CN114759048A - Image sensor and electronic information device - Google Patents

Image sensor and electronic information device Download PDF

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Publication number
CN114759048A
CN114759048A CN202110023809.6A CN202110023809A CN114759048A CN 114759048 A CN114759048 A CN 114759048A CN 202110023809 A CN202110023809 A CN 202110023809A CN 114759048 A CN114759048 A CN 114759048A
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transistor
tungsten
image sensor
source
source follower
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李�杰
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Galaxycore Shanghai Ltd Corp
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Galaxycore Shanghai Ltd Corp
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14601—Structural or functional details thereof
    • H01L27/14609—Pixel-elements with integrated switching, control, storage or amplification elements
    • H01L27/14612—Pixel-elements with integrated switching, control, storage or amplification elements involving a transistor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14601—Structural or functional details thereof
    • H01L27/14636—Interconnect structures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14643—Photodiode arrays; MOS imagers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14683—Processes or apparatus peculiar to the manufacture or treatment of these devices or parts thereof
    • H01L27/14689—MOS based technologies

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Electromagnetism (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Solid State Image Pick-Up Elements (AREA)

Abstract

An image sensor and an electronic information device, the image sensor comprising: a pixel region including a plurality of pixel units; each pixel unit includes: a photodiode region, a transfer transistor, a floating diffusion region, a source follower transistor, and a reset transistor; the floating diffusion region is connected with the grid electrode of the source following transistor through a first tungsten structure, and the grid electrode of the source following transistor is connected with the source electrode of the reset transistor through a second tungsten structure. The invention can reduce the wiring parasitic capacitance of the floating diffusion region and effectively improve the performance of the image sensor on the premise of keeping the electrical connection performance.

