CN108807447B - Image sensor and forming method thereof - Google Patents
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- CN108807447B CN108807447B CN201810877186.7A CN201810877186A CN108807447B CN 108807447 B CN108807447 B CN 108807447B CN 201810877186 A CN201810877186 A CN 201810877186A CN 108807447 B CN108807447 B CN 108807447B
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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
- H01L27/14643—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
Abstract
The technical scheme of the invention discloses an image sensor and a forming method thereof, wherein the forming method of the image sensor comprises the following steps: providing a semiconductor substrate in which discrete photodiodes are formed; forming a first insulating layer on the surface of the semiconductor substrate; forming discrete metal plugs on the surface of the first insulating layer; forming an interlayer dielectric layer on the surface of the first insulating layer, wherein the interlayer dielectric layer also covers the side wall of the metal bolt; forming a second insulating layer on the surface of the interlayer dielectric layer; and etching the second insulating layer to form a reflecting region corresponding to the photodiode, wherein the surface of the reflecting region far away from the photodiode is a convex surface. The technical scheme of the invention effectively reduces the optical crosstalk.
Description
Technical Field
The present invention relates to the field of semiconductor device manufacturing, and more particularly, to an image sensor and a method of forming the same, and more particularly, to a backside illuminated image sensor and a method of forming the same.
Background
The image sensor receives an optical signal from an object and converts the optical signal into an electrical signal, which may then be transmitted for further processing, such as digitization, and then storage in a storage device, such as a memory, optical or magnetic disk, or for display on a display, printing, or the like. Image sensors are commonly used in devices such as digital cameras, video cameras, scanners, facsimile machines, and the like.
Image sensors are generally of two types, a Charge Coupled Device (CCD) sensor and a CMOS Image Sensor (CIS). The CCD is called a photo-coupler, and charges are collected by a photoelectric effect, and the charges of pixels of each row are sent to an analog shift register along with a clock signal and then serially converted into a voltage. The CIS is a rapidly developed solid-state image sensor, and since an image sensor portion and a control circuit portion in the CMOS image sensor are integrated in the same chip, the CMOS image sensor has a small volume, low power consumption, and a low price, and is superior to a conventional CCD (charge coupled) image sensor and more easily popularized.
The conventional CMOS image sensor mainly includes a Front-side Illumination (FSI) CMOS image sensor and a Back-side Illumination (BSI) CMOS image sensor. Wherein, in the back-illuminated image sensor, light is incident on a photodiode in the image sensor from the back surface of the image sensor, thereby converting light energy into electric energy; the back-illuminated CMOS image sensor is more widely used due to its better photoelectric conversion effect (i.e., high quantum conversion efficiency).
In the prior art, a groove is etched in a dielectric layer and a reflective substance is filled in the groove, so that the quantum conversion efficiency of long-wavelength light is improved through reflection. However, the crosstalk problem of light of the image sensor remains to be solved.
Disclosure of Invention
The technical problem to be solved by the technical scheme of the invention is to reduce the crosstalk of light in the image sensor.
In order to solve the above technical problem, an embodiment of the present invention provides a method for forming an image sensor, including: providing a semiconductor substrate in which discrete photodiodes are formed; forming a first insulating layer on the surface of the semiconductor substrate; forming discrete metal plugs on the surface of the first insulating layer; forming an interlayer dielectric layer on the surface of the first insulating layer, wherein the interlayer dielectric layer also covers the side wall of the metal bolt; forming a second insulating layer on the surface of the interlayer dielectric layer; and etching the second insulating layer to form a reflecting region corresponding to the photodiode, wherein the surface of the reflecting region far away from the photodiode is a convex surface.
Optionally, the convex surface of the reflecting region has a radius of curvature of
The optional method for etching the surface of the reflection area to form the convex surface is a dry etching method, and the adopted gas comprises CF series gas.
Optionally, at the same time as, before, or after the forming of the reflective region, the method further includes: and etching the second insulating layer to expose the metal bolt to form a metal wiring area.
Optionally, the method further includes: forming a metal layer on the second insulating layer, and covering the metal layer on the reflection region and the metal wiring region; and flattening the metal layer by adopting a chemical mechanical polishing process until the second insulating layer is exposed, forming metal wiring on the metal bolt, and forming a metal reflecting layer on the reflecting area, wherein the contact surface of the metal reflecting layer and the reflecting area is a concave surface.
