A half inch size CCD image sensor overlaid with a hydrogenated amorphous silicon

A half inch size CCD image sensor overlaid with a hydrogenated amorphous silicon (a-Si:H) as a photodetector has been designed and fabricated. The array consists of 506(V) × 404 (H) picture elements and the imaging area is 4.8(V)mm × 6.4(H)mm By employing the glow-discharged a-Si:H film for photoconductive film, high sensitivity of 0.014µA/x with IR filter (3200°K) and high S/N ratio more than 71dB for the fixed-pattern-noise was obtained. The S/N ratio of random noise is about 68dB. Smearing signal ratio is suppressed to 5% for incident light intensity of 5000 times of the saturation exposure. The blooming and highlight lag are completely suppressed by using CCD with vertical overflow drain (VOFD).