本研究探討的主題是在n-型矽晶圓上研製具有隔離氧化層的非晶碳化矽氫(a-SiC:H)、非晶氮化矽氫(a-SiN:H) 和電壓調色的非晶碳（氮）化矽氫[a-SiC(N):H]等n-i-p薄膜發光二極體，並量測及分析其光電特性。這些元件在n層及p層區域均分別採用組成摻雜梯度能隙(composition-dopant-graded gap)結構，以增加載子注入效率，提升元件的發光亮度、降低元件的操作電壓。在元件製程方面，利用在陰極附加不銹鋼濾網的電漿助長化學氣相沈積(PECVD)系統，以減少薄膜在沈積時遭電漿轟擊所造成的傷害，故可獲得品質較佳的非晶薄膜，並以最佳化退火製程，改善薄膜發光二極體的光電特性。所完成的非晶碳化矽氫(a-SiC:H) n-i-p 薄膜發光二極體的元件發光亮度在電流密度等於600 mA/cm2時為8100 cd/m2，發光臨限電壓值為19.1 V，電激發光(EL)頻譜峰值波長為600 nm，。而另一非晶氮化矽氫(a-SiN:H) n-i-p薄膜發光二極體的電激發光(EL)頻譜峰值波長為528 nm，發光臨限電壓值為15.4 V，，元件發光亮度在電流密度等於300 mA/cm2時為370 cd/m2。而電壓調色的非晶碳（氮）化矽氫[a-SiC(N):H] 薄膜發光二極體，在不同的偏壓下，電激發光(EL)頻譜峰值波長會在565 nm與670 nm間移動。

In order to investigate the feasibility of fabricating Si-based visible light-emitting diodes (LEDs) with common well-developed silicon processing technology, the SiO2-isolated n [phosphorous-doped hydrogenated amorphous silicon (n-a-Si:H) ] - i [intrinsic hydrogenated amorphous silicon-carbon (i-a-SiC:H) or intrinsic hydrogenated amorphous silicon-nitride (i-a-SiN:H)] - p [boron-doped hydrogenated amorphous silicon (p-a-Si:H)] thin-film LEDs (TFLEDs) were fabricated on n-type c-Si wafers. These SiO2-isolated TFLEDs would emit red-orange, green-white light and even light with voltage-tunable color.
The red-orange TFLED revealed a highest brightness of 8100 cd/m2 at an injection current density of 600 mA/cm2, an electroluminescence (EL) peak wavelength at 600 nm, and an EL threshold voltage = 19.1 V. The green-white TFLED had a brightness of 370 cd/m2 at an injection current density of 300 mA/cm2, an EL peak wavelength at 528 nm, and an EL threshold voltage = 15.4 V. The voltage-tunable TFLEDs had the EL peak wavelength ranged from 565 nm to 670 nm at different applied voltages.
The experimental results demonstrated the feasibility of developing Si-based visible light-emitting devices on c-Si substrate.

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