image sensor according to one embodiment of the inventive concept.

[0020] Figure 42 and Figure 43 This is a schematic view of an electronic device including an image sensor according to one embodiment of the inventive concept. Detailed Implementation

[0021] In the following description, exemplary embodiments of the inventive concept will be described with reference to the accompanying drawings.

[0022] Figure 1This is a block diagram schematically illustrating an image sensor according to one embodiment of the inventive concept.

[0023] Reference Figure 1 The image sensor 1 may include a pixel array 10, logic circuits 20, etc.

[0024] The pixel array 10 may include a plurality of pixels PX arranged in an array shape along a plurality of rows and columns. Each of the plurality of pixels PX may include at least one photoelectric conversion element that generates an electric charge in response to light, a pixel circuit that generates a pixel signal corresponding to the electric charge generated by the photoelectric conversion element, etc. The photoelectric conversion element may include a photodiode formed of a semiconductor material, an organic photodiode formed of an organic material, etc.

[0025] For example, a pixel circuit may include a floating diffuser, a transfer transistor, a reset transistor, a drive transistor, and a selection transistor. The configuration of the pixel PX can vary depending on the implementation. As an example, each pixel PX may include an organic photodiode containing organic materials or may be implemented as a digital pixel. When a pixel PX is implemented as a digital pixel, each pixel PX may include an analog-to-digital converter for outputting digital pixel signals.

[0026] The logic circuit 20 may include circuitry for controlling the pixel array 10. For example, the logic circuit 20 may include a row driver 21, a readout circuit 22, a column driver 23, control logic 24, etc. The row driver 21 can drive the pixel array 10 on a row-line basis. For example, the row driver 21 can generate transfer control signals for controlling the transfer transistors of the pixel circuitry, reset control signals for controlling the reset transistors, selection control signals for controlling the selection transistors, etc., to input them into the pixel array 10 on a row-line basis.

[0027] The readout circuit 22 may include a correlated double sampler (CDS), an analog-to-digital converter (ADC), etc. The correlated double sampler can be connected to the pixel PX via column lines. The correlated double sampler can read pixel signals from the pixel PX connected to the row line selected by the row line selection signal of the row driver 21 via the column lines. The ADC can convert the pixel signals detected by the correlated double sampler into digital pixel signals and can transmit the digital pixel signals to the column driver 23.

[0028] The column driver 23 may include an amplifier circuit, a latch circuit or a buffer circuit for temporarily storing digital pixel signals, and can process the digital pixel signals received from the readout circuit 22. The row driver 21, the readout circuit 22 and the column driver 23 can be controlled by control logic 24. The control logic 24 may include a timing controller for controlling the operating timing of the row driver 21, the readout circuit 22 and the column driver 23.

[0029] In a pixel PX, pixels PX positioned at the same horizontal position can share the same column line. For example, pixels PX positioned at the same vertical position can be simultaneously selected by the row driver 21, and pixel signals can be output via the column line. In one embodiment, the readout circuit 22 can simultaneously acquire pixel signals from the pixels PX selected by the row driver 21 via the column line. The pixel signal may include a reset voltage and a pixel voltage. The pixel voltage may be a voltage in which the charge generated in response to light in each pixel PX is reflected in the reset voltage.

[0030] In one embodiment, the pixel array 10 may include at least one autofocus pixel. The autofocus pixel may include two or more photodiodes. The logic circuit 20 may utilize the differences in pixel signals acquired from the photodiodes included in each autofocus pixel to implement the autofocus function of the image sensor 1 and / or the autofocus function of a camera device including the image sensor 1.

[0031] To accurately calculate the difference in pixel signals acquired from two or more photodiodes included in an autofocus pixel, the autofocus pixel may include an internal pixel isolation layer for separating the photodiodes. Because the photodiodes can be separated from each other by the internal pixel isolation layer, the light-receiving area of ​​each photodiode can be determined based on the position of the internal pixel isolation layer. When the position of the internal isolation layer within the pixel is not accurately aligned and the light-receiving area of ​​each photodiode differs, the autofocus function of the image sensor 1 may deteriorate.

[0032] In one embodiment of the inventive concept, in order to reduce and / or minimize the error in the light-receiving area of ​​each photodiode in the autofocus pixel, an internal pixel isolation layer can be formed from a first surface of a substrate, similar to the pixel isolation layer between pixels PX. For example, the first surface can be the surface on which the pixel circuitry included in each pixel PX is formed. For example, the internal pixel isolation layer can be formed in the same process as the pixel isolation layer. Therefore, the alignment error of the internal pixel isolation layer can be reduced and / or minimized, and the error in the light-receiving area of ​​each photodiode can be reduced, thereby improving the autofocus function of the image sensor 1. Furthermore, even when the area of ​​each pixel PX is reduced to improve the resolution of the image sensor 1, the autofocus function of the image sensor 1 can be effectively achieved.

[0033] Figures 2 to 4 This is a schematic view illustrating the pixel array of an image sensor according to an embodiment of the inventive concept.

[0034] First, refer to Figure 2According to one embodiment of the inventive concept, the pixel array 100 of an image sensor may include a plurality of pixels 110 and 120, such as R, G, and B pixels. For example, the pixel array 100 may include general pixels 110 and autofocus pixels 120. The general pixels 110 and the autofocus pixels 120 may each be provided in multiples, and the number of each may vary in various ways. For example, the number of general pixels 110 may be greater than the number of autofocus pixels 120. Furthermore, the position of the autofocus pixels 120 is not limited to... Figure 2 The position shown can be changed in various ways.

[0035] Each autofocus pixel 120 may include a first photodiode and a second photodiode. In the autofocus pixel 120, the first photodiode and the second photodiode may be arranged in one direction (horizontal direction), and the first photodiode and the second photodiode may share a microlens. According to an embodiment, in some autofocus pixels 120, the first photodiode and the second photodiode may be arranged in a direction different from the stated one direction.

[0036] Reference Figure 3 The pixel array 100A may include a plurality of pixels 110A, such as R, G, and B pixels. Each of the plurality of pixels 110A may include a first photodiode and a second photodiode. Figure 3 In the illustrated embodiment, each pixel 110A included in the pixel array 100A can be an autofocus pixel. Similar to the above reference... Figure 2 In at least a portion of pixels 110A, the first photodiode and the second photodiode can be arranged in different directions, for example, in the vertical direction. According to an embodiment, only a portion of pixels 110A can be used for the autofocus function.

[0037] Next, refer to Figure 4 Pixel array 100B may include multiple pixel groups 110B. Each of the multiple pixel groups 110B may include unit pixels PX, such as R, G, and B pixels. The unit pixels PX included in each pixel group 110B may include color filters with the same color. Figure 4 In the illustrated embodiment, each unit pixel PX may include a first photodiode and a second photodiode. According to the embodiment, only a portion of the unit pixels PX may include the first photodiode and the second photodiode, or the arrangement directions of the first photodiode and the second photodiode in at least a portion of the unit pixels PX may be different.

[0038] In reference Figures 2 to 4In the described embodiment, an internal isolation layer may be disposed between the first photodiode and the second photodiode. For example, the light-receiving area of ​​each of the first and second photodiodes may be determined by the internal isolation layer. When the internal isolation layer is not properly aligned between the first and second photodiodes, a difference may occur between the light-receiving areas of the first and second photodiodes, thereby degrading the autofocus function of the image sensor.

[0039] In one embodiment of the inventive concept, the internal pixel isolation layer can be formed together with the pixel isolation layer that separates the pixels from each other. For example, trenches for forming the pixel isolation layer and trenches for forming the internal pixel isolation layer can be formed simultaneously in a single process. Therefore, the internal pixel isolation layer can be accurately aligned and the difference in light-receiving area between the first photodiode and the second photodiode can be reduced and / or minimized, thereby limiting and / or preventing degradation of the autofocus function of the image sensor.

[0040] Figure 5 This is a schematic view illustrating the pixel circuitry of an image sensor according to one embodiment of the inventive concept.

[0041] As an example, Figure 5 This could be a circuit diagram showing a pixel circuit including a first photodiode and a second photodiode separated from each other by an internal pixel isolation layer and providing autofocus functionality. The pixel circuit providing autofocus functionality is not necessarily limited to, for example... Figure 5 As shown, components can be added or omitted as necessary.

