AMPLIFIED MOS IMAGER FOR SOFT-X-RAY IMAGING

This paper describes a new area sensor for soft X-rays, and its perfor mance. The operational principle is based on detecting the change in p otential of a floating photodiode caused by X-ray-induced electron-hol e pairs generation in a stacked amorphous silicon photoconversion laye r. The photoresponse was measured at wavelength from 50 Angstrom to 16 0 Angstrom. The signal to noise ratio of 28 dB was achieved, when the number of incident 70 Angstrom X-ray photons is as low as 230/pixel. Q uantum Efficiency (stored carriers / photon) at 70 Angstrom wavelength was 22. In addition, good reproducibility (< 10 % deviation) between different detectors and good reproducibility (< 20 % deviation) after ten months were also clarified. The performance of this area sensor in dicates its potential for detection of soft X-ray images.