Abstract

The optical excitation of FETs gives insight into the dynamical processes ocurring within the device and is also of interest for evaluating the FET as a high-speed optical detector. Excitation by ultrafast optical pulses yields information on the transport and trapping of carriers on a picosecond time scale, and offers an alternative to pulsing the device in the conventional electronic manner. Use of the FET as an optical detector is potentially interesting because, in contrast to the PIN diode, gain can be obtained, without the extra noise associated with avalanche devices.¹ In addition, the output of a FET in an integrated circuit can be optically modulated, and in conjunction with electro-optic sampling this can be used for non-invasive diagnostics of fast GaAs ICs.² We have studied the electrical response of a submicron-gate GaAs FET to optical excitation by picosecond laser pulses.

© 1986 Optical Society of America