The influence of surface treatment on the surface properties of Cd0.99
Mn0.01Te gallium doped was studied. Using surface photovoltage spectro
scopy (SPS) we have investigated three types of the monocrystal surfac
es: polished with 'Gamal', etched in 5% Br-2/methanol and etched in KO
H/H2O. Changes in the electronic structure of Cd0.99Mn0.01Te:Ga surfac
es were observed. The temperature dependence of the band gap and surfa
ce states have been determined for each sample.