Description

Image sensor and electronic information device
Technical Field
The present invention relates to the field of image sensors, and in particular, to an image sensor and an electronic information device.
Background
Image sensors can be classified into Complementary Metal Oxide Semiconductor (CMOS) image sensors and Charge Coupled Device (CCD) image sensors, which are generally used to convert optical signals into corresponding electrical signals. The CCD image sensor has advantages of high image sensitivity and low noise, but the integration of the CCD image sensor with other devices is difficult and the power consumption of the CCD image sensor is high. In contrast, the CMOS image sensor has the advantages of simple process, easy integration with other devices, small volume, light weight, low power consumption, low cost, and the like. At present, CMOS image sensors are widely used in still digital cameras, camera phones, digital video cameras, medical imaging devices (e.g., gastroscopes), vehicle imaging devices, and the like.
The core element of the image sensor is a Pixel unit (Pixel), and the Pixel unit directly influences factors such as the size of the image sensor, the dark current level, the noise level, the imaging transparency, the image color saturation and the image defect.
In the conventional image sensor, there is usually a pixel array (array) composed of one pixel unit, and from a layout level, a plurality of pixel units may be pieced together to form a complete pixel array, and the shape of the pixel unit may be a rectangle, a square, a polygon (triangle, pentagon, hexagon), and so on, as required.
In the conventional image sensor, the structure of the pixel unit may include various structures, such as a photoelectric conversion element plus 3 transistor structure, a photoelectric conversion element plus 4 transistor structure, or a photoelectric conversion element plus 5 transistor structure. The photoelectric conversion element plus 3 Transistor structure can be formed by directly connecting the photoelectric conversion element with a floating diffusion region, photogenerated electrons generated in the photoelectric conversion element are stored in the floating diffusion region, and the photogenerated electrons are converted and output through a Source follower Transistor (SF) under the time sequence control of a Reset Transistor (RST) and a row Select Transistor (SEL).
However, in the conventional image sensor, the provision metal layer is electrically connected to the floating diffusion region, the gate of the source follower transistor, and the source of the reset transistor, respectively, and thus a wiring parasitic capacitance is easily formed, resulting in a reduction in conversion gain.
Disclosure of Invention
The technical problem to be solved by the invention is to provide an image sensor and an electronic information device, which can avoid the formation of parasitic capacitance and effectively improve the performance of the image sensor on the premise of keeping the electrical connection performance.
To solve the above technical problem, an embodiment of the present invention provides an image sensor, including: a pixel region including a plurality of pixel units; each pixel unit includes: a photodiode region, a transfer transistor, a floating diffusion region, a source follower transistor, and a reset transistor; the floating diffusion region is connected with the grid electrode of the source following transistor through a first tungsten structure, and the grid electrode of the source following transistor is connected with the source electrode of the reset transistor through a second tungsten structure.
Optionally, a first trench isolation structure is present between a region of the floating diffusion region in contact with the first tungsten structure and a channel of the source follower transistor.
Optionally, a second trench isolation structure is present between a region of the second tungsten structure in contact with the source of the reset transistor and the channel of the source follower transistor.
Optionally, no metal layer is disposed above the first tungsten structure and the second tungsten structure and electrically connected thereto.
Optionally, the forming process of the first tungsten structure and the second tungsten structure at least includes the following steps: forming gate structures of the transmission transistor, the source follower transistor and the reset transistor; forming side walls of the transmission transistor, the source following transistor and the reset transistor; forming the floating diffusion region, the source and drain of the source follower transistor, and the source and drain of the reset transistor; laying a dielectric layer to cover the gate structures of the transmission transistor, the source follower transistor and the reset transistor; etching the dielectric layer to form a first groove structure and a second groove structure, wherein the ratio of the etching rate of the dielectric layer to the etching rate of the side wall of the source follower transistor is greater than a certain critical value; laying tungsten to cover the first trench structure and the second trench structure.
Optionally, the forming process of the first tungsten structure and the second tungsten structure further includes: before the dielectric layer is etched, flattening the dielectric layer through a chemical mechanical polishing process; and/or flattening the formed first tungsten structure and the second tungsten structure through a chemical mechanical polishing process after the tungsten is paved.
Optionally, the image sensor further includes: a metal interconnection layer; a color filter; a microlens.
Optionally, the first tungsten structure and the second tungsten structure are separate structures.
Optionally, the first tungsten structure and the second tungsten structure are of a monolithic structure.
In order to solve the above technical problem, an embodiment of the present invention provides an electronic information device, including the above image sensor.
Compared with the prior art, the technical scheme of the embodiment of the invention has the following beneficial effects:
