Plasma-enhanced atomic layer deposition of silicon dioxide films using plasma-activated triisopropylsilane as a precursor

The plasma-enhanced atomic layer deposition (PEALD) process was developed as a growth technique of SiO2 thin films using a plasma-activated triisopropylsilane [TIPS, ((iPr)(3)SiH)] precursor. TIPS was activated by an argon plasma at the precursor injection stage of the process. Using the activated TIPS, it was possible to control the growth rate per cycle of the deposited films by adjusting the plasma ignition time. The PEALD technique allowed deposition of SiO2 films at temperatures as low as 50 degrees C without carbon impurities. In addition, films obtained with plasma ignition times of 3s and 10s had similar values of root-mean-square surface roughness. In order to evaluate the suitability of TIPS as a precursor for low-temperature deposition of SiO2 films, the vapor pressure of TIPS was measured. The thermal stability and the reactivity of the gas-phase TIPS with respect to water vapor were also investigated by analyzing the intensity changes of the C-H and Si-H peaks in the Fourier-transform infrared spectrum of TIPS. (C) 2014 American Vacuum Society.