image sensor

Abstract

This application provides an image sensor, comprising: at least one photosensitive unit, the photosensitive unit having at least two photosensitive layers stacked but not completely overlapping, wherein in one photosensitive unit, an area of ​​each photosensitive layer not overlapping with other photosensitive layers is used to set electrode lines, and the at least two photosensitive layers have different photosensitive component contents. By setting at least two partially overlapping photosensitive layers in each photosensitive unit, and ensuring that the at least two photosensitive layers have different photosensitive component contents, this application expands the range of light wavelengths sensed by each photosensitive unit, thereby enabling the recording of more image details, generating high dynamic range images, and providing a visual effect close to the real environment. Furthermore, in each photosensitive unit, the electrode lines are located in the area of ​​each photosensitive layer not overlapping with other photosensitive layers, thus eliminating the need to reduce the photosensitive area of ​​the photosensitive layers to accommodate the electrode lines, thereby increasing the photosensitive area of ​​the photosensitive layers and improving the dynamic range of the image sensor.

Description

Technical Field

[0001] This application relates to the field of image processing technology, and more specifically to an image sensor. Background Technology

[0002] Image sensors are a crucial component of camera devices. Current technologies achieve image sensing by stacking multiple color photosensitive layers. However, in shooting environments with a wide brightness range, existing image sensors cannot generate high dynamic range images, thus failing to provide sufficient image detail and reproduce the visual effects of the real environment.

[0003] However, in existing overlay methods, the utilization rate of the photosensitive area of ​​the photosensitive layer is low. Therefore, how to balance increasing the photosensitive area of ​​the photosensitive layer and improving the dynamic range of the image sensor has become an urgent problem to be solved. Summary of the Invention

[0004] To address the aforementioned technical problems, this application is proposed. An embodiment of this application provides an image sensor.

[0005] In a first aspect, one embodiment of this application provides an image sensor, which includes: at least one photosensitive unit, the photosensitive unit having at least two photosensitive layers stacked but not completely overlapping, in a photosensitive unit, the area of ​​each photosensitive layer that does not overlap with other photosensitive layers is used to set electrode lines, and the photosensitive component content of the at least two photosensitive layers is different.

[0006] In some implementations of the first aspect, at least two photosensitive layers have equal areas.

[0007] In some implementations of the first aspect, the photosensitive component includes an indium-containing gallium nitride-based compound, and the photosensitive component content of at least two photosensitive layers is different, including: the indium component content of at least two photosensitive layers is different.

[0008] In some implementations of the first aspect, at least two photosensitive layers sense light of the same color, and the difference between the indium content of the at least two photosensitive layers is less than or equal to 4%.

[0009] In some implementations of the first aspect, the at least two photosensitive layers include an outer photosensitive layer that is closest to the external light source, the indium content of the outer photosensitive layer is greater than the minimum indium content of the photosensitive layers other than the outer photosensitive layer among the at least two photosensitive layers, and the indium content of the outer photosensitive layer is less than the maximum indium content of the photosensitive layers other than the outer photosensitive layer among the at least two photosensitive layers.

[0010] In some implementations of the first aspect, at least two photosensitive layers sense light of different colors, and the photosensitive unit has three photosensitive layers stacked but not completely overlapping, including a red photosensitive layer for sensing red light, a green photosensitive layer for sensing green light, and a blue photosensitive layer for sensing blue light, wherein the indium content of the red photosensitive layer, the indium content of the green photosensitive layer, and the indium content of the blue photosensitive layer decrease in that order.

[0011] In some implementations of the first aspect, a green photosensitive layer is stacked on the side of the red photosensitive layer away from the external light source, and / or a blue photosensitive layer is stacked on the side of the red photosensitive layer away from the external light source.

[0012] In some implementations of the first aspect, at least two photosensitive layers are rotated and offset about the center of the photosensitive unit, so that the at least two photosensitive layers do not completely overlap.

[0013] In some implementations of the first aspect, the image sensor further includes a charge storage component electrically connected to each photosensitive layer, wherein the charge storage component is electrically connected to the electrode lines and is electrically insulated from each other.

[0014] In some implementations of the first aspect, the image sensor further includes: a plurality of photosensitive units, and an isolation member disposed between two adjacent photosensitive units, the isolation member being used to electrically insulate adjacent photosensitive units from each other.

