基于纳米硅结构的氮化硅基发光器件电致发光特性研究

Electroluminescence from Si nanostructure-based silicon nitride light-emitting devices

利用等离子体增强化学气相沉积法制备了镶嵌于氮化硅的高密度纳米硅薄膜,并以此作为发光有源层构建基于p-Si/氮化硅基发光层/AZO结构发光二极管,在室温下观察到了电致可见发光.在此基础上,在器件p-Si空穴注入层与氮化硅基发光层之间加入纳米硅薄层作为空穴阻挡层,研究器件电致发光性质,实验结果表明器件的发光强度显著增强,并且发光效率较无纳米硅阻挡层的发光器件提高了80%以上.

Dense Si nanostructures embedded in silicon nitride prepared by plasma-enhanced chemical vapor deposition （PECVD） was used as luminescence active layer to fabricate light-emitting diodes based on p-Si/SiN-based emitter/AZO structure. Visible electroluminescence from the device was observed at room temperature. It is found that the electrolu- minescence intensity of the device can be further enhanced significantly by inserting an ultrathin nanocrystalline Si layer between the p-Si substrate and SiN-based emitter as a hole barrier layer. Moreover, the electroluminescence efficiency is increased by more than 80% as compared to the decice without the nc-Si barrier layer.