Pixel structure of CMOS (complementary metal-oxide-semiconductor transistor) image sensor and image sensor

Abstract

The invention discloses a pixel structure of a CMOS image sensor and the image sensor. The image sensor comprises four pixels, and the four pixels are arranged into a 2*2 pixel matrix type array structure; each pixel in the array structure is provided with a photodiode and a charge transfer transistor connected with the photodiode; two pixels in each column share a row selection transistor, a source following transistor, a reset transistor and a floating active area; a floating active area shared by each column is connected with charge transfer transistors of two pixels of the column and the source following transistor and the reset transistor of the column respectively; the row selection transistor and the source following transistor of the column are connected; and the reset transistor and the row selection transistor of the column are connected through signal transmission lines of the pixels of the column. According to the pixel structure and the image sensor, the opening rate of a metal window of the pixels can be effectively increased, and the image quality of a small-area pixel image sensor is improved.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, in particular to a pixel structure of a CMOS image sensor and the image sensor. Background technique [0002] Image sensors are already widely used in digital cameras, mobile phones, medical devices, automobiles and other applications. In particular, the rapid development of CMOS (Complementary Metal Oxide Semiconductor) image sensors has made people have higher requirements for low power consumption, small size, and high resolution image sensors. [0003] Because the pixel structure of the CMOS image sensor in the prior art depends on the structural characteristics of the pixel itself, its two-dimensional pixel array generally requires a row decoder to control the metal lines to be respectively connected to the gates of the charge transfer transistor, the row selection transistor and the reset transistor. Power supply metal lines and column pixel signal output metal lines are needed t...

AI Technical Summary

Problems solved by technology

However, due to the small photosensitive area and low sensitivity of the small-sized pixel sensor, the information transmitted under dark light is not clear enough, especially the use of multiple metal interconnection lines in the pixel array, resulting in a low opening ratio of the metal window and blocking part of the light incident on the photodiode

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