[0015] This application provides an image sensor comprising: at least one photosensitive unit, the photosensitive unit having at least two photosensitive layers stacked but not completely overlapping, wherein in one photosensitive unit, an area of ​​each photosensitive layer not overlapping with other photosensitive layers is used to set electrode lines, and the at least two photosensitive layers have different photosensitive component contents. By setting at least two partially overlapping photosensitive layers in each photosensitive unit, and ensuring that the at least two photosensitive layers have different photosensitive component contents, this application expands the range of light wavelengths sensed by each photosensitive unit, thereby enabling the recording of more image details, generating high dynamic range images, and providing a visual effect close to the real environment. Furthermore, in each photosensitive unit, the electrode lines are located in the area of ​​each photosensitive layer not overlapping with other photosensitive layers, thus eliminating the need to reduce the photosensitive area of ​​the photosensitive layers for setting the electrode lines. Therefore, the image sensor provided in this application increases the photosensitive area of ​​the photosensitive layers, thereby improving the dynamic range of the image sensor. Attached Figure Description

[0016] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0017] Figure 1 The diagram shown is a schematic diagram of the structure of a photosensitive unit provided in an exemplary embodiment of this application.

[0018] Figure 2 The diagram shown is an enlarged view of the non-overlapping region provided in an exemplary embodiment of this application.

[0019] Figure 3 The diagram shown is a schematic diagram of the structure of a photosensitive unit provided in another exemplary embodiment of this application.

[0020] Figure 4 The image shown is an exploded view of the photosensitive layer in a photosensitive unit.

[0021] Figure 5 The diagram shown is a schematic diagram of the structure of a photosensitive unit provided in another exemplary embodiment of this application.

[0022] Figure 6 The diagram shown is a schematic diagram of the structure of a photosensitive unit provided in another exemplary embodiment of this application.

[0023] Figure 7 The diagram shown is a schematic diagram of the structure of a photosensitive unit provided in another exemplary embodiment of this application.

[0024] Figure 8 As shown Figure 3 Cross-sectional view along AA'.

[0025] Figure 9 The diagram shown is a partially enlarged structural schematic of an isolation component provided in an exemplary embodiment of this application.

[0026] Reference numerals: Photosensitive unit 100; First photosensitive layer 110; Second photosensitive layer 120; Third photosensitive layer 130; Electrode line 200; Non-overlapping area W110; Red photosensitive unit R100; Green photosensitive unit G100; Blue photosensitive unit B100; Red photosensitive layer R140; Green photosensitive layer G150; Blue photosensitive layer B160; Center point O of photosensitive unit; First charge storage component 110'; Second charge storage component 120'; Third charge storage component 130'; Isolation component 300; Metal part 310; Insulating layer 320; Incident ray P; Reflected ray P'. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed description. Those skilled in the art should understand that this application can be implemented without certain specific details. In some instances, methods, means, components, and circuits well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.

[0029] Figure 1 The diagram shown is a schematic representation of the structure of a photosensitive unit provided in an exemplary embodiment of this application. Figure 1 As shown, the image sensor provided in this application embodiment includes: at least one photosensitive unit 100, the photosensitive unit 100 having at least two photosensitive layers stacked but not completely overlapping, in a photosensitive unit 100, the area of ​​each photosensitive layer that does not overlap with other photosensitive layers is used to set electrode lines 200, and the photosensitive component content of the at least two photosensitive layers is different.

[0030] Specifically, such as Figure 1 As shown in the illustration, the image sensor provided in this application embodiment illustrates four photosensitive units 100. For each photosensitive unit 100, the photosensitive unit 100 has two photosensitive layers that are stacked but not completely overlapped, namely a first photosensitive layer 110 and a second photosensitive layer 120.

