硅基双极低噪声放大器的能量注入损伤与机理

Mechanism of Energy-Injection Damage of Silicon Bipolar Low-Noise Amplifiers

针对Si基双极型低噪声放大器(LNA),用脉冲调制150MHz射频信号在其输入端进行了能量注入实验,研究结果表明Si基LNA的噪声系数和增益特性都是注入能量的敏感参数.样品解剖和电路仿真显示能量作用使LNA内部晶体管出现基极/发射极金属化损伤,基极金-半接触电阻增大导致了LNA噪声系数增大,而Si基双极器件hFE随时间正向漂移损伤模式使LNA增益随注入能量的增加而增大.研究表明,由于能量作用下损伤效应的复杂性,以往可靠性研究中单纯采用增益的变化来衡量器件与电路的损伤效应的方法是不全面的.

Experiments of the energy injection into silicon bipolar low-noise amplifiers （LNA） are conducted by introducing pulsemodulated 150MHz radio frequency （RF） signal at LNAs inputs. The results show that the noise figure and the gain characteristic of silicon LNAs are sensitive to the injection energy. The metallization damage between the base and the emitter is correlated with the energy injection from the sample dissection analysis. The noise figure increases due to increased metal-semiconductor contact resistance of the base. The gain of the LNAs also increases with injection energy following the positive drift damage model of hvE for the silicon bipolar devices. Therefore, the traditional way to evaluate the damage effect of devices and circuits simply by the change of the gain is not comprehensive due to the complexity of the energy injection induced damage.