Investigations of single-event upsets and charge collection in micro-electronics using variable-length laser-generated charge tracks

In this paper we examine how single-event upsets (SEU) and related charge collection characteristics in microelectronic circuits and devices depend on the depth of charge deposited by a picosecond laser pulse. Charge tracks of variable length are generated by tuning the laser wavelength through the semiconductor absorption spectrum. Our results show that the variable-length charge tracks provide a unique and sensitive probe of the charge collection volume of a micro-electronic circuit/device. In favorable cases we show how the wavelength tunability of the laser can be used to provide an experimental estimate of the charge collection depth.