Metallurgical structure of Be--Au and Si--Au ohmic contacts to GaP

Ohmic contacts obtained with Be--Au and Si--Au metallizations to p- and n-type GaP have been studied. Identification of the intermetallic compounds due to extensive Ga migration and some P migration within the alloyed contacts by transmission electron microscopy (TEM) and x-ray diffraction is discussed. The formation of intermetallic compounds was definitely established, and the situation for the Be--Au films alloyed with GaP was found to be more complicated than that for Si--Au films. Absolute concentrations for the various chemical species within the intermetallizations cannot be established. Results from other experiments are also presented to help elucidate the complex metallurgical structures