A high-sensitivity broadband image sensor using CuInGaSe<inf>2</inf> thin films

Abstract

We have fabricated a novel CMOS image sensor using polycrystalline CuInGaSe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (CIGS) thin films as an absorber layer, which outperforms conventional crystalline Si (c-Si) CMOS image sensors regarding higher external quantum efficiency(EQE) and wider spectral sensitive range. Development of this image sensor has been realized due to dark current suppression by the combination of microfabrication processes of LSI and solar cell fabrication technologies. The newly developed CIGS image sensors were capable to capture night scenes. Image sensors with 352 (H) times 288 (V) pixels (CIF), and 640 (H) times 480 (V) pixels (VGA) with each pixel size of 10 mum times 10 mum, have been fabricated.