Imagers using amorphous silicon thin film on application specific integrated circuit technology

As imaging systems become more demanding, the performance of image sensors has to keep pace with the development of computer components to process and store images. Besides resolution, color reproduction, dynamic range and speed, future image sensors are expected not only to provide raw signals, but to include part of the image processing system on-chip. Unlike charge coupled devices (CCDs) and complementary metal oxide semiconductor (CMOS) imagers, a sensor in thin film application specific integrated circuit (TFA) technology is a vertically integrated device. The thin film detector is fabricated independently of the application specific integrated circuit (ASIC) and is therefore not affected by ASIC scaling. Fill factors are commonly close to 100%. The technology offers high flexibility since an existing ASIC can be supplied with different detector structures for application specific device optimization. (C) 2000 Elsevier Science B.V. All rights reserved.