Near Ambient Pressure X-ray Photoelectron Spectroscopy Study of the Atomic Layer Deposition of TiO2 on RuO2(110)

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• 作者：Ashley R. Head ; Shilpi Chaudhary ; Giorgia Olivieri ; Fabrice Bournel ; Jesper N. Andersen ; Fran?ois Rochet ; Jean-Jacques Gallet ; Joachim Schnadt
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：January 14, 2016
• 年：2016
• 卷：120
• 期：1
• 页码：243-251
• 全文大小：449K
• ISSN：1932-7455

文摘

The atomic layer deposition (ALD) of TiO₂ on a RuO₂(110) surface from tetrakis(dimethylamido) titanium and water at 110 °C was investigated using near ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) at precursor pressures up to 0.1 mbar. In addition to the expected cyclic surface species, evidence for side reactions was found. Dimethylamine adsorbs on the surface during the TDMAT half-cycle, and a second species, likely methyl methylenimine, also forms. The removal of the amide ligand and the formation of an alkyammonium species during the water half-cycle were found to be pressure dependent. The O 1s, Ru 3d, and Ti 2p spectra show the formation of the Ru–O–Ti interface, and the binding energies are consistent with formation of TiO₂ after one full ALD cycle. Dosing TDMAT on the RuO₂(110) surface at room temperature promotes a multilayer formation that begins to desorb at 40 °C. The imine species is not seen until 60 °C. These insights into the ALD mechanism and precursor pressure dependence on reactivity highlight the utility of NAP-XPS in studying ALD processes and interface formation.