Optionally, the metal layer material is copper or aluminum or tungsten.
Optionally, after the forming of the second insulating layer, the method further includes: forming a hard mask layer on the second insulating layer; etching the hard mask layer and defining a reflection area pattern; forming a photoresist layer on the surface of the reflection region pattern; annealing to form a convex surface on the surface of the photoresist layer; and etching the second insulating layer along the photoresist layer by taking the hard mask layer as a mask.
Optionally, the annealing temperature is 180-240 ℃, and the annealing time is 50-80 seconds.
The present invention also provides an image sensor comprising: a semiconductor substrate; the photodiode is positioned in the semiconductor substrate, and the two photoelectric electrode tubes are arranged separately; the first insulating layer is positioned on the surface of the semiconductor substrate; the metal plug is positioned on the surface of the first insulating layer; the interlayer dielectric layer is positioned on the surface of the first insulating layer and covers the side wall of the metal bolt; the second insulating layer is positioned on the surface of the interlayer dielectric layer; and the reflecting region is positioned in the second insulating layer above the photodiode, and the surface of the reflecting region, which is far away from the photodiode, is a convex surface.
Optionally, the method further includes: the metal reflecting layer is positioned on the reflecting area, the surface of the metal reflecting layer is flush with the surface of the second insulating layer, and the contact surface of the metal reflecting layer and the reflecting area is a concave surface; and the metal wiring is positioned in the second insulating layer and is electrically connected with the metal bolt.
Compared with the prior art, the technical scheme of the invention has the following beneficial effects:
the surface of the reflecting area is made into a convex surface, so that the reflecting surface of the metal reflecting layer which is subsequently contacted with the reflecting area is a concave surface, and the metal reflecting layer can have the function of a concave mirror. When light that has passed through the photodiode but has not been absorbed is reflected by the metal reflective layer, the light is reflected at different angles, that is, the reflected light is deflected inward toward the incident side, because the normal direction of each point of the surface of the metal reflective layer is different. Therefore, even light reflected at the edge of the metal reflective layer does not enter the adjacent photodiode but is reflected back into the photodiode located below the metal reflective layer. On the premise of improving the light absorption efficiency, the crosstalk of light is effectively reduced.
Drawings
Fig. 1 is a schematic structural diagram of a conventional back-illuminated image sensor.
Fig. 2 to 6 are schematic structural diagrams corresponding to steps of a method for forming a backside illuminated image sensor according to a first embodiment of the present invention;
fig. 7 to 14 are schematic structural diagrams corresponding to steps of a method for forming a back-illuminated image sensor according to a second embodiment of the present invention.
Detailed Description
In the prior art, a groove is etched in a dielectric layer and a reflective substance is filled in the groove, so that the quantum conversion efficiency of long-wavelength light is improved through reflection.
Specifically, reference may be made to a back-illuminated image sensor shown in fig. 1.
Fig. 1 is a schematic structural diagram of a conventional back-illuminated image sensor.
Referring to fig. 1, the image sensor includes: a semiconductor substrate 10; the photodiodes 11 are positioned in the semiconductor substrate 10 and are arranged separately; a first insulating layer 12 located on the surface of the semiconductor substrate 10 and covering the photodiode 11; metal plugs 13 separately arranged on the surface of the first insulating layer 12; an interlayer dielectric layer 14, which is located on the surface of the first insulating layer 12 and covers the sidewall of the metal plug 13; the second insulating layer 15 is positioned on the surface of the interlayer dielectric layer 14; a metal reflective layer 16a located within the second insulating layer 15 and above the photodiode 15; the metal wiring 16b is electrically connected to the metal plug 13.
The inventors of the present invention have studied and found that in the back-illuminated image sensor having the above-described structure, since the reflection surface of the reflection layer 16a is a flat surface, light may directly enter the adjacent photodiode 11 at the edge of the reflection surface to cause crosstalk.
In order to solve the above technical problems, the inventors have found through creative research that a metal reflective layer is disposed at a position corresponding to a photodiode, and a reflective surface of the metal reflective layer is made to be a convex surface, so that light that passes through the photodiode but is not absorbed is reflected back to the corresponding photodiode through the concave reflective surface of the metal reflective layer, thereby effectively reducing crosstalk of light.
