设计并生长了一种新的InGaP/GaAs/InGaPDHBT结构材料,采用在基区和集电区之间插入n^+-InGaP插入层结构,以解决InGaP/GaAs/InGaPDHBT集电结导带尖峰的电子阻挡效应问题。采用气态源分子束外延(GSMBE)技术,通过优化生长条件,获得了高质量外延材料,成功地生长出带有n^+-InGaP插入层结构的GaAs基InGaP/GaAs/InGaPDHBT结构材料。采用常规的湿法腐蚀工艺,研制出发射极面积为100μm×100μm的新型结构InGaP/GaAs/InGaPDHBT器件。直流特性测试的结果表明,所设计的集电结带有n^+-InGaP插入层的InGaP/GaAs/InGaPDHBT器件开启电压约为0.15V,反向击穿电压达到16V,与传统的单异质结InGaP/GaAsHBT相比,反向击穿电压提高了一倍,能够满足低损耗、较高功率器件与电路制作的要求。
A new InGaP/GaAs/InGaP DHBT structure has been designed and grown in this work. An n^+-InGaP layer at base/collector interface was inserted between collector and base to eliminate the carrier blocking effect. The InGaP/GaAs/InGaP DHBT structures were grown by gas source molecular beam (GSMBE). A good crystalline quality of GaAs, InGaP,and InGaAs materials was obtained through optimizing the growth conditions. The InGaP/GaAs/InGaP DHBT structures were also grown successfully. The InGaP/GaAs/InGaP DHBT device with emitter area of 100μ m× 100 μm was fabricated by wet mesa etching process. The offset voltage of the InGaP/GaAs/InGaP DHBT is 0. 15 V, and the breakdown voltage as high as 16 V was obtained. It means that the breakdown voltage of the DHBT designed in this work is one times higher than that of the single heterojunction HBTs. These results indicate that the InGaP/GaAs/ InGaP DHBT is suitable for low power-dissipation and high power applications.