太赫兹肖特基二极管噪声电压的理论研究

Theoretical Investigation of Terahertz Schottky-Barrier Diode Noise Voltage

在太赫兹焦平面成像等系统中,Ga As肖特基二极管作为太赫兹检测的核心器件,其噪声特性直接影响太赫兹探测系统的灵敏度。讨论了Ga As肖特基二极管在不同直流偏压下加载给负载的热噪声电压、散粒噪声电压、总噪声电压,并给出了相应的解析解。同时,建模模拟了太赫兹混频前端,并利用谐波平衡法对理论公式进行了对比验证。对太赫兹像元与阵列芯片的噪声机理以及提高芯片的噪声性能研究,改善芯片噪声特性,从而提高太赫兹焦平面成像系统灵敏度具有重要意义和作用。

In terahertz imaging focal plane system,as the key device of THz detection devices,Ga As Schottky diode directly affects the noise sensitivity of the THz detecting system. In this paper,we discussed thermal noise,shot noise and the total noise voltage of Ga As Schottky diodes under different DC bias,and gave the small signal analytical solutions. At the same time,a THz mixer model was created to verify the analytical solutions. The paper is significant to study the noise mechanism of terahertz pixels and array in chip and improve the noise performance of the chip,thereby improving the sensitivity of the terahertz imaging focal plane system.