The technical solution of the present invention will be described in detail below with reference to the embodiments and the accompanying drawings.
First embodiment
Fig. 2 to 6 are schematic structural diagrams corresponding to steps of a method for forming a backside illuminated image sensor according to a first embodiment of the present invention.
Referring to fig. 2, a semiconductor substrate 100 is provided, and a photodiode 110 is formed within the semiconductor substrate 100; forming a first insulating layer 120 on the front surface of the semiconductor substrate 100; forming a discrete metal plug 130 on the surface of the first insulating layer 120; forming an interlayer dielectric layer 140 on the surface of the first insulating layer 120, wherein the interlayer dielectric layer 140 covers the sidewall of the metal plug 130; and forming a second insulating layer 150 on the surface of the interlayer dielectric layer 140.
In this embodiment, the semiconductor substrate 100 may be a silicon substrate, or the material of the semiconductor substrate 100 may also be germanium, silicon carbide, gallium arsenide, or indium gallium arsenide, and the semiconductor substrate 100 may also be a silicon substrate on an insulator, a germanium substrate on an insulator, or a substrate on which an epitaxial layer is grown.
In this embodiment, the photodiode 110 is a light sensing device, and converts a received optical signal into an electrical signal. In order to meet the requirement of thinning the total thickness of the semiconductor substrate 100, the positions of the photodiodes 110 in the semiconductor substrate 100 are generally at substantially the same depth.
In this embodiment, the first insulating layer 120 may be silicon oxide, the interlayer dielectric layer 140 may be silicon oxide or silicon nitride, and the second insulating layer 150 may be silicon oxide.
Referring to fig. 3, a first photoresist layer 181 is formed on the surface of the second insulating layer 150; patterning the first photoresist layer 181 to define a reflection region pattern and a metal wiring region pattern; and etching the second insulating layer 150 along the reflection region pattern and the metal wiring region pattern by using the patterned first photoresist layer 181 as a mask until the interlayer dielectric layer 140 is exposed, thereby forming a reflection region 150a and a metal wiring region 150b, wherein the reflection region 150a corresponds to each photodiode 110, and the metal wiring region 150b exposes the surface of the metal plug 130.
In this embodiment, the process of forming the first photoresist layer 181 may be a spin coating process.
In this embodiment, the method for forming the reflective region 150a and the metal wiring region 150b by etching may be a dry etching process, and the adopted gas includes CF series gas, such as CF4。
In addition to defining and etching the reflective region 150a and the metal wiring region 150b simultaneously in this embodiment, the reflective region 150a may be defined and etched first, and then the metal wiring region 150b may be defined and etched; the metal wiring region 150b may be defined and etched first, and then the reflective region 150a may be defined and etched.
Referring to fig. 4, the first photoresist layer 181 shown in fig. 3 is removed, a second photoresist layer 182 is formed on the surface of the second insulating layer 150, and the second photoresist layer 182 is patterned to expose the reflective region 150 a; and etching the reflection region 150a by using the patterned second photoresist layer 182 as a mask, so that the surface of the reflection region 150a away from the photodiode is a convex surface.
In this embodiment, the convex surface of the reflective region 150a has a radius of curvature of
Can be that
Or
And the like. If the radius of curvature is greater than
In the wordThe effect of light condensation cannot be achieved, if the curvature radius is smaller than
In other words, light cannot be collected at the position of the photodiode.
In this embodiment, the process of removing the first photoresist layer 181 may be an ashing method, and the process of forming the second photoresist layer 182 may be a spin coating method.
In this embodiment, the method for etching the reflective region 150a to form the convex surface may be a dry etching process, and the gas of the dry etching process includes CF series gas, such as CF4. The curvature radius of the convex surface is controlled by adjusting the gas concentration dose in the etching process.
Referring to fig. 5, the second photoresist layer 182 shown in fig. 4 is removed; a metal layer 160 is formed on the surface of the second insulating layer 150, and the metal layer 160 covers the reflective region and the metal wiring region.
In this embodiment, the material of the metal layer 160 may be copper, aluminum, tungsten, or the like, and the process of forming the metal layer 160 is an electroplating method.