in the embodiment of the invention, the floating diffusion region is connected with the gate of the source follower transistor through the first tungsten structure, and the gate of the source follower transistor is connected with the source of the reset transistor through the second tungsten structure.
Drawings
FIG. 1 is a circuit diagram of a pixel cell of an image sensor in the prior art;
FIG. 2 is a schematic cross-sectional view of an image sensor of the prior art;
FIG. 3 is a top view of an image sensor in an embodiment of the present application;
FIG. 4 is a cross-sectional view taken along line A1-A2 of FIG. 3;
FIG. 5 is a flow chart of a method of forming an image sensor in an embodiment of the present application;
fig. 6 is a schematic cross-sectional structure diagram of another image sensor in the embodiment of the present application.
Detailed Description
As described above, in the conventional image sensor, taking the photoelectric conversion element plus 3 transistor structure as an example, the photoelectric conversion element may be directly connected to the floating diffusion region, the photo-generated electrons generated in the photoelectric conversion element are stored in the floating diffusion region, and the photo-generated electrons are converted and output through the source follower transistor under the timing control of the reset transistor and the row select transistor. However, in the conventional image sensor, the provision metal layer is electrically connected to the floating diffusion region, the gate of the source follower transistor, and the source of the reset transistor, respectively, and thus parasitic capacitance is easily formed, resulting in a reduction in conversion gain.
Referring to fig. 1 in particular, fig. 1 is a schematic circuit diagram of a pixel unit of an image sensor in the prior art.
Specifically, a basic photosensitive unit of a CMOS Image Sensor (CIS) is called a pixel, and the pixel unit includes one photodiode and 3 or 4 MOS transistors, called a 3T type or a 4T type, and most CIS is currently the 4T type.
The 4T-type CIS shown in fig. 1 may include: 4 MOS transistors, which are respectively a reset transistor RST, a source follower transistor SF, a row select transistor SEL, and a transfer transistor Tx, and a Photodiode (PD).
The operating principle of the pixel unit of the 4T type CIS shown in fig. 1 will be explained below. Specifically, before receiving illumination, the reset transistor RST and the transfer transistor Tx are turned on, and the other transistors are turned off to reset the floating diffusion FD and the photodiode PD; then, all transistors are turned off, the photodiode PD receives light, and performs photoelectric conversion to form a photogenerated carrier; then the transfer transistor Tx is turned on, the other transistors are turned off, and the photogenerated carriers are transferred from the photodiode PD to the floating diffusion FD; then, the source follower transistor SF and the row select transistor SEL are turned on, and photo-generated carriers are sequentially output from the floating diffusion region FD through the source follower transistor SF and the row select transistor SEL, thereby completing the collection and transmission of primary optical signals.
Referring to fig. 2, fig. 2 is a schematic cross-sectional view of an image sensor in the prior art.
In the image sensor shown in fig. 2, a semiconductor substrate 100 is included, and a pixel region including a plurality of pixel units is formed inside and on a surface of the semiconductor substrate 100.
Wherein each pixel unit may include: a photodiode region 110, a transfer transistor 130, a floating diffusion region 131, a source follower transistor 140, and a reset transistor 150.
Further, in order to realize the connection between the floating diffusion region 131 and the source follower transistor 140, and the connection between the source follower transistor 140 and the reset transistor 150, the set metal layer 160 is electrically connected to the floating diffusion region 130, the source follower transistor 140, and the reset transistor 150, respectively.
The metal layer 160 may be a metal layer of a metal interconnection layer of the image sensor, such as a first metal layer (M1).
The inventors of the present invention have studied and found that, in the prior art, the metal layer 160 is required to be relied upon to achieve the connection between the floating diffusion region 131 and the source follower transistor 140 and the connection between the source follower transistor 140 and the reset transistor 150, but due to the connection through the metal layer 160, parasitic capacitance is also brought along, which results in the reduction of the conversion gain of the floating diffusion region 131.
In the embodiment of the invention, the floating diffusion region is connected with the gate of the source follower transistor through the first tungsten structure, and the gate of the source follower transistor is connected with the source of the reset transistor through the second tungsten structure.
In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, embodiments accompanying figures are described in detail below.
Referring to fig. 3 and 4 in combination, fig. 3 is a top view of an image sensor in an embodiment of the present application, and fig. 4 is a cross-sectional view taken along cutting line a1-a2 in fig. 3.
In the image sensor shown in fig. 3, a semiconductor substrate 200 may be included, and a pixel region may be formed inside and on a surface of the semiconductor substrate 100, and the pixel region may include a plurality of pixel units.
Wherein each pixel unit may include: a photodiode region 210, a transfer transistor 230, a floating diffusion region 231, a source follower transistor 240, and a reset transistor 250.
Wherein the floating diffusion region 231 is connected to the gate of the source follower transistor 240 through a first tungsten structure 261, and the gate of the source follower transistor 240 is connected to the source of the reset transistor 250 through a second tungsten structure 262.
