单载流子传输光敏晶体管小信号等效电路模型的建立与分析  

Modelingand Analysis of a Uni-traveling Carrier Phototransistor Based on its Small Signal Equivalent Circuit

作　　者：孙丹 谢红云 刘芮 刘硕 吴佳辉 张万荣 

机构地区：[1]北京工业大学信息学部电子科学与技术学院,北京100124

出　　处：《光子学报》2017年第11期49-55,共7页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.61604106;61574010;61006044;61774012);北京市未来芯片技术高精尖创新中心科研基金(No.KYJJ2016008);北京市自然科学基金(Nos.4122014;4142007);山东省自然科学基金(No.ZR2014FL025)资助~~

摘　　要：建立了单载流子传输双异质结光敏晶体管的小信号等效电路模型.分析了单载流子传输双异质结光敏晶体管光生电流的产生机制,并将其作为基极电流的一部分,引入到小信号等效电路中.分析了单载流子传输双异质结光敏晶体管中单载流子传输的输运方式对光跨导、发射结电阻、发射结结电容和集电结结电容的影响.基于所建模型,研究了InP基单载流子传输双异质结光敏晶体管的光特征频率和光电流增益受光窗口面积和入射光功率的影响.结果表明,在同样入射光功率下,存在一个最佳的光窗口面积使得光特征频率获得最大值,最佳光窗口面积随入射光功率的增加在一定面积范围内发生偏移.在固定光窗口面积(8×8μm2)条件下,随着输入光功率的增加,光特征频率先增大后减小,在280μW时达到最高值150GHz,光短路电流增益也随着光功率的增加而逐渐增加,在入射光功率750μW时达到饱和,饱和增益为82dB.The small signal equivalent model of a Uni-Traveling Carrier Double Hetero-junction Phototransistor （UTC-DHPT） was established. In this model, the optical generated current in UTC-HPT was introduced reasonably as part of base current. The influence of single carrier transportation in UTC-DHPT on photo transconductance, emitter junction effective resistor, emitter junction capacitor, and collector junction capacitor were analyzed. Based on the established small signal equivalent model, the dependence of optical characteristic frequency and the optical generated current gain on optical window area and illumination light power of an InP-based UTC-DHPT were analyzed. At certain illumination light power, there is an optimum window area which can achieve the maximum optical characteristic frequency. Meanwhile, the optimum window area would change in certain range as illumination light power increasing. When chosen the optical injection window of 8×8 μm^2 , With the gradual increase of illumination light power, the characteristic frequency increases at first and then decreases, the highest value reaches 150 GHz at 280 μW. The gain of optical generated current increases gradually too and reaches the saturation gain of 82 dB under 750 μW.

关 键 词：小信号等效电路模型 单载流子传输 光敏晶体管 光特征频率 光短路电流增益 

分 类 号：TN2[电子电信—物理电子学]