MATERIAL CHARACTERIZATION AND OPTIMIZATION FOR ULTRAHIGH-SPEED METAL-SEMICONDUCTOR-METAL PHOTODETECTORS

Metal-semiconductor-metal photodetectors fabricated on different epita xial layers of GaAs err investigated and optimized for applications to high-speed optical transmission systems. The devices exhibit full wid th at half-maximum (FWHM) times from 1.5 ps to 7 ps corresponding to c arrier velocities exceeding 5 x 10(7) cm/s. In contrast to previously reported results, our results indicate that the use of low doped mater ials is recommended due to much better linearity and dynamic responsiv ity.