In a specific implementation, the semiconductor substrate 200 may be a silicon substrate, or the material of the semiconductor substrate 200 may further include germanium, silicon carbide, gallium arsenide, or indium gallium arsenide, and the semiconductor substrate 200 may also be a silicon substrate on an insulator or a germanium substrate on an insulator, or a substrate on which an epitaxial layer (Epi layer) is grown.
The photodiode 210 is capable of generating photo-generated carriers, such as electrons, when excited by external light. The photodiode 210 can be formed by an ion implantation process, and by controlling the energy and concentration of the ion implantation, the depth and implantation range of the ion implantation can be controlled, thereby controlling the depth and thickness of the photodiode 210.
Further, each pixel unit may further include: a select transistor (not shown) that may be connected to the source follower transistor 240.
For the operation principle of the transfer transistor 230, the floating diffusion 231, the source follower transistor 240, and the reset transistor 250 and further description, reference may be made to the foregoing and fig. 1, and further description is omitted here.
The first tungsten structure 261 and the second tungsten structure 262 may be formed by using metal tungsten, for example, by using a physical sputtering process or a chemical vapor deposition process.
In the embodiment of the present invention, by providing the floating diffusion region 231 to be connected to the gate of the source follower transistor 240 through the first tungsten structure 261, compared with the prior art in which a metal layer is arranged to be electrically connected with the floating diffusion region, the gate of the source follower transistor and the source of the reset transistor respectively, which results in formation of parasitic capacitance and reduction of conversion gain, the gate of the source follower transistor 240 is connected with the source of the reset transistor 250 through the second tungsten structure 262, and the scheme of the embodiment of the present invention is adopted, electrical connections between the floating diffusion region 231 and the gate of the source follower transistor 240 and between the gate of the source follower transistor 240 and the source of the reset transistor 250 can still be made without relying on a metal layer, therefore, on the premise of keeping the electrical connection performance, the formation of parasitic capacitance is avoided, and the performance of the image sensor is effectively improved.
Further, a first trench isolation structure 221 may exist between a region of the floating diffusion region 231 in contact with the first tungsten structure 261 and a channel of the source follower transistor 240.
Further, a second trench isolation structure 222 may be present between a region of the second tungsten structure 262 in contact with the source of the reset transistor 250 and the channel of the source follower transistor 240.
The first trench isolation structure 221 and the second trench isolation structure 222 may be formed of an insulating material, such as silicon oxide (SiO)2) A material.
It is noted that the first Trench Isolation structure 221 and the second Trench Isolation structure 222 have smaller depths and can be regarded as Shallow Trench Isolation (STI) than Deep Trench Isolation (DTI) which is also formed in a subsequent process of the conventional image sensor. Wherein the depth direction is perpendicular to the surface of the semiconductor substrate 200.
Referring to fig. 5, fig. 5 is a partial flowchart of a method for forming an image sensor in an embodiment of the present application.
Specifically, the forming process of the first tungsten structure and the second tungsten structure may include at least step S51 to step S56:
Step S51: forming gate structures of the transmission transistor, the source follower transistor and the reset transistor;
step S52: forming side walls of the transmission transistor, the source following transistor and the reset transistor;
step S53: forming the floating diffusion region, the source and drain of the source follower transistor, and the source and drain of the reset transistor;
step S54: laying a dielectric layer to cover the gate structures of the transmission transistor, the source follower transistor and the reset transistor;
step S55: etching the dielectric layer to form a first groove structure and a second groove structure, wherein the ratio of the etching rate of the dielectric layer to the etching rate of the side wall of the source follower transistor is greater than a certain critical value;
step S56: laying tungsten to cover the first trench structure and the second trench structure.
The above steps will be described with reference to fig. 3 and 4.
Firstly, forming gate structures of the transmission transistor 230, the source follower transistor 240 and the reset transistor 250, then forming side walls of the transmission transistor 230, the source follower transistor 240 and the reset transistor 250, and then forming the floating diffusion region 231, the source and drain 241 of the source follower transistor 240 and the source and drain 251 of the reset transistor 250.
Wherein, Gate structure (Gate) and side wall (Spacer) can select appropriate process parameter to form according to the technology platform of specifically adopting, and this application embodiment does not give unnecessary details to this.
Note that since the source follower transistor 240 is perpendicular to the channel direction of the reset transistor 250, the direction of a line connecting the source and the drain 241 of the source follower transistor 240 and the direction of a line connecting the source and the drain 251 of the reset transistor 250 are also perpendicular, and the source and the drain 241 of the source follower transistor 240 cannot be shown in fig. 4.
A dielectric layer (not shown) is then laid down, which may cover the gate structures of the transfer transistor 230, the source follower transistor 240, and the reset transistor 250.
