Influence Of Parameters On Indium Selenide Thin Films Fabricated By Magnetron Sputtering

belongs to III-VI compound semiconductor which is widely researched on their unique photoelectric properties attribute to2D layer structure. In2Se3has more than five structures named a, β,γ,δ and κ respectively. Owing to the free energy of formation are little between them, single-phase In2Se3is hard to obtain.In2Se3thin film prepared by the existing preparation crystallization is of poor quality and composition is deviating from the stoichiometric ratio. In2Se3thin film photovoltaic performances are different from each group. The preparation conditions of high quality single-phase In2Se3thin film are harsh. However, In2Se3thin films prepared by magnetron sputtering method have been seldom reported in the world.In this thesis, In2Se3thin films were prepared by magnetron sputtering method. Studies are concentrated on the membrane phase structure, composition, micro structure, transmittance and optical band gap which were controlled by sputtering power, substrate temperature, thickness, working pressure, and annealing conditions. The results show that:1. The sputtering power components have a significant impact on the films. When sputtering power are more than80W, the component of the deposited films are in line with the stoichiometric ratio. Substrate temperature determines the phase of the deposited films, As substrate temperature was rising from270℃to360℃, the predominate phase of films transformed from the K-In2Se3to γ-In2Se3phase. A pure phase of y-In2Se3thin film shows (00l) preferred orientation when substrate temperature is360℃. The film which has a band gap of2.0eV shows a hexagonal layer boundary clearly.2. The In2Se3thin film deposited at a low temperature is amorphous. After300℃annealing, thin films are crystallization and the optical absorption edge blue shift induced by the diffusion of Na. The content of Na contained in the thin film is closely related to the initial deposition temperature, After annealing, the amorphous In2Se3thin film deposited on190℃were showed gamma In2Se3thin film with a (00l) preferred orientation. The film formed density with an optical band gap for2.06eV.3. The phase remains a (00/) orientation of gamma In2Se3as the thickness of the film increased, And the surface topography by flat become coarse loose density as well as transmittance and optical band gaps occur "red shift", when the film thickness increased. Optical performance of thin films are under control.4. When work pressure increased, the thin film by γ-In2Se3transformed into κ-In2Se3predominate phase. The crystallization of the thin film of grain size is reduced and the optical band gap becomes smaller.