表面增透结构AlGaInP LED的研究

A kind of AlGaInP light emitting diode （LED） with surface anti-reflecting structure has been introduced to solve the problems of low light efficiency and restricted luminous intensity. The new structure can be demonstrated theoretically and experimentally, and LEDs with the new structure have higher on-axis luminous intensity and larger saturation current than conventional LEDs and LEDs with ITO film only, which is caused by higher external quantum efficiency and also higher internal quantum efficiency. The new LEDs are especially suitable for working at large injected currents.     

发光二极管表面结构对出光特性的影响

用传输矩阵法模拟计算了AlGaInP发光二极管(LED)不同表面结构的光学特性,用等离子体增强化学气相沉积(PECVD)或磁控溅射掺铟氧化锡(ITO)设备,在带有DBR结构的外延衬底上制备出具有不同表面层结构的LED.通过实验结果对比表明,表面生长λ/4n SiON加λ2n ITO增透膜结构复合增透膜的LED,器件光学性能提高最佳,在20 mA注入电流下,光强和光通量分别达到141.7 mcd和0.4733 lm.比同样结构的无增透膜LED轴向光强和光通量分别提高138%和91%.     

980nm半导体激光器远场特性的优化

制作小功率半导体激光器时,为了减小阈值电流,提高斜率效率,一般都采用深腐蚀法形成脊形结构以克服电流横向扩展.但是由于工艺的原因,往往使得激光器远场特性恶化,特别是水平发散角θ//形成多瓣.研究发现这与光刻工艺有着重要关系,并利用自对准自然解理边形成TiAu欧姆接触方法克服了此现象,改善了远场特性.