Radio Frequency Plasma Assisted Chemical Vapor Deposition Research Articles

Microstructure of highly oriented, hexagonal, boron nitride thin films grown on crystalline silicon by radio frequency plasma-assisted chemical vapor deposition

We present a high-resolution electron microscopy study of the microstructure of boron nitride thin films grown on silicon (100) by radio-frequency plasma-assisted chemical vapor deposition using B2H6 (1% in H2) and NH3 gases. Well-adhered boron nitride films grown on the grounded electrode show a highly oriented hexagonal structure with the c-axis parallel to the substrate surface throughout the film, without any interfacial amorphous layer. We ascribed this textured growth to an etching effect of atomic hydrogen present in the gas discharge. In contrast, films grown on the powered electrode, with compressive stress induced by ion bombardment, show a multilayered structure as observed by other authors, composed of an amorphous layer, a hexagonal layer with the c-axis parallel to the substrate surface and another layer oriented at random.

Field Emission from Pure and Nitrogen-Incorporated Diamond-Like-Carbon Films

Field emission from diamond-like-carbon (DLC) films grown on a silicon substrate has been investigated. The films were prepared using radio-frequency plasma-assisted chemical vapor deposition. A DLC film incorporated with nitrogen exhibited better emission characteristics. For both nitrogen-incorporated and pure DLC, electric arc between the film and anode drastically enhanced the emission current. Analysis showed that the arc induced the formation of silicon carbide and the change in the surface morphology. The possible mechanism of the enhanced emission is discussed.

Micromechanical Behaviour of Amorphous Hydrogenated Silicon Carbide Films

ABSTRACTAmorphous hydrogenated silicon carbide (a-Si1-xCx:H) films (x = 0.65 to 1) were deposited by radio frequency plasma assisted chemical vapour deposition (RF-PACVD). Their friction and wear properties were investigated by means of a conventional ball-on-disk apparatus. The results were correlated with film mechanical properties. It was found that adding silicon to a-C:H (also called diamond-like carbon (DLC)) films reduces the hardness, elastic modulus and internal stress values by 15 to 30 %. Scratch testing induces film spallation from stainless steel substrates at low loads (1 N). In the low normal load (1 N) ball-on-disk tests under humid N2 conditions, a-Si1-xCx:H films (0.7 < x < 0.9) combine a very low wear rate of both the film and the counterbody with a steady state low friction coefficient below 0.1. For higher loads (5 and 10 N), however, this low friction coefficient only lasts for a relatively short time. In this case, the harder diamond-like carbon films perform tribologically better because of their higher wear resistance, low wear rate of the counterbody and generally low friction coefficients between 0.15 and 0.35 in a humid ambient atmosphere. In a dry N2 atmosphere, pure DLC films perform tribologically better than a-S1-xCx:H films in all respects.