本研究利用三種具有不同官能基的矽烷(DDTS, PTES和APMDS)來修飾ITO玻璃的表面，並探討經不同矽烷修飾過的ITO電極與電洞傳輸層(NPB)間的界面形態以及其對OLED元件特性的影響。研究結果發現，利用不同官能基的矽烷來修飾ITO表面，不但會改變ITO基板的表面能，還會影響電洞從陽極注入的情況。因為受到基板表面能所影響，NPB在不同矽烷改質之ITO表面的潤濕性大小依序為ITO > ITO/PTES > ITO/APMDS > ITO/DDTS。而NPB在不同基板上的熱穩定性依序為：ITO > PTES > APMDS > DDTS。然而，基板的表面能似乎對OLED元件的特性影響不大。OLED元件的特性主要受到矽烷尾端的不同官能基的推拉電子特性所影響。因此，經矽烷修飾過的OLED 元件其起始電壓為ITO/PTES < ITO/DDTS < ITO < ITO/APMDS，顯示出PTES有助於電洞的注入，而APMDS則可以阻擋電洞的傳輸。在PTES元件中，因電洞數目增加使得電子/電洞結合數目增多，故元件有較大的電流密度及發光強度。然而，因電子注入的數目沒有因PTES的修飾而增加，故與電洞的結合機率反而下降，故其發光效率低於未經修飾的元件。相對的，因APMDS有效抑制電洞的注入，促使電子電洞的數目較為接近，雖然電子/電洞結合數目因此下降，其結合之機率則提高了，故APMDS元件的發光效率較未修飾之ITO元件大。

　In this work, three simple silanes including dodecyl-trichlorosilane (DDTS), phenyl-triethoxy-silane (PTES), and 3-aminopropyl-methyl-di-ethoxysilane (APMDS) were used to modify the ITO surfaces. The effects of various terminal groups of silanes on the growth behavior and interfacial morphologies of NPB film deposited on the SAM modified ITO were studied, as well as their effects on the OLED device performance. Using different terminal function group of silanes to modify the ITO surface, not only will affect the surface energy of substrates surface, but also will influence the holes injection from anode in OLED devices. Because of the different surface energy, the wettabiliy of NPB on the SAM modified substrates decreases in the order: bare ITO > ITO/PTES > ITO/APMDS > ITO/DDTS, and the thermal stability of NPB films on these substrates are found to decrease in the order: bare ITO > PTES > APMDS > DDTS. However, the surface energy seems not to affect the characteristics of OLED devices, but to be influenced by the original property of terminal function group of substrates. The turn on voltage for these devices increases in the order: ITO/PTES < ITO/DDTS < bare ITO < ITO/APMDS. The luminescence efficiency is in the order: ITO/PTES < ITO/DDTS < bare ITO < ITO/APMDS.

Aziz, H.; Popovic, Z. D.; Hu, N.-X.; Hor, A.-M., and Xu, G., “Degradation mechanism of small molecule-based organic light-emitting devices”, Science, 283, 1900, 1999.

Bard, A. J., and Faulkner, L. R., “Electrochemical methods: fundamentals and applications”, John Wiley and Sons, Inc., USA, p.231, 2001.

Brandriss, S., and Margel, S., “Synthesis and characterization of self-assembled hydrophobic monolayer coatings on silica colloids”, Langmuir, 9, 1232, 1993.

Brozoska, J. B.; Azouz, I. B., and Rondelez, F., “Silanization of solid substrates: a step toward reproducibility”, Langmuir, 10, 4367, 1994.

Burroughes, J. H.; Bradley, D. D. C.; Brown, A. R.; Marks, R. N.; Mackay, K.; Friend, R. H.; Burns, P. L., and Holmes, A. B., “Light-Emitting Diodes Based on Conjugated Polymers” Nature, 347, 539, 1990.

Carrard, M.; Goncalves-Conto, S.; Si-Ahmed, L.; Adès, D., and Siove, A., “Improved stability of interfaces in organic light emitting diodes with high Tg materials and self-assembled monolayers”, Thin Solid Films, 352,189, 1999.

Cui, J.; Huang, Q.; Veinot, J. G. C.; Yan, H., and Marks, T. J., “Interfacial microstructure function in organic light-emitting diodes: Assembled tetraaryldiamine and copper phthalocyanine interlayers”, Adv. Mater., 14, 565, 2002.

Grange, J. D. L.; Markham, J. L., and Kurkjian, C. R., “Effects of surface hydration on the deposition of silane monolayers on silica”, Langmuir, 9, 1749, 1993.

