The chemical composition and band gap of amorphous Si:C:N:H layers

• Published in: Applied surface science 2016-05, Vol.371, p.91-95
• Main Authors: Swatowska, Barbara, Kluska, Stanislawa, Jurzecka-Szymacha, Maria, Stapinski, Tomasz, Tkacz-Smiech, Katarzyna
• Format: Article
• Language: English
• Subjects: Amorphous Si:C:N:H layers; Band gap; Band spectra; Bonding; Carbon; Chemical composition; Dielectrics; Ellipsometry; Optical constants; PACVD; Semiconductors; Silicon; Spectroscopic ellipsometry
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2016.02.198

[Display omitted] •Six type of amorphous hydrogenated films were obtained and analysed.•Investigated chemical bondings strongly influenced energy gap values.•Analysed layers could be applied as semiconductors and also as dielectrics. In this work we presented the correlation between the chemical composition of amorphous Si:C:N:H layers of various content of silicon, carbon and nitrogen, and their band gap. The series of amorphous Si:C:N:H layers were obtained by plasma assisted chemical vapour deposition method in which plasma was generated by RF (13.56MHz, 300W) and MW (2.45GHz, 2kW) onto monocrystalline silicon Si(001) and borosilicate glass. Structural studies were based on FTIR transmission spectrum registered within wavenumbers 400–4000cm−1. The presence of SiC, SiN, CN, CN, CC,CN, SiH and CH bonds was shown. The values band gap of the layers have been determined from spectrophotometric and ellipsometric measurements. The respective values are contained in the range between 1.64eV – characteristic for typical semiconductor and 4.21eV – for good dielectric, depending on the chemical composition and atomic structure of the layers.