Nickel-gallium arsenide high-voltage power Schottky diodes

A power GaAs Schottky diode (SD) with a chemically deposited Ni barrier was designed, fabricated and tested. The diode has a reverse breakdown voltage V BR of 140 V, forward voltage drop V F (at 50 A/cm 2) of 0.7 V at 23°C, 0.5 V at 150°C and 0.3 V at 250°C, and reverse leakage current densities j R (at −50 V) of 0.1 μA/cm 2 at 23°C and 1 mA/cm 2 at 150°C. Calculated forward and reverse I– V characteristics using a simple self-consistent computer model are in good agreement with measured values. Calculated characteristics of a silicon SD with identical structure parameters, using the same model, show much poorer V BR, V F and j R values. The theoretical maximum value of V BR is physically limited by the largest allowed V F. For a V F of ⋍1.6 V, V BR.max is ⋍200 V in Si and ⋍800 simple technology allows manufacturing of large area GaAs Schottky diodes with average currents up to V in GaAs SDs. Our relatively 100 A.