[0031] Figure 2 The diagram shown is an enlarged view of a non-overlapping region provided in an exemplary embodiment of this application. Figure 2 As shown, the non-overlapping area W110 refers to the area where each photosensitive layer does not overlap with other photosensitive layers (e.g., ...). Figure 2(The area selected by the dashed line). Specifically, in a photosensitive unit 100, the first photosensitive layer 110 has a portion that does not overlap with the second photosensitive layer 120, and the second photosensitive layer 120 also has a portion that does not overlap with the first photosensitive layer 110. These two portions constitute the non-overlapping area of ​​the first photosensitive layer 110 and the second photosensitive layer 120. The non-overlapping area W110 is used to set the electrode lines 200, that is, the electrode lines 200 are set in the area of ​​each photosensitive layer that does not overlap with other photosensitive layers. In each photosensitive unit 100, the electrode lines 200 are set in the area of ​​each photosensitive layer that does not overlap with other photosensitive layers, thereby eliminating the need to reduce the photosensitive area of ​​the photosensitive layer to set the electrode lines 200 and improving the utilization rate of the photosensitive area. It should be noted that the electrode lines can be actual electrode lines or structures that achieve electrical connection between the electrode and the photosensitive layer.

[0032] It should be noted that, as Figure 1 As shown, the four photosensitive units 100 are represented by four dashed boxes, which are only used to illustrate the existence of four photosensitive units. It is not necessary for there to be a specific physical boundary between two photosensitive units 100.

[0033] In one embodiment of this application, in a photosensitive unit 100, the photosensitive component contents of the first photosensitive layer 110 and the second photosensitive layer 120 are different, resulting in different sensing light wavelength ranges corresponding to the two photosensitive layers. For example, the sensing light wavelength range corresponding to the second photosensitive layer 120 may not cover the sensing light wavelength range corresponding to the first photosensitive layer 110. Therefore, the sensing light wavelength range not covered by the first photosensitive layer 110 can be added to the sensing light wavelength range corresponding to the first photosensitive layer 110, thereby expanding the sensing light wavelength range of each photosensitive unit 100, improving the dynamic range of the image sensor, enabling the recording of more image details, generating high dynamic range images, and providing a visual effect close to the real environment.

[0034] In order to improve the utilization rate of the photosensitive area and further improve the dynamic range of the image sensor, this application... Figure 1 This application extends from the embodiments shown. Figure 3 The illustrated embodiment will be described in detail below. Figure 3 The illustrated embodiments and Figure 1 The differences between the embodiments shown are not repeated here, and the similarities are not repeated here.

[0035] Figure 3 The diagram shown is a schematic representation of the structure of a photosensitive unit provided in another exemplary embodiment of this application. Specifically, as... Figure 3As shown in the illustration, the image sensor provided in this application embodiment illustrates four photosensitive units 100. Each photosensitive unit 100 has three photosensitive layers stacked but not completely overlapping: a first photosensitive layer 110, a second photosensitive layer 120, and a third photosensitive layer 130. The non-overlapping areas of the first photosensitive layer 110, the second photosensitive layer 120, and the third photosensitive layer 130 are used to set electrode lines 200; that is, the electrode lines 200 are set in the areas of each photosensitive layer that do not overlap with other photosensitive layers (non-overlapping areas W110). In each photosensitive unit 100, the electrode lines 200 are set in the areas of each photosensitive layer that do not overlap with other photosensitive layers, thereby eliminating the need to reduce the photosensitive area of ​​the photosensitive layers and improving the utilization rate of the photosensitive area. In one embodiment of this application, in a photosensitive unit 100, the photosensitive component contents of the first photosensitive layer 110, the second photosensitive layer 120, and the third photosensitive layer 130 are different, thus the sensing light wavelength ranges corresponding to the three photosensitive layers are different. For example, the sensing light wavelength range corresponding to the second photosensitive layer 120 may not cover the sensing light wavelength range corresponding to the first photosensitive layer 110, and the sensing light wavelength range corresponding to the third photosensitive layer 130 may not cover the sensing light wavelength ranges corresponding to the first and second photosensitive layers 110. Therefore, the sensing light wavelength range of each photosensitive unit 100 can be expanded multiple times based on the sensing light wavelength range corresponding to the first photosensitive layer 110, improving the dynamic range of the image sensor, enabling the recording of more image details, generating high dynamic range images, and providing a visual effect close to the real environment.

[0036] Specifically, such as Figures 1 to 3 As shown, the first photosensitive layer 110, the second photosensitive layer 120, and the third photosensitive layer 130 are all hexagonal in shape, with equal side lengths, and can be rotated out of alignment around the center point O. Optionally, in a photosensitive unit 100, the photosensitive layer includes at least one of the following shapes: polygonal, elliptical, or circular. Optionally, in an image sensor, the photosensitive layer includes one or more combinations of the following shapes: polygonal, elliptical, or circular.

