Characterization Of Zn/Au Back Contact To Lowdoped P-Inp

Abstract.

The mechanism behind the formation of alloyed ohmic contacts to p-type InP doped in the 1016 cm-3 range has been investigated. Techniques used for - characterising the contacts include the scanning electron microscope (SEM), specific contact resistance measurements, x-ray diffractometry (XRD), energy dispersive x-ray analysis (EDAX) and Auger electron spectroscopy (AES). Both temperature and time of annealing were varied during the study. The results obtained using our annealing procedures indicate that the optimum contact resistance is associated with the formation of an Au-In phase. The atomic percentage of indium increases with increasing annealing temperature whilst that of gold drops. Zinc phases appear only at the higher annealing temperatures used.