Paper SS-ThP3
In situ Attenuated Total Reflectance and Transmission Fourier Transform Infrared Spectroscopy of (tetrakis)dimethylamido Hafnium (IV) Decomposition and Adsorption Dynamics on H-Si(100) Surface

Thursday, November 12, 2009, 6:00 pm, Room Hall 3

Low temperature atomic layer deposition (ALD) is favored for more uniform thin film. The authors have investigated the surface reaction mechanism of first step of Hf ALD agent tetrakis(dimethylamido)hafnium (TDMAH) reacting on the H-Si(100) surface for low temperature range 60-250ºC by in situ ATR-FTIR. The formation H-Hf species was observed in the chemisorbed layer and a gas phase initiated adsorption mechanism was hypothesized by ab initio calculation. In situ transmission FTIR will be used to monitor the gas phase decomposition dynamics and products of TDMAH. Two most possible reactions: insertion and β-hydride elimination are expected to be observed. Deuterium water prepared background will be used to verify the Hf-H species on H-Si(100). Interfacial bonds of Hf-N and Hf-Si are to be of about 1:1.5 in concentration from thermodynamic calculation. Minor C-Si bond from silylation by product is expected to be observed during desorption. Experimental measurement of decomposition rate will be compared with the ab initio kinetic data.