[0042] Reference Figure 5 The pixel circuit can be connected to a first photodiode PD1 and a second photodiode PD2, and can output a reset voltage and a pixel voltage via the column line COL. For example, the pixel circuit may include a first transfer transistor TX1, a second transfer transistor TX2, a reset transistor RX, a drive transistor DX, a selection transistor SX, and a conversion gain transistor DCX. The pixel circuit can be connected to the logic circuit of the image sensor via the column line COL. The logic circuit can obtain the reset voltage and pixel voltage via the column line COL to generate a pixel signal.

[0043] When the first photodiode PD1 and the second photodiode PD2 are exposed to light to generate charge during the exposure period, the first transfer transistor TX1 and the second transfer transistor TX2 can be turned on sequentially. The logic circuit can provide an autofocus function using a first pixel signal obtained after turning on the first transfer transistor TX1 and a second pixel signal obtained after turning on the second transfer transistor TX2. A reset signal RG can be used to turn the reset transistor RX on and off. A conversion gain signal DCR can be used to turn the conversion gain transistor DCX on and off. A first transfer signal TG1 and a second transfer signal TG2 can be used to turn the first transfer transistor TX1 and the second transfer transistor TX2 on and off, respectively. A selection signal SEL can be used to turn the selection transistor SX on and off. A floating diffusion node FD can be located between the first transfer transistor TX1 and the drive transistor DX, and between the second transfer transistor TX2 and the conversion gain transistor DCX. The pixel circuit can be configured to receive the power supply voltage VDD through an electrical connection with the reset transistor RX and the drive transistor DX.

[0044] Figures 6 to 11 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0045] Figure 6 This may be a simplified view showing a portion of pixels PX1, PX2, PX3, and PX4 included in an image sensor 200 according to one embodiment of the inventive concept. Figure 7 It can be Figure 6 A cross-sectional view taken along the cutting line I-I'. Figure 8 It can be Figure 6 The cross-sectional view taken along cutting line II-II'. (Refer to...) Figures 6 to 8 The pixel isolation layer 210 can be disposed between adjacent pixels in pixels PX1 to PX4, and each of pixels PX1 to PX4 can include an internal pixel isolation layer 220. The internal pixel isolation layer 220 can be disposed between the first photodiode PD1 and the second photodiode PD2. The pixel isolation layer 210 and the internal pixel isolation layer 220 can extend along a first direction (Z-axis direction) within the substrate 201 including semiconductor material.

[0046] The pixel circuit can be disposed below the first photodiode PD1 and the second photodiode PD2. For example, the pixel circuit may include a plurality of elements 230, a wiring pattern 231 connected to the plurality of elements 230, an insulating layer 232 covering the plurality of elements 230 and the wiring pattern 231, etc., and can be disposed on the first surface of the substrate 201.

[0047] The pixel circuit may include floating diffusers FD1 and FD2. For example, each of pixels PX1 to PX4 may include a first floating diffuser FD1 and a second floating diffuser FD2. The first floating diffuser FD1 may be disposed below the first photodiode PD1, and the second floating diffuser FD2 may be disposed below the second photodiode PD2. The first floating diffuser FD1 and the second floating diffuser FD2 may be electrically connected to each other through at least one of the wiring patterns 231, and the positions, areas, etc. of the first floating diffuser FD1 and the second floating diffuser FD2 may be varied according to various embodiments.

[0048] The first floating diffuser FD1 and the second floating diffuser FD2 can be disposed on both sides of the internal isolation layer 220 of the pixel. The element 230 adjacent to the first floating diffuser FD1 and the second floating diffuser FD2 can be a first transfer transistor and a second transfer transistor, respectively. The gate of each of the first transfer transistor and the second transfer transistor can have a vertical structure in which at least a portion of the gate is embedded in the substrate 201.

[0049] Each of pixels PX1 to PX4 may include color filters 202 and 203, a light-transmitting layer 204, and a microlens 205 disposed on the second surface of substrate 201. As an example, each of pixels PX1 to PX4 may include a microlens 205 disposed on or above the first photodiode PD1 and the second photodiode PD2. Therefore, light that has passed through the microlens 205 can be guided into the first photodiode PD1 and the second photodiode PD2.

[0050] Reference Figure 6 The pixel isolation layer 210 may have a first width W1, and the pixel-internal isolation layer 220 may have a second width W2 that is narrower than the first width W1. For example, the pixel-internal isolation layer 220 may be configured to have a width narrower than that of the pixel isolation layer 210, so that the pixel isolation layer 210 and the pixel-internal isolation layer 220 can be formed simultaneously in a single process. According to an embodiment, the pixel isolation layer 210 and the pixel-internal isolation layer 220 may be formed to have the same width. Furthermore, referring to… Figure 7 and Figure 8 In the first direction, the pixel isolation layer 210 may have a first length d1, and the pixel internal isolation layer 220 may have a second length d2, wherein the first length d1 may be longer than the second length d2. For example, the pixel isolation layer 210 may completely penetrate the substrate 201 and may extend from the first surface of the substrate 201 to the second surface of the substrate 201.

[0051] In one embodiment, in the first direction, the pixel internal isolation layer 220 may have a length shorter than the length of the first photodiode PD1 and the second photodiode PD2. The charge on the first photodiode PD1 and the second photodiode PD2 can move when the pixel internal isolation layer 220 is inserted therebetween. Therefore, when light is concentrated on the first photodiode PD1 or the second photodiode PD2, excess charge can be moved to limit and / or prevent saturation of the photodiodes PD1 and PD2.

[0052] exist Figures 6 to 8 In the illustrated embodiment, the pixel isolation layer 210 and the pixel internal isolation layer 220 can be formed using the same process, and both can extend from the first surface of the substrate 201 on which the pixel circuitry is disposed. The pixel isolation layer 210 and the pixel internal isolation layer 220 can be formed using the same process to accurately align the position of the pixel internal isolation layer 220 within each of pixels PX1 to PX4 and reduce and / or minimize the difference in light-receiving area between the first photodiode PD1 and the second photodiode PD2, thereby improving the autofocus function of the image sensor 200.

[0053] Next, refer to Figure 9 In pixels PX1 to PX4, the internal isolation layer 220 may include a first internal isolation layer 221 and a second internal isolation layer 222. The first internal isolation layer 221 extends from a first surface of the substrate 201 on which pixel circuitry is disposed, and the second internal isolation layer 222 extends from a second surface of the substrate 201 on which color filters 202 and 203, a light-transmitting layer 204, a microlens 205, etc., are disposed. In a first direction, the length of the first internal isolation layer 221 may be longer than the length of the second internal isolation layer 222.

[0054] In one embodiment, the first pixel internal isolation layer 221 may be formed of a first material, and the second pixel internal isolation layer 222 may be formed of a second material different from the first material. For example, the second material may have a higher reflectivity than the first material. Furthermore, in one embodiment, the first pixel internal isolation layer 221 may be formed of a conductive material, and the second pixel internal isolation layer 222 may be formed of an insulating material. For example, the first pixel internal isolation layer 221 may be formed of polysilicon, and the second pixel internal isolation layer 222 may be formed of silicon oxide.

[0055] The second pixel internal isolation layer 222 can be formed of a material with relatively high reflectivity to reflect light passing through the microlens 205 and directly incident on the second pixel internal isolation layer 222 to the first photodiode PD1 or the second photodiode PD2. Therefore, the sensitivity of the image sensor 200A can be improved. Furthermore, the first pixel internal isolation layer 221 can be formed of a conductive material, and a predetermined bias voltage, such as a negative voltage, can be applied to reduce dark current generated in pixels PX1 to PX4. For example, the pixel circuitry can apply a negative voltage to the first pixel internal isolation layer 221 while the logic circuitry acquires pixel signals from pixels PX1 to PX4.

[0056] Impurity region 240 can be disposed between the first pixel internal isolation layer 221 and the second pixel internal isolation layer 222. For example, impurity region 240 can be a region doped with P-type impurities. The impurity region 240 between the first pixel internal isolation layer 221 and the second pixel internal isolation layer 222 can provide an efficient charge transfer path between the first photodiode PD1 and the second photodiode PD2. According to an embodiment, impurity region 240 can be doped with N-type impurities. According to an embodiment, such as... Figure 10 As shown, only the impurity region 240 can be set between the pixel internal isolation layer 220 and the color filters 202 and 203 without a second pixel internal isolation layer 222.

