Extended Infrared Photoresponse and Gain in Chalcogen-Supersaturated Silicon Photodiodes

摘要

Highly supersaturated solid solutions of selenium or sulfur in silicon were formed by ion implantation followed by nanosecond pulsed laser melting. pn+ photodiodes fabricated from these materials exhibit gain (external quantum efficiency, EQE, > 3000%) at 12 V of reverse bias, and substantial optoelectronic response to light of wavelengths as long as 1250 nm. The amount of gain and the strength of the extended response both decrease with decreasing magnitude of bias voltage, but >100% EQE is observed even at 2 volts of reverse bias. The behavior is inconsistent.