由於透明導電膜的高導電性及可見光高穿透率特性，使其在太陽能電池的應用中作為透明電極，並且於透明導電膜表面進行粗糙化，可使得入射光於界面造成散射，增加光在吸收層的路徑，形成光陷化效應(light trapping effect)，提高光吸收效率，進而提昇太陽能電池的效率。
本研究使用透明導電氧化物為二氧化錫，其以濺鍍法製備二氧化錫薄膜。主要針對二氧化錫薄膜進行化學蝕刻，以進行表面粗糙化，分別討論熱處理前後對二氧化錫薄膜蝕刻效果的影響，以及不同濺鍍壓力之二氧化錫薄膜其蝕刻效果的影響。另外，也在玻璃基材表面以光微影製程輔助蝕刻進行規則化圖案的製備，再進行二氧化錫的濺鍍，探討規則化圖案對光散射的效果。
實驗結果顯示，經過熱處理能提昇二氧化錫薄膜的導電率及光穿透率，對熱處理後之二氧化錫薄膜進行蝕刻，結果並不對薄膜表面粗糙度及霧度值造成影響，這是因為熱處理提昇了薄膜的緻密性，增加其抗蝕刻能力；相反的，蝕刻對二氧化錫初鍍膜卻有顯著影響，初鍍膜蝕刻後表面粗糙度提高並且霧度值亦提昇了。此外，不同工作壓力濺鍍之薄膜，其蝕刻效果也有所改變，初鍍膜蝕刻後之表面類似島狀起伏，降低濺鍍壓力可使島狀結構更加顯著，且其光散射效果更明顯，1*10-2torr濺鍍壓力的薄膜經蝕刻後可達最高霧度值約30%~50% (1000nm~350nm)。
另外，光微影製程輔助蝕刻，於玻璃基材上製備規則化圖案，再進行二氧化錫濺鍍，可以製備出具圖案表面之薄膜並且不影響薄膜本身電性。約10μm大小之規則化圖案可以提高薄膜之霧度值，2-D圖案對霧度的提昇效果較1-D圖案的效果更為顯著，具有10 μm矩形/2 μm間距之金字塔圖案之薄膜霧度約為22%。

Transparent Conductive Oxide (TCO) thin films, which show high conductivity and high transmittance in the visible wavelength range, have been used as the transparent electrode in solar cell devices. For application in solar cell, increasing surface roughness of transparent conductive oxide thin films is able to enhance light scattering at the rough surface and increase light path. This is so-called light trapping effect. Such an effect can increase the light absorption in solar cell and enhance the efficiency of solar cell.
TCO material used in this study was RF-magnetron-sputtered tin dioxide thin film. The surface of SnO2 film was treated by chemical etching method. The etching effect on surface morphology of SnO2 film before and after heat-treatment was investigated. The effect of different sputter pressure on the surface morphology and light scattering was also examined. In addition, a patterned structure was established on glass substrates using lithography method and then followed by sputtering SnO2 film. The light scattering of patterned substrates was also discussed.
The experimental results show the electrical and optical properties of SnO2 film increased after heat treatment, and the etched SnO2 film had different appearance. The etching effect is more pronounced on as-deposited film than the heat-treated film because of the densification on heat-treated film. Also, the structure of SnO2 film was influenced by different sputter pressure. The surface of SnO2 film after etching show island-like structure, and the island-like structure was more noticeable with decreasing sputter pressure, and it also enhance light scattering. SnO2 film at 1*10-2torr have the strongest light scattering with Haze value about 30% to 50% (1000nm~350nm).
In addition, the regular pattern on glass substrates using lithography method was prepared, and followed by sputtering of SnO2 film. So the SnO2 film with patterned surface can be prepared without sacrificing electrical property of SnO2 film. The results showed that the SnO2 film with micrometer size (about 10μm) pattern can increase the Haze value. The SnO2 film with 2-D pattern show better light trapping effect than that with 1-D pattern. The Haze value of SnO2 film with pyramidal pattern is about 22%.

參考文獻：
1. W. Beyer, J. Hüpkes, H. Stiebig, “Transparent conducting oxide films for thin film silicon photovoltaics”, Thin Solid Films, 516,p147-154,2007.