[0037] In one embodiment of this application, at least two photosensitive layers have equal areas. Specifically, as shown... Figure 3 As shown, the side lengths of the first photosensitive layer 110, the second photosensitive layer 120, and the third photosensitive layer 130 are equal, thus the areas of the first photosensitive layer 110, the second photosensitive layer 120, and the third photosensitive layer 130 are equal.

[0038] In existing technologies, taking two adjacent photosensitive layers as an example, to set electrode lines, the area of ​​the photosensitive layer closer to the charge storage device is typically smaller than the area of ​​the photosensitive layer farther from the charge storage device. Specifically, in order to set electrode lines in the photosensitive layer farther from the charge storage device, it is necessary to reduce the area of ​​the photosensitive layer closer to the charge storage device. This is usually done by etching the photosensitive layer closer to the charge storage device to create a non-overlapping region between the two adjacent photosensitive layers, and the electrode lines are set in this non-overlapping region. This is a method of sacrificing the area of ​​the photosensitive layer to set electrode lines.

[0039] In one embodiment of this application, since the electrode line 200 is disposed in the non-overlapping region W110, and this non-overlapping region W110 is not formed by shrinking the photosensitive layer, it is not necessary to reduce the photosensitive area of ​​the photosensitive layer to accommodate the electrode line 200, thereby improving the utilization rate of the photosensitive area. Therefore, the areas of the first photosensitive layer 110, the second photosensitive layer 120, and the third photosensitive layer 130 are equal. The image sensor provided in this embodiment increases the photosensitive area of ​​the photosensitive layer, thereby improving the dynamic range of the image sensor.

[0040] Figure 4 The image shown is an exploded view of the photosensitive layer within a single photosensitive unit. Figure 4 As shown, the first photosensitive layer 110, the second photosensitive layer 120 and the third photosensitive layer 130 are parallel to each other, and the second photosensitive layer 120 is rotated at a certain angle relative to the first photosensitive layer 110, and the third photosensitive layer 130 is rotated at another angle relative to the first photosensitive layer 110, so that the first photosensitive layer 110, the second photosensitive layer 120 and the third photosensitive layer 130 do not completely overlap.

[0041] Figure 5 The diagram shown is a schematic representation of the structure of a photosensitive unit provided in another exemplary embodiment of this application. Figure 3 This application extends from the embodiments shown. Figure 5 The illustrated embodiment will be described in detail below. Figure 5 The illustrated embodiments and Figure 3 The differences between the illustrated embodiments are not repeated here, and the similarities are not. Figure 5 As shown, the first photosensitive layer 110, the second photosensitive layer 120 and the third photosensitive layer 130 are all elliptical in shape. The major axes of the three photosensitive layers are equal and the minor axes of the three photosensitive layers are also equal. The three photosensitive layers can be rotated and offset about the center point O.

[0042] In one embodiment of this application, the photosensitive component includes an indium-containing gallium nitride-based compound, and the photosensitive component content of at least two photosensitive layers is different, including: the indium component content of at least two photosensitive layers is different. Exemplarily, the indium component content refers to the percentage of the amount of indium element relative to the sum of the amounts of all positively charged elements. Specifically, by adjusting the indium component content of the first photosensitive layer 110, the second photosensitive layer 120, and the third photosensitive layer 130 to be different, the first photosensitive layer 110, the second photosensitive layer 120, and the third photosensitive layer 130 respectively sense light within different wavelength ranges, thereby improving the dynamic range of the image sensor and generating a high dynamic range image.

[0043] In one embodiment of this application, at least two photosensitive layers sense light of the same color, and the difference between the indium content of the at least two photosensitive layers is less than or equal to 4%.

