Comparison of electronic structure and properties of hydrogen-associated and thermal double donors in silicon

Infrared (IR) and electron paramagnetic resonance (EPR) studies of quenching-dependent hydrogen-related double donor (HDD) formed in proton-implanted n-Si and p-Si upon annealing above 300°C were carried out. IR data taken at liquid He and N2 reveal that quenching-dependent IR absorption lines is due to HDD electronic excitations. An analysis of Si–H local vibrational modes and EPR data on AA1 EPR center allow to conclude that HDD is an interstitial-type complex with C2v-symmetry. There are similarities in structures and properties of HDD and thermal double donors (TDD). However, uniaxial stress-induced alignment and recovery kinetics of HDD (AA1 EPR center) show strong difference in comparison with TDD (NL8 EPR center).