We have deposited silicon nitride (SiN_x) films by plasma-enhanced chemical vapor deposition (PECVD) at 270 degree(s)C. Films are prepared by using silane (SiH₄) and ammonia (NH₃) source gases with hydrogen (H₂) or nitrogen (N₂) dilution. The film properties, including N/Si atomic ratio, hydrogen content, and the etching rate in 5% buffered HF are sensitive to the changes in dilution gases (H₂ or N₂) flow rate during deposition. For films with N/Si equals 1.33 (calculated by Rutherford backscattering, RBS); refractive index ((lambda) equals 6328 A) equals 2.0; hydrogen content equals 13% (calculated by Fourier transform infrared spectrometer, FTIR); and the etching rate in 5% buffered HF less than 50 A/min were achieved. In addition, the deposition rate of SiN_x films were dropped dramatically by adding dilution gases, especially with H₂ (from 4 A/sec to 1 A/sec). 3- inch 92,000 pixel elements a-Si:H TFT arrays with pre-mentioned high-quality SiN_x films as gate insulators have been manufactured. The interlayer short defects of the a-Si:H TFT matrix arrays can be reduced to 3 points by adding dilution gas.

Date Published: 27 October 1992
PDF: 7 pages
Proc. SPIE 1815, Display Technologies, (27 October 1992); doi: 10.1117/12.131311

Published in SPIE Proceedings Vol. 1815:
Display Technologies
Shu-Hsia Chen; Shin-Tson Wu, Editor(s)