[0044] Specifically, such as Figure 1 and Figure 3 As shown, the photosensitive units 100 in the first row and first column and the photosensitive units 100 in the second row and second column are both red photosensitive units R100 that sense red light; the photosensitive unit 100 in the first row and second column is a blue photosensitive unit B100 that senses blue light; and the photosensitive unit 100 in the second row and first column is a green photosensitive unit G100 that senses green light. Optionally, as... Figure 3 The four photosensitive units 100 shown constitute a pixel group. The reason a pixel group includes two red photosensitive units R100, one green photosensitive unit G100, and one blue photosensitive unit B100 is that the red photosensitive unit R100, corresponding to a high indium content, has a lower epitaxial crystal quality during fabrication, resulting in lower photosensitivity than both the green and blue photosensitive units G100. Furthermore, different indium content results in different wavelengths of sensed light. By setting up photosensitive units 100 capable of sensing red, green, and blue colors within a pixel group, the entire visible light spectrum can be covered. When the image sensor senses external light, it can directly record color images across the entire visible light wavelength range in the environment. Combined with at least two photosensitive layers for each photosensitive unit 100, a high dynamic range image is generated, providing a visual effect close to the real environment.

[0045] Among them, such as Figure 3As shown, taking the red photosensitive unit R100 as an example, the first photosensitive layer 110 is disposed at the position closest to the external light source, the second photosensitive layer 120 is disposed on the side of the first photosensitive layer 110 away from the external light source, and the third photosensitive layer 130 is disposed on the side of the second photosensitive layer 120 away from the external light source. All three photosensitive layers in the red photosensitive unit R100 sense red light. The difference between the indium content of the first photosensitive layer 110 and the indium content of the second photosensitive layer 120 is less than or equal to 4%, and / or the difference between the indium content of the second photosensitive layer 120 and the indium content of the third photosensitive layer 130 is less than or equal to 4%. For example, the indium content of the first photosensitive layer 110 is 0.46%, the indium content of the second photosensitive layer 120 is 0.50%, and the indium content of the third photosensitive layer 130 is 0.54%. Taking the green photosensitive unit G100 as an example, the indium content of the first photosensitive layer 110 is 0.21%, the indium content of the second photosensitive layer 120 is 0.25%, and the indium content of the third photosensitive layer 130 is 0.29%. Taking the blue photosensitive unit B100 as an example, the indium content of the first photosensitive layer 110 is 0.01%, the indium content of the second photosensitive layer 120 is 0.05%, and the indium content of the third photosensitive layer 130 is 0.09%.

[0046] Optionally, a photosensitive unit 100 includes three photosensitive layers, wherein the difference between the indium content of any two photosensitive layers is less than or equal to 4%.

[0047] The image sensor provided in this application embodiment has an indium component content difference of less than or equal to 4% between at least two photosensitive layers, thereby appropriately expanding the range of light wavelengths that the photosensitive unit 100 can sense when sensing a color.

[0048] In one embodiment of this application, the at least two photosensitive layers include an outer photosensitive layer that is closest to the external light source. The indium content of the outer photosensitive layer is greater than the minimum indium content of the photosensitive layers other than the outer photosensitive layer among the at least two photosensitive layers, and the indium content of the outer photosensitive layer is less than the maximum indium content of the photosensitive layers other than the outer photosensitive layer among the at least two photosensitive layers.

[0049] Specifically, since the photosensitive layer corresponding to the indium content that is neither the maximum nor the minimum value has the largest range of light-sensing wavelengths, placing the photosensitive layer corresponding to the indium content that is neither the maximum nor the minimum value in the position closest to the external light source (i.e., the outer photosensitive layer) is beneficial for improving photosensitivity. For example... Figure 3As shown, in a photosensitive unit 100, the indium content of the first photosensitive layer 110 is greater than the minimum indium content of the second photosensitive layer 120 and the third photosensitive layer 130, and less than the maximum indium content of the second photosensitive layer 120 and the third photosensitive layer 130. That is, the first photosensitive layer 110 is the outer photosensitive layer, and the indium content of the first photosensitive layer 110 is the middle value of the indium content of the three photosensitive layers.

[0050] For example, such as Figure 3 As shown, taking the red photosensitive unit R100 as an example, the first photosensitive layer 110 is the outer photosensitive layer, and the first photosensitive layer 110 is located in the position closest to the external light source. Taking the green photosensitive unit G100 as an example, the first photosensitive layer 110 is the outer photosensitive layer, and the first photosensitive layer 110 is located in the position closest to the external light source. Taking the blue photosensitive unit B100 as an example, the first photosensitive layer 110 is the outer photosensitive layer, and the first photosensitive layer 110 is located in the position closest to the external light source.