In this embodiment, the process of removing the second photoresist layer 182 is an ashing method.
Referring to fig. 6, the metal layer 160 is planarized by a chemical mechanical polishing process until the surface of the second insulating layer 150 is exposed, a metal reflective layer 160a is formed on the reflective region, and a metal wire 160b is formed on the metal wire region.
In this embodiment, since the convex surface of the reflective region is connected to the lower surface of the metal reflective layer 160a, the lower surface of the metal reflective layer 160a is concave, and the curvature radius is also the same
Can be that
Or
And the like.
In the present embodiment, fig. 2 to 6 are longitudinal sectional views, and the planar distribution of the metal reflective layer 160a cannot be shown in the above-described drawings. However, the metal reflective layers 160a are respectively located above the photodiodes 110 distributed in the array, and have no edges connected to each other. That is, the metal reflective layers 160a are distributed in a lattice shape on the surface of the second insulating layer 150.
The image sensor formed by the above embodiment includes: a semiconductor substrate 100; a photodiode 110; are located in the semiconductor substrate 100 and are formed separately; a first insulating layer 120 located on the surface of the semiconductor substrate 100; metal plugs 130 separately arranged on the surface of the first insulating layer 120; an interlayer dielectric layer 140 on the surface of the first insulating layer 120 and covering the sidewalls of the metal plugs 130; a second insulating layer 150 on the surface of the interlayer dielectric layer 140; a reflective region 150a located in the second insulating layer 150 above the photodiode 110, wherein a surface of the reflective region 150a away from the photodiode 110 is a convex surface; a metal wiring region 150b in the second insulating layer 150 above the metal plug 130; a metal reflective layer 160a located on the reflective region 150a, wherein an upper surface of the metal reflective layer is flush with a surface of the second insulating layer 150, a lower surface of the metal reflective layer 160a is connected to a convex surface of the reflective region 150a, and a lower surface of the metal reflective layer 160a is a concave surface; and a metal wire 160b located in the metal wire region 150b and electrically connected to the metal plug 130.
Second embodiment
Fig. 7 to 14 are schematic structural diagrams corresponding to steps of a method for forming a backside illuminated image sensor according to a second embodiment of the present invention.
Referring to fig. 7, a semiconductor substrate 200 is provided, and a photodiode 210 is formed in the semiconductor substrate 200; forming a first insulating layer 220 on the semiconductor substrate 200; forming a discrete metal plug 230 on the surface of the first insulating layer 220; forming an interlayer dielectric layer 240 on the surface of the first insulating layer 220, wherein the interlayer dielectric layer 240 covers the sidewalls of the metal plugs 230; and forming a second insulating layer 250 on the surface of the interlayer dielectric layer 240.
In this embodiment, the semiconductor substrate 200 may be a silicon substrate, or the material of the semiconductor substrate 200 may also be germanium, silicon carbide, gallium arsenide, or indium gallium arsenide, and the semiconductor substrate 200 may also be a silicon substrate on an insulator, a germanium substrate on an insulator, or a substrate on which an epitaxial layer is grown.
In this embodiment, the photodiode 210 is a photosensitive device, and converts a received optical signal into an electrical signal. In order to meet the requirement of thinning the total thickness of the semiconductor substrate 200, the positions of the photodiodes 210 in the semiconductor substrate 200 are generally at substantially the same depth.
In this embodiment, the first insulating layer 220 may be silicon oxide, the interlayer dielectric layer 240 may be silicon oxide or silicon nitride, and the second insulating layer 250 may be silicon oxide.
Referring to fig. 8, a hard mask layer 290 is formed on the surface of the second insulating layer 250; next, a third photoresist layer 283 is formed on the hard mask layer 290. Patterning the third photoresist layer 283; and etching the hard mask layer 290 to expose the second insulating layer 250 by using the patterned third photoresist layer 283 as a mask, thereby defining a reflection region pattern 250 a.
In this embodiment, the process of forming the third photoresist layer 283 may be a spin coating process.
In this embodiment, the process of forming the hard mask layer 290 may be a chemical vapor deposition method, and the hard mask layer 290 may be made of silicon nitride, silicon oxynitride, or the like.
In this embodiment, the process of etching the hard mask layer 190 may be a dry etching process.
