Author: Corinne GledelPublisher:
ISBN:
Category :
Languages : en
Pages : 253
Book Description
This work is essentially devoted to the synthesis and study of amorphous thin films obtained from lamellar crystalline materials such as LixV2 05 (0 ≤ x ≤ 0.2), M11PS3 (M= Mn, Fe, Ni, Cd, Sn and ln2/3)The achievement of materials presenting a correct stoichiometry has required the realization of a flash evaporation device operating at 1500° C and adapted to allow quenching of the vapor at liquid nitrogen temperature.The amorphous thin films have been characterized by, optical and electron scanning microscopy, microscopy, microprobre, UV-visible and I.R. spectroscopies.Their electrical conductivity has been studied and compared with the crystalline parent compounds.The local atomic arrangement (short range order) of several MPS3 films has been studied using the E.X.A.F.S.technique. Results show that the films have the same basic structure as the parent crystalline compounds, but deviati0ns are observed, depending on the metal M.The possibility of applying these films to design new photovoltaic devices has been examined. Amorphous V205 and LixV205 films have n type semiconducting properties and they lead to photosensitive p-n junction when deposited on to p type silicon wafers.Finally, we have examined the possibility of synthesing new amorphous M3Ps4 materials either by flash evaporation and by a novel soft chemistry, i.e. synthesis by reaction M ions in acetonitrile on the PS4 3- Ligand.
Author: Corinne Gledel