Atomic layer deposition of HfO2 on (100) and (110) oriented silicon surfaces

FinFET devices require excellent coverage of the high-K dielectric as is provided by Atomic Layer Deposition (ALD) Because the HfO2deposition using HfCl4/H2O is controlled by the OH surface density, we studied the impact of crystallographic orientation of the silicon substrate on both its oxidation and HfO2nucleation. Whereas the (110) orientated substrate oxidizes faster than the (100) silicon, both substrate orientations display the same correlation between the initial HfO2growth and the thickness of the SiO2layer. This correlation is characterized by a linear increase, followed by saturation of the HfO2deposition once the SiO2thickness reaches approximately 0.4 nm. © The Electrochemical Society.

ISBN:9781566775700