Bulk and surface properties of amorphous hydrogenated fluorinated silicon grown from SiF/sub 4/ and H/sub 2

• Published in: IEEE transactions on electron devices Vol. 36; no. 12; pp. 2853 - 2858
• Main Authors: Maruyama, A., Shen, D.S., Chu, V., Liu, J.Z., Campbell, I., Fauchet, P.M., Wagner, S.
• Format: Journal Article
• Language: English
• Published: IEEE 01.12.1989
• Subjects: Amorphous materials; Electromagnetic wave absorption; Glow discharges; Hydrogen; Mass spectroscopy; Optical films; Photoconductivity; Raman scattering; Silicon; Substrates
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/16.40946

A detailed study of the growth of amorphous hydrogenated fluorinated silicon (a-Si:H, F) from a DC glow discharge in SiF/sub 4/ and H/sub 2/ is discussed. The electrical properties of the films can be varied over a very wide range. The bulk properties of the best films that were measured included an Urbach energy E/sub u/=43 meV, a deep-level defect density N/sub s/=1.5*10/sup 15/ cm/sup -3/, and a hole drift mobility of 8*10/sup -3/ cm/sup 2/ V/sup -1/ s/sup -1/, which reflects a characteristic valence band energy of 36 meV. It was found that E/sub u/, N/sub s/, and the density of surface states N/sub ss/ are related to each other. Under the deposition condition of the films with the best bulk properties, N/sub ss/ reaches its highest value of 1*10/sup 14/ cm/sup -2/. It is suggested that in growth from SiF/sub 4//H/sub 2/, the density of dangling bonds at the growing surface is very sensitive to the deposition conditions.< >