光探测器TO封装的高频分析与改进

推导了封装前后探测器的散射参数的关系,提出了探测器封装网络高频影响的两种分析方法.一种方法是直接比较封装前后探测器的频响,另一种则是从待封装探测器的反射系数和封装网络散射参数计算获得.以TO封装探测器为例,对两种方法的有效性进行了验证.分析结果表明,封装网络中电容和电感的谐振效应具有补偿作用,通过改变封装中的这些参数,改进了TO封装探测器的频响.

Analysis and Improvement on the High Frequency Effect of TO Packaging for Photodiodes

Two methods for analyzing the high frequency effect of the packaging techniques for photodiodes are presented.The first method compares the frequency responses of the photodiode before and after packaging,and the second one is based on the relations between the scattering parameters of the packaging network,photodiode chip,and module.In the experiment of the TO photodiode module,results from the two methods show coherence,which indicates that the methods established are effective for practical applications.Analysis results also denote that there is a resonance between the inductance in the bonding wire and the parasitic capacitance in both the feedthru of the TO header and the photodiode chip.This resonance can be used to compensate for the overall frequency response of the device.By adjusting the values of the inductance and capacitance,an optimized frequency response of the TO photodiode module is achieved.