【摘要】 高速850 nm GaAs/AlGaAs面入射型单行载流子光电探测器（PD）是短距离光链路中的重要器件，面临着带宽和响应度之间的相互矛盾。报道了一种基于分布布拉格反射器（DBR）增强的GaAs/AlGaAs单行载流子光电探测器（UTC-PD）。DBR由20个周期的高/低Al组分的Al_xGa_1-xAs三元合金组成，可以在830～870 nm范围内形成大于0.9的反射。在AlGaAs DBR的增强下，将GaAs吸收层所需的厚度降低到1 040 nm,兼顾PD对光的吸收率和光生载流子的渡越时间。采用双台面、聚合物平面化、共面波导电极结构制作了UTC-PD器件。该器件在850 nm波长、-2 V偏压下具有19.26 GHz的-3 dB带宽和0.492 6 A/W的响应度。更多还原

【Abstract】 GaAs/AlGaAs surface-illuminated uni-traveling carrier（UTC） photodiodes（PDs） are critical devices for short-range optical links. However, a conflict exists between bandwidth and responsiveness. We report a GaAs/AlGaAs UTC-PD enhanced by a distributed Bragg reflector（DBR） that consists of 20 cycles of high/low Al component Al_xGa_1-xAs and has a reflectance >0.9 in the wavelength range of 830～870 nm. The thickness of the GaAs absorption layer is reduced to 1 040 nm, which compromises the light absorption of the PD and transit time of photogenerated electrons. The UTC-PD device is fabricated with a double-mesas structure, polymer planarization, and a coplanar waveguide electrode. The device has a-3 dB bandwidth of 19.26 GHz, a responsivity of 0.492 6 A/W at a wavelength of 850 nm, and a bias of-2 V.更多还原