[0051] In one embodiment of this application, from a process perspective, a photosensitive layer with a higher indium content is fabricated first, followed by a photosensitive layer with a lower indium content. The photosensitive layer with the highest indium content is positioned furthest from the external light source, while the photosensitive layer with the lowest indium content is positioned closest to the external light source. In short, according to the order of indium content from highest to lowest, the corresponding photosensitive layers are positioned from furthest from the external light source to closest to it.

[0052] In one embodiment of this application, firstly, from the perspective of photosensitivity efficiency, the photosensitive layer corresponding to the indium content that is neither the maximum nor the minimum value is located closest to the external light source (i.e., the outer photosensitive layer), which is beneficial to improving photosensitivity efficiency. Secondly, from a process perspective, the photosensitive layer with the highest indium content is located furthest from the external light source. Therefore, the photosensitive layer with the lowest indium content is located in the middle layer among the three photosensitive layers.

[0053] In one embodiment of this application, firstly, considering the photosensitivity efficiency, the photosensitive layer corresponding to the indium content that is neither the maximum nor the minimum value is positioned closest to the external light source (i.e., the outer photosensitive layer), which is beneficial for improving photosensitivity efficiency. Secondly, considering the light transmittance, the photosensitive layer with the lowest indium content is positioned furthest from the external light source. Therefore, the photosensitive layer with the highest indium content is positioned as the middle layer among the three photosensitive layers.

[0054] Figure 6 The diagram shown is a schematic representation of the structure of a photosensitive unit provided in another exemplary embodiment of this application. Figure 6As shown, at least two photosensitive layers sense different colors of light. The photosensitive unit 100 has three photosensitive layers that are stacked but not completely overlapped. The three photosensitive layers include a red photosensitive layer R140 that senses red light, a green photosensitive layer G150 that senses green light, and a blue photosensitive layer B160 that senses blue light. The indium content of the red photosensitive layer R140, the indium content of the green photosensitive layer G150, and the indium content of the blue photosensitive layer B160 decrease in that order.

[0055] Specifically, such as Figure 6 As shown, the photosensitive unit 100 has three photosensitive layers stacked but not completely overlapping: a red photosensitive layer R140, a green photosensitive layer G150, and a blue photosensitive layer B160. The areas of the red photosensitive layer R140, the green photosensitive layer G150, and the blue photosensitive layer B160 that do not overlap are used to set electrode lines 200; that is, the electrode lines 200 are set in the areas of each photosensitive layer that do not overlap with other photosensitive layers (non-overlapping areas W110). Furthermore, all three photosensitive layers are hexagonal in shape, with equal side lengths, and can be rotated out of alignment around a center point O.

[0056] In one embodiment of this application, the indium content of the red photosensitive layer R140, the indium content of the green photosensitive layer G150, and the indium content of the blue photosensitive layer B160 decrease in that order. For example, the indium content of the red photosensitive layer R140 is 0.50%, the indium content of the green photosensitive layer G150 is 0.25%, and the indium content of the blue photosensitive layer B160 is 0.05%. Importantly, each photosensitive unit 100 simultaneously includes the red photosensitive layer R140, the green photosensitive layer G150, and the blue photosensitive layer B160, meaning each photosensitive unit 100 can sense red, green, and blue colors, covering the entire visible light spectrum. This results in high integration and increased pixel density. When the image sensor senses ambient light, it can directly record color images across the entire visible light wavelength range in the environment.

[0057] In one embodiment of this application, a green photosensitive layer G150 is stacked on the side of the red photosensitive layer R140 away from the external light source, and / or, a blue photosensitive layer B160 is stacked on the side of the red photosensitive layer R140 away from the external light source.

[0058] Specifically, because the epitaxial crystal quality of the red photosensitive layer R140 corresponding to the high indium composition is lower during fabrication, its photosensitivity is lower than that of the green photosensitive layer G150 and also lower than that of the blue photosensitive layer B160. Therefore, the red photosensitive layer R140 is stacked on the side of the green photosensitive layer G150 closest to the external light source, and / or, the red photosensitive layer R140 is stacked on the side of the blue photosensitive layer B160 closest to the external light source, in order to improve the photosensitivity of the red photosensitive layer R140.

[0059] Optionally, such as Figure 6 As shown, the green photosensitive layer G150 is located between the red photosensitive layer R140 and the blue photosensitive layer B160. Because the blue photosensitive layer B160 has the best crystal quality and the highest photosensitive efficiency during epitaxy, it can be placed at the position furthest from the external light source.

