本研究的主要目的是研製交流非晶質薄膜發光二極體。在現階段，我們成功地運用一層很薄的本質非晶碳化矽氫做為發光層，且利用PECVD系統將ITO透明電極表面做氧電漿處理，提高ITO透明電極功函數並降低與本質非晶碳化矽氫之間的蕭特基位障。實驗結果顯示，適當的氧電漿處理確實能夠有效改善接觸電阻，大幅提升元件發光效率；若更進一步加以退火處理，使ITO透明電極再結晶而降低其片電阻值，則元件會有更佳的可靠度。同時我們也對元件做一系列電性量測，包括發光亮度、發光頻譜以及交流頻率響應等。量測結果顯示，不同大小的電壓及頻率幾乎不會改變發光波段，而且我們也發現當薄膜發光二極體操作在特定頻率範圍時，可有效提昇元件發光亮度。 The a-SiC:H thin-film light-emitting diodes (TFLED) which could be operated under the alternating current (AC) power supply have been designed and fabricated in this study. So far, the intrinsic a-SiC:H layer has been successfully used as the radiative layer and the effects of treating indium-tin-oxide (ITO) electrode surface with O2-plasma on the TFLED performance has been investigated. The O2-plasma treatment of ITO electrode resulted in an increase of its work function, and the brightness of a plasma-treated device has been significantly increased at the same injected current. In addition, it has been found that sheet resistance of the ITO films after annealing was decreased, and the reliability of device could be improved obviously. The frequency response of the obtained devices has been studied too. The peak wavelength of electroluminescence (EL) spectrum was almost independent of applied-voltage amplitude and frequency, and a higher EL intensity of the device was observed when the device was operated under a particular frequency range. The role of the AC frequency for the EL intensity was discussed also.
