ELECTRICAL-PROPERTIES OF GAMMA-IN2SE3 LAYERS SYNTHESIZED BY SOLID-STATE REACTION BETWEEN IN AND SE THIN-FILMS

In2Se3 layers were obtained by solid state reaction induced by anneali ng between the In and Se constituents sequentially deposited in thin f ilm form. The annealing is carried out under a selenium atmosphere whi ch allows polycrystalline films of the gamma-In2Se3 phase to be obtain ed. Conductivity measurements show that five different behaviours are encountered depending on the history of the sample. After X-ray diffra ction and X-ray photoelectron spectroscopy measurements, the different behaviours are interpreted in terms of crystalline quality and contam ination of the layer with oxygen and/or carbon. The conductivity is co ntrolled by grain boundaries. When some contamination (intentional or otherwise) occurs, the properties of the grain boundary are modified, which explains the different behaviours of the layers.