Effect of O2 addition on the deposition of Pt thin films by metallorganic chemical vapor deposition

Platinum thin films were deposited on SiO2/Si substrates at a deposition temperature of 325°C by metallorganic chemical vapor deposition using Pt-hexafluoroacetylacetonate as a precursor. It was found that the addition of the proper amount of O2 gas was essential to deposit high-quality Pt thin films. Dense Pt thin films with smooth surfaces and high electrical conductivity were deposited above a critical O2 flow rate of 50 sccm. The introduction of O2 gas made the Pt films partially oxidized, resulting in the reduction of their surface and grain boundary energy. Therefore, wettability of the Pt thin films on SiO2/Si was improved and the grain growth of the films by a postdeposition annealing was suppressed as the addition of O2 was increased during the deposition.