深能级对AlGaInP/GaAs异质结双极晶体管性能的影响

INFLUENCE OF DEEP LEVELS ON THE PERFORMANCE OF AlGaInP/GaAs HETEROJUNCTION BIPOLAR TRANSISTOR 

用深能级瞬态光谱和光致发光（ＰＬ）方法研究了ＡｌＧａＩｎＰ／ＧａＡｓ异质结双极晶体管（ＨＢＴ）发射区ＡｌＧａＩｎＰ中的深能级．得到了两个深能级，分别为Ｅｃ－Ｅｔ１＝０４２ｅＶ和Ｅｃ－Ｅｔ２＝０５９ｅＶ，其复合截面为σｎ１＝６２７×１０－１７ｃｍ２和σｎ２＝６４９×１０－２０ｃｍ２．这两个深能级分别与硅杂质和氧杂质相联系．从不同激发功率与ＰＬ峰强度的关系，说明在ＡｌＧａＩｎＰ中存在深能级非复合中心．ＡｌＧａＩｎＰ／ＧａＡｓＨＢＴ发射区ＡｌＧａＩｎＰ中深能级的存在使器件的电流增益减小．

Abstract We have studied deep levels in AlGaInP emitter of AlGaInP/GaAs heterojunction bipolar transistor by deep level transient spectroscopy and photoluminescence (PL) methods.Two deep levels were obtained with thermal activation energies of E c- E t1 =0 42eV and E c- E t2 =0 59eV,whose capture cross sections are 6 27×10 -17 cm 2 and 6 49×10 -20 cm 2,where E t1 and E t2 are Si related and O related deep levels,respectively. The relationship between excitation power and PL peak intensity have revealed that nonradiative recombination centers of deep levels exist in AlGaInP. The current gain of AlGaInP/GaAs HBT decreases due to the existence of deep levels in AlGaInP.