DOPING OF CHALCOGENIDE GLASSY SEMICONDUCTOR BY IMPLANTING NI IONS

An amorphous chalcogenide semiconductor, Pb(20)Ge(19)S(61)e6, has been doped by bombardment with 75 MeV Ni ions at fluences of 2 X 10(13) and 5 X 10(13) ions/cm(2), The ion-induced effect on the electronic properties of the bombarded and annealed semiconductor has been studied by measuring the de electrical conductivity and thermoelectric power, It is found that Ni atoms with incomplete electronic 3d shells induce deep trap states near the Fermi level which contribute to the electronic conduction process by a variable-range hopping mechanism, The carrier transport remains p-type in the bombarded (annealed) sample. However, significant changes in the temperature dependence of the thermoelectric power were observed. It is important to observe that a small fraction of the implanted Ni (0.2 at.%) introduced by ion-implantation at MeV energy can induce doping effects in bulk chalcogenide glass samples.