摘要
采用有机金属化学气相沉积法,在1μm氮化铝/蓝宝石衬底上制备了不同结构的AlGaN基多量子阱结构的深紫外发光二极管,其禁带边发光峰位为264 nm。使用透射扫描电镜对器件的结构进行了表征,测试了器件的光学和电学性能。通过分析电致发光谱得出:在器件活性区域和p型AlGaN盖层之间插入1 nm i-AlN电子阻挡层的样品其位于320 nm处的寄生发光峰能被有效抑制,该杂质峰主要是由于电子溢出至p型盖层,与处于Mg相关的受主深能级上的空穴复合所致。此外,验证了该电子阻挡层对发光特性具有一定的改善效果。通过优化UV-LED结构以及合理设定外延层的厚度参数,可以使其出光功率提高一个量级。
Using metal-organic chemical vapour deposition（ MOCVD）,the AlGaN-based multiple-quantum-well deep ultravoilet light-emitting diodes（ UV-LEDs） with different structures were successfully gown on 1 μm AlN /sapphire substrate. Its emssion peak position is 264 nm. Structural property was characterized by transmission electron microscopy,and the optical and electrical propertyies of the LEDs were measured. Comparing with elecctroluminescence spectra,in the sample with 1 nm i-AlN as a electron blocking layer（ EBL） between the active region and p-AlGaN cladding layers,the results show that a parasitic emission of 320 nm can be effectively suppressed. As a reason for its parasitic peak,electrons overflow into the p type cladding layer,then recombine with holes populating on the Mg related deep acceptor levels. In additon,it is demonstrated that the optical property can be improved using the EBL. The light output power of UV-LEDs can be enhanced with one order by the optimization the structure of the UV-LEDs and reasonable selection the thickness of the epilayer.
出处
《半导体技术》
CAS
CSCD
北大核心
2014年第10期743-746,共4页
Semiconductor Technology
基金
江苏省"六大人才高峰"高层次人才基金资助项目(2013-XCL-013)
南通大学引进人才科研启动基金资助项目(03080666)
