Characteristics of BCl₃ plasma-etched GaN Schottky diodes

Schottky diode characteristics of a boron trichloride (BCl₃) plasma-etched n-GaN layer by reactive ion etching (RIE) were investigated using current-voltage measurements. BCl₃ plasma etching degraded the Schottky diode characteristics due to plasma-induced damage and a discharge-gas-related residue near the surface of the GaN layer. To remove the residue and plasma damage from the GaN layer, various surface treatments were carried out on the BCl₃ plasma-etched GaN layer. Improved Schottky characteristics were observed in nitrogen plasma-treated n-GaN Schottky diodes. X-ray photoelectron spectroscopy confirmed the removal of the discharge-gas-related residue.