离子束引起的在Al/Cr双层薄膜界面处的原子混合

ION BEAM INDUCED ATOMIC MIXING IN Al/Cr BILAYERED SAMPLES'

用600keV的Kr^+离子轰击Al/Cr双层薄膜样品进行界面原子反应及相互混合的研究。实验样品是在单晶硅上蒸镀约500nm厚的铝膜,相继再蒸上所需厚度的铬膜而制成的。轰击剂量为2.0×10^(15)-2.5×10^(16)Kr^+/cm^2。用2.0MeVa粒子对轰击前后的样品进行了卢瑟福背散射(RBS)分析,发现界面处有明显的原子混合存在;当轰击剂量≥1.0×10^(16)Kr^+/cm^2时,RBS谱出现有明显的坪台,经拟合计算和x射线衍射(XRD)测量证实确有化合物Al_(13)Cr_2存在;还分别得到了原子混合量及混合效率与轰击剂量的关系;最后对界面处的原子混合机制进行了讨论。

Interfacial atomic mixing of Al/Cr bilayered samples bombarded by 600 keV Kr+ ions has been investigated. The samples were prepared by sequential evaporation of about 500nm of Aluminium followed by various desirable thickness of chromium onto a single-crystal silicon. The irradiation was performed with fluences from 2.0×l015Kr+/cm2 at room temperature. All samples have been analyzed by RBS using a 2 MeV 4He beam. The RBS Spectra show that the interfacial atomic mixing is observed apparently. When the bombarded fluence io larger than 1.0×10t6Kr+/cm2, the RBS spectra exhibit the steps at the low energy edge of Cr spectrum and the high energy edge of Al. By theoretical fitting it indicates that the compound Alt3Cr2 was formed at the interface and x-ray diffraction also demonstrated it. Finally the mechanism of interfacial atomic mixing was simply discussed.