Manufacturing method of CMOS image sensor

Abstract

The invention discloses a manufacturing method of a CMOS image sensor. A forming method of a pixel high-energy ion implantation region comprises the following steps of: 1, forming a liner oxide layer; 2, forming second dielectric layers made of different materials on the surface of the liner oxide layer, and overlapping the second dielectric layers to form a masking layer; 3, forming a photoresist pattern by adopting a photoetching process to open the pixel high-energy ion implantation region; and 4, performing high-energy ion implantation to form a pixel high-energy ion implantation region, and improving the blocking capability of the masking layer on the channel effect by utilizing the characteristic that the second dielectric layer and the liner oxide layer in the masking layer are different in material. According to the manufacturing method, the quality of the pixel high-energy ion implantation region can be improved, and the trailing depth of the pixel high-energy ion implantation region can be reduced.

Description

technical field [0001] The invention relates to a method for manufacturing a semiconductor integrated circuit, in particular to a method for manufacturing a CMOS image sensor (CMOS Image Sensor, CIS). Background technique [0002] With the continuous development of the semiconductor industry, the integrated circuit manufacturing process is just like Moore's Law (the number of integrated components on the chip doubles about every 18 months). The device density continues to increase, the performance continues to improve, and the popularity of computers, communications and consumer electronics, Greatly improve economic productivity and quality of life. Among them, CMOS image sensor chips are widely used and the market demand is huge. Subsequently, the performance requirements of CIS products are also higher. The existing CMOS image sensor is composed of a pixel (Pixel) unit circuit and a CMOS circuit, the pixel (Pixel) unit circuit is located in the pixel area (Pixel area), and...

AI Technical Summary

Problems solved by technology

However, for the N-type region of the photodiode or the pixel isolation structure corresponding to the deeper junction depth of the CIS, the ion implantation energy is too high, such as the peak value of the corresponding implantation depth is more than 1 micron, and the pad oxide layer still has a large The channel effect finally makes the high-energy ion implantation area of ​​the pixel produce a deep tailing area

Images