Editors : F.G. Celii, O.J. Glembocki, S.W. Pang, F.H. Pollak, C.M.S. Torres
a1 Departamento de Fisica de Materiales, Facultad de Fisica, Universidad Complutense, 28040, Madrid, Spain
a2 Department of Physics, Indian Institute of Science, Bangalore - 560 012, India
a3 Solid State Physics Laboratory, Lucknow Road, Delhi - 110 054, India
a4 Departamentde Fisica de Materiales, Universidad Autonoma, C-IV, 28049 Cantoblanco- Madrid, Spain
Cathodoluminescence (CL) technique has been employed to study the optical properties of GaSb after deposition of hydrogenated amorphous silicon (a-Si:H). CL images recorded at various depths in the samples clearly show passivation of extended defects on the surface as well as in the bulk region. The passivation of various recombination centres in the bulk is attributed to formation of hydrogen-impurity complexes by diffusion of hydrogen ions from the plasma. Enhancement in luminescence intensity is seen due to passivation of non-radiative recombination centres. The passivation efficiency is found to improve with increase in a-Si:H deposition temperature.