1. Atomic layer deposition of transition metal chalcogenide TaSx using Ta[N(CH3)2]3[NC(CH3)3] precursor and H2S plasma.
- Author
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Deijkers, J. H., Thepass, H., Verheijen, M. A., Sprey, H., Maes, J. W., Kessels, W. M. M., and Mackus, A. J. M.
- Subjects
ATOMIC layer deposition ,COPPER ,TRANSITION metals ,DIFFUSION barriers ,SEMICONDUCTOR devices ,TANTALUM - Abstract
As a transition metal chalcogenide, tantalum sulfide ( TaS x ) is of interest for semiconductor device applications, for example, as a diffusion barrier in Cu interconnects. For deposition of ultrathin nanolayers in such demanding 3D structures, a synthesis method with optimal control is required, and therefore, an atomic layer deposition (ALD) process for TaS x was developed. ALD using (tert)-butylimidotris(dimethylamido)tantalum (Ta [ N (CH 3) 2 ] 3 [ NC (CH 3) 3 ]) as the precursor and an H 2 S-based plasma as the coreactant results in linear growth of TaS x films as a function of the number of cycles for all temperatures in the range 150–400 ° C with growth per cycle values between 1.17 ± 0.03 Å and 0.87 ± 0.08 Å. Saturation of the precursor and plasma dose times, established at 300 ° C, was reached after 20 and 10 s, respectively. Variation of the table temperature or the plasma composition offers the possibility to tune the film properties. At 300 ° C, amorphous TaS 3 films were grown, while addition of H 2 to the plasma led to polycrystalline TaS 2 films. The difference in sulfur content in the films correlates to a change in resistivity, where the least resistive film had the lowest S content. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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