[0057] In one embodiment, the impurity region 240 can be formed using the same process as forming the first pixel internal isolation layer 221. For example, a trench extending from a first surface of the substrate 201 for forming the first pixel internal isolation layer 221 can be formed, and impurities can be injected into the trench to prepare the impurity region 240. The trench for forming the first pixel internal isolation layer 221 can be formed first, and then impurities can be injected to reduce alignment errors between the impurity region 240 and the pixel internal isolation layer 220 and to perform the impurity injection operation with relatively low energy. Depending on the impurity injection operation, at least a portion of the impurity region 240 can overlap with the second pixel internal isolation layer 222.

[0058] Next, refer to Figure 11 In pixels PX1 to PX4, the pixel-internal isolation layer 220 may include a first pixel-internal isolation layer 221 and a second pixel-internal isolation layer 222, and the impurity region 240 may be formed between the first pixel-internal isolation layer 221 and the second pixel-internal isolation layer 222. The first pixel-internal isolation layer 221, the second pixel-internal isolation layer 222, and the impurity region 240 can be referenced above. Figure 9 and Figure 10 Use the description to understand.

[0059] exist Figure 11In the illustrated embodiment, the pixel isolation layer 210 may include a first pixel isolation layer 211 and a second pixel isolation layer 212. In a first direction, the length of the first pixel isolation layer 211 may be longer than the length of the second pixel isolation layer 212. Furthermore, the second pixel isolation layer 212 may be formed of a material having a higher reflectivity than the first pixel isolation layer 211. In one embodiment, the first pixel isolation layer 211 may be formed of the same material as the first pixel internal isolation layer 221, and the second pixel isolation layer 212 may be formed of the same material as the second pixel internal isolation layer 222.

[0060] The second pixel isolation layer 212 can be formed of a material with relatively high reflectivity to reflect a portion of the light that passes through the microlens 205 and is directly incident on the second pixel isolation layer 212 to the first photodiode PD1 or the second photodiode PD2. To reduce the amount of light absorbed by the first pixel isolation layer 211, the second pixel isolation layer 212 can be formed to have a length in a first direction that is longer than the length of the inner isolation layer 222 of the second pixel. (Refer to...) Figure 11 In the first direction, the length of the first pixel isolation layer 211 can be shorter than the length of the first pixel inner isolation layer 221, and the length of the second pixel isolation layer 212 can be longer than the length of the second pixel inner isolation layer 222.

[0061] Figures 12 to 15 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0062] Figure 12 It may be a plan view showing a portion of pixels PX1 to PX4 included in an image sensor 300 according to one embodiment of the inventive concept. Figure 13 and Figure 15 It can be Figure 12 A cross-sectional view taken along cutting line III-III'. Figure 14 It can be Figure 12 The cross-sectional view taken along the cutting line IV-IV'. First, refer together... Figure 12 and Figure 13 An image sensor 300 according to one embodiment may include a plurality of pixels PX1 to PX4. A pixel isolation layer 310 may be disposed between adjacent pixels of the plurality of pixels PX1 to PX4, and each of pixels PX1 to PX4 may include a first photodiode PD1 and a second photodiode PD2, separated from each other by an internal pixel isolation layer 320. The pixel isolation layer 310 and the internal pixel isolation layer 320 may extend in a first direction (Z-axis direction).

[0063] In reference Figure 12 and Figure 15In the described embodiment, the pixel-internal isolation layer 320 may have a first vertical surface VS1 and a second vertical surface VS2. The first vertical surface VS1 and the second vertical surface VS2 may be arranged opposite to each other in a third direction (Y-axis direction) intersecting a second direction (X-axis direction) that intersects the arrangement of the first photodiode PD1 and the second photodiode PD1. (Refer to...) Figure 12 The second vertical surface VS2 can be in direct contact with the pixel isolation layer 310, while the first vertical surface VS1 can be separated from the pixel isolation layer 310.

[0064] In one embodiment, the floating diffusion section FD can be disposed between the first vertical surface VS1 and the pixel isolation layer 310. Therefore, in each of pixels PX1 to PX4, the first photodiode PD1 and the second photodiode PD2 can share the floating diffusion section FD. Furthermore, because excess charge generated in at least one of the first photodiode PD1 and / or the second photodiode PD2 can move through the space between the first vertical surface VS1 and the pixel isolation layer 310, the pixel-internal isolation layer 320 can completely penetrate the substrate 301, such as... Figure 13 and Figure 15 As shown. As an example, the pixel internal isolation layer 320 can extend from a first surface of the substrate 301 on which the pixel circuit is disposed to a second surface of the substrate 301 on which the color filters 302 and 303, the light-transmitting layer 304 and the microlens 305 are disposed.

[0065] Reference Figure 15 The pixel internal isolation layer 320 may include a first pixel internal isolation layer 321 and a second pixel internal isolation layer 322. The first pixel internal isolation layer 321 may be formed of a first material, and the second pixel internal isolation layer 322 may be formed of a second material different from the first material, and the second material may have a higher reflectivity than the first material. Therefore, light passing through the microlens 305 and directly incident on the pixel internal isolation layer 320 instead of the first photodiode PD1 and the second photodiode PD2 may not be absorbed by the pixel internal isolation layer 320 and may be reflected by the pixel internal isolation layer 320, and may be guided to the first photodiode PD1 or the second photodiode PD2, thereby improving the sensitivity of the image sensor 300A.

[0066] For example, the first material can be polycrystalline silicon, and the second material can be silicon oxide. Furthermore, although... Figure 15The interface between the first pixel internal isolation layer 321 and the second pixel internal isolation layer 322 is positioned below the upper surface of the first photodiode PD1 and the second photodiode PD2, but the interface between the first pixel internal isolation layer 321 and the second pixel internal isolation layer 322 can be positioned above the upper surface of the first photodiode PD1 and the second photodiode PD2.

[0067] For example, in pixels PX1 to PX4 respectively, the second pixel internal isolation layer 322 may contact the pixel isolation layer 310 in the third direction. For example, in the third direction, the second pixel internal isolation layer 322 may be connected to the pixel isolation layers 310 on both sides of each of pixels PX1 to PX4. In this case, in the third direction, the length of the first pixel internal isolation layer 321 may be shorter than the length of the second pixel internal isolation layer 322.

[0068] Figure 16 and Figure 17 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0069] exist Figure 16 and Figure 17 In the illustrated embodiments, image sensors 400 and 400A may include a plurality of pixels PX1 to PX4, each separated by a pixel isolation layer 410. Each of the plurality of pixels PX1 to PX4 may include an internal pixel isolation layer 420, a first photodiode PD1, and a second photodiode PD2. First, referring to... Figure 16 The pixel-internal isolation layer 420 may include a first vertical surface VS1 and a second vertical surface VS2, and one of the first vertical surface VS1 and the second vertical surface VS2 may be in direct contact with the pixel isolation layer 410, while the other may be separated from the pixel isolation layer 410. Furthermore, in Figure 16 In the embodiment shown, pixels that are adjacent to each other in the third direction (Y-axis direction), such as first pixel PX1 and third pixel PX3, can form a structure in which first pixel PX1 and third pixel PX3 are perpendicularly symmetrical to each other.

[0070] exist Figure 17 In the illustrated embodiment, the first vertical surface VS1 and the second vertical surface VS2 of the pixel internal isolation layer 420A can be separated from the pixel isolation layer 410. (Refer to...) Figure 17In the third direction (Y-axis direction), the first floating diffusion section FD1 can be disposed between the first vertical surface VS1 and the pixel isolation layer 410, and the second floating diffusion section FD2 can be disposed between the second vertical surface VS2 and the pixel isolation layer 410. The first floating diffusion section FD1 and the second floating diffusion section FD2 can be electrically connected to each other through wiring patterns, etc. According to other embodiments, only one of the first floating diffusion section FD1 and the second floating diffusion section FD2 can be disposed in each of pixels PX1 to PX4.

[0071] In addition, Figure 16 and Figure 17 In the illustrated embodiment, each of the pixel internal isolation layers 420 and 420A may include a first internal isolation layer and a second internal isolation layer. The first and second internal isolation layers may be in direct contact with each other or may be separated from each other. When the first and second internal isolation layers are separated from each other, an impurity region may be formed therebetween. Furthermore, the first and second internal isolation layers may have different shapes. In one embodiment, the first and second internal isolation layers may have different lengths in a third direction. Alternatively, an impurity region may be formed between the first internal isolation layer and the color filter, without a second internal isolation layer.

