背照式CMOS图像传感器像素结构影响分析

Analysis for the Influence of Pixel Structure in Backside Illuminated CMOS Image Sensor

本文使用Ansys Lumerical FDTD软件建立了BSI-CIS工艺的仿真模型,利用该模型基于55 nm BSI-CIS工艺,针对2 um和2.79 um尺寸的像素单元,对850 nm、940 nm波段不同CDTI图形结构的量子效率值进行仿真,从而获得各自近红外吸收最高的CDTI图形结构,该结构可在850 nm波长获得45%以上的量子效率。

A back-side illuminated CMOS (BSI-CMOS) simulation model based on Ansys Lumerical FDTD was proposed. The Quantum Efficiency (QE) of 2 um and 2.79 um pitch pixel on different CDTI graphic design structures in 850 nm, 940 nm waveband were simulated and studied for 55 nm BSI-CIS process. The simulation results showed that the CDTI graph structure with the highest near-infrared absorption can be obtained, and the quantum efficiency of the structure can be more than 45% at 850 nm wavelength.