%0 Journal Article
%T Full well capacity and quantum efficiency optimization for small size backside illuminated CMOS image pixels with a new photodiode structure<br>一种用于优化小尺寸背照式CMOS图像传感器满阱容量与量子效率的新型光电二极管结构
%A Sun Yu
%A Zhang Ping
%A Xu Jiangtao
%A Gao Zhiyuan
%A Xu Chao
%A <br>孙羽
%A 张平
%A 徐江涛
%A 高志远
%A 徐超
%J 半导体学报
%D 2012
%I 
%X To improve the full well capacity (FWC) of a small size backside illuminated (BSI) CMOS image sensor (CIS), the effect of photodiode capacitance (CPD) on FWC is studied, and a reformed pinned photodiode (PPD) structure is proposed. Two procedures are implemented for the optimization. The first is to form a varying doping concentration and depth stretched new N region, which is implemented by an additional higher-energy and lower-dose N type implant beneath the original N region. The FWC of this structure is increased by extending the side wall junctions in the substrate. Secondly, in order to help the enlarged well capacity achieve full depletion, two step P-type implants with different implant energies are introduced to form a P-type insertion region in the interior of the stretched N region. This vertical inserted P region guarantees that the proposed new PD structure achieves full depletion in the reset period. The simulation results show that the FWC can be improved from 1289e- to 6390e-, and this improvement does not sacrifice any image lag performance. Additionally, quantum efficiency (QE) is enhanced in the full wavelength range, especially 6.3% at 520 nm wavelength. This technique can not only be used in such BSI structures, but also adopted in an FSI pixel with any photodiode-type readout scheme.
%K backside illuminated CMOS image sensor
%K photodiode
%K full well capacity
%K quantum efficiency
%K small size pixel<br>背照式CMOS图像传感器
%K 光电二极管
%K 满阱容量
%K 量子效率
%K 小尺寸像素.
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=5B3AB970F71A803DEACDC0559115BFCF0A068CD97DD29835&cid=1319827C0C74AAE8D654BEA21B7F54D3&jid=025C8057C4D37C4BA0041DC7DE7C758F&aid=3A1389981F843183FBE94E28A548E7A3&yid=99E9153A83D4CB11&vid=27746BCEEE58E9DC&iid=59906B3B2830C2C5&sid=96A6D7C3E2F5FB3A&eid=DF92D298D3FF1E6E&journal_id=1674-4926&journal_name=半导体学报&referenced_num=0&reference_num=13