Abstract

Amorphous silicon based sensor technology transcends the limits of conventional imaging and is the foundation for innovative solutions in radiology. Biometric detections, clean power generations, preventive security, bulk production monitoring, NDT (nondestructive testing) and PACS (picture archival and communication system) facilitated remote analysis etc, all benefits can be provided by AMFP (active matrix flat panel) hydrogenated amorphous silicon (a-Si:H) imaging sensors. Creative designs and innovative digital approach of a-Si:H sensors could ensure defined promise for exciting new generation of cost-effective, reliable, and real-time x-ray imaging pixel sensor. This research pursued to model such a visionary device to comply these challenges and to meet efficient, compact and flexible x-ray image detector into integral readout arena. In this thesis, primarily present a numerical model of transient photoresponse for a-Si:H pixel photodiode in active matrix 2-D environments. In numerical model, we considered all possible charge transport properties such as carriers drifting, trappings/de-trappings and recombination. The architecture configured as p-i-n structured a-Si:H photodiode and addressed by thin film pass transistor and integrated with charge storage capacitor. This work also includes quantitative study, test, and characterize the combined effects of the photodiode with varying geometry, and operating conditions by a customized simulator. The simulator code has written based on numerical model equations. Therefore, the simulator itself a model device and is operable in soft-hand environment to realize true device before fabrication. Our soft-hand experimental set up is based on indirect conversion principle and overall architecture is AMFP detection system.