悬空车轮形氮化镓发光二极管

Floating GaN Micro Wheel Light Emitting Diodes

减少器件的界面损耗从而提升其发光性能一直是发光二极管领域一个重要的研究热点。本文采用标准半导体工艺在硅衬底上制备了GaN基车轮形发光器件。采用各向同性湿法蚀刻工艺将器件悬空,比较并研究了悬空对器件的性能,包括光强、半高宽、波长漂移、3 dB带宽等的影响。由于减小了光损耗,在悬空结构中腔效应更加明显,器件的电致发光和通信性能得到了提升。本研究对电驱动光源的制备和可见光通信具有重要意义。

Optical loss reducing and brightness improvement are always attractive issues for light emitting diodes.In this paper,GaN based micro wheel light emitting devices(LED)are fabricated on silicon substrate by standard semiconductor technology.Isotropic wet etching process is applied to suspend the device thus optimize the device performance.Electroluminescence(EL)characteristics including the spectral intensity,full width at half maximum(FWHM),turn-on voltage and current induced wavelength shift,communication characteristics such as 3 dB bandwidth of two GaN micro wheels are studied and compared.Due to the reducing of optical loss,cavity effect is more obvious in the floating structure,and the improved EL and communication performance are obtained.The research in this paper is of great significance for the preparation of the electrically pumped light source and the visible light communication.