[0072] Figure 18 and Figure 19 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0073] Figure 18 This may be a simplified view showing a portion of pixels PX1 to PX4 included in an image sensor 500 according to one embodiment of the inventive concept. Figure 19 It can be Figure 18 A cross-sectional view taken along the cutting line V-V'. Pixels PX1 to PX4 can be separated from each other by pixel isolation layer 510, and in each of pixels PX1 to PX4, the first photodiode PD1 and the second photodiode PD2 can be separated from each other by pixel internal isolation layer 520. Pixel isolation layer 510 and pixel internal isolation layer 520 can extend inside substrate 501 in a first direction (Z-axis direction).

[0074] The pixel isolation layer 510 can extend from the first surface of the substrate 501 to the second surface of the substrate 501. For example, the first surface can be a surface on which a plurality of elements 530, wiring patterns 531, insulating layers 532, etc. are disposed, and the second surface can be a surface on which color filters 502 and 503, light-transmitting layers 504, microlenses 505, etc. are disposed.

[0075] The pixel internal isolation layer 520 may include a first pixel internal isolation layer 521 and a second pixel internal isolation layer 522. The first pixel internal isolation layer 521 and the second pixel internal isolation layer 522 may intersect each other. The first photodiode PD1 and the second photodiode PD2 may be separated from each other by the first pixel internal isolation layer 521, and in the second direction (X-axis direction) and the third direction (Y-axis direction), the second pixel internal isolation layer 522 may not overlap with the first photodiode PD1 and the second photodiode PD2.

[0076] Reference Figure 18 On the first surface, the second pixel internal isolation layer 522 can extend in the second direction, and the first pixel internal isolation layer 521 can extend upward in the third direction. (Refer to...) Figure 19 The first pixel internal isolation layer 521 and the second pixel internal isolation layer 522 may be separated from each other in a first direction, and the impurity region 540 may be formed therebetween. The first pixel internal isolation layer 521 is shown to have a length in the first direction that is shorter than the length of the first photodiode PD1 and the length of the second photodiode PD2, but is not limited thereto.

[0077] The first pixel internal isolation layer 521 and the second pixel internal isolation layer 522 can be formed of different materials. For example, the first pixel internal isolation layer 521 can be formed of a conductive material, and the second pixel internal isolation layer 522 can be formed of an insulating material. Furthermore, in one embodiment, the second pixel internal isolation layer 522 can be formed to have a higher reflectivity than the first pixel internal isolation layer 521. In this case, light passing through the microlens 505 can be reflected from the second pixel internal isolation layer 522, and the reflected light can then be guided to the first photodiode PD1 or the second photodiode PD2.

[0078] On the first surface of substrate 501, the width of the first pixel internal isolation layer 521 and the width of the second pixel internal isolation layer 522 may be equal to or narrower than the width of the pixel isolation layer 510. Each width here refers to the dimension of the respective element in a direction perpendicular to its respective extension direction. In one embodiment, the first pixel internal isolation layer 521 and the second pixel internal isolation layer 522 may have the same width.

[0079] Figures 20 to 22 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0080] First, refer to Figure 20The pixels PX1 to PX4 of the image sensor 600 can be separated from each other by a pixel isolation layer 610, and each of the pixels PX1 to PX4 can include a first internal pixel isolation layer 621 and a second internal pixel isolation layer 622. Similar to the above reference... Figure 18 and Figure 19 In the described implementation, the first pixel internal isolation layer 621 and the second pixel internal isolation layer 622 can be separated from each other in the first direction (Z-axis direction). Furthermore, in the second direction (X-axis direction) and the third direction (Y-axis direction), the second pixel internal isolation layer 622 may not overlap with the first photodiode PD1 and the second photodiode PD2.

[0081] exist Figure 20 In the illustrated embodiment, the second pixel internal isolation layer 622 may extend diagonally in each of pixels PX1 to PX4. According to the embodiment, in at least a portion of pixels PX1 to PX4, the second pixel internal isolation layer 622 may extend in different directions. For example, in the first pixel PX1, the second pixel internal isolation layer 622 may extend in a direction at 45 degrees relative to the second direction. In the second pixel PX2, the second pixel internal isolation layer 622 may extend in a direction at 135 degrees relative to the second direction.

[0082] like Figure 20 As shown, the second pixel internal isolation layer 622 can be disposed diagonally to utilize pixel signals obtained from each of the first photodiode PD1 and the second photodiode PD2 when implementing autofocus functions in different directions. As an example, in Figure 20 In the illustrated embodiment, the pixel signal obtained from each of the first photodiode PD1 and the second photodiode PD2 of the first pixel PX1 can also be used to achieve autofocus in the vertical direction. Figure 20 In the embodiment shown, since the second pixel internal isolation layer 622 can extend in the diagonal direction, the length of the second pixel internal isolation layer 622 can be longer than the length of the first pixel internal isolation layer 621 on a plane parallel to the upper surface of the substrate.

[0083] Next, refer to Figure 21 The pixels PX1 to PX4 of the image sensor 700 can be separated by a pixel isolation layer 710, and each of the pixels PX1 to PX4 can include an internal pixel isolation layer 720 extending in a diagonal direction. Therefore, as... Figure 21As shown, compared to the first photodiode and second photodiode of the image sensors 200, 300, 400, 500, and 600 according to the above embodiments, the first photodiode PD1 and the second photodiode PD2 may have different shapes. Each of pixels PX1 to PX4 may include a first floating diffuser FD1 and a second floating diffuser FD2, and the first floating diffuser FD1 and the second floating diffuser FD2 may be electrically connected to each other through wiring patterns, etc. Furthermore, according to the embodiment, in at least a portion of pixels PX1 to PX4, the pixel internal isolation layer 720 may be connected to... Figure 21 The lines extend in different diagonal directions as shown.

[0084] Next, in Figure 22 In the illustrated embodiment, the pixel isolation layer 810 disposed between pixels PX1 to PX4 in the image sensor 800 can be divided into multiple regions. (Refer to...) Figure 22 Each of pixels PX1 to PX4 can be surrounded by pixel isolation layers 810 in a second direction (X-axis direction) and a third direction (Y-axis direction), and the internal isolation layer 820 of the pixel can be connected to a pair of pixel isolation layers 810 separated from each other in the third direction. Therefore, in Figure 22 In the embodiment shown, at least a portion of the pixel isolation layer 810 can be separated and not connected to the pixel internal isolation layer 820.

[0085] Figures 23 to 26 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0086] Reference Figure 23 The image sensor 900 includes pixels PX1 to PX4, which are separated from each other by a pixel isolation layer 910. Each of pixels PX1 to PX4 includes a first photodiode PD1 and a second photodiode PD2, which are separated by an internal pixel isolation layer 920. The internal pixel isolation layer 920 may include multiple regions separated at desired and / or alternatively predetermined intervals in a third direction (Y-axis direction) intersecting a second direction (X-axis direction), which may be the orientation in which the first photodiode PD1 and the second photodiode PD2 are arranged. A floating diffusion portion FD may be disposed between the multiple regions included in the internal pixel isolation layer 920. (See attached diagram.) Figure 23 The cross-sectional view taken along cutting line VII-VII' Figure 25 The internal isolation layer 920 of the pixel may not be set on or above the floating diffuser FD.

[0087] exist Figure 23In the illustrated embodiment, the spacing between the plurality of regions (e.g., the first and second separating regions) included in the pixel internal isolation layer 920 in a portion of pixels PX1 to PX4 may be different. As an example, the spacing between the plurality of regions included in the pixel internal isolation layer 920 in the first pixel PX1 may be smaller than the spacing between the plurality of regions included in the pixel internal isolation layer 920 in the second pixel PX2. Similarly, the spacing between the plurality of regions included in the pixel internal isolation layer 920 in the third pixel PX3 may be smaller than the spacing between the plurality of regions included in the pixel internal isolation layer 920 in the first pixel PX1.

[0088] Reference shows Figure 23 The cross-sectional view taken along the cutting line VI-VI' Figure 24 The first pixel PX1 may include a green filter 902, the second pixel PX2 may include a red filter 903, and the third pixel PX3 may include a blue filter. As an example, in pixels that generate charge in response to light in the short wavelength band, the spacing between the plurality of regions included in the internal isolation layer 920 may be relatively reduced.

[0089] Reference Figure 24 The substrate 901 has a first surface on which a plurality of devices 930, wiring patterns 931, and an insulating layer 932 are disposed, and a second surface opposite to the first surface. A pixel isolation layer 910 may extend from the first surface to the second surface. An internal pixel isolation layer 920 may extend from the first surface and may have a length in a first direction (Z-axis direction) shorter than the length of the pixel isolation layer 910.

