Abstract
The growth of tungsten oxide (WO3) thin films by atomic layer deposition (ALD) offers numerous merits including atomic-scale thickness control at low deposition temperatures. In this work, we have developed and characterized a new plasma-enhanced ALD process for WO3 thin films using the metalorganic precursor (tBuN)2(Me2N)2W and O2 plasma as co-reactant over a wide temperature range of 100 °C-400 °C. The influence of deposition temperature on the growth behaviour and film properties is investigated in detail. The WO3 ALD process developed in this work yields a relatively high growth per cycle (GPC) which varies from ~0.7 Å at 100 °C to ~0.45 Å at 400 °C, as-determined by in-situ spectroscopic ellipsometry (SE). Rutherford backscattering spectrometry (RBS) measurements revealed a mass density of 5.9 g/cm3 and near stoichiometric film composition (O/W = 2.9). Both RBS and X-ray photoelectron spectroscopy (XPS) measurements confirmed no detectable C as well as N impurity incorporation. Grazing incidence X-ray diffraction (GI-XRD) measurements indicated that the films deposited at 400 °C were polycrystalline in nature.
Original language | English |
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Article number | 01B103 |
Number of pages | 7 |
Journal | Journal of Vacuum Science and Technology A: Vacuum, Surfaces, and Films |
Volume | 36 |
Issue number | 1 |
DOIs | |
Publication status | Published - 13 Jan 2018 |