Effect of He on the optical and electrical properties of RF magnetron sputtered amorphous SiC:H films

• Published in: Journal of non-crystalline solids Vol. 376; pp. 81 - 85
• Main Authors: Saito, N., Fujita, M., Nakaaki, I., Yamawaki, S., Iwata, H., Nishioka, K.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 15.09.2013; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition; Deposition by sputtering; Direct current; Electrical properties; Exact sciences and technology; Growth from solid phases (including multiphase diffusion and recrystallization); Magnetron sputtering; Materials science; Methods of crystal growth; physics of crystal growth; Methods of deposition of films and coatings; film growth and epitaxy; Micro-crystallization; Optical properties; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Partial pressure; Physics; Resistivity; Silicon–carbon; Sputtering; Vapor phase epitaxy; growth from vapor phase; Silicon–carbon; Micro-crystallization; Magnetron sputtering; Methane; Photonic band gap; Electrical conductivity; Amorphous thin film; Electrical properties; Silicon-carbon; Crystallization; Infrared spectra; Carbon; Sputtering; Gas mixtures; Thin films; Cathode sputtering; Silicon alloys; Partial pressure; Optical properties; Physical vapor deposition; Chemical bonds; Reactive sputtering; Sputter deposition; Amorphous state structure; Radiofrequency sputtering
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2013.05.025

Hydrogenated silicon–carbon alloy (SiC:H) films were deposited by reactive RF magnetron sputtering of Si in methane–argon gas mixtures. As a second sputtering gas, helium was used to control the film properties. The effect of the partial pressure ratio (R) of He to the total sputtering gas on the structural, optical, and electrical properties of the films was investigated. At R values above 70%, the bonding configuration observed in the IR spectra changed, the optical band gap decreased, and the DC conductivity clearly increased. These observations imply an increase in structural disorder after introducing a high R of He during the sputtering process. In order to overcome the negative effects on the properties of films deposited under high R values, the possibility of micro-crystallization in an amorphous structure was examined by introducing H2 instead of He. •SiC:H films were prepared at different sputtering partial pressure (R) of He.•The films deposited at high R show the decrease of optical band gap and Si―H bonds.•Micro crystallization was observed by utilizing H2 at high R.