[0090] Reference Figure 26 The pixel internal isolation layer 920 may include a first pixel internal isolation layer 921 extending from a first surface of the substrate and a second pixel internal isolation layer 922 extending from a second surface of the substrate. In pixels PX1 to PX4, because the pixel internal isolation layer 920 may include multiple regions spaced upwards on the third side, a charge path can be implemented in each of pixels PX1 to PX4 for the transfer of excess charge from one of photodiodes PD1 and PD2 to the other.

[0091] According to Figure 26In the image sensor 900A of the illustrated embodiment, the second pixel internal isolation layer 922 may contact the pixel isolation layer 910 at both ends in the third direction. For example, unlike the first pixel internal isolation layer 921 which has multiple regions separated from each other in the third direction, the second pixel internal isolation layer 922 may have a shape that completely intersects each of pixels PX1 to PX4. Therefore, in the third direction, the length of the second pixel internal isolation layer 922 may be longer than the length of the first pixel internal isolation layer 921.

[0092] Figure 27 This is a schematic view of pixels included in an image sensor according to one embodiment of the inventive concept.

[0093] According to Figure 27 In the image sensor 1000 of the illustrated embodiment, pixels PX1 to PX4 included in the image sensor 1000 can be separated from each other by pixel isolation layers 1010, and the pixel-internal isolation layers 1020 in pixels PX1 to PX4 respectively may include a first pixel-internal isolation layer 1021 and a second pixel-internal isolation layer 1022. The first pixel-internal isolation layer 1021 may have the same characteristics as the referenced layer. Figures 23 to 26 The described pixel internal isolation layer 920 has a similar structure. The second pixel internal isolation layer 1022 can extend diagonally in each of pixels PX1 to PX4.

[0094] In a manner similar to the embodiments described above, for example, in accordance with reference to... Figure 18 and Figure 19 In a similar manner to the described implementation, the impurity region can be formed in a first direction (Z-axis direction) between the first pixel internal isolation layer 1021 and the second pixel internal isolation layer 1022. The impurity region can be provided as a charge path for facilitating charge transfer between the first photodiode PD1 and the second photodiode PD2.

[0095] Alternatively, in accordance with the reference Figure 26 In a similar manner to the described implementation, the first pixel internal isolation layer 1021 and the second pixel internal isolation layer 1022 can be in contact with each other in a first direction. In this case, in the first direction, the length of the first pixel internal isolation layer 1021 can be longer than the length of the first photodiode PD1 and the length of the second photodiode PD2. Furthermore, according to the embodiment, an autofocus function in the vertical direction can be implemented using a pixel signal corresponding to the charge of the first photodiode PD1 and a pixel signal corresponding to the charge of the second photodiode PD2.

[0096] Figures 28 to 33 This is a view illustrating a method for manufacturing an image sensor according to one embodiment of the inventive concept.

[0097] First, refer to Figure 28 A method for manufacturing an image sensor can begin by forming a pixel isolation layer 1110 on a substrate 1101. Furthermore, reference is made to the diagram shown... Figure 28 The cross-sectional view taken along the cutting line VIII-VIII' Figure 29 A pixel isolation layer 1110 can be formed from the first surface 1101A of the substrate 1101. For example, a trench extending from the first surface 1101A of the substrate 1101 can be formed and the formed trench can be filled with a material such as polysilicon to prepare the pixel isolation layer 1110.

[0098] Reference Figure 28 and Figure 29 The pixel isolation layer 1110 can be formed together with the internal pixel isolation layers 1120 respectively disposed within pixel regions PA1 to PA4. The internal pixel isolation layer 1120 can be formed to have a width narrower than that of the pixel isolation layer 1110, and can comprise the same material as the pixel isolation layer 1110, such as polysilicon. (See reference...) Figure 29 In the first direction (Z-axis direction), the pixel isolation layer 1110 may have a first length d1, and the pixel internal isolation layer 1120 may have a second length d2 that is shorter than the first length d1.

[0099] Next, refer to Figure 30 and Figure 31 A photodiode PD1 and PD2, along with a pixel circuit, can be formed in each of the pixel regions PA1 to PA4. The photodiodes PD1 and PD2 can be formed on both sides of the internal isolation layer 1120 of the pixel, and can be formed by a doping process, such as implanting N-type impurities. The pixel circuit can be formed on the first surface 1101A of the substrate 1101, and can include floating diffusers FD1 and FD2, multiple elements 1130, wiring patterns 1131, etc. An insulating layer 1132 covering the pixel circuit can be formed on the first surface 1101A of the substrate 1101. The insulating layer 1132 can be formed of silicon oxide, silicon nitride, etc. The floating diffusers FD1 and FD2 can be formed adjacent to the internal isolation layer 1120 of the pixel, and the elements 1130 adjacent to the floating diffusers FD1 and FD2 can be transfer transistors.

[0100] Next, refer to Figure 32 A portion of the substrate 1101 can be removed while the substrate 1101 is flipped so that the first surface 1101A faces downwards. For example, a portion of the substrate 1101 can be removed by performing a polishing process. Figure 32In the illustrated embodiment, a portion of the substrate 1101 can be removed via a polishing process to expose a surface of the pixel isolation layer 1110. Alternatively, the pixel isolation layer 1110 may not be exposed. The surface of the substrate 1101 exposed by the polishing process can be defined as a second surface 1101B.

[0101] Reference Figure 33 Color filters 1102 and 1103, a light-transmitting layer 1104, and a microlens 1105 can be formed on the second surface 1101B. The color filters 1102 and 1103 included in adjacent pixels PX1 and PX2 can transmit light of different colors. The light-transmitting layer 1104 can be shared by adjacent pixels PX1 and PX2, and a microlens 1105 for each of pixels PX1 and PX2 can be provided. Therefore, photodiodes PD1 and PD2 can be provided as a plurality of photodiodes below a microlens 1105.

[0102] Figures 34 to 41 This is a view illustrating a method for manufacturing an image sensor according to one embodiment of the inventive concept.

[0103] First, refer to Figure 34 To manufacture an image sensor, a first trench T1 and a second trench T2 can be formed in a substrate 1201 comprising semiconductor material. See also the figure below. Figure 34 A cross-sectional view taken along the cutting line IX-IX'. Figure 35 The first trench T1 and the second trench T2 can extend from the first surface 1201A of the substrate 1201 and can be formed simultaneously by an etching process. For example, the first trench T1 can have a first length d1 in a first direction (Z-axis direction) perpendicular to the first surface 1201A of the substrate 1201, and the second trench T2 can have a second length d2 shorter than the first length d1. Furthermore, in a direction parallel to the first surface 1201A, the width of the first trench T1 can be wider than the width of the second trench T2. Pixel regions PA1 to PA4 can be defined by the first trench T1, and the second trench T2 can be disposed inside each of the pixel regions PA1 to PA4.

[0104] Next, refer to Figure 36 Impurities can be injected through the second trench T2. An impurity region 1240 can be formed on or below the second trench T2 through an impurity implantation process. For example, the impurity region 1240 can be provided as a charge path between photodiodes formed on or around the sides of the second trench T2, and can include P-type impurities. According to other embodiments, the impurity region 1240 can include N-type impurities. Figure 36As shown, the second trench T2 can be formed together with the first trench T1, and an impurity implantation process can be performed to complete the impurity implantation process with relatively low energy. According to other embodiments, the impurity region 1240 can be formed to have a depth substantially equal to the depth of the bottom surface of the first trench T1.

[0105] Reference Figure 37 and Figure 38 The first trench T1 and the second trench T2 can be filled with a desired and / or alternatively predetermined material to form a pixel isolation layer 1210 and a first pixel internal isolation layer 1221, respectively. Furthermore, photodiodes PD1 and PD2 can be formed within the substrate 1201, and pixel circuitry can be formed on the first surface 1201A. The pixel circuitry may include floating diffusers FD1 and FD2, multiple elements 1230, wiring patterns 1231, etc., and may be covered by an insulating layer 1232.

[0106] The pixel isolation layer 1210 and the first pixel internal isolation layer 1221 can be formed by filling the first trench T1 and the second trench T2 with a material such as polysilicon, respectively. (See previous reference...) Figure 36 As described above, since the impurity region 1240 can be formed by performing an impurity injection process through the second trench T2, the internal isolation layer 1221 and the impurity region 1240 of the first pixel can be accurately aligned.

