摘要
本論文研究低介電常數材料Hydrogen silsesquioxane (HSQ)於薄膜電晶體技術上的應用。由於低介電常數材料(HSQ)應用於薄膜電晶體(TFT)元件上的平化保護層(planarized passivation layer)時，除了其具有高透光率(>90% at300-800nm)、低的光漏電以及好的平坦化(planarization)能力之外，還能夠提高薄膜電晶體顯示器的開口率(aperture ratio)，降低電晶體陣列連線中電阻-電容延遲時間(RC delay time)。因此，低介電常數材料於薄膜電晶體顯示器上的研究與應用，便成為重要的顯示器技術發展趨勢。本論文選擇一種具有潛力的低介電常數材料，Hydrogen silsesquioxane (HSQ)做為研究主題。
在對薄膜電晶體上的應用，溫度是製程中最重要的因素。我們在本論文中分別探討了350, 330以及300度的製程後的元件特性。
研究的總結，我們發現由於HSQ的高透光率、極低的可見光敏感性，因此，在長期照光操作下對元件並不會產生太大的影響。另外元件也可能因HSQ中的Si-H將懸鍵修補，使得元件特性在300度HSQ保護下有所提昇。所以，未來HSQ薄膜將是最有可能替換傳統氮化矽保護層，成為應用在薄膜電晶體保護層方面的候選人。

Abstract

In this thesis, we investigated the application of low-dielectric-constant (low-k) hydrogen silsesquioxane (HSQ) for thin-film-transistor (TFT) technology. Low-k HSQ has the properties of the high transmittance (>90% at 300~800 nm), low photo leakage current and good planarization for TFT passivation layer. In addition, it can effectively increase the aperture ratio of display matrix and reduce resistance-capacitance delay (RC delay). Therefore, the application of the low-k materials on TFT device has become one of the most important issue for flat panel display. In this study we have investigated one of the promising candidates of low-k dielectrics, hydrogen silsesquioxane (HSQ), for TFT array technology application.
In TFT process, temperature is the most important issue. In this study, the characteristics of devices after different process temperature, 350, 330 and 300℃, are discussed.
In conclusion, we have found that HSQ film has high illumination, low photo leakage current; thereby, the leakage of devices is little changed by illumination. Otherwise, the Si-H bonds of HSQ may passivated the dangling bonds on the channel surface and the characteristic of device for HSQ 300℃ passivation is improved. This indicates that HSQ is the most possible candidate to replace the conventional SiNx passivation layer on TFT device in the future.

References
[1] T. E. Seidel and C. H. Ting, “Methods and Needs For Low k Material Research,” Mater. Res. Soc. Symp. Proc. 381, 3 (1995).
[2] R. Y. Leung, T. Nakano, S. Case, B. Sung, J. J. Yang, and D. K. Choi, Int. Dielectrics for ULSI Multilevel Interconnection Conference, p. 49 (1997).
[3] G. Sugahara, N. Aoi, M. Kubo, K. Arai, and K. Sawada, “Low Dielectric Constant Carbon Containing SiO2 Films Deposited by PECVD Technique Using a Novel CVD Precursor,” Int. Dielectrics for ULSI Multilevel Interconnection Conference, p. 19 (1997).
[4] V. McGayay, A. Acovic, B. Argarwala, G. Endicott, M. Shapiro, and S. Yankee, Int. VLSI Multilevel Interconnection Conf. Proc., p. 116 (1996).
[5] M. J. Loboda, C. M. Grove and R. F. Schneider, “Properties of a-SiOx:H Thin Films Deposited from Hydrogen Silsesquioxane Resins,” J. Electrochem. Soc., 145, 2861 (1998).
[6] H. Meynen, R. Uttecht, T. Gao, M. Van Hove, S. Vanhaelemeersch and K. Maex, in the Electrochem. Soc. Proceedings of the 3rd international Symposium on Low and High Dielectric Constant Materials, 98-3, 29 (1998).
[7] D. Thomas, and G. Smith, Dielectrics for ULSI Multilevel Interconnection Conf., p. 361 (1997).
[8] B. T. Ahlburn, G. A. Brown, T. R. Seha, and T. F. Zoes, Int. Dielectrics for ULSI Multilevel Interconnection Conference, p. 36 (1995).
[9] N. H. Hendricks, “Low Dielectric Constant Materials for IC Intermetal Dielectric Applications: A Status Report on the Leading Candidates,” Mater. Res. Soc. Symp.Proc., 443, 3 (1996).
[10] J. N. Bremmer, Y. Liu, K. G. Gruszynski, and F. C. Dall, Int. Dielectrics for ULSI Multilevel Interconnection Conference, p. 333 (1997).