Properties of Si diodes prepared by alloying Al into n-type Si with heat pulses from a Nd:YAG laser

Abstract

p− n junctions have been prepared by locally alloying a vacuum-evaporated Al film into n-type Si with a focused heat pulse derived form a Nd:YAG laser. The preparation and the gross features of such junctions are described and electrical measurements of the forward bias and reverse bias current, reverse bias capacitance and transient response are given for room temperature. The forward and reverse bias current measurement show that charge recombination and generation within the depletion region controls the flow of current as would be expected for a Si junction. The reverse bias capacitance shows that the change in the doping profile in these junctions is abrupt. From the transient response the reverse recovery time is typically 0.5 × 10 −9 sec.