Depth profiles of Argon incorporated into Boron Nitride films during preparation and their temperature dependent evolution

• Published in: Diamond and related materials 2003, Vol.12 (1), p.37-46
• Main Authors: Deyneka, N., Zhang, X.W., Boyen, H.-G., Ziemann, P., Fukarek, W., Kruse, O., Möller, W.
• Format: Article
• Language: English
• Subjects: Boron Nitride; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Defects and impurities: doping, implantation, distribution, concentration, etc; Diffusion; Exact sciences and technology; Ion and electron beam-assisted deposition; ion plating; Ion-assisted deposition; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Rutherford backscattering; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/S0925-9635(02)00247-9

Cubic (c-) as well as hexagonal (h-) Boron Nitride (BN) films, prepared by different ion beam assisted deposition techniques on top of Si(0 0 1) substrates, were studied with respect to the depth profiles of incorporated Argon using Rutherford backscattering (RBS). Quantitative analysis of such RBS spectra clearly demonstrated a preferential trapping of Ar close to the substrate, where high resolution transmission electron microscopy revealed the presence of an amorphous intermixed and an h-BN layer on top of each other. Subsequent annealing steps at 730, 960 and 1100 °C combined with RBS allowed to determine the total amount of Ar diffusing out of a sample as well as the depth profiles of the residual Ar. For temperatures below 750 °C neither in c-BN nor in h-BN any Ar diffusion is observed. At 970 °C a clear outdiffusion of Ar is found in h-BN samples, while in c-BN a redistribution of the profiles occurs with a significant accumulation of Ar towards the surface. At 1100 °C, a loss of Ar becomes visible also for c-BN films and is attributed to grain boundary diffusion, while Ar trapped within c-BN grains appears still to be immobile.