Single-source Precursor Based ZnSe Thin Film Preparation through MOCVD Method

In conclusion, two new single-source precursors for ZnSe thin film were synthesized and characterized. Both precursors were found to have improved thermal properties of relatively very low melting and decomposition temperatures, which are quite suitable in their application to a window layer material through MOCVD method. Using these precursors, ZnSe thin films were successfully deposited on various substrates with a relatively large growth rate. ZnSe is a well-known II-VI n-type semiconductor material with a 2.7 eV band gap, which can be used for buffer layer for Cd-free CIS type solar cells, light emitting diode, and thin film transistors. For these uses, various efforts to develop ZnSe films have been carried out using different methods such as chemical bath deposition (CBD), atomic layer deposition (ALD), successive ionic layer adsorption and reaction (SILAR), pulse plating technique, and metal organic chemical vapor deposition (MOCVD) methods. So, there have been many attempts to make ZnSe films through MOCVD since it is known as one of the reliable methods that can produce homogeneous and well-packed thin films. In the beginning, alkyl zinc and alkyl selenides were used, but they were too reactive or very toxic to handle. Accordingly, various single-source precursors were developed to make ZnSe thin films. Among them, dis-elenocarbamate type compounds were widely investigated for the preparation of ZnSe films after the research by O'Brian et al. and especially, by adopting asymmetric alkyl groups, they could be used for ZnSe films through MOCVD under relatively milder conditions