Paper TF-ThP9
Interfacial Properties of Atomic Layer Deposited TiO₂ Films on InAs (100) Surfaces

Thursday, November 1, 2012, 6:00 pm, Room Central Hall

TiO₂ has been deposited on both native oxide and etched InAs (100) surfaces by thermal atomic layer deposition (ALD) from tetrakis dimethyl amido titanium (TDMAT) and H₂O. X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM) were utilized to study the interface between the TiO₂ films and the InAs substrate. For depositions at 200°C, the native oxide was thinned and part of the native oxide bubbled to the top of the TiO₂ surface. HRTEM data for a ~4 nm film of TiO₂ on InAs confirmed that the native oxide was completely removed from the interface. When TiO₂ was deposited on HF and NH₄OH etched InAs surfaces, practically sharp interfaces were maintained. To investigate the effect of temperature on the native oxide consumption, two sets of samples with film thickness of 2 and 3 nm were prepared at deposition temperatures ranging from 100 to 325°C. XPS showed that the native oxides were consumed most effectively at 250°C. Deviation of the deposition temperature from 250°C in either direction resulted in a reduction of the native oxide consumption rates.