Amorphous silicon technology for large area digital X-ray and optical imaging

Abstract This paper will review amorphous silicon imaging technology in terms of the detector operating principles, materials-related process issues, and electrical and optoelectronic characteristics. Also, issues pertinent to pixel stability will be presented along with optimization of materials and processing conditions for reduced parasitics and leakage current, and enhanced mechanical integrity. Selected results are shown for X-ray and optical detectors, and integrated pixel structures. Extension of the current fabrication processes to low (∼120 °C) temperature, enabling fabrication of flexible imaging array (on plastic) substrates, will also be discussed along with preliminary results in terms of static characteristics of the active matrix switch.

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