本研究所探討的主題是在低溫環境下利用二氧化碳雷射輔助電漿增強式化學氣相沉積系統進行高品質非晶矽及微晶矽薄膜的沉積，二氧化碳雷射的波長為10.6m，其中矽基薄膜的反應氣體甲烷(SiH4)對此波段的光具有相當高的吸收率，因而在沉積矽基薄膜同時將二氧化碳雷射導入，有助於甲烷(SiH4)的解離，因此可以在低溫環境沉積出微晶矽薄膜。本實驗將透過二氧化碳雷射輔助電漿增強式化學氣相沉積系統成長矽薄膜，進一步去分析不同雷射功率下所成長矽薄膜的緻密度、氫含量以及結晶率。一般的非晶矽薄膜太陽能電池，有一致命的缺點，為長時間照光後，轉換效率會大幅度的下降，此效應稱為光衰退(SWE)效應，如何降低此效應為各研究團隊的主要目標。利用二氧化碳雷射輔助電漿增強式化學氣相沉積系統成長出的高品質薄膜能有效降低此效應，在未加入雷射輔助前所沉積太陽能電池的光衰退率為-21%，而雷射加入後太陽能電池的光衰退率降至-8.3%，顯示雷射輔助所沉積出的微晶矽薄膜有助於降低光衰退率效應。

The topic of this research is silicon film deposited at low temperature based on Laser-assisted Plasma-Enhanced Chemical Vapor Deposition system (LAPECVD) to become high quality amorphous and microcrystal silicon film. The wavelength of CO2 laser is 10.6m. There are high absorption coefficient for SiH4 reactant gas at the wavelength. The CO2 laser beam is guided into chamber during deposition of silicon film. It assist SiH4 to dissociate therefore we could reduce temperature. The research would analyze the microstructure parameter、hydrogen bond concentration (NH) and crystalline volume fraction
(Xc) of LAPECVD's film. However, it is a critical disadvantage for the Si-based solar cells, the efficiency would reduce as the long term of light illumination.We call the disadvantage SWE. There are many groups research how to reduce the SWE constructively. The research could reduce the effect by the LAPECVD's higher quality film. After light illumination, the conversion efficiency degradation ratio of the solar cells deposited without and with laser-assistance decrease is -21% and -8.3%, respectively. These reseach verified that the Si films deposited by LAPECVD system could obtain higher stability of Si-based thin-film solar cells.

[1] H. F. Sterling, and R. C. G. Swann, 「Chemical vapor deposition promoted by r.f. discharge」 , Solid-state Electron, Vol. 8, pp. 653-654, 1965.

[2] W.E. Spear, and P.G. Le Comber, 「Substitutional doping of amorphous

silicon」, Solid State Commun.,Vol. 17, pp.1193-1196, 1975.
[3] W.E. Spear, and P.G. Le Comber, 「Electronic properties of substitutionally doped amorphous Si and Ge」, Phil. Mag., Vol. 33, pp. 935-949, 1976.
[4] 戴寶通、鄭晃忠, 「太陽能電池技術手冊,」 台灣電子材料與元件協會,
2008.
[5] D. L. Staebler, and C. R. Wronski, 「Reversible conductivity changes in discharge-produced amorphous Si」, Appl. Phys. Lett., Vol. 31, pp. 292-294, 1977.
[6] Y. L. Jiang and C. C. Kuo, "The I-V Characteristics of p/i/n a-Si:H Solar Cell with the I layer Deposited with Pulse Modulation RF Power", 1998 IEDMS, Dec. 20-23, Tainan, Taiwan,AP-28-P.243, 1998.
[7] Y. L. Jiang, M. J. Lee, and S. H. Chen "The Structural Evolution of a-Si:H Films Prepared by Pulse RF Power Modulation with Hydrogen and Helium Dilution", Materials Research Society Symposium Proceedings, Vol. 507, pp. 523-528, 1998
[8] Y. L. Jiang, K. S. Lin, C. C. Kuo, Y. C. Chang, L. S. Chu, C. H. Yu, C. C.
Lin, C. H. Tai, W. H.Tu, and K. A. Su, 「Controlling the silicon and hydrogen bonding configurations and its influence of photodegradation in a-Si:H pin solar cells」, Proceedings of IEDMS 2002, 20-21,Dec., Taipei, Taiwan, pp. 511-514, 2002.

[1] J. M. Seo, M. C. Jeong, and J. M. Myoung, 「Effects of hydrogen on
poly-and nano-crystallization of a-Si: H prepared by RF magnetron
sputtering」, J. Cryst. Growth, Vol. 295, pp. 119-123, 2006.
[2] S. Guha, and J. Yang, Scott J. Jones, Y. Chan ,and D. L. Williamson,
「Effect of microvoids on initial and light-degraded efficiencies of
hydrogenated amorphous silicon alloy solar cells」, Appl. Phys. Lett., Vol.
61, pp. 1444-1446, 1992.
[3] Y. L. Jiang, M. J. Lee, and S. H. Chen "The structural evolution of a-Si:H
films prepared by pulse RF power modulation with hydrogen and
helium dilution", Materials Research Society Symposium Proceedings,
Vol. 507, pp. 523-528, 1998
[4] Y. L. Jiang, K. S. Lin, C. C. Kuo, Y. C. Chang, L. S. Chu, C. H. Yu, C. C.
Lin, C. H. Tai, W. H.Tu, and K. A. Su, 「Controlling the silicon
and hydrogen bonding configurations and its influence of
photodegradation in a-Si:H pin solar cells」, Proceedings of IEDMS 20-21,
Dec.,Taipei, Taiwan, pp. 511-514, 2002.
[5] D. L. Staebler ,and C. R. Wronski, 「Reversible conductivity changes in
discharge-produced amorphous Si」, Appl. Phys. Lett., Vol. 31, pp. 292-294, 1977.
[6] John P, Odeh I M, Thomas M J K, el al. 「Determination of the hydrogen
content of a-Si films by infrared spectroscopy and 25 MeV α–particle
elastic scattering」, J Phys C, 14: 309~318, 1981.
[7] Ross R C, Tsong I S T, and Messier R. 「Quantification of hydrogen in
a-Si:H films by IR spectrometry」, N nuclear reaction, and SIMS . J Vac Sci Technol, 20: 406~409, 1982.
[8] S. Q. Xiao,S. Xu, D. Y. Wei, S. Y. Huang, H. P. Zhou, and Y. Xu. 「From amnorphous yo microcrystalline:Phase transition in rapid synthesis of hydrogenated silicon thin film in low frequency inductively coupled plasmas 」, JOURNAL OF APPLIED PHYSICS 108, 113520, 2010.
[9] J. Meier, E. Vallat-Sauvain, S. Dubail, U. Kroll, J. Dubail, S. Golay, L. Feitknecht, P. Torres, S. Fay, D. Fischer ,and A. Shah, 「Microcrystalline/micromorph silicon thin-film solar cells prepared by VHF-GD technique」, Sol. Energy Mater. Solar Cells, Vol. 66, pp. 73-84, 2001.
[10] A. V. Shah, J. Meier, E. Vallat-Sauvain, N. Wyrsch, U. Kroll, C. Droz ,and U. Graf, 「Material and solar cell research in microcrystalline silicon」 , Sol. Energy Mater. Solar Cells, Vol. 78, pp. 469-491, 2003.