深槽隔离和倒金字塔阵列结构用于通过模拟提高 CMOS 图像传感器中光电二极管的光学效率。

Deep Trench Isolation and Inverted Pyramid Array Structures Used to Enhance Optical Efficiency of Photodiode in CMOS Image Sensor via Simulations.

机构信息

Department of Mechanical Engineering, National Cheng Kung University, Tainan 701, Taiwan.

Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan 701, Taiwan.

出版信息

Sensors (Basel). 2020 May 28;20(11):3062. doi: 10.3390/s20113062.

DOI:10.3390/s20113062

PMID:32481739

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7308853/

Abstract

The photodiode in the backside-illuminated CMOS sensor is modeled to analyze the optical performances in a range of wavelengths (300-1100 nm). The effects of changing in the deep trench isolation depth (DTI) and pitch size (d) of the inverted pyramid array (IPA) on the peak value () of optical efficiency (OE) and its wavelength region are identified first. Then, the growth ratio (GR) is defined for the change in these wavelength ranges to highlight the effectiveness of various DTI and d combinations on the and evaluate the difference between the pixel arrays with and without the DTI + IPA structures. Increasing DTI can bring in monotonous increases in the entire wavelength region. For a fixed DTI, the maximum is formed as the flat plane ( = 0 nm) is chosen for the top surface of Si photodiode in the RGB pixels operating at the visible light wavelengths; whereas different nonzero value is needed to obtain the maximum for the RGB pixels operating in the near-infrared (NIR) region. The optimum choice in d for each color pixel and DTI depth can elevate the maximum GR value in the NIR region up to 82.2%.

摘要

背面照明的 CMOS 传感器中的光电二极管经过建模，可分析各种波长（300-1100nm）下的光学性能。首先确定改变倒金字塔阵列（IPA）的深沟槽隔离深度（DTI）和间距大小（d）对峰值光学效率（OE）及其波长区域的影响。然后，定义生长比（GR）以突出不同 DTI 和 d 组合在和评估具有和不具有 DTI + IPA 结构的像素阵列之间的差异。增加 DTI 可以在整个波长区域带来单调的增加。对于固定的 DTI，当 RGB 像素中的 Si 光电二极管的上表面选择可见光波长下的平面（=0nm）时，会形成最大；而对于在近红外（NIR）区域工作的 RGB 像素，则需要不同的非零值才能获得最大。对于每个颜色像素和 DTI 深度的最佳 d 选择，可以将 NIR 区域的最大 GR 值提高到 82.2%。