Electrical characterization of gallium nitride mis capacitors with an oxide/nitride/oxide gate dielectric synthesized by jet vapor deposition

MIS capacitors are demonstrated on both unintentionally-doped and Si-implanted GaN samples. The multi-layer SiO2/SiN/SiO2 gate dielectric employed in these capacitors was synthesized using the jet vapor deposition technique. Test capacitors show good charge modulation at room temperature and record breakdown fields for insulators on GaN. In addition, the capacitor leakage current density is below 10 mu A/cm(2) at 12.5 MV/cm, even for temperatures as high as 600 K. These and other preliminary results reported herein suggest that SiO2/SiN/SiO2 stacks synthesized by jet vapor deposition are an excellent choice for the gate dielectric in high-power, high-frequency GaN MISFETs.