Abstract
We investigated the effects of recovery schemes on the characteristics of GaN Schottky diodes damaged by inductively coupled Cl2/H2/Ar/CH4 plasma etching. The recovery schemes included N2 plasma exposure, N2 plasma plus annealing at 600°C in N2. and annealing at 700°C in N2. Ga-deficient GaN surface layers were observed after etching the GaN, and the Ga/N stoichiometry at the surface was most strongly affected by the Cl2 flow rate among the process variables. The samples annealed at 700°C showed a clear improvement in diode characteristics and a complete restoration of the Ga/N ratio from ca. 0.87 to ca. 1.0 at the surface layers, as measured by Auger electron spectroscopy. For all other damage-recovery schemes, the samples showed no significant enhancement in diode characteristics and incomplete restoration of Ga/N stoichiometry at the surface layers.
Original language | English |
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Pages (from-to) | G592-G596 |
Journal | Journal of the Electrochemical Society |
Volume | 148 |
Issue number | 10 |
DOIs | |
State | Published - Oct 2001 |