Hydride Vapor Phase Gan Films With Reduced Density Of Residual Electrons And Deep Traps

Electrical properties and deep electron and hole traps spectra are compared for undoped n-GaN films grown by hydride vapor phase epitaxy (HVPE) in the regular process (standard HVPE samples) and in HVPE process optimized for decreasing the concentration of residual donor impurities (improved HVPE samples). It is shown that the residual donor density can be reduced by optimization from similar to 10(17) cm(-3) to (2-5) x 10(14) cm(-3). The density of deep hole traps and deep electron traps decreases with decreased donor density, so that the concentration of deep hole traps in the improved samples is reduced to similar to 5 x 10(3) cm(-3) versus 2.9 x 10(16) cm(-3) in the standard samples, with a similar decrease in the electron traps concentration. (C) 2014 AIP Publishing LLC.