DEEP STATES AND SURFACE PROCESSES IN GaAs GROWN BY MOLECULAR BEAM EPITAXY

P. Blood , J. Harris , B. Joyce , J. Neave

We have used DLTS measurements to study the influence of growth conditions on the electron traps designated M1, M2, M3 and M4 which occur in MBE GaAs grown in the temperature range 520°C to 650°C. At an As:Ga ratio of 5:1 the concentrations of M1, M3 and M4 fall by two decades for growth temperatures increasing from 520°C to 650°C, whereas M2 has a more complex behaviour and is the dominant trap in 650°C grown layers. At a fixed growth temperature of 550°C concentrations of M1 and M4 fall with increasing As:Ga ratio whereas concentrations of M2 and M3 increase. The concentrations of M1 and M4 are also reduced by a factor 25 when Pb or hydrogen interact with the surface during growth. We argue that M1 and M4 are related, though not the same centre, and may be associated with As vacancies. M2 and M3 are different entities, neither of them related to M1 nor M4.

Domaines: Articles anciens

P. Blood, J. Harris, B. Joyce, J. Neave. DEEP STATES AND SURFACE PROCESSES IN GaAs GROWN BY MOLECULAR BEAM EPITAXY. Journal de Physique Colloques, 1982, 43 (C5), pp.C5-351-C5-355. ⟨10.1051/jphyscol:1982540⟩. ⟨jpa-00222260⟩