And then, etching the dielectric layer to form a first trench structure (not shown) and a second trench structure (not shown), wherein a ratio of a rate of etching the dielectric layer to a rate of etching the sidewall of the source follower transistor 240 is greater than a certain critical value.
Further, before etching the dielectric layer, the forming process of the first tungsten structure 261 and the second tungsten structure 262 may further include: and flattening the dielectric layer by a chemical mechanical polishing process.
In the embodiment of the invention, the dielectric layer is flattened by adopting a chemical mechanical polishing process, so that the consistency of the surface topography of the image sensor can be effectively improved, and the improvement of the device performance is facilitated.
In specific implementation, the dielectric layer may be formed by using a suitable material, for example, a silicon oxide or a silicon nitride material, and the sidewall of the source follower transistor 240 may also be formed by using a suitable material, for example, a silicon carbide nitride (SiCN), a silicon oxide, or a silicon nitride material. It should be noted that the dielectric layer may be a single material, such as one of the three materials, or may be a material formed by stacking multiple materials, such as a stack of silicon oxide and silicon nitride, to relieve stress on the wafer.
The etching ratio of the dielectric layer to the sidewall of the source follower transistor 240 may be greater than a preset threshold.
In the embodiment of the present invention, by setting the etching ratio of the dielectric layer to the side wall of the source follower transistor 240 to be greater than the preset threshold, the side wall of the source follower transistor 240 can be effectively protected when the dielectric layer adjacent to the side wall is etched after the side wall is formed.
Tungsten is then laid to cover the first and second trench structures, thereby forming the first and second tungsten structures 261 and 262.
Further, before etching the dielectric layer, the forming process of the first tungsten structure 261 and the second tungsten structure 262 may further include: after the laying of the tungsten, the formed first tungsten structure 261 and the second tungsten structure 262 are planarized by a chemical mechanical polishing process.
In the embodiment of the invention, the first tungsten structure 261 and the second tungsten structure 262 are planarized by using a chemical mechanical polishing process, so that the consistency of the surface topography of the image sensor can be effectively improved, and the improvement of the device performance is facilitated.
Further, there is no metal layer above the first tungsten structure 261 and the second tungsten structure 262 to electrically connect therewith.
In the embodiment of the present invention, by disposing the first tungsten structure 261 and the second tungsten structure 262 without a metal layer above them and electrically connecting them, the electrical connection between the floating diffusion region 231 and the gate of the source follower transistor 240 and between the gate of the source follower transistor 240 and the source of the reset transistor 250 can still be achieved without depending on the metal layer.
Further, in the first specific implementation manner of the embodiment of the present invention, the first tungsten structure 261 and the second tungsten structure 262 may be separate structures.
It is noted that the first tungsten structure 261 and the second tungsten structure 262 may be electrically connected to each other through a gate of the source follower transistor 240.
Furthermore, the gate of the source follower transistor 240 may be made of polysilicon (Poly) material, and may also be made of High-K metal gate (High-K gate) material to meet the requirements of various semiconductor devices and to have conductivity.
Further, in the second specific implementation of the embodiment of the present invention, the first tungsten structure 261 and the second tungsten structure 262 may be a unitary structure.
Referring to fig. 6, fig. 6 is a schematic cross-sectional structure diagram of another image sensor in the embodiment of the present application.
The other image sensor may include a plurality of structures in the image sensor shown in fig. 4, and may further include a tungsten structure 360, and charge transfer may be directly performed inside the tungsten structure 360. It is understood that the tungsten structure 360 may be regarded as the first tungsten structure 261 and the second tungsten structure 262 in fig. 4, that is, the first tungsten structure 261 and the second tungsten structure 262 may be a unitary structure.
In the embodiment of the present invention, by providing the first tungsten structure 261 and the second tungsten structure 262 as separate structures or as an integral structure, it is possible to improve flexibility of the arrangement on the basis of realizing electrical connection between the first tungsten structure 261 and the second tungsten structure 262, so as to achieve balance between production cost and conduction efficiency.
Further, the image sensor may further include: metal interconnect layers (not shown); color filters (not shown); microlenses (not shown).
The metal interconnection layer is used for realizing conduction among the multiple metal layers, the color filter is used for realizing absorption, reflection and penetration of light, and the micro lens is used for refracting incident light so as to achieve the effect of absorbing more light.
Specifically, the metal interconnection layer, the color filter, and the microlens may be formed by using appropriate process parameters, which are not limited in the embodiments of the present application.
In the embodiment of the application, an electronic information device is further disclosed, and the electronic information device comprises the image sensor.
It should be noted that the electronic information device includes, but is not limited to, a mobile phone, a computer, a tablet computer, and other terminal devices.
Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (10)

