Abstract

High-speed spatial light modulation using the electroabsorption effect in GaAs has been described recently (1,2). By controlling the charge level in a CCD well, the electric field, and therefore the optical absorption near the band edge, may be varied. This process suggests the possibility of electrically and optically programmable one and two-dimensional spatial light modulators operating at clock rates of as much as 1 GHz (3). One of the principle impediments to the realization of such devices is the lack of a high yield fabrication process that would make large area devices feasible. We have developed a new overlapping gate structure for Schottky barrier CCDs which has reduced photolithographic tolerances compared to current planar structures. Devices fabricated with this process have shown charge transfer inefficiencies in the low 10⁻⁴per transfer, a result which is among the best reported in GaAs.

© 1985 Optical Society of America