Pulsed laser-induced single event upset and charge collection measurements as a function of optical penetration depth

We use picosecond laser pulses to investigate single event upsets and related fundamental charge collection mechanisms in semiconductor microelectronic devices and circuits. By varying the laser wavelength the incident laser pulses deposit charge tracks of variable length, which form an approximation to the charge tracks resulting from high energy space particle strikes. We show how variation of the charge track length deposited by laser pulses allows the mechanisms of charge collection in semiconductor devices to be probed in a sensitive manner. With the aid of computer simulations, new insight into charge collection mechanisms for metal–semiconductor field effect transistor (MESFET) devices and heterojunction bipolar transistor devices is found. In the case of the MESFET we point out the correlation between charge collection in the device and the ensuing single event upset in the composite circuit. In favorable cases, we show how probing circuits with tunable laser pulses can estimate a charge collection depth, which is a circuit parameter important for the prediction of error rates for circuits operating in a space-radiation environment.