Title :
Impact of CF4 Plasma Treatment on GaN
Author :
Chu, Rongming ; Suh, Chang Soo ; Wong, Man Hoi ; Fichtenbaum, Nicholas ; Brown, David ; McCarthy, Lee ; Keller, Stacia ; Wu, Feng ; Speck, James S. ; Mishra, Umesh K.
Author_Institution :
California Univ., Santa Barbara
Abstract :
We present a systematic study of the impact of CF4 plasma treatment on GaN. It was found that CF4 plasma etches GaN at a slow rate and yields a smooth etched surface. The effect of CF4 plasma on electrical characteristics of GaN metal-semiconductor field-effect-transistor structures shows that the CF4 plasma introduces acceptors into the near surface region of the GaN, which depletes mobile electrons. It was further demonstrated that leakage current of AlGaN/GaN (or GaN) Schottky diodes can be significantly suppressed by proper CF4 plasma treatment. These unique properties of CF4 plasma can be utilized for the advanced processing of GaN transistors.
Keywords :
Schottky gate field effect transistors; etching; field effect transistors; gallium compounds; leakage currents; plasma materials processing; wide band gap semiconductors; AlGaN; GaN; Schottky diodes; leakage current; metal-semiconductor field-effect-transistor; plasma treatment; Aluminum gallium nitride; Electric variables; Electron mobility; Etching; Gallium nitride; Leakage current; Plasma applications; Plasma materials processing; Plasma properties; Surface treatment; $hbox{CF}_{4}$ plasma; GaN; electron depletion; etch; leakage; transistor;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2007.902849
