The annealing treatment of interface states in planar and recessed-anode AlGaN/GaN Schottky barrier diodes

The recessed-anode AlGaN/GaN Schottky barrier diodes (SBDs) were fabricated by self-aligned process, and the effect of annealing of planar and recessed-anode AlGaN/GaN SBDs were investigated. The interface states of AlGaN/GaN SBD were treated by post anode annealing (PAA), which may be attributed to the reduction of metal-induced gap states (MIGS) at Schottky interface. The interface state density (N_SS) of planar and recessed-anode AlGaN/GaN SBDs are suppressed by PAA processes to 1.6 × 10¹³ eV⁻¹cm⁻² and 3.9 × 10¹⁴ eV⁻¹cm⁻², respectively. It is found that after annealing of AlGaN/GaN SBDs, the SBDs stability is enhanced, the leakage current is reduced, the ideal factor is optimized, and the ON-resistance is reduced. The PAA process can effectively improve the performance of AlGaN/GaN SBDs, which is a key technology to optimize GaN SBDs.