Atomic Layer Deposition of Nickel Carbide from a Nickel Amidinate Precursor and Hydrogen Plasma

Abstract

A new atomic layer deposition (ALD) process for depositing nickel carbide (NiC ) thin films is reported, using bis( N, N'-di- tert-butylacetamidinato)nickel(II) and H plasma. The process shows a good layer-by-layer film growth behavior with a saturated film growth rate of 0.039 nm/cycle for a fairly wide process temperature window from 75 to 250 °C. Comprehensive material characterizations are performed on the NiC films deposited at 95 °C with various H plasma pulse lengths from 5 to 12 s, and no appreciable difference is found with the change of the plasma pulse length. The deposited NiC films are fairly pure, smooth, and conductive, and the x in the nominal formula of NiC is approximately 0.7. The ALD NiC films are polycrystalline with a rhombohedral NiC crystal structure, and the films are free of nanocrystalline graphite or amorphous carbon. Last, we demonstrate that, by using this ALD process, highly uniform NiC films can be conformally deposited into deep narrow trenches with an aspect ratio as high as 20:1, which thereby highlights the broad and promising applicability of this process for conformal NiC film coatings on complex high-aspect-ratio 3D architectures in general.

Atomic Layer Deposition of Nickel Using a Heteroleptic Ni Precursor with NH3 and Selective Deposition on Defects of Graphene

“…By contrast, an fcc Ni peak (indexed by PDF no.00-004-0850) is observed when NH 3 or H 2 is used as the reactant. Although the peaks (44.49° in H 2 -320 °C and 44.51° in NH 3 -320 °C) correspond exactly to the Ni(111) peak in the reference (44.51°, PDF no.00-004-0850), there is no experimental evidence from our data to completely rule out the interpretation of the broad peak reported by recent research, 36−38 which implies the coexistence of Ni 3 C peaks in the Ni(111) peak. This result further confirms that an oxygen-free reactant is indispensable for obtaining Ni metal films by ALD.…”

Control of Graphene Layer Thickness Grown on Plasma Enhanced Atomic Layer Deposition of Molybdenum Carbide

“…More work needs to be done in fine tuning MLG thickness by a study of the critical regimes of plasma time exposures, and more parameters should be looked at, specifically substrate thickness and crystallinity. In addition, other catalytic substrates should be evaluated, both as homogeneous elements and alloys, for suitability [17].…”

A Review on the Promising Plasma-Assisted Preparation of Electrocatalysts

“…Nickel carbide (Ni 3 C x ) films are prepared by the H 2 plasma atomic layer deposition technique. They are polycrystalline and highly homogeneous, with a rhombic Ni 3 C crystal structure, and without any nanographite or amorphous carbon [114]. Xiong et al [115] used the process to conformally coat a uniform thin layer of Ni 3 C on carbon nanotubes (CNTs), in order to obtain core-shell nanostructured Ni 3 C/CNT composites.…”