砷化镓表面P＿2S＿5／NH＿4OH钝化研究

STUDIES ONN PASSIVATING A P_2S_5/NH_4oH-TREATED GaAs SURFACE ZONG XIANGFU WENG YUMIN LID KEIFENG

用Ｘ光电子能谱（ＸＰＳ）、先致发光（ＰＬ）和俄歇电子能量谱（ＡＥＳ）研究Ｐ＿２Ｓ＿５／ＮＨ＿４ＯＨ对ｎ型ＧａＡｓ（１００）晶面的钝化作用．测试结果表明，钝化后在砷化镓（１００）面上的自然氧化物已被除去，表面形成了一层性质稳定的硫原子层．硫原子与砷、镓原子分别有效地成键，阻止了砷化镓表面氧化物的组成，并消除了表面存在的悬挂键，从而大大优化了ＧａＡｓ（１００）面的特性．ＰＬ实验结果支持了上述结论．实验结果表明钝化后ＧａＡｓ表面复合速度下降，表面态密度降低．

The effect of P_2S_5/NH_4OH treatment on the (100)surface of GaAs was studiedby X-ray photoelectron spectroscopy(XPS),Auger electron spectroscopy(AES)and photoluminescence(PL).The results show that after passivation the nativeoxide of GaAs Surface is completely removed and a passivation layer mainlycomposed of As-Sand Ga-Sbonds forms on the sample surface,and prevents theadsorption of oxygen. This concluson has been supported by results of PLexperiments.The PL intensity and its contrast obtained on GaAs surface dependon the surface recombination and they are controlled by passivation. The results of PL experiments show the reduction of surface recombination and of the densityof surface states P_2S_5/NH_4OH treatment is more stable than the others,such as Na_2S.