29 May 2013 Flexible amorphous silicon PIN diode x-ray detectors
Author Affiliations +
A low temperature amorphous silicon (a-Si) thin film transistor (TFT) and amorphous silicon PIN photodiode technology for flexible passive pixel detector arrays has been developed using active matrix display technology. The flexible detector arrays can be conformed to non-planar surfaces with the potential to detect x-rays or other radiation with an appropriate conversion layer. The thin, lightweight, and robust backplanes may enable the use of highly portable x-ray detectors for use in the battlefield or in remote locations. We have fabricated detector arrays up to 200 millimeters along the diagonal on a Gen II (370 mm x 470 mm rectangular substrate) using plasma enhanced chemical vapor deposition (PECVD) a-Si as the active layer and PECVD silicon nitride (SiN) as the gate dielectric and passivation. The a-Si based TFTs exhibited an effective saturation mobility of 0.7 cm2/V-s, which is adequate for most sensing applications. The PIN diode material was fabricated using a low stress amorphous silicon (a-Si) PECVD process. The PIN diode dark current was 1.7 pA/mm2, the diode ideality factor was 1.36, and the diode fill factor was 0.73. We report on the critical steps in the evolution of the backplane process from qualification of the low temperature (180°C) TFT and PIN diode process on the 150 mm pilot line, the transfer of the process to flexible plastic substrates, and finally a discussion and demonstration of the scale-up to the Gen II (370 x 470 mm) panel scale pilot line.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Michael Marrs, Michael Marrs, Edward Bawolek, Edward Bawolek, Joseph T. Smith, Joseph T. Smith, Gregory B. Raupp, Gregory B. Raupp, David Morton, David Morton, "Flexible amorphous silicon PIN diode x-ray detectors", Proc. SPIE 8730, Flexible Electronics, 87300C (29 May 2013); doi: 10.1117/12.2015917; https://doi.org/10.1117/12.2015917


Low dark current and high dynamic range a Si H...
Proceedings of SPIE (March 05 2013)
Characteristics of a ceramic substrate x ray diode and its...
Proceedings of SPIE (September 25 2013)
X ray polarimeters based on silicon PIN diodes and drift...
Proceedings of SPIE (November 24 1999)
X-ray matrix sensors
Proceedings of SPIE (April 29 1999)
Thin Planar Epitaxial Silicon Detector For Synchrotron X-Rays
Proceedings of SPIE (November 26 1989)

Back to Top