Method for forming isolation grooves among pixels of CMOS (complementary metal oxide semiconductor) image sensor

Abstract

The invention relates to the technical field of semiconductor manufacturing, in particular to a method for forming isolation grooves among pixels of a CMOS (complementary metal oxide semiconductor) image sensor. According to the method, a blocking layer covers the surface of a bonded wafer, in addition, a lithography process and a first wet process etching process are adopted for etching a plurality of pattern windows in the blocking layer, in addition, the blocking layer is used as a mask for carrying out second wet process etching process processing on the wafer for replacing the traditional dry process etching process, a plurality of isolation grooves are formed, and subsequent oxide injection is carried out. According to the technical scheme, the problem of great electricity leakage current of a semiconductor device due to substrate damage caused by high-energy ion bombardment in the process of the traditional dry process etching process can be avoided, so the signal cross talk among the pixels of the CMOS image sensor can be reduced, and the photoelectric characteristics of the CMOS image sensor are enhanced.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a method for forming isolation trenches between pixels of a CMOS image sensor. Background technique [0002] With the continuous maturity and development of semiconductor manufacturing technology, CMOS image sensors are increasingly used in digital cameras, PC Cameras, video phones, third-generation mobile phones, video conferencing, intelligent security systems, car reversing sensors, toys and industrial, medical and other fields. [0003] CMOS image sensor belongs to optoelectronic components, because its manufacturing process is compatible with the existing integrated circuit manufacturing process, and its performance has many advantages over the original charge-coupled device (CCD), and it has gradually become the mainstream of image sensors. The driving circuit and the pixel can be integrated together, which simplifies the hardware design and reduces the...

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Problems solved by technology

[0008] In view of the above problems, the present invention provides a method for forming isolation trenches between pixels of a CMOS image sensor to solve the problem in the prior art that during the dry etching process, high-energy ions will damage the surface substrate, resulting in As for the defect that causes the leakage current of the semiconductor device to be large, which affects the photoelectric characteristics of the CMOS image sensor

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