In the InP/InGaAs/InP PIN photodetector material growth, zinc is a normal doping ion and it has a high diffusion coefficient in InP and InGaAs. The Zn diffusion depth at the p-InP and intrinsic InGaAs boundary is critical for PIN photodiode high frequency characteristics. We control the p-InP Zn doping diffusion into intrinsic InGaAs layer by reducing the growth temperature of the p-type InP, decreasing the Zn doping concentration of the InGaAs/InP boundary, and increasing the growth rate of p-InP. We derive the exact voltage-controlled PIN photodiode capacitance expressions as a function of the Zn diffusion depth in the InGaAs intrinsic layer. This work reveals that the RC bandwidth of p-doping diffusion photodiode capacitance can be controlled by reverse voltage. And it gives a novel reference to design photodiode and varactor in optical microwave mixed circuits.

中文翻译：

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InP/InGaAs/InP光电二极管本征层Zn掺杂扩散控制与带宽调制


在InP/InGaAs/InP PIN光电探测器材料生长中，锌是一种普通的掺杂离子，在InP和InGaAs中具有较高的扩散系数。 p-InP 和本征 InGaAs 边界处的 Zn 扩散深度对于 PIN 光电二极管的高频特性至关重要。我们通过降低p型InP的生长温度、降低InGaAs/InP边界的Zn掺杂浓度以及提高p-InP的生长速率来控制p-InP Zn掺杂扩散到本征InGaAs层中。我们推导出精确的压控 PIN 光电二极管电容表达式，作为 InGaAs 本征层中 Zn 扩散深度的函数。这项工作揭示了 p 掺杂扩散光电二极管电容的 RC 带宽可以通过反向电压控制。为光微波混合电路中光电二极管和变容二极管的设计提供了新颖的参考。