Isothermal and Two-Temperature Zone Selenization of Mo Layers

Glass/Mo, Mo foil, glass/Mo/In, and glass/Mo/Cu stacked layers were selenized in closed vacuum tubes by isothermal and/or two-temperature zone annealing in Se vapors. The selenization process was studied dependent on Se vapor pressure, temperature and time. Samples were selenized from 375 to 580 ° C for 30 and 60 minutes. The applied Se pressure was varied between 130 and4.4⋅103 Pa. The increase of MoSe 2 film thickness was found to depend on the origin of Mo. MoSe 2 thicknessdLon Mo-foil was much higher than on sputtered Mo layers, and it depended linearly on time and as a power functiondL~PSe1/2on Se vapor pressure. The residual oxygen content in the formed MoSe 2 layers was much lower in the two-zone selenization process. If Mo was covered with Cu or In before selenization, these were found to diffuse into formed MoSe 2 layer. All the MoSe 2 layers showed p -type conductivity.