Effect of Hydrogen Dilution Ratio and Substrate Roughness on the Microstructure of Intrinsic Microcrystalline Silicon Thin Films

Abstract:

Intrinsic microcrystalline silicon (μc-Si:H) thin films were deposited on four kinds of substrates (polished quartz glass: PG, Rough quartz glass: RG, Textured SnO₂:F coated glass: TG, Textured ZnO:Al coated glass: ZG) by 13.56 MHz plasma enhanced chemical vapor deposition (PECVD) with different hydrogen dilution ratio (R_H=H₂/SiH₄) under the pressure of 2 Torr. The film thickness, crystalline volume fraction (X_C) and substrate surface roughness (R_a) were measured by surface profilometer, Raman spectra and atom force microscopy (AFM), respectively. The results revealed that with the increase of R_H, the deposition rate decreased and X_C increased monotonously for the films deposited on the same substrate, but the substrate R_a had an obvious impact on the film microstructure. A physical model was proposed to illustrate the growth of the μc-Si:H thin films deposited on substrates with different R_a.

• Periodical: Advanced Materials Research (Volume 936)
• Pages: 202-206
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.936.202
• Online since: June 2014
• Authors: Bao Jun Yan*, Shu Lin Liu, Xiao Wei Liu, Ting Ting Jiang
• Keywords: Hydrogen Dilution Ratio, Microstructure, Silicon Thin Film, Substrate Roughness

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