부산대학교 도서관

A promising candidate for the wide field imaging spectrometer of the European Space Agency's X-ray Evolving Universe Spectroscopy (XEUS) mission is the Active Pixel Sensor (APS) based on the Depleted P-channel Field Effect Transistor (DEPFET). This concept combines low electronic noise with low power consumption, random accessibility of the pixels, high speed readout by parallel multi-channel processing, a fill factor of 100% by backside illumination and high quantum efficiency by an optimized entrance window and a fully depleted bulk. The DEPFET is a monolithic combination of detector and preamplifier with minimized capacitance and the possibility of repetitive non-destructive readout of the same signal thus reducing read noise. In this paper the DEPFET principle and the concepts of the APS and repetitive non-destructive readout are explained, measurements of single DEPFET structures and small APS prototypes are presented.