The electronic properties of defects introduced by low energy inductively coupled Ar plasma etching of n-type (Sidoped)GaAs were investigated by deep level transient spectroscopy (DLTS) and Laplace
DLTS. Several prominent electron traps (Ec—0.046 eV, Ec—0.186 eV, Ec—0.314 eV. Ec—0.528 eV and Ec—0.605 eV) were detected.The metastable defect Ec—0.046eV having a trap signature similar to E1 is observed for the first time. Ec—0.314eV and Ec—0.605 eV are metastable and appear to be similar to the M3 and M4 defects present in dc H-plasma exposed GaAs.