[0107] Reference Figure 39 After flipping the substrate 1201, a polishing process can be performed. One surface of the substrate 1201 exposed by the polishing process can be defined as the second surface 1201B. As an example, a polishing process can be performed until one surface of the pixel isolation layer 1210 forms a coplanar surface with the second surface 1201B. Therefore, as... Figure 39 As shown, the pixel isolation layer 1210 can pass through the substrate 1201.

[0108] Reference Figure 40 A second pixel internal isolation layer 1222 extending from the second surface 1201B can be formed. The second pixel internal isolation layer 1222 can be formed to be aligned with the impurity region 1240 and the first pixel internal isolation layer 1221 in a second direction (X-axis direction) and a third direction (Y-axis direction). For example, the second pixel internal isolation layer 1222 can be formed on or above the impurity region 1240, and can be provided together with the first pixel internal isolation layer 1221 to prepare the pixel internal isolation layer 1220.

[0109] exist Figure 40In the illustrated embodiment, the second pixel internal isolation layer 1222 may have the same shape as the first pixel internal isolation layer 1221. According to the embodiment, the second pixel internal isolation layer 1222 may have various shapes different from the first pixel internal isolation layer 1221. For example, unlike the first pixel internal isolation layer 1221 which extends upward in a third direction, the second pixel internal isolation layer 1222 may extend in a second direction or in a direction intersecting the second and third directions. Furthermore, according to the embodiment, the second pixel internal isolation layer 1222 may not be formed.

[0110] Next, refer to Figure 41 Color filters 1202 and 1203, a light-transmitting layer 1204, and a microlens 1205 can be formed on the substrate 1201. Color filters 1202 and 1203, respectively included in the first pixel PX1 and the second pixel PX2 adjacent to each other, can transmit light of different colors. Furthermore, a microlens 1205 can be disposed in each of pixels PX1 and PX2. Therefore, photodiodes PD1 and PD2 can be provided as multiple photodiodes below the microlens 1205.

[0111] Figure 42 and Figure 43 This is a schematic view of an electronic device including an image sensor according to one embodiment of the inventive concept.

[0112] Reference Figure 42 The electronic device 2000 may include a camera module group 2100, an application processor 2200, a power management integrated circuit (PMIC) 2300, and an external memory 2400.

[0113] Camera module group 2100 may include multiple camera modules 2100a, 2100b, and 2100c. Although the accompanying drawings show an embodiment with three (3) camera modules 2100a, 2100b, and 2100c arranged, the embodiment is not limited thereto. In one embodiment, camera module group 2100 may be modified to include only two (2) camera modules. Furthermore, in one embodiment, camera module group 2100 may be modified and implemented to include n (where n is a natural number of 4 or greater) camera modules. Additionally, in one embodiment, at least one of the multiple camera modules 2100a, 2100b, and 2100c included in camera module group 2100 may include Figures 1 to 41 The image sensor described in [the document].

[0114] The external memory 2400 may be: non-volatile memory, such as flash memory, phase-change random access memory (PRAM), magnetoresistive RAM (MRAM), resistive RAM (ReRAM), or ferroelectric RAM (FRAM); or volatile memory, such as static RAM (SRAM), dynamic RAM (DRAM), or synchronous DRAM (SDRAM).

[0115] In the following text, refer to Figure 43 The configuration of camera module 2100b will be described in more detail, but the following description can be applied equally to other camera modules 2100a and 2100c according to one embodiment.

[0116] Return to reference Figure 43 The camera module 2100b may include a prism 2105, an optical path folding element (hereinafter referred to as "OPFE") 2110, an actuator 2130, an image sensing device 2140, and a storage device 2150.

[0117] The prism 2105 may include a reflective surface 2107 of light-reflecting material to change the path of light L incident from the outside.

[0118] In one embodiment, prism 2105 can change the path of light L incident in the first direction X to a second direction Y perpendicular to the first direction X. Furthermore, prism 2105 can rotate the reflective surface 2107 of the light-reflecting material in direction A about the central axis 2106, or rotate the central axis 2106 in direction B, to change the path of light L incident in the first direction X to a second direction Y perpendicular to the first direction X. In this case, OPFE 2110 can also move in a third direction Z perpendicular to the first and second directions X and Y.

[0119] In one embodiment, as shown, the maximum rotation angle of prism 2105 can be 15 degrees or less in the positive (+) direction of direction A, and greater than 15 degrees in the negative (-) direction of direction A. The embodiments are not limited thereto.

[0120] In one embodiment, the prism 2105 can be moved by approximately 20 degrees in the positive (+) or negative (-) direction of direction B, or between 10 and 20 degrees, or between 15 and 20 degrees. In this case, the angle of movement can be the same angle in the positive (+) or negative (-) direction of direction B, or an angle that can be moved by almost the same angle within a range of approximately 1 degree.

[0121] In one embodiment, the prism 2105 can move the reflective surface 2107 of the light-reflecting material in a third direction (e.g., direction Z) parallel to the extension direction of the central axis 2106.

[0122] OPFE 2110 may include, for example, m (where m is a natural number) optical lenses. The m optical lenses can be moved in the second direction Y to change the optical zoom ratio of camera module 2100b. For example, if the base optical zoom ratio of camera module 2100b is Z, then when the m optical lenses included in OPFE 2110 are moved, the optical zoom ratio of camera module 2100b can be changed to have an optical zoom ratio of 3Z, 5Z, or higher.

[0123] Actuator 2130 can move OPFE 2110 or an optical lens (hereinafter referred to as the optical lens) to a specific position. For example, for accurate sensing, actuator 2130 can adjust the position of the optical lens to position image sensor 2142 at the focal length of the optical lens. Actuator 2130 may include an electric motor.

[0124] Image sensing device 2140 may include image sensor 2142, control logic 2144, and memory 2146. Image sensor 2142 can sense an image of the object to be sensed using light L provided through an optical lens. Control logic 2144 can control the overall operation of camera module 2100b. For example, control logic 2144 can control the operation of camera module 2100b according to control signals provided through control signal line CSLb.

[0125] Memory 2146 may store information required for the operation of camera module 2100b, such as calibration data 2147. Calibration data 2147 may include information required by camera module 2100b to generate image data using externally provided light L. Calibration data 2147 may include, for example, information about the aforementioned rotation degrees, information about the focal length, information about the optical axis, etc. When camera module 2100b is implemented as a multi-state camera where the focal length changes according to the position of the optical lens, calibration data 2147 may include the focal length value for each position (or state) of the optical lens and information related to autofocus.

[0126] Storage device 2150 can store image data sensed by image sensor 2142. Storage device 2150 can be disposed outside image sensing device 2140 and can be implemented in a stacked manner with the sensor chip constituting image sensing device 2140. In one embodiment, storage device 2150 can be implemented as electrically erasable programmable read-only memory (EEPROM), but the implementation is not limited thereto.

[0127] Refer to together Figure 42 and Figure 23In one embodiment, multiple camera modules 2100a, 2100b, and 2100c may each include an actuator 2130. Therefore, depending on the operation of the actuators 2130 included therein, the multiple camera modules 2100a, 2100b, and 2100c may each include the same or different calibration data 2147.

[0128] In one embodiment, one of the multiple camera modules 2100a, 2100b and 2100c (e.g. 2100b) may be a folding lens type camera module including prism 2105 and OPFE 2110 as described above, and the remaining (multiple) camera modules (e.g. 2100a or 2100c) may be vertical type camera modules without prism 2105 and OPFE 2110, but the implementation is not limited to this.

[0129] In one embodiment, one of the multiple camera modules 2100a, 2100b, and 2100c (e.g., 2100c) may be a vertical depth camera used to extract depth information using, for example, infrared (IR). In this case, the application processor 2200 may merge image data provided from the depth camera with image data provided from another camera module (e.g., 2100a or 2100b) to generate a 3D depth image.

[0130] In one embodiment, at least two camera modules (e.g., 2100a and 2100b) of the plurality of camera modules 2100a, 2100b and 2100c may have different fields of view (e.g., field angles). In this case, for example, the optical lenses of the at least two camera modules (e.g., 2100a and 2100b) of the plurality of camera modules 2100a, 2100b and 2100c may be different from each other, but are not limited thereto.

[0131] Furthermore, in one embodiment, the field of view of each of the plurality of camera modules 2100a, 2100b, and 2100c may be different. In this case, the optical lenses included in each of the plurality of camera modules 2100a, 2100b, and 2100c may also be different from each other, but are not limited thereto.

