 |
ECOLE SUPÉRIEURE D'ÉLECTRICITÉ Une grande école d'ingénieurs au cœur des sciences de l'information,de l'énergie et des systèmes |
 |
Journal articles
Use of radio frequency power, silicon tetrafluoride and methane as parameters to tune structural properties of hydrogenated microcrystalline silicon carbon alloys
Abstract : In the search for a material with electrical properties similar to those of amorphous silicon or amorphous silicon germanium, but stable under light soaking, hydrogenated microcrystalline silicon–carbon alloy (µc-Si1 − xCx:H) thin films are a promising candidate. The interest in these materials lies in the possibility of varying the effective band gap by changing the amount of carbon in the alloy composition, while keeping a high crystalline fraction to maintain stability under light-soaking. In this study, µc-Si1 − xCx:H thin films were deposited by radio frequency (RF) plasma enhanced chemical vapour deposition using a silane and methane gas mixture highly diluted in hydrogen. Three deposition parameters were investigated as a means to control the film crystallinity: the RF power density, the methane flow rate and the presence of a small amount of silicon tetrafluoride in the gas mixture. Although all three parameters can result in materials with a Raman crystalline volume fraction above 50%, it is shown that they result in very different microstructures, as evidenced by x-ray diffraction and scanning transmission electron microscopy analyses. A growth model is proposed to explain the influence of each of these parameters on the final film structure.
https://hal-supelec.archives-ouvertes.fr/hal-01104321
Contributor : Thierry Leblanc <>
Submitted on : Friday, January 16, 2015 - 3:16:44 PM
Last modification on : Monday, December 14, 2020 - 12:29:06 PM
Contributor : Thierry Leblanc <>
Submitted on : Friday, January 16, 2015 - 3:16:44 PM
Last modification on : Monday, December 14, 2020 - 12:29:06 PM