Analysis on pressure dependence of microcrystalline silicon by optical emission spectroscopy

• Published in: Physica. E, Low-dimensional systems & nanostructures Vol. 33; no. 1; pp. 125 - 129
• Main Authors: Wu, Zhimeng, Sun, Jian, Lei, Qingsong, Zhao, Ying, Geng, Xinhua, Xi, Jianping
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.2006; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Elemental semiconductors; Exact sciences and technology; Microcrystalline silicon; Optical emission spectroscopy; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; Raman spectroscopy; VHF-PECVD; 68.55.−a; Microcrystalline silicon; Optical emission spectroscopy; 81.15.EF; VHF-PECVD; Raman spectroscopy; Raman spectra; Pressure effects; Amorphization; Photoluminescence; 68.55.-a; Deposition rate; Amorphous state; Deposition process; Dark conductivity; Hydrogen additions; Silicon; PECVD; High frequency; Microcrystal
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/j.physe.2005.12.165

Hydrogenated microcrystalline silicon films were prepared by very high-frequency plasma-enhanced chemical vapor deposition (VHF-PECVD) at 180 °C. The optical emission spectroscopy (OES) was used to monitor the plasma during the deposition process. When the pressure was enhanced from 50 to 80 Pa, the intensities of SiH*, H α* and H β* increase at first and then decrease for the pressures higher than 80 Pa. The transition from microcrystalline to amorphous phase occurs when increasing the pressure at silane concentration of 5%. It was found that the intensity ratio of I Hα*/ I SiH* affects the growth of microcrystalline silicon. With the increase of I Hα*/ I SiH* the crystallnity of films was improved. There are no direct relations between the SiH* intensity and the deposition rate. The deposition rate and dark conductivity are also discussed.