InP清洁表面上电子感应吸附氧的研究

用俄歇电子能谱观察清洁InP表面在电子束照射下与真空室中H₂O和O₂的相互作用,发现水蒸汽所引起的电子束感应吸附氧的作用比氧气要明显得多。在吸附氧的同时,In和P的俄歇信号也发生变化,分析其过程为一种氧化过程,氧一开始先同表面的In结合成为氧化铟,随后向表面以内透入,并不断同In和P结合,氧化层的厚度随时间几乎是线性地增加的。与InP的自体氧化层的俄歇深度分布相比较,二者极为相似,所不同的是,电子束感应吸附的氧不足以使表面层中的磷全部氧化,而ESO的氧化层中磷的 关键词：

ELECTRON STIMULATED ADSORPTION STUDY OF OXYGEN ON InP CLEAN SURFACE

The interactions of H₂O and O₂, with InP clean surface in the high vