A deep-level defect, ER3, which was introduced into n-type material by high-energy (5.4MeV) He ions, was characterized by using deep-level transient spectroscopy. This defect, which was 0.196eV below the conduction band and had an apparent capture cross-section of 3.5 x 10-15cm2, was introduced at a rate of 3270/cm. The emission rate of the defect depended upon the electric-field strength in the space-charge region. This emission rate was modelled in terms of Poole-Frenkel distortion of a square well with a radius of 2nm or a Gaussian well with a characteristic width of 0.6nm. It was concluded that ER3 was a point defect which had a field dependence that was not explained by classical Poole-Frenkel enhancement.

Field-Enhanced Emission Rate and Electronic Properties of a Defect Introduced into n-GaN by 5.4MeV He-Ion Irradiation. S.A.Goodman, F.D.Auret, F.K.Koschnick, J.M.Spaeth, B.Beaumont, P.Gibart: Applied Physics Letters, 1999, 74[6], 809-11