[0132] In one embodiment, each of the plurality of camera modules 2100a, 2100b and 2100c may be arranged to be physically separate from each other. For example, the sensing area of ​​an image sensor 2142 may not be divided and used by the plurality of camera modules 2100a, 2100b and 2100c, but may be provided in an independent image sensor 2142 within each of the plurality of camera modules 2100a, 2100b and 2100c.

[0133] Return to reference Figure 42The application processor 2200 may include an image processing device 2210, a memory controller 2220, and internal memory 2230. The application processor 2200 may be implemented separately from the plurality of camera modules 2100a, 2100b, and 2100c. For example, the application processor 2200 and the plurality of camera modules 2100a, 2100b, and 2100c may be implemented separately from each other as separate semiconductor chips.

[0134] The image processing apparatus 2210 may include a plurality of sub-image signal processors (also referred to as sub-processors) 2212a, 2212b and 2212c, an image generator 2214 and a camera module controller 2216.

[0135] The image processing apparatus 2210 may include a plurality of sub-image signal processors 2212a, 2212b and 2212c corresponding to the number of camera modules 2100a, 2100b and 2100c.

[0136] Image data generated from each of camera modules 2100a, 2100b, and 2100c can be provided to the corresponding sub-image signal processors 2212a, 2212b, and 2212c via image signal lines ISLa, ISLb, and ISLc, which are separate from each other. For example, image data generated from camera module 2100a can be provided to sub-image signal processor 2212a via image signal line ISLa, image data generated from camera module 2100b can be provided to sub-image signal processor 2212b via image signal line ISLb, and image data generated from camera module 2100c can be provided to sub-image signal processor 2212c via image signal line ISLc. This image data transmission can be performed using, for example, a Camera Serial Interface (CSI) based on the Mobile Industrial Processor Interface (MIPI), but the implementation is not limited to this.

[0137] In one embodiment, the sub-image signal processor can be configured to correspond to multiple camera modules. For example, sub-image signal processors 2212a and 2212c may not be implemented separately from each other as shown, but may be implemented as integrated into a single sub-image signal processor, and image data provided from camera modules 2100a and 2100c may be selected by a selection element (e.g., a multiplexer) and then provided to the integrated sub-image signal processor.

[0138] Image data provided to each of the sub-image signal processors 2212a, 2212b, and 2212c can be provided to the image generator 2214. The image generator 2214 can generate an output image based on the image generation information or pattern signal using the image data provided from each of the sub-image signal processors 2212a, 2212b, and 2212c.

[0139] Specifically, image generator 2214 can generate an output image by merging at least a portion of image data generated from camera modules 2100a, 2100b, and 2100c, which have different field of view angles, based on image generation information or a mode signal. Furthermore, image generator 2214 can generate an output image by selecting any one of the image data generated from camera modules 2100a, 2100b, and 2100c, which have different field of view angles, based on image generation information or a mode signal.

[0140] In one embodiment, the image generation information may include a zoom signal or a zoom factor. Furthermore, in one embodiment, the mode signal may be, for example, a signal based on a user-selected mode.

[0141] When the image generation information is a zoom signal (e.g., zoom factor) and each of camera modules 2100a, 2100b, and 2100c has a different field of view (e.g., field of view angle), the image generator 2214 can operate differently depending on the type of zoom signal. For example, when the zoom signal is a first signal, after merging the image data output from camera module 2100a and the image data output from camera module 2100c, the merged image signal and the image data output from camera module 2100b that is not used for merging can be used to generate an output image. When the zoom signal is a second signal different from the first signal, the image generator 2214 may not perform such image data merging and can select any one of the image data output from each of camera modules 2100a, 2100b, and 2100c to create an output image. The implementation is not limited to this, and the method of processing image data can be modified and executed as needed.

[0142] In one embodiment, the image generator 2214 may receive multiple image data with different exposure time points from at least one of a plurality of sub-image signal processors 2212a, 2212b and 2212c, and may process high dynamic range (HDR) for the plurality of image data to generate merged image data with increased dynamic range.

[0143] The camera module controller 2216 can provide control signals to each of the camera modules 2100a, 2100b, and 2100c. The control signals generated from the camera module controller 2216 can be provided to the corresponding camera modules 2100a, 2100b, and 2100c via separate control signal lines CSLa, CSLb, and CSLc.

[0144] Any one of the multiple camera modules 2100a, 2100b, and 2100c can be designated as the master camera (e.g., 2100b) based on image generation information including zoom signals or mode signals, and the remaining camera modules (e.g., 2100a and 2100c) can be designated as slave cameras. Such information can be included in control signals and provided to the corresponding camera modules 2100a, 2100b, and 2100c via separate control signal lines CSLa, CSLb, and CSLc.

[0145] The camera module can be configured to operate as a master or slave device based on the zoom factor or operating mode signal. For example, when the field of view of camera module 2100a is wider than that of camera module 2100b and the zoom factor indicates a low zoom ratio, camera module 2100b can operate as the master device, and camera module 2100a can operate as the slave device. When the zoom factor indicates a high zoom ratio, camera module 2100a can operate as the master device, and camera module 2100b can operate as the slave device.

[0146] In one embodiment, the control signals provided from the camera module controller 2216 to each of the camera modules 2100a, 2100b, and 2100c may include a synchronization enable signal. For example, when camera module 2100b is the master camera and camera modules 2100a and 2100c are slave cameras, the camera module controller 2216 may send a synchronization enable signal to camera module 2100b. Camera module 2100b, receiving this synchronization enable signal, may generate a synchronization signal based on the synchronization enable signal and may send the generated synchronization signal to camera modules 2100a and 2100c via the synchronization signal line SSL. Camera modules 2100b, 2100a, and 2100c may synchronize with this synchronization signal to send image data to the application processor 2200.

[0147] In one embodiment, the control signals provided from the camera module controller 2216 to the plurality of camera modules 2100a, 2100b, and 2100c may include mode information based on a mode signal. Based on this mode information, the plurality of camera modules 2100a, 2100b, and 2100c may operate in a first operating mode and a second operating mode related to the sensing rate.

[0148] In the first operating mode, multiple camera modules 2100a, 2100b, and 2100c can generate image signals at a first rate (e.g., generate image signals with a first frame rate), encode the generated image signals at a second rate higher than the first rate (e.g., encode image signals with a second frame rate higher than the first frame rate), and send the encoded image signals to the application processor 2200. In this case, the second rate can be 30 times or less than the first rate.

[0149] Application processor 2200 can store the transmitted image signal, such as an encoded image signal, in internal memory 2230 or in external memory 2400. It can then read the encoded image signal from either internal memory 2230 or external memory 2400, decode the read image signal, and display image data generated based on the decoded image signal. For example, a corresponding sub-image signal processor among the plurality of sub-image signal processors 2212a, 2212b, and 2212c of image processing device 2210 can decode the read image signal and perform image processing on the decoded image signal.

[0150] In the second operating mode, multiple camera modules 2100a, 2100b, and 2100c can generate image signals at a third rate lower than the first rate (e.g., generate image signals with a third frame rate lower than the first frame rate), and can send the image signals to the application processor 2200. The image signals provided to the application processor 2200 can be uncoded signals. The application processor 2200 can perform image processing on the received image signals, or can store the received image signals in internal memory 2230 or external memory 2400.

[0151] The PMIC 2300 can supply power, for example, a power supply voltage, to each of the multiple camera modules 2100a, 2100b, and 2100c. For example, under the control of the application processor 2200, the PMIC 2300 can supply a first power to camera module 2100a via power signal line PSLa, a second power to camera module 2100b via power signal line PSLb, and a third power to camera module 2100c via power signal line PSLc.

[0152] The PMIC 2300 can generate power corresponding to each of the plurality of camera modules 2100a, 2100b, and 2100c in response to a power control signal PCON from the application processor 2200, and can also adjust the power level. The power control signal PCON can include a power adjustment signal for each operating mode of the plurality of camera modules 2100a, 2100b, and 2100c. For example, the operating mode can include a low-power mode. In this case, the power control signal PCON can include information about the camera module operating in the low-power mode and the power level to be set. The power levels supplied to each of the plurality of camera modules 2100a, 2100b, and 2100c can be the same or different from each other. Furthermore, the power levels can be changed dynamically.

