Optical characteristics of hydrogenated amorphous silicon carbide films prepared at various gas flow rate ratios
Hydrogenated amorphous silicon carbide (a-SiC:H) films were prepared using a home-built plasma-enhanced chemical vapor deposition (PECVD) system with different flow rate ratios of methane (CH(4)) and silane (SiH(4)) gases. Fourier-transform infrared (FTIR) spectra indicate multiple bonding configura...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Article |
| Published: |
IOP Publishing
2007
|
| Subjects: | |
| Online Access: | http://eprints.um.edu.my/7366/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Hydrogenated amorphous silicon carbide (a-SiC:H) films were prepared using a home-built plasma-enhanced chemical vapor deposition (PECVD) system with different flow rate ratios of methane (CH(4)) and silane (SiH(4)) gases. Fourier-transform infrared (FTIR) spectra indicate multiple bonding configurations consisting of wagging, bending and stretching modes of silicon, hydrogen and carbon atoms with a steady depletion of Si-H wagging and stretching modes as the gas flow rate ratio increases. Micro-Raman spectra show evidence of amorphous silicon structure in all the films. Only the a-SiC:H film prepared at the highest CH(4) to SiH(4) gas flow rate ratio shows the existence of the Si-C vibrational mode. All the samples prepared show room-temperature luminescence with two peaks centered at 467 and 698 nm. The photoluminescence (PL) intensity increases as the CH(4) to SiH(4) gas flow rate ratio increases but a reduction in intensity is observed for a high CH(4) to SiH(4) gas flow rate ratio. a-SiC:H films with higher optical energy gaps were obtained by allowing the gases to flow at higher CH(4) to SiH(4) gas flow rate ratios. |
|---|