MODIFICATION OF ELECTRICAL CHARACTERISTICS OF INDIUM TIN OXIDE/P-INP HETEROSTRUCTURES BY RAPID THERMAL ANNEALING

The effect of rapid thermal annealing on ITO/p-InP heterostructures was examined. In the as-deposited contacts the current conduction is dominated by recombination at low bias and by thermionic emission at high bias. Current in contacts annealed at 500 degrees C was dominated by thermionic emission for all values of bias. Annealing at 700 degrees C for 20 s caused the current conduction to be governed by tunnelling. This is explained as the result of diffusion of indium and tin atoms into InP. The net effect is the formation of a p(+)-layer. In contacts annealed at 500 degrees C barrier height increased by 60 meV, and in contacts annealed at 700 degrees C it decreased by 230 meV.