2. J. Krč, F. Smole, M. Topič, “Potential of Light Trapping in Microcrystalline Silicon Solar Cells With Textured Substrates”, Prog. Photovolt: Res. Appl., 11, p429-436, 2003.
3. F. Ruske, C. Jacobs, V. Sittinger, B. Szyszka, W. Werner, “Large area ZnO:Al film with tailored light scattering properties for photovoltaic applications”, Thin Solid Films, 515,p8695-8698,2007.
4. O. Kluth, B. Rech, L. Houben, S. Wieder, G. Schöpe, C. Beneking, H.Wagner, A. Löffl, H.W. Schock, “Texture etched ZnO:Al coated glass substrates for silicon based thin film solar cells”, Thin Solid Films, 351,p247-253,1999.
5. C. Haase, H. Stiebig, “Optical Properties of Thin-film Silicon Solar Cells with Grating Couplers”, Prog. Photovolt: Res. Appl., 14,p629-641,2006.
6. 楊明輝，“透明導電膜”，藝軒，p15，2006。
7. Brian Chpaman, “Glow Discharge Processes”, John Wiley and Sons, New York, 1980.
8. John A. Thornton, J. Vac.Sci. Technol., 11,p666,1974.
9. Oliver Kluth, Gunnar Schöpe, Jürgen Hüpkes, Chitra Agashe, Joachim Müller, Berned Rech, “Modified Thornton model for magnetron sputtered zinc oxide: film structure and etching behavior”, Thin Solid Films, 442, p80-85,2003.
10. Steven S. Hegedus, Ruhi Kaplan, “Analysis of Quantum Efficiency and Optical Enhancement in Amorphous Si p-i-n Solar Cells”, Prog. Photovolt: Res. Appl., 10,p257-269,2002.
11. J. Krč, M. Zmen, O kluth, F. Smole, M. Topič, “LIGHT SCATTERING PROPERIES OF SnO2 AND ZnO SURFACE-TEXTURED SUBSTRTES”, 3rd World Conference on Photovoltaic Energy Conversion, May11-18,2003,(Osaka,Japen).
12. Joachim Müller, Berned Rech, Jiri Springer, Milan Vanecek, “TCO and light trapping in silicon thin film solar cells”, Solar Energy, 77,p917-930,2004.
13. Mika Kambe, Makoto Fukawa, Naoki Taneda, Yukio Yshikawa, Kazuo Sato, Kazuki Ohki, Shuichi Hiza, Akira Yamada, Makoto Konagai, “IMPROVEMENT OF LIGHT-TRAPPING EFFECT ON MICROCRYSTALLINE SILICON SOLAR CELLS BY USING HIGH HAZE TRANSPARENT CONDUTIVE OXIDE FILMS”, 3rd World Conference on Photovoltaic Energy Conversion, May11-18,2003(Osaka,Japen).
14. H. Schade, Z E. Smith, “Mie scattering and rough surfaces”, Appl. Opt., 24,p3221-3226,1985.
15. 李冠卿，”近代光學”，聯經出版事業公司，p186-190,七十七年。
16. Donald A. Burns, Emil W. Ciurczak, “Handbook of Near-Infrared Analysis”, Marcel Dkker, Inc.,NewYork,p15,1992.
17. H. Schade, Z E. Smith, “Optical properties and quantum efficiency of a-Si1-xCx:H/a-Si:H solar cells”, J. Appl. Phys., 57,p568,1985.
18. H. P. Pillai, J. Krč, M. Zmen, “Optical Modeling of a-Si:H Thin Film Solar Cells with Rough Interfaces”, http://retina.et.tudelft.nl/data/artwork/publication/517711818.pdf .
19. L. Francioso, M. Russo, A.M. Taurino, P. Siciliano, “Micrometric patterning process of sol-gel SnO2,In2O3 and WO3 thin film for gas sensing applications: Towards silicon technology integration”, Sensors and actuators B,Chemical, 119,p159-166,2006.
20. J. Krč, M. Zmen, F. Smole, M. Topič, “Optical modeling of a-Si:H solar cells deposited on textured glass/SnO2 substrates”, J. Appl. Phys., 92,p749-755,2002.
21. 余樹楨,晶體之結構與性質,渤海堂,p281,1987.
22. I. Hamberg, C. G. Granqvist,“Band-gap widening in heavily Sn-doped In2O3”,Phys. Rev. B,30,p3240-3249,1984.