1. An image sensor, comprising:
a pixel region including a plurality of pixel units;
each pixel unit includes: a photodiode region, a transfer transistor, a floating diffusion region, a source follower transistor, and a reset transistor;
the floating diffusion region is connected with the grid electrode of the source following transistor through a first tungsten structure, and the grid electrode of the source following transistor is connected with the source electrode of the reset transistor through a second tungsten structure.
2. The image sensor of claim 1, wherein a first trench isolation structure is present between a region of the floating diffusion region in contact with the first tungsten structure and a channel of the source follower transistor.
3. The image sensor of claim 1, wherein a second trench isolation structure is present between a region of the second tungsten structure in contact with the source of the reset transistor and the channel of the source follower transistor.
4. The image sensor of claim 1, wherein no metal layer is electrically connected to the first tungsten structure and the second tungsten structure over the first tungsten structure and the second tungsten structure.
5. The image sensor of claim 1, wherein the forming of the first and second tungsten structures comprises at least the steps of:
forming gate structures of the transmission transistor, the source follower transistor and the reset transistor;
forming side walls of the transmission transistor, the source following transistor and the reset transistor;
forming the floating diffusion region, the source and drain of the source follower transistor, and the source and drain of the reset transistor;
laying a dielectric layer to cover the gate structures of the transmission transistor, the source follower transistor and the reset transistor;
etching the dielectric layer to form a first groove structure and a second groove structure, wherein the ratio of the etching speed of the dielectric layer to the etching speed of the side wall of the source follower transistor is larger than a certain critical value;
laying tungsten to cover the first trench structure and the second trench structure.
6. The image sensor of claim 5, wherein the forming of the first and second tungsten structures further comprises:
Before the dielectric layer is etched, flattening the dielectric layer through a chemical mechanical polishing process;
and/or flattening the formed first tungsten structure and the second tungsten structure through a chemical mechanical polishing process after the tungsten is paved.
7. The image sensor of claim 5, wherein the image sensor further comprises: a metal interconnection layer; a color filter; a microlens.
8. The image sensor of claim 1, wherein the first tungsten structure and the second tungsten structure are separate structures.
9. The image sensor of claim 1, wherein the first tungsten structure and the second tungsten structure are monolithic structures.
10. An electronic information device characterized by comprising the image sensor according to any one of claims 1 to 9.
CN202110023809.6A 2021-01-08 2021-01-08 Image sensor and electronic information device Pending CN114759048A (en)

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Application Number Priority Date Filing Date Title
CN202110023809.6A CN114759048A (en) 2021-01-08 2021-01-08 Image sensor and electronic information device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110023809.6A CN114759048A (en) 2021-01-08 2021-01-08 Image sensor and electronic information device

Publications (1)

Publication Number Publication Date
CN114759048A true CN114759048A (en) 2022-07-15

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Family Applications (1)

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CN202110023809.6A Pending CN114759048A (en) 2021-01-08 2021-01-08 Image sensor and electronic information device

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