Author : Kenneth L. Klohn
Publisher :
Page : 17 pages
File Size : 21,79 MB
Release : 1968
Category :
ISBN :
Book Description
A study was made of various metals and metal alloys (Ag, Ni, In, and Au-Zn) which would make ohmic contacts to p- or n-type GaAs to determine the value of contact resistivity as a function of substrate impurity concentration. Contact resistivity values for p-type material varied from 1.2 x 10 to the -4th power ohm-cm sq for 2.8 x 10 to the 17th power/cc to 7.3 x 10 to the -7th ohm-cm sq for 9 x 10 to the 19th power/cc, and for n-type material from 2.5 x 10 to the -4th power ohm-cm sq for 1 x 10 to the 17th power/cc to 1.5 x 10 to the -5th power ohm-cm sq for 3 x 10 to the 18th power/cc. The metals were applied by evaporation or plating and followed by microalloying. The improvement in contact resistivity, as substrate impurity concentration increases, indicates the desirability of incorporating a thin, heavily doped region at the surface of a device by means of diffusion or epitaxy. The improvement in power output for a typical laser diode and its modified versions resulting from the reduction in R sub s is compared. (Author).