Effect of selenization time on the growth of Cu2ZnSnSe4 thin films obtained from rapid thermal processing of stacked metallic layers

• CZTSe thin films were prepared by two-stage process.
• The selenization process was performed in a rapid heating furnace.
• Infrared active modes behavior of CZTSe film was first studied by IR spectroscopy.
• The loss of volatile elements during the RTP process is significantly reduced.
• For photovoltaic application, the film selenized with 20 min is more appropriate.

Cu2ZnSnSe4 (CZTSe) thin films were prepared by the stacked elemental layer technique with post rapid thermal processing. The effect of selenization time on the growth of CZTSe thin films has been studied. Energy dispersive X-ray measurement demonstrates that deviations of metal composition are slight between the final thin films and the precursor. The infrared active modes behavior of CZTSe films were first studied by Infrared Reflectance spectroscopy, which are in excellent agreement with the calculated values and the results of Raman scattering spectrum. X-ray diffraction and Raman scattering results indicate that the crystallinity of CZTSe thin film is improved with the increase of selenization time. However, for photovoltaic application, the film selenized with 20 min is more appropriate than the other films judging from the grain size and surface flatness.