[0060] In one embodiment of this application, at least two photosensitive layers are rotated and offset about the center of the photosensitive unit 100, so that the at least two photosensitive layers do not completely overlap.

[0061] like Figures 1 to 6 As shown, each photosensitive unit 100 comprises at least two photosensitive layers that are rotated and offset about the center point O of the photosensitive unit to obtain the following... Figures 1 to 6 The at least two photosensitive layers are shown in a partially overlapping configuration. The photosensitive unit 100 involved in the rotational offset method provided in this application embodiment has the smallest area. In an image sensor of the same area, more photosensitive units 100 can be accommodated without sacrificing photosensitive area, resulting in higher integration of the photosensitive units 100 and thus improving the dynamic range of the image sensor. Furthermore, this application embodiment does not further limit the rotational offset angle, as long as it ensures that at least two photosensitive layers do not completely overlap.

[0062] Figure 7 The diagram shown is a schematic representation of the structure of a photosensitive unit provided in another exemplary embodiment of this application. Figure 7 As shown, optionally, the three photosensitive layers contained in each photosensitive unit 100 are shifted and staggered to obtain, as shown Figure 7 The incomplete overlapping arrangement is shown. This application does not limit the translation distance of the offset layers, as long as at least two photosensitive layers do not completely overlap.

[0063] Figure 8 As shown Figure 3 Cross-sectional view along AA', as shown Figure 8 As shown, the image sensor provided in this application embodiment further includes: a charge storage component electrically connected to each photosensitive layer, wherein the charge storage component is electrically connected to the electrode line 200, and the charge storage components are electrically insulated from each other.

[0064] like Figure 8 As shown, only Figure 3The image sensor provided in this application embodiment is illustrated using a cross-sectional view along AA' of the green photosensitive unit G100 in the second row and first column as an example. The image sensor further includes: a first charge storage component 110' electrically connected to the first photosensitive layer 110, a second charge storage component 120' electrically connected to the second photosensitive layer 120, and a third charge storage component 130' electrically connected to the third photosensitive layer 130. The first charge storage component 110' stores the charge generated by the first photosensitive layer 110 sensing light. The first photosensitive layer 110 is electrically connected to the first charge storage component 110' via an electrode line 200 to transfer the charge to the first charge storage component 110'. The second charge storage component 120' stores the charge generated by the second photosensitive layer 120 sensing light. The second photosensitive layer 120 is electrically connected to the second charge storage component 120' via an electrode line 200 to transfer the charge to the second charge storage component 120'. The third charge storage component 130' is used to store the charge generated by the third photosensitive layer 130 sensing light. The third photosensitive layer 130 is electrically connected to the third charge storage component 130' through the electrode line 200 to transfer the charge to the third charge storage component 130'.

[0065] Specifically, the first charge storage component 110', the second charge storage component 120', and the third charge storage component 130' are electrically insulated from each other, meaning that each photosensitive layer is electrically connected to a separate charge storage component. The charge stored in the charge storage components is read out, converted into light signals, and used to generate high dynamic range images, giving viewers a visual experience close to that of a real environment. It should be noted that... Figure 4 The electrode line 200 in the diagram is shown as a straight line only and does not represent the actual routing path of the electrode line 200.

[0066] The image sensor provided in this application embodiment further includes: a plurality of photosensitive units 100, and an isolation member 300 disposed between two adjacent photosensitive units 100, the isolation member 300 being used to electrically insulate adjacent photosensitive units 100 from each other. Optionally, the isolation member 300 is made of insulating material. Figure 9 The diagram shown is a partially enlarged structural schematic of an isolation component provided in an exemplary embodiment of this application. Figure 9 As shown, the isolation component 300 includes a metal part 310 and an insulating layer 320 disposed on the outer surface of the metal part 310. The insulating layer 320 may be a transparent insulating material, used to electrically insulate adjacent photosensitive units 100 from each other.

[0067] In one embodiment of this application, the metal component 310 includes a metal mesh grid, which can reflect light obliquely incident on the photosensitive unit 100 back to the photosensitive unit 100 (e.g., Figure 9The incident light P and reflected light P' are shown, and light crosstalk between adjacent photosensitive units 100 is isolated. It should be noted that the insulating layer 320 is used to electrically insulate the metal mesh and the photosensitive units 100 from each other. Furthermore, the photosensitive unit 100 includes a stacked single quantum well or multiple quantum well structure.

