Metal-semiconductor contacts for schottky diode fabrication

Abstract

This research demonstrates several methods to produce high voltage Schottky contact diodes. How contact construction and process temperatures affect turn-on voltage Schottky barrier height, on-resistance, and reverse breakdown voltage are studied. The performance of varied contact terminal construction types and temperature processes used to fabricate Schottky diodes were evaluated. The diodes are constructed of nickel metal mechanical (pressure) contacts and plasma sputter deposited nickel metal contacts on silicon carbide (SiC). Current-voltage characterizations were used to study the differences in performance verses geometric construction types, sputter deposition temperature, and annealing temperatures. The configurations studied were needle points, spheres, and planar metal-semiconductor contacts varying in interface areas that ranged from 0.58*10-4 to 6.2*10-4 cm2. Planar Schottky contacts 500 μm in diameter sputter deposited at 27C and 600C are exposed to a range of temperatures in ultra pure nitrogen atmosphere. These Schottky contacts were studied to gain insight into mechanical contacts, plasma sputter deposited contacts, and temperature processes.