Effect of Deposition Temperature on Microstructure of Silicon Oxide Film Prepared by Plasma Enhanced Chemical Vapor Deposition

Abstract

Abstract: Hydrogenated silicon oxide (SiO_x:H) films were prepared by 13.56 MHz radio frequency plasma enhanced chemical vapor deposition (RF-PECVD). The effect of the deposition temperature (T) variation (from 50 ℃ to 400 ℃) on the film performance and microstructure were investigated. The T increases could induce the decreases of oxygen content (C_O) in the SiO_x:H film and at the same time make the film transform from nanocrystalline state to amorphous state gradually, which resulted in the film crystallinity (X_C) decreases and the film refractive index (n) increases. Further, it was found that the microstructure factor (R) decreases and the hydrogen content (C_H) in the SiO_x:H film increases first and then decreases with the T increases. A maximum of C_H could be obtained with an intermediate T. Based on the above results, the low-temperature formed film is considered as a typical composite with hydrogenated nanocrystalline silicon (nc-Si:H) inserted in the hydrogenated amorphous silicon oxide (a-SiO_x:H) matrix, however, the high-temperature deposited film consists of hydrogenated amorphous silicon (a-Si:H) matrix with nc-Si:H and a-SiO_x:H phases less and less diluted inside. The results show that excellent hydrogenated nanocrystalline silicon oxide (nc-SiO_x:H) film with high X_C and C_O for solar cell application should be deposited at a relatively low temperature.

Key words: silicon oxide film, nanocrystalline silicon oxide, PECVD, deposition temperature, crystallinity, oxygen content, hydrogen content

CLC Number:

TM914.4⁺1

YOU Jiachuan, ZHAO Lei, DIAO Hongwei, WANG Wenjing. Effect of Deposition Temperature on Microstructure of Silicon Oxide Film Prepared by Plasma Enhanced Chemical Vapor Deposition[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2021, 50(3): 509-515.

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