Image sensor structure and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-11276718-B2
Application number	US-201716618343-A
Country	US
Kind code	B2
Filing date	Jun 30, 2017
Priority date	Jun 29, 2017
Publication date	Mar 15, 2022
Grant date	Mar 15, 2022

Abstract

The present disclosure relates to an image sensor structure and a manufacturing method thereof. A detection structure layer and a blind pixel structure layer are used. The detection structure layer and the blind pixel structure layer are effectively combined and further formed by ion implantation. Thus, the space ratio of a single pixel is reduced, the integration and device sensitivity are improved, and the blind pixel array and the pixel array are also in the same environment, thereby further improving the detection sensitivity and reducing the detection error.

First claim

What is claimed is:

1. An image sensor structure which has an effective pixel array, wherein each effective pixel in the effective pixel array comprises: a detection structure layer and a blind pixel structure layer; wherein a first end of the detection structure layer and a first end of the blind pixel structure layer are jointly connected to a first shared extraction electrode, and a second end of the detection structure layer and a second end of the blind pixel structure layer are respectively connected to a second extraction electrode and a third extraction electrode.

2. The image sensor structure of claim 1 , wherein the detection structure layer adopts a first conductivity type sensitive material layer, and the blind pixel structure layer adopts a second conductivity type non-sensitive material layer; the first conductivity type and the second conductivity type are different.

3. The image sensor structure of claim 1 , wherein the top view of each effective pixel is triangular, and a first conductive beam, a second conductive beam, and a third conductive beam are disposed outside a triangle, and the first conductive beam, the second conductive beam, and the third conductive beam are parallel to three sides of the triangle respectively; the first end of the detection structure layer and the first end of the blind pixel structure layer are located at a first corner of the triangle, and are electrically connected to the first shared extraction electrode through the first conductive beam, and the second end of the detection structure is located at a second corner of the triangle, is connected to the second extraction electrode through a second conductive beam, and the second end of the blind pixel structure layer is located at a third corner of the triangle and is connected to the third extraction electrode through the third conductive beam.

4. The image sensor structure of claim 1 , wherein the detection structure layer and the blind pixel structure layer are arranged side by side in a serpentine shape and have space in between.

5. The image sensor structure of claim 1 , wherein the blind pixel structure layer is arranged inside or outside a surface of the detection structure layer.

6. The image sensor structure of claim 1 , wherein the effective pixel further comprises an undoped fin structure, and the detection structure layer and the blind pixel structure layer are respectively located on surfaces of the two sidewalls of the undoped fin structure.

7. The image sensor structure of claim 6 , wherein the undoped fin structure has at least two, and each of the undoped fin structures is arranged in parallel and has space in between.

8. The image sensor structure of claim 7 , wherein each fin structure has M sub-fin structures, wherein an amount of M−1 sub fin structures are arranged in parallel, wherein a remaining one of the sub-fin structures is perpendicularly intersected with each end of the M−1 sub-fin structures to form a comb-shaped structure; the comb-shaped fin structure comprises comb teeth and a trunk; and an outermost side of an outer surface of the comb teeth and an outer surface of the trunk are provided with the detection structure layer, and an inner side surface of the trunk and sidewalls of the comb teeth are provided with the blind pixel structure layer; or an outermost side of an outer surface of the comb teeth and an outer surface of the trunk are provided with the blind pixel structure layer, and an inner side surface of the trunk and sidewalls of the comb teeth are provided with the detection structure layer.

9. The image sensor structure of claim 7 , wherein an upper electrode layer of the detection structure layer connecting each fin structure is connected from a sidewall surface of the fin structure and led out; a lower electrode layer of the blind pixel structure layer connecting each fin structure is connected from a bottom of the fin structure and led out, alternatively, an upper electrode layer of the blind pixel structure layer connecting each fin structure is connected from a sidewall surface of the fin structure and led out; a lower electrode layer of the detection structure layer connecting each fin structure is connected from a bottom of the fin structure and led out.

10. The image sensor structure of claim 6 , wherein an injection barrier layer is also provided on top of the undoped fin structure.

Assignees

• Shanghai Ic R & D Center Co Ltd
• Shanghai Ic R&D Ct Co Ltd

Inventors

• Kang Xiaoxu

Classifications

• H10F39/011

  Manufacture or treatment of image sensors covered by group H10F39/12 · CPC title

• H10F39/184

  Infrared image sensors · CPC title

• H10F39/8023 Primary

  Disposition of the elements in pixels, e.g. smaller elements in the centre of the imager compared to larger elements at the periphery · CPC title

• H10F39/8027

  Geometry of the photosensitive area · CPC title

• H10F39/80 Primary

  Constructional details of image sensors · CPC title