Effect of relative humidity on the crystallization of sol-gel lanthanum zirconium oxide films

The effects of relative humidity during the coating step on the texture and microstructure of sol-gel processed LZO thin films was investigated. X-ray diffraction patterns obtained for samples spin coated under relative humidity ranged from 10% to 80% and processed at 1100 °C for 15 min. The effect of humidity on the percentage of random polycrystalline material looked less exaggerated at lower temperatures. The reflection high energy electron diffraction (RHEED) patterns collected from samples processed at 900 °C and 1100 °C after coating showed a clean spot showing fully oriented material at both temperatures. The pattern obtained from the samples coated at 20% relative humidity are processed at 1100 °C showed a mixture of spots and rings suggesting a mixture of oriented and random material at the surface of the sample. It was observed that there is a threshold humidity level that is required for complete epitaxial nucleation and growth.