A 2 M pixel HDTV CCD image sensor with tungsten photo-shield and H-CCD shunt wiring

A 1-in optical lens format, 2-Mpixel FIT-CCD (charge coupled device) image sensor is described. The low reflectance and good step coverage characteristics of a tungsten photoshield, combined with a frame-interline-transfer scheme, reduces the smear level to -110 dB. The tungsten photoshield also acts as a shunt bus line, supplying transfer pulses to vertical CCD (V-CCD) electrodes, so that a 1.2*10/sup 5/-electron charge-handling capability is obtained at a frame transfer frequency of 1 MHz. Tungsten-and-aluminum-shunt (TAS) wiring, used in a horizontal CCD (H-CCD), suppresses vertical line pair fixed-pattern noise, even at a smaller transfer pulse amplitudes. TAS wiring also helps reduce power consumption in the H-CCD by 2/3 compared to that achieved with conventional wiring.<
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