Optimization of Pulsed Annealing Techniques for GaAs Integrated Circuits

Ohmic contacts on GaAs were realized by pulse annealing AuGe and AuGe-Ni layers deposited on top of n-type GaAs conducting layers. We used focused and largediameter YAG laser beam pulses (λ =1.06 µm), a large diameter Ruby laser beam pulse (λ = 0.69 µm) and a largediameter electron beam pulse. We tested the electrical quality of the contacts obtained. We also examined the compatibility of the alloying techniques used with theself-alignment technology for IC fabrication. In particular, we tested the quality of Al Schottky diodes and of the boron implanted insulating regions which coexist on the same IC with the ohmic contacts and are subject to the same pulse annealing treatment. The relative merit of the different pulse treatments are discussed.