中国物理B ›› 2012, Vol. 21 ›› Issue (6): 66106-066106.doi: 10.1088/1674-1056/21/6/066106

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

Growth characteristics of amorphous-layer-free nanocrystalline silicon films fabricated by very high frequency PECVD at 250 ℃

郭艳青, 黄锐, 宋捷, 王祥, 宋超, 张奕雄   

  1. Department of Physics and Electronic Engineering, Hanshan Normal University, Chaozhou 521041, China
  • 收稿日期:2011-12-21 修回日期:2012-02-26 出版日期:2012-05-01 发布日期:2012-05-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 60806046), the Natural Science Foundation of Guangdong Province of China (Grant No. S2011010001853), and the FDYT (Grant No. LYM10099).

Growth characteristics of amorphous-layer-free nanocrystalline silicon films fabricated by very high frequency PECVD at 250 ℃

Guo Yan-Qing(郭艳青), Huang Rui(黄锐), Song Jie(宋捷), Wang Xiang(王祥), Song Chao(宋超), and Zhang Yi-Xiong(张奕雄)   

  1. Department of Physics and Electronic Engineering, Hanshan Normal University, Chaozhou 521041, China
  • Received:2011-12-21 Revised:2012-02-26 Online:2012-05-01 Published:2012-05-01
  • Contact: Guo Yan-Qing E-mail:yqguo@hstc.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 60806046), the Natural Science Foundation of Guangdong Province of China (Grant No. S2011010001853), and the FDYT (Grant No. LYM10099).

摘要: Amorphous-layer-free nanocrystalline silicon films were prepared by a very high frequency plasma enhanced chemical vapor deposition (PECVD) technique using hydrogen-diluted SiH4 at 250 ℃. The dependence of the crystallinity of the film on the hydrogen dilution ratio and the film thickness was investigated. Raman spectra show that the thickness of the initial amorphous incubation layer on silicon oxide gradually decreases with increasing hydrogen dilution ratio. High-resolution transmission electron microscopy reveals that the initial amorphous incubation layer can be completely eliminated at a hydrogen dilution ratio of 98%, which is lower than that needed for the growth of amorphous-layer-free nanocrystalline silicon using an excitation frequency of 13.56 MHz. More studies on the microstructure evolution of the initial amorphous incubation layer with hydrogen dilution ratios were performed using Fourier-transform infrared spectroscopy. It is suggested that the high hydrogen dilution, as well as the higher plasma excitation frequency, plays an important role in the formation of amorphous-layer-free nanocrystalline silicon films.

关键词: nanocrystalline silicon, amorphous incubation layer, plasma enhanced chemical vapor deposition

Abstract: Amorphous-layer-free nanocrystalline silicon films were prepared by a very high frequency plasma enhanced chemical vapor deposition (PECVD) technique using hydrogen-diluted SiH4 at 250 ℃. The dependence of the crystallinity of the film on the hydrogen dilution ratio and the film thickness was investigated. Raman spectra show that the thickness of the initial amorphous incubation layer on silicon oxide gradually decreases with increasing hydrogen dilution ratio. High-resolution transmission electron microscopy reveals that the initial amorphous incubation layer can be completely eliminated at a hydrogen dilution ratio of 98%, which is lower than that needed for the growth of amorphous-layer-free nanocrystalline silicon using an excitation frequency of 13.56 MHz. More studies on the microstructure evolution of the initial amorphous incubation layer with hydrogen dilution ratios were performed using Fourier-transform infrared spectroscopy. It is suggested that the high hydrogen dilution, as well as the higher plasma excitation frequency, plays an important role in the formation of amorphous-layer-free nanocrystalline silicon films.

Key words: nanocrystalline silicon, amorphous incubation layer, plasma enhanced chemical vapor deposition

中图分类号:  (Nanocrystalline materials)

  • 61.82.Rx
68.35.bj (Amorphous semiconductors, glasses)