Plasma-enhanced atomic layer deposition of carbon films employing a cyclic process of N2/H2 plasma and α, α’-dichloro-p-xylene as a precursor

• Plasma-enhanced atomic layer deposition (PE-ALD) for carbon films was realized. • The PE-ALD includes dichloro-p-xylene adsorption and N 2 /H 2 plasma modification. • Quantitative analysis of CH bending using in-situ FTIR is crucial to success. A novel concept and process were proposed for the plasma-enhanced atomic layer deposition (PE-ALD) of carbon films. α, α’-dichloro-p-xylene (DCX) was used to form the adsorption layer, which was modified using nitrogen/hydrogen (N 2 /H 2 ) plasma. Through iterative molecular chemisorption and end-group substitution processes, the selective and precise control of carbon deposition by PE-ALD was achieved. The growth per cycle of this process was estimated to be 0.02–0.05 nm/cycle. To determine the chemical reactions that occurred during the PE-ALD process, the IR spectra observed using in-situ Fourier transform infrared spectroscopy were analyzed. The decrease in the Si-OH bond at 3740 cm −1 and the saturation of the increase in CH bending at 1250 cm −1 revealed that the deposition of a DCX monolayer via a dehydrochlorination reaction with isolated OH bonding on SiO 2 has been successfully achieved. The change in N(−H) x stretching during the N 2 /H 2 plasma treatment indicated the substitution of exposed C-Cl bonding with C-NH 2 bonding on the chemisorbed DCX monolayer surface. Additionally, the composition of the carbon films after 200-cycle PE-ALD was analyzed. Finally, the realization of the concept for PE-ALD of carbon film was confirmed by surface analysis.