Abstract
In this letter, the electrical characteristics of nanolaminate MgO/TiO 2 /MgO on a p-GaN MOS capacitor with and without postmetallization annealing (PMA) and NH 4 ) 2 S x treatments are investigated. With both PMA and NH 4 ) 2 S x treatments, the leakage current densities are reduced to 3.9× 10 -8 and 3.7× 10 -8 A/cm 2 at ±1 V, respectively. With a much-improved C-V curve, the effective dielectric constant of the gate dielectric stack for both treatments is 17.8, and an averaged interface trap density of 3.1× 10 11 eV -1 . cm -2 is obtained. © 2006 IEEE.