13 March 2015 2.2um BSI CMOS image sensor with two layer photo-detector
Author Affiliations +
Abstract
Back Side Illumination (BSI) CMOS image sensors with two-layer photo detectors (2LPDs) have been fabricated and evaluated. The test pixel array has green pixels (2.2um x 2.2um) and a magenta pixel (2.2um x 4.4um). The green pixel has a single-layer photo detector (1LPD). The magenta pixel has a 2LPD and a vertical charge transfer (VCT) path to contact a back side photo detector. The 2LPD and the VCT were implemented by high-energy ion implantation from the circuit side. Measured spectral response curves from the 2LPDs fitted well with those estimated based on light-absorption theory for Silicon detectors. Our measurement results show that the keys to realize the 2LPD in BSI are; (1) the reduction of crosstalk to the VCT from adjacent pixels and (2) controlling the backside photo detector thickness variance to reduce color signal variations.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
H. Sasaki, A. Mochizuki, Y. Sugiura, R. Hasumi, K. Eda, Y. Egawa, H. Yamashita, K. Honda, T. Ohguro, H. S. Momose, H. Ootani, Y. Toyoshima, T. Asami, "2.2um BSI CMOS image sensor with two layer photo-detector", Proc. SPIE 9403, Image Sensors and Imaging Systems 2015, 940302 (13 March 2015); doi: 10.1117/12.2077122; https://doi.org/10.1117/12.2077122
PROCEEDINGS
6 PAGES


SHARE
Back to Top