Referring to fig. 9, the third photoresist layer 283 patterned in fig. 8 is removed; forming a fourth photoresist layer 284 on the surface of the hard mask layer 290; the fourth photoresist layer 284 is patterned, and only the fourth photoresist layer 284 positioned in the reflective region pattern 250a remains.
In this embodiment, the process of removing the third photoresist layer 283 may be an ashing method. The process of forming the fourth photoresist layer 284 may be a spin coating process.
Referring to fig. 10, an annealing process is performed to form a convex surface on the upper surface of the fourth photoresist layer 284.
In this embodiment, the annealing temperature of the fourth photoresist layer is 180 ℃ to 240 ℃ and the annealing time is 50 seconds to 80 seconds; when the annealing temperature is low, the corresponding annealing time is long, and when the annealing temperature is high, the annealing time is correspondingly short. In this example, an annealing temperature of about 200 ℃ and an annealing time of about 60 seconds was used.
Referring to fig. 11, the hard mask layer 290 is used as a mask, the second insulating layer 250 is etched along the pattern defined by the fourth photoresist layer 284, so as to form a reflective region 250a ', and a convex surface is formed on the surface of the reflective region 250 a'; the hard mask layer 290 is removed.
In this embodiment, the convex surface of the reflective region 250 a' has a radius of curvature of
Can be that
Or
And the like.
Referring to fig. 12, a fifth photoresist layer 285 is formed on the second insulating layer 250; patterning the fifth photoresist layer 285 to define a metal wiring area pattern above the metal plug 230; and etching the second insulating layer 250 along the metal wiring region pattern by using the patterned fifth photoresist layer 285 as a mask to expose the surface of the metal plug 230, thereby forming a metal wiring region 250 b.
Referring to fig. 13, the fifth photoresist layer 285 shown in fig. 12 is removed; a metal layer 260 is formed on the second insulating layer 250, and the metal layer 260 covers the metal wiring region 250b and the reflective region 250 a'.
In this embodiment, the metal layer 260 is made of copper, aluminum, tungsten, or the like. The process of forming the metal layer 260 is an electroplating method.
Referring to fig. 14, the metal layer is planarized by a chemical mechanical polishing process until the surface of the second insulating layer 250 is exposed, a metal reflective layer 260a is formed on the reflective region, and a metal wire 260b is formed on the metal wire region.
In this embodiment, since the convex surface of the reflective region 250 a' is connected to the lower surface of the metal reflective layer 260a, the radius of curvature of the lower surface of the metal reflective layer 260a is also equal to
In the present embodiment, fig. 7 to 14 are longitudinal sectional views, and the planar distribution of the metal reflective layer 260a is not shown in the above-described drawings. However, the metal reflective layers 260a are respectively located above the photodiodes 210 distributed in the array, and have no edge contact with each other. That is, the metal reflective layers 260a are disposed in a lattice shape on the surface of the second insulating layer 250.
The image sensor formed by the above embodiment includes: a semiconductor substrate 200; a photodiode 210; are located in the semiconductor substrate 200 and are formed separately; a first insulating layer 220 located on the surface of the semiconductor substrate 200 and covering the photodiode 210; metal plugs 230 separately arranged on the surface of the first insulating layer 220; an interlayer dielectric layer 240 on the surface of the first insulating layer 220 and covering the sidewalls of the metal plugs 230; a second insulating layer 250 on the surface of the interlayer dielectric layer 240; a reflective region 250a 'located in the second insulating layer 250 above the photodiode 210, wherein a surface of the reflective region 250 a' away from the photodiode is convex; a metal wiring region 250b in the second insulating layer 250 above the metal plug 230; a metal reflective layer 260a located on the reflective region 250a, wherein an upper surface of the metal reflective layer 260a is flush with a surface of the second insulating layer 250, a lower surface of the metal reflective layer 260a is connected with a convex surface of the reflective region 250a, and a lower surface of the metal reflective layer 260a is a concave surface; and a metal wire 260b located in the metal wire region 250b and electrically connected to the metal plug 230.
Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make modifications and variations of the present invention without departing from the spirit and scope of the present invention.
