Study of Dielectric Caps for Incoherent Lamp Annealing of InP

Abstract

ABSTRACTA parametric study is presented of CVD and RF sputter deposited SiO2 and PSG dielectric caps for incoherent lamp annealing of InP. Both deposition and annealing parameters are studied. We observe that CVD caps provide reliable mechanical protection during lamp annealing up to maximum bulk temperatures of 830°C, while sputtered deposited SiO2 caps perform well ,up to 850°C. We find however that sputter deposited caps introduce process related conduction into both unimplanted and implanted semi-insulating InP. Electrical activation of implanted dopants is also studied as a function of capping technioue. Lamp annealing of InP protected by caps with CVD phosphorus doped SiO2 in contact with the InP surface, results in excellent activation efficiencies in Si+ implanted material. When properly capped and annealed, we observe electrical profiles whose shape more nearly approaches theoretical LSS, than those previously reported.