[0153] According to one embodiment of the inventive concept, an image sensor may include autofocus pixels, and the autofocus pixels may include a first photodiode and a second photodiode separated from each other by an internal pixel isolation layer. The internal pixel isolation layer may include a first internal pixel isolation layer and a second internal pixel isolation layer formed of different materials. The internal pixel isolation layer may extend from a first surface of a substrate together with the pixel isolation layers between pixels, and may provide a charge path through which charge can move between the first photodiode and the second photodiode. Therefore, alignment errors between the pixel isolation layers and the internal pixel isolation layers can be reduced and / or minimized, and the pixel capacitance can be improved.

[0154] One or more of the elements disclosed above may include or be implemented in processing circuitry, such as: hardware, including logic circuitry; hardware / software combination, such as a processor running software; or a combination thereof. More specifically, the processing circuitry may include, but is not limited to, a central processing unit (CPU), an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field-programmable gate array (FPGA), a system-on-a-chip (SoC), a programmable logic unit, a microprocessor, an application-specific integrated circuit (ASIC), etc.

[0155] The various features and effects of the inventive concept are not limited to those described above, and can be more easily understood in the process of describing specific embodiments of the inventive concept.

[0156] While exemplary embodiments have been described and illustrated above, it will be apparent to those skilled in the art that modifications and variations may be made without departing from the scope of the inventive concept as defined by the appended claims.

[0157] This application claims the benefit of Korean Patent Application No. 10-2020-0100044, filed on August 10, 2020, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

Claims

1. An image sensor, comprising: A pixel array includes a substrate, a plurality of pixels arranged in a direction parallel to the upper surface of the substrate, and a pixel isolation layer between adjacent pixels in the plurality of pixels, each of the plurality of pixels including at least one photodiode and pixel circuitry below the at least one photodiode. as well as The logic circuit is configured to acquire pixel signals from the plurality of pixels. The pixel array includes at least one autofocus pixel. The at least one autofocus pixel includes a first photodiode, a second photodiode, an internal pixel isolation layer between the first photodiode and the second photodiode, and a microlens on the first photodiode and the second photodiode. The pixel internal isolation layer includes a first pixel internal isolation layer and a second pixel internal isolation layer. The first pixel internal isolation layer and the second pixel internal isolation layer are separated from each other in a first direction. The first direction is perpendicular to the upper surface of the substrate, and The material of the isolation layer inside the first pixel is different from the material of the isolation layer inside the second pixel. Specifically, in a second direction parallel to the upper surface of the substrate and perpendicular to each other, and in a third direction, the internal isolation layer of the second pixel does not overlap with the first photodiode and the second photodiode. Wherein, each of the first photodiode and the second photodiode has an upper surface, the upper surface being located between the inner isolation layer of the first pixel and the inner isolation layer of the second pixel in the first direction, and The impurity region for providing a charge transfer path between the first photodiode and the second photodiode is disposed in the first direction between the inner isolation layer of the first pixel and the inner isolation layer of the second pixel.

2. The image sensor according to claim 1, wherein The first pixel's internal isolation layer extends from the pixel circuit and includes polysilicon, and The internal isolation layer of the second pixel includes an insulating material.

3. The image sensor according to claim 2, wherein The pixel circuit is configured to apply a negative voltage to the internal isolation layer of the first pixel while the logic circuit acquires the pixel signal from the plurality of pixels.

4. The image sensor according to claim 2, wherein, In a direction parallel to the upper surface of the substrate, the length of the internal isolation layer of the first pixel is different from the length of the internal isolation layer of the second pixel.

5. The image sensor according to claim 4, wherein, In one direction, the internal isolation layer of the first pixel is separated from the pixel isolation layer.

6. The image sensor according to claim 1, wherein The impurity region contains P-type impurities.

7. The image sensor according to claim 1, wherein The pixel isolation layer includes a first pixel isolation layer and a second pixel isolation layer. The first pixel isolation layer extends from the pixel circuit and includes a first material. The second pixel isolation layer extends from the first pixel isolation layer and includes a second material, and The second material is different from the first material.

8. The image sensor according to claim 7, wherein The first pixel's internal isolation layer includes the first material, and The second pixel's internal isolation layer comprises the second material.

9. The image sensor of claim 7, wherein the reflectivity of the second material is higher than that of the first material.

10. An image sensor, comprising: A substrate having a first surface and a second surface opposite to the first surface; A pixel array includes a plurality of pixels and pixel isolation layers between adjacent pixels, the pixel isolation layers extending from the first surface of the substrate to a second surface of the substrate in a first direction perpendicular to the first surface. Each of the plurality of pixels includes at least one photodiode inside the substrate and a pixel circuit having a plurality of elements on the first surface; as well as The logic circuit is configured to acquire pixel signals from the plurality of pixels. The pixel array includes at least one autofocus pixel. The at least one autofocus pixel includes a first photodiode, a second photodiode, an internal pixel isolation layer extending from the first surface in the first direction between the first photodiode and the second photodiode, and a microlens on the second surface. The pixel internal isolation layer includes a first pixel internal isolation layer extending from the first surface and a second pixel internal isolation layer extending from the second surface. The first pixel internal isolation layer and the second pixel internal isolation layer have different shapes in a plane parallel to the first surface. Specifically, in a second direction parallel to the first surface of the substrate and perpendicular to each other, and in a third direction, the internal isolation layer of the second pixel does not overlap with the first photodiode and the second photodiode. Wherein, each of the first photodiode and the second photodiode has an upper surface, the upper surface being located between the inner isolation layer of the first pixel and the inner isolation layer of the second pixel in the first direction, and The impurity region for providing a charge transfer path between the first photodiode and the second photodiode is disposed in the first direction between the inner isolation layer of the first pixel and the inner isolation layer of the second pixel.

11. The image sensor according to claim 10, wherein, In the plane parallel to the first surface, the first pixel internal isolation layer extends in the second direction, and the second pixel internal isolation layer extends upward in a third direction different from the second direction.

12. The image sensor according to claim 10, in, In the plane parallel to the first surface, the first pixel internal isolation layer and the second pixel internal isolation layer extend in the second direction, and In the second direction, the length of the isolation layer inside the first pixel is different from the length of the isolation layer inside the second pixel.

13. The image sensor according to claim 12, wherein, In the second direction, the length of the isolation layer inside the first pixel is shorter than the length of the isolation layer inside the second pixel.

14. The image sensor according to claim 10, wherein, In the plane parallel to the first surface, the width of the internal isolation layer of the pixel is narrower than the width of the pixel isolation layer.

15. The image sensor according to claim 10, wherein The impurity region contains P-type impurities.

16. The image sensor according to claim 10, wherein The pixel isolation layer includes a first pixel isolation layer and a second pixel isolation layer. The first pixel isolation layer extends from the first surface. The second pixel isolation layer extends from the second surface in the first direction and is connected to the first pixel isolation layer, and In the first direction, the length of the second pixel isolation layer is shorter than the length of the first pixel isolation layer.

17. The image sensor of claim 16, wherein the reflectivity of the internal isolation layer of the second pixel is higher than the reflectivity of the internal isolation layer of the first pixel.

18. An image sensor, comprising: A substrate having a first surface and a second surface opposite to the first surface; A pixel array includes a plurality of pixels and a pixel isolation layer between adjacent pixels in the plurality of pixels, the pixel isolation layer extending from the first surface in a first direction perpendicular to the first surface, each of the plurality of pixels including at least one photodiode and a pixel circuit, the pixel circuit having a plurality of elements on the first surface; as well as The logic circuit is configured to acquire pixel signals from the plurality of pixels. The pixel array includes at least one autofocus pixel. The autofocus pixel includes a first photodiode and a second photodiode spaced apart from each other in a second direction parallel to the first surface, an internal pixel isolation layer extending from the first surface in the first direction between the first photodiode and the second photodiode, and a microlens on the second surface. The pixel-internal isolation layer has a first vertical surface and a second vertical surface that extend in the first direction and intersect the second direction in opposite directions. At least one of the first vertical surface and the second vertical surface is separated from the pixel isolation layer. The pixel internal isolation layer includes a first separation region and a second separation region. The first dividing area and the second dividing area are separated from each other in the direction of the third party.

19. The image sensor of claim 18, wherein a portion of the substrate is in at least one of the space between the first vertical surface and the pixel isolation layer and the space between the second vertical surface and the pixel isolation layer.

20. The image sensor of claim 18, wherein The floating diffusion node is located between the first dividing zone and the second dividing zone.

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