在本文中，我們使用液相氧化法應用在磷化銦鎵/砷化鎵異質接面雙極性電晶體(InGaP/GaAs HBT)上。在此氧化法操作使用上相較於其他系統氧化法較為簡單且容易。並能在低溫環境(30℃~70℃)下操作無需外加其他能量輔助來成長出較均勻的氧化層。此外，在氧化層方面，我們也利用掃描式電子顯微鏡(SEM)和原子力顯微鏡(AFM)的分析來探討氧化層表面的變化。且利用不同特性的氧化層在異質接面雙極性電晶體上做鈍化層的研究及其探討直流特性。利用液相氧化法在表面做鈍化的應用，可以明顯地得到直流增益的增加，這表示在基極-射極表面能夠充份的抑制電流的復合，降低基極電流。在直流特性分析方面，在電流增益和崩潰電壓方面比未鈍化的結構有些許的改善。在基極-集極介面的崩潰電壓方面，鈍化處理的崩潰電壓都有明顯的改善。最大崩潰電壓在於表面氧化處理15分鐘的元件(23.8伏特)。在低集極電流部份，利用表面鈍化處理後得到最小的集極電流(7.5x10-11安培)。而且在此低集極區域，經過鈍化處理的電晶體比起未鈍化處的電晶體有數倍增益的差異。

InGaP/GaAs heterojunction bipolar transistors (HBTs) passivated with liquid phase oxidized layers is probed. Compare with other oxidation systems, liquid phase oxidization (LPO) method to grow the uniform oxide is simple and easy without extra energy in low temperature environment (from 30°C to 70°C). The oxidized layers are first characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Then, the oxide layers are then applied to the InGaP/GaAs HBTs. As results show, the DC current gain increases significantly by using the LPO method passivated on the InGaP/GaAs surface. It could prove the evidence that the passivation could sufficiently suppress the recombination current and then reduce the base current. In addition, the breakdown voltage can be also improved dramatically. The breakdown voltage for the device with surface oxidized 15 minutes can be increased up to 23.8 V. The lowest collector current was available in surface treatment (up to 7.5*10-11A). And the current gain would have several folds enhancement for the device with oxide treatment than that without treatment.

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