Hashimoto, Y.; Osato, Y.; Tanaka, M.; Hamagaki M., and Sakakibara, T., “Effect of oxygen plasma treatment of indium tin oxide for organic light-emitting devices with iodogallium phthalocyanine layer”, Jpn. J. Appl. Phys., 41, 2249, 2002.

http://micro.magnet.fsu.edu/primer/java/jablonski/jabintro/index.html.

Hung, L. S.; Tang, C. W., and Mason, M. G., “Enhanced electron injection in organic electroluminescence devices using an Al/LiF electrode”, Appl. Phys. Lett., 70, 152, 1997.

Jabbour G. E.; Kawabe, Y.; Shaheen, S. E.; Wang, J. F.; Morrell, M. M.; Kippelen, B., and Peyghambarian, N., “Highly efficient and bright organic electroluminescent devices with an aluminum cathode”, Appl. Phys. Lett., 71, 1762, 1997.

Kalinowski, J., “Electroluminescence in orgaincs“, J. Phys. D: Appl. Phys. 32, R179, 1999.

Lee, J.; Jung, B.-J.; Lee, J.-I.; Chu, H. Y.; Do, L.-M., and Shim, H.-K., “Modification of and ITO anode with a hole-transporting SAM for improved OLED device characteristics”, J. Mater. Chem., 12, 3494, 2002.

Lee, K. H.; Jang, H. W.; Kim, K.-B.; Tak, Y.-H., and Lee, J.-L., “Mechanism for the increase of indium-tin-oxide work function by O2 inductively coupled plasma treatment“, J. Appl. Phys., 95, 586, 2004.

Malinsky, J. E.; Jabbour, G. E.; Shaheen, S. E.; Anderson, J. D.; Richter, A. G.; Marks, T. J.; Armstrong, N. R.; Kippelen, B.; Dutta, P., and Peyghambarian, N., “Self-assembly processes for organic LED electrode passivation and charge injection balance”, Adv. Mater., 11, 227, 1999.

McGovern, M. E.; Kallury, K. M. R. and Thompson, M., “Role of solvent on the silanization of glass with octadecyltrichlorosilane”, Langmuir, 10, 3607, 1994.

Mitschke, U., and Bäuerle, P., “The electroluminescence of organic materials“, J. Mater. Chem., 10, 1471, 2000.

Nalwa, H. S., and Rohwer, L. S., “Handbook of Luminescence, Display Materials, and Devices”, American Scientific Publishers, 2003.

Nüesch, F.; Rothberg, L. J.; Forsythe, E. W.; Le, Q. T., and Gao, Y., “A photoelectron spectroscopy study on the indium tin oxide treatment by acids and bases”, Appl. Phys. Lett., 74, 880, 1999.

Parikh, A. N.; Allara, D. L.; Azouz, I. B., and Rondelez, F. J., “An intrinsic relationship between molecular structure in self-assembled n-alkylsiloxane monolayers and deposition temperature”, J. Phys. Chem., 98, 7577, 1994.

Rye, R. R., “Transition temperatures for n-alkyltrichlorosilane monolayers”, Langmuir, 13, 2588, 1997.

Shipway, A. N.; Lahav, M., and Willner, I., “Nanostructured gold colloid electrodes”, Adv. Mater., 12, 993, 2000.

Silberzan, P.; Lèger, L.; Ausserrè, D., and Benattar, J. J., “Silanation of silica surfaces. A new method of construction pure or mixed monolayers”, Langmuir, 7, 1647, 1991.

Streetman, B. G., and Banerjee, S., “Solid State Electronic Devives”, Prentice Hall, Inc., 2000.

Subramaninan, V.; Wolf, E., and Kamat, P. V., “Semiconductor-metal composite nanostructures. To what extent do metal nanoparticles improve the photocatalytic activity of TiO2 films? ”, J. Phys. Chem. B, 105, 11439, 2001.

Tang, C. W., and VanSlyke, S. A., “Organic electroluminescent diodes”, Appl. Phys. Lett., 51, 913, 1987.

Tang, H.; Li, F., and Shinar, J., “Bright high efficiency blue organic light-emitting diodes with Al2O3/Al cathodes”, Appl. Phys. Lett., 71, 2560, 1997.

Turak, A.; Grozea, D.; Feng, X. D.; Lu, Z. H.; Aziz, H., and Hor, A. M., “Metal/AlQ3 interface structures”, Appl. Phys. Lett., 81, 766, 2002.

Ulman, A., “Formation and structure of self-assmebled monolayers”, Chem. Rev., 96, 1533, 1996.