Title :
Amplified MOS imager for soft X-ray imaging
Author :
Takayanagi, Isao ; Nagai, Koumei ; Tetsuka, Hisanori ; Inoue, Yuji ; Araki, Shuichi ; Mochimaru, Shouichirou ; Iketaki, Yoshinori ; Horikawa, Yoshiaki ; Matsumoto, Kazuya
Author_Institution :
Semicond. Technol. Center, Olympus Opt. Co. Ltd., Nagano, Japan
fDate :
8/1/1995 12:00:00 AM
Abstract :
This paper describes a new area sensor for soft X-rays, and its performance. The operational principle is based on detecting the change in potential of a floating photodiode caused by X-ray-induced electron-hole pairs generation in a stacked amorphous silicon photoconversion layer. The photoresponse was measured at wavelength from 50 Å to 160 Å. The signal to noise ratio of 25 dB was achieved, when the number of incident 70 Å X-ray photons is as low as 230/pixel. Quantum efficiency (stored carriers/photon) at 70 Å 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 indicates its potential for detection of soft X-ray images.
Keywords :
MOS integrated circuits; X-ray imaging; image sensors; photodiodes; 28 dB; 50 to 160 A; SNR; Si; X-ray-induced electron-hole pairs generation; amplified MOS imager; area sensor; floating photodiode; photoresponse; quantum efficiency; signal/noise ratio; soft X-ray imaging; stacked amorphous Si photoconversion layer; Amorphous silicon; Optoelectronic and photonic sensors; Photodiodes; Reproducibility of results; Sensor phenomena and characterization; Signal to noise ratio; Wavelength measurement; X-ray detection; X-ray detectors; X-ray imaging;
Journal_Title :
Electron Devices, IEEE Transactions on
