Deep centers, and the degradation of the electrical and optical properties of pseudomorphic high electron mobility transistors, were investigated by using deep-level transient spectroscopic, secondary ion mass spectrometric, photoluminescence and Van der Pauw techniques. It was shown that deep electron traps, with activation energies of Ec - 0.64 and Ec - 0.79eV (with larger capture cross-sections and densities), were strongly related to the O content and the photoluminescence intensity, and were held to be responsible for the degradation in electrical and optical properties. The experimental results also showed that H plasma could passivate or annihilate deep electron traps.

L.Lu, S.Feng, J.Liang, Z.Wang, J.Wang, Y.Wang, W.Ge: Journal of Crystal Growth, 1996, 169[4], 637-42