用XPS研究~(60)Co对抗辐射加固和非加固Si-SiO_2的影响

对由抗辐射加固与非加固工艺生成的Si/SiO_2系统进行了~(60)Co辐照前后的界面结构分析。实验结果表明,这两类Si-SiO_2在硅的二氧化硅态和过渡态,氧的剩余氧态和负二价氧态的XPS谱上具有较大差异;其中非加固样品的XPS谱与辐照条件具有强烈的依赖关系,而加固样品的XPS谱随辐照条件的变化产生较小的变动。两类Si-SiO_2的XPS谱均显示出辐照剂量对样品的损伤作用大于辐照偏置电场。文中根据辐射在SiO_2-Si中产生电子-空穴对的观点,就实验现象进行了机制分析。

~(60)Co-Induced Structure Changes in Reinforced and Unreinforced Si-SiO_2

The interfacial structures of radiation-reinforced and unreinforced oxides grown by dry oxidation on n-type silicon substrates are examined using X-ray photoelectron spectroscopy (XPS) bef ore and af ter irradiation. Certain dif-ferences in silicon of SiO2(B. E. 103. 4 eV) state, silicon of transitional state (B. E. 101. 5 eV) ,surplus oxygen(B. E. 529. 6 eV) and negative two-valence oxygen(B. E. 531. 4 eV) are observed for the two kinds of Si-SiO2. The comparisons of XPS spectra indicate that the XPS spectra of radiation-unreinforced samples strongly depend on the conditions of irradiation while the XPS spectra of radiation reinforced samples change not so remarkable as unreinforced samples. The behaviors for both unreinforced and reinforced XPS show that the effect of irradiation dosage is greater than that of irradiation bias field. According to the theory of radiation-induced hole-electron pair,some viewpoints are put to the experimental results.