No abstract

Ion implantation of transition metals into Si, followed by pulsed laser melting and rapid solidification, shows promise for making Si devices with sub-band gap optoelectronic response. We study Si implanted with Au at doses ranging from 1015 – 1016 at./cm2, with all but the lowest dose exhibiting interface breakdown during solidification, resulting in heavily defected layers. Terahertz photocarrier lifetime measurements confirm that layers with breakdown show recombination lifetimes of about 100 ps, compared to 800 ps for a layer with no breakdown. Device measurements, however, show more photoresponse at 1550 nm in a layer with breakdown than in a layer without. The results suggest that avoiding breakdown may be desirable but might not necessarily be imperative for making a useful device.

No abstract

No abstract

Thin film Cu(In,Ga)Se 2 (CIGS) layers were deposited by a 1-stage and 3-stage coevaporation process on Mo/Glass substrates at various Ga/(Ga+In) ratios (Ga ratio). The sputter rate and the depth profile of 1-stage CIGS absorber layers at various Ga ratios were measured using secondary ion mass spectrometry (SIMS) using different primary voltages and angles of incidence of a Cs beam in order to study how the Ga ratio of CIGS affected the sputter rate. It was determined that there was up to 50% variation in film sputter rate depending on the Ga ratio range, SIMS primary voltage, and angle of incidence. A point-by-point correction method was then developed to correct for relative sputter rate differences in 3-stage CIGS samples with a graded Ga ratio profile.