Amorphous silicon carbide thin films (a-SiC:H) deposited by plasma-enhanced chemical vapor deposition as protective coatings for harsh environment applications

• Published in: Thin solid films 2011-07, Vol.519 (18), p.5892-5898
• Main Authors: Daves, W., Krauss, A., Behnel, N., Häublein, V., Bauer, A., Frey, L.
• Format: Article
• Language: English
• Subjects: Amorphous materials; Amorphous silicon; Amorphous silicon carbide; Annealing; Chemical vapor deposition; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Cross-disciplinary physics: materials science; rheology; Deposition; Exact sciences and technology; Harsh environment; High temperature; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Passivation; Physics; Plasma-enhanced chemical vapor deposition; Protective coating; Protective coatings; Silicon carbide; Thin films
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2011.02.089

We investigated amorphous silicon carbide (a-SiC:H) thin films deposited by plasma-enhanced chemical vapor deposition (PECVD) as protective coatings for harsh environment applications. The influence of the deposition parameters on the film properties was studied. Stoichiometric films with a low tensile stress after annealing (< 50 MPa) were obtained with optimized parameters. The stability of a protective coating consisting of a PECVD amorphous silicon oxide layer (a-SiO x) and of an a-SiC:H layer was investigated through various aging experiments including annealing at high temperatures, autoclave testing and temperature cycling in air/water vapor environment. A platinum-based high-temperature metallization scheme deposited on oxidized Si substrates was used as a test vehicle. The a-SiO x/a-SiC:H stack showed the best performance when compared to standard passivation materials as amorphous silicon oxide or silicon nitride coatings.