Anodic vacuum arc deposition of carbon and nitrogen containing carbon films

The anodic vacuum arc was used to deposit thin carbon films (a-C) on Si substrates. The arc produces a partially ionized carbon vapor plasma (less than 20% ionized) and is sustained by a consumable anode. Films with thickness around 0.8--1.7 microm were deposited with a deposition rate of 0.5 microm/min. The a-C films were modified by nitrogen plasma immersion ion implantation (PIII). The effects of nitrogen implantation on the structure and characteristics of the a-C films were investigated by x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and surface energy calculations from the contact angle measurements. XPS C 1s and N 1s spectra suggest a possible formation of covalent carbon-nitrogen bonds. The a-C films Raman spectra have a G band at 1,577 cm-1 and a D band at 1,350 cm-1, while the implanted films show a broad asymmetric peak around 1,500 cm-1. Surface energy analysis indicates that the nitrogen implanted films have lower interfacial tension with the silicon substrate