[0068] It should be noted that this application's Figures 1 to 8 Isolation components are not shown in either of them.

[0069] The image sensor provided in this application embodiment further includes: a first semiconductor layer and a second semiconductor layer, wherein the first semiconductor layer, the photosensitive layer and the second semiconductor layer are stacked sequentially.

[0070] It should be noted that the first semiconductor layer and the second semiconductor layer are used to form a potential difference, transferring the charge generated by the first photosensitive layer 110 to the first charge storage device 110', the charge generated by the second photosensitive layer 120 to the second charge storage device 120', and the charge generated by the third photosensitive layer 130 to the third charge storage device 130'. Optionally, the first semiconductor layer includes a P-type semiconductor, and the second semiconductor layer includes an N-type semiconductor. Optionally, the first semiconductor layer includes an N-type semiconductor, and the second semiconductor layer includes a P-type semiconductor. This application does not further limit the first semiconductor layer and the second semiconductor layer, as long as they can transfer the charge generated by the photosensitive unit 100 to the charge storage device.

[0071] It should be noted that, as Figure 8 As shown, Figure 8 The first semiconductor layer or the second semiconductor layer between the first photosensitive layer 110 and the second photosensitive layer 120, or between the second photosensitive layer 120 and the third photosensitive layer 130, is omitted.

[0072] In one embodiment of this application, the photosensitive material of the photosensitive unit 100 includes indium gallium nitride (InGaN).

[0073] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0074] The terms “including,” “comprising,” “having,” etc., used in this application are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context explicitly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

Claims

1. An image sensor, characterized in that, include: At least one photosensitive unit, the photosensitive unit having at least two photosensitive layers stacked but not completely overlapping, wherein in one photosensitive unit, the area of ​​each photosensitive layer that does not overlap with other photosensitive layers is used to set electrode lines, and the at least two photosensitive layers have different photosensitive component contents.

2. The image sensor according to claim 1, characterized in that, The at least two photosensitive layers have equal areas.

3. The image sensor according to claim 1, characterized in that, The photosensitive component includes an indium-containing gallium nitride-based compound, and the photosensitive component content of the at least two photosensitive layers is different, including: the indium component content of the at least two photosensitive layers is different.

4. The image sensor according to claim 3, characterized in that, The at least two photosensitive layers sense light of the same color, and the difference between the indium content of the at least two photosensitive layers is less than or equal to 4%.

5. The image sensor according to claim 4, characterized in that, The at least two photosensitive layers include an outer photosensitive layer that is closest to the external light source. The indium content of the outer photosensitive layer is greater than the minimum indium content of the photosensitive layers other than the outer photosensitive layer, and the indium content of the outer photosensitive layer is less than the maximum indium content of the photosensitive layers other than the outer photosensitive layer.

6. The image sensor according to claim 3, characterized in that, The at least two photosensitive layers sense different colors of light. The photosensitive unit has three photosensitive layers stacked but not completely overlapping. The three photosensitive layers include a red photosensitive layer that senses red light, a green photosensitive layer that senses green light, and a blue photosensitive layer that senses blue light. The indium content of the red photosensitive layer, the indium content of the green photosensitive layer, and the indium content of the blue photosensitive layer decrease in that order.

7. The image sensor according to claim 6, characterized in that, The green photosensitive layer is stacked on the side of the red photosensitive layer away from the external light source, and / or, The blue photosensitive layer is stacked on the side of the red photosensitive layer away from the external light source.

8. The image sensor according to any one of claims 1 to 7, characterized in that, The at least two photosensitive layers are rotated and offset around the center of the photosensitive unit so that the at least two photosensitive layers do not completely overlap.

9. The image sensor according to any one of claims 1 to 7, characterized in that, Also includes: A charge storage component electrically connected to each of the photosensitive layers, wherein the charge storage component is electrically connected to the electrode line and the charge storage components are electrically insulated from each other.

10. The image sensor according to any one of claims 1 to 7, characterized in that, Also includes: A plurality of photosensitive units are disposed between two adjacent photosensitive units, the isolation component being used to electrically insulate adjacent photosensitive units from each other.

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