双极晶体管微波损伤效应与机理

结合Si基n⁺-p-n-n⁺外延平面双极晶体管, 考虑了器件自热、高电场下的载流子迁移率退化和载流子雪崩产生效应, 建立了其在高功率微波(high power microwave, HPM)作用下的二维电热模型. 通过分析器件内部电场强度、电流密度和温度分布随信号作用时间的变化, 研究了频率为1 GHz的等效电压信号由基极和集电极注入时双极晶体管的损伤效应和机理. 结果表明集电极注入时器件升温发生在信号的负半周, 在正半周时器件峰值温度略有下降, 与集电极注入相比基极注入更容易使器件毁伤, 其易损部位是B-E结. 对初相分别为0和π的两个高幅值信号的损伤研究结果表明, 初相为π的信号更容易损伤器件, 而发射极串联电阻可以有效的提高器件的抗微波损伤能力.

The damage effect and mechanism of the bipolar transistor caused by microwaves

Combining self-heating effect, mobility degradation in high electric field and avalanche generation effect, a two-dimensional electro-thermal model of the typical silicon-based n⁺-p-n-n⁺ structure bipolar transistor induced by high power microwave is established in this paper. By analyzing the variations of device internal distributions of the electric field, the current density and the temperature with time, a detailed investigation of the damage effect and the mechanism of the bipolar transistor under the injection of 1GHz equivalent voltage signals from the base and collector is performed. The results show that temperature elevation occurs in the negative half-period and the maximum temperature falls slightly in the positive half-period when the signals are injected from the collector. Compared with the former, device damage occurs easily with the signals injected from the base. Specifically, the base-emitter junction is susceptible to damage. The damage results caused by two large-amplitude signals with initial phases of 0 and \uppi respectively indicate that the injected signal with an initial phase of \uppi is liable to cause device damage. Meanwhile, the emitter series resistance can enhance the capability of the device to withstand microwave damage effectively.