Low temperature deposition of nanocrystalline TiO2 films: enhancement of nanocrystal formation by energetic particle bombardment

摘要

This paper reports the important role of energetic particle bombardment in achieving low temperature deposition of nanocrystalline TiO2 films by reactive DC magnetron sputtering of Ti targets in a mixture of argon and oxygen. In this work, we studied the effect of particle bombardment in the film deposition process by control of external processing parameters, including total pressure P-t and negative substrate bias V-b. The result shows that the variation of energetic particle bombardment has a significant impact on substrate temperature, crystal structure, surface morphology and refractive index n of deposited TiO2 films and we believe the process of non- equilibrium atomic scale heating caused by energetic particle bombardment is the main reason for the nanocrystal formation at low temperature ( below 75 degrees C).