发射极空气桥InGaP/GaAs HBT的DC和RF特性分析

Analysis of DC and RF Characterizations of InGaP/GaAs HBT with Emitter Air-Bridge Interconnection

为抑制电流增益崩塌,提高HBT的热稳定性,研制了发射极空气桥互连结构的HBT晶体管,应用ICCAP提取参数建立VBIC模型,结合模型参数对三种不同结构HBT的DC和RF特性进行比较分析.与引线爬坡互连结构相比,发射极空气桥互连结构HBT的热阻得到改善,热稳定性提高;与发射极电阻镇流方式相比,发射极空气桥HBT的截止频率(fT)相同,最大振荡频率(fmax)提高,最大稳定功率增益(MSG)高出约5dB.

In order to suppress current gain collapse and improve HBT＇s thermal stability, InGaP/GaAs HBT with novel emitter air-bridge interconnection was designed and fabricated, and its VBIC model was extracted using ICCAP. According to the model parameters, the characterizations of the HBT with different interconnection topologies were compared and analyzed. Contrast with typical climb interconnection HBT, its thermal resistance was reduced, therefore the thermal stability was improved. The cutoff frequency, fT, of the multi-finger HBT with emitter air-bridge interconnection was equal with that of multifinger HBT with climb interconnection and emitter ballasting resistor. But the maximum oscillation frequency, fmax, was higher, and the maximum stable gain, MSG, was 5 dB more than that of typical climb interconnection multi-finger HBT with emitter ballasting resistor.