| 摘要 |
PURPOSE:To obtain a zinc sulfide film with a high quality and a low resistivity by a method wherein zinc compound is doped with iodine by using a specific quantity of hydrogen iodide in the method of forming the zinc sulfide film on a substrate by metal organic chemical vapor deposition(MOCVD). CONSTITUTION:A substrate made of, for instance, GaAs which provides excellent lattice matching with zinc sulfide is employed. As zinc compound, the combination of dimethyl zinc and hydrogen sulfide is recommended from the viewpoint of low temperature growth and, in order to obtain an especially high quality film, a low pressure MOCVD method is employed. A substrate temperature is normally 200-400 deg.C. The zinc compound and sulfur compound are supplied by a separated supply system through raw material supply inlets after being diluted by helium gas or the like respectively. Hydrogen sulfide is employed as iodine source in order to provide easy separating control obtain a low resistively. The hydrogen iodide is so supplied as to provide a mol ratio of 0.03-1.0 to the zinc compound. The partial pressure of the hydrogen iodide in a reaction chamber is 1.0X10<-4>-4.0X10<-3>. A very low resistivity of 2X10<-3>-5X10<-3>OMEGAcm can be obtained as the resistivity of a formed zinc sulfide film. |