Claims (9)
1. A method of forming an image sensor, comprising:
providing a semiconductor substrate in which discrete photodiodes are formed;
forming a first insulating layer on the surface of the semiconductor substrate;
forming discrete metal plugs on the surface of the first insulating layer;
forming an interlayer dielectric layer on the surface of the first insulating layer, wherein the interlayer dielectric layer also covers the side wall of the metal bolt;
forming a second insulating layer on the surface of the interlayer dielectric layer;
etching the second insulating layer to form a reflecting region corresponding to the photodiode, wherein the surface of the reflecting region far away from the photodiode is a convex surface;
forming a metal layer on the second insulating layer, and covering the metal layer on the reflecting region;
and flattening the metal layer by adopting a chemical mechanical polishing process until the second insulating layer is exposed, forming metal wiring on the metal bolt, and forming a metal reflecting layer on the reflecting area, wherein the contact surface of the metal reflecting layer and the reflecting area is a concave surface.
2. The method as claimed in claim 1, wherein the convex surface of the reflective region has a radius of curvature of
3. The method of claim 2, wherein the etching of the convex surface on the reflective region is performed by dry etching, and the gas used comprises a CF series gas.
4. The method of claim 1, further comprising, at the same time as or before or after the forming of the reflective region:
and etching the second insulating layer to expose the metal bolt to form a metal wiring area.
5. The method of claim 1, wherein the metal layer material is copper or aluminum or tungsten.
6. The method of forming an image sensor as claimed in claim 1, further comprising, after forming the second insulating layer:
forming a hard mask layer on the second insulating layer;
etching the hard mask layer and defining a reflection area pattern;
forming a photoresist layer on the surface of the reflection region pattern;
annealing to form a convex surface on the surface of the photoresist layer;
and etching the second insulating layer along the photoresist layer by taking the hard mask layer as a mask.
7. The method of claim 6, wherein the annealing temperature is 180 ℃ to 240 ℃ and the annealing time is 50 seconds to 80 seconds.
8. An image sensor formed according to the method of any one of claims 1 to 7, comprising:
a semiconductor substrate;
the photodiodes are positioned in the semiconductor substrate and are arranged separately;
the first insulating layer is positioned on the surface of the semiconductor substrate;
the metal plug is positioned on the surface of the first insulating layer;
the interlayer dielectric layer is positioned on the surface of the first insulating layer and covers the side wall of the metal bolt;
the second insulating layer is positioned on the surface of the interlayer dielectric layer;
and the reflecting region is positioned in the second insulating layer above the photodiode, and the surface of the reflecting region, which is far away from the photodiode, is a convex surface.
9. The image sensor of claim 8, further comprising:
the metal reflecting layer is positioned on the reflecting area, the surface of the metal reflecting layer is flush with the surface of the second insulating layer, and the contact surface of the metal reflecting layer and the reflecting area is a concave surface;
and the metal wiring is positioned in the second insulating layer and is electrically connected with the metal bolt.
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| CN201810877186.7A CN108807447B (en) | 2018-08-03 | 2018-08-03 | Image sensor and forming method thereof |
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| CN201810877186.7A CN108807447B (en) | 2018-08-03 | 2018-08-03 | Image sensor and forming method thereof |
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| CN108807447B true CN108807447B (en) | 2020-12-18 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107154414A (en) * | 2017-05-27 | 2017-09-12 | 武汉新芯集成电路制造有限公司 | Back-illuminated cmos image sensors and preparation method thereof |
| CN108231811A (en) * | 2018-01-23 | 2018-06-29 | 中国电子科技集团公司第四十四研究所 | The microlens array of optical crosstalk between polarization imaging device pixel can be reduced |
| CN108269815A (en) * | 2018-01-10 | 2018-07-10 | 德淮半导体有限公司 | Cmos image sensor and forming method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107154414A (en) * | 2017-05-27 | 2017-09-12 | 武汉新芯集成电路制造有限公司 | Back-illuminated cmos image sensors and preparation method thereof |
| CN108269815A (en) * | 2018-01-10 | 2018-07-10 | 德淮半导体有限公司 | Cmos image sensor and forming method thereof |
| CN108231811A (en) * | 2018-01-23 | 2018-06-29 | 中国电子科技集团公司第四十四研究所 | The microlens array of optical crosstalk between polarization imaging device pixel can be reduced |
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