一种具有平顶陡边响应的长波长光探测器

A new long wavelength photodetector with flat-top and steep-edge spectral response

在PIN型光探测器的基础上制备了一种适用于波分复用系统的具有平顶陡边响应的长波长光探测器。利用低压金属有机化学气相沉积(LP-MOCVD)设备在GaAs衬底上二次外延生长了具有台阶结构的GaAs/AlGaAs滤波腔和InP基PIN光探测器。高质量的GaAs/InP异质外延采用了低温缓冲层生长工艺;具有台阶结构的Fabry-Pérot(F-P)滤波腔采用了纳米量级台阶的制备方法。通过理论计算优化了实现平顶陡边光谱响应特性的器件结构;并通过实验成功制备出了具有平顶陡边响应性能的光探测器,器件的工作波长位于1 549nm,峰值量子效率大于25%,0.5dB光谱响应线宽为3.9nm,3dB光谱响应线宽为4.2nm,响应速率达到17GHz。

A novel long-wavelength photodetector with flat-top steep-edge response has been fabricated,which can be used for wavelength division multiplexing（WDM） system.By using low pressure metal organic chemical vapor deposition（LP-MOCVD）,the step-shaped GaAs/AlGaAs distributed Bragg reflector（DBR） and the InP PIN photodetector are grown on GaAs substrate,and by employing a thin low-temperature buffer layer,the high quality GaAs/InP heteroepitaxy is realized.The structure of the photodetector is optimized by theoretical simulation.This device has good performance in the flat-top passband：the 0.5 dB bandwidth is 3.9 nm and the 3 dB bandwidth is 4.2 nm.The peak quantum efficiency of 25% around 1 549 nm and the 3 dB bandwidth of 17 GHz are simultaneously obtained.