In situ infrared spectroscopy of hafnium oxide growth on hydrogen-terminated silicon surfaces by atomic layer deposition -: art. no. 133103

The interface formation between HfO2 and H-terminated Si(111) and Si(100) is studied by in situ infrared absorption spectroscopy during atomic layer deposition using alternating tetrakis-ethylmethylamino hafnium (TEMAH) and deuterium oxide (D2O) pulses. The HfO2 growth is initiated by the reaction of TEMAH with Si-H rather than D2O, and there is no evidence for SiO2 formation at moderate growth temperatures (similar to 100 degrees C). Although Rutherford backscattering shows a linear increase of Hf coverage, direct observations of Si-H, Si-O-Hf, and HfO2 phonons indicate that five cycles are needed to reach the steady state interface composition of similar to 50% reacted sites. The formation of interfacial SiO2 (similar to 0.7 nm) is observed after postdeposition annealing at 700 degrees C in ultrapure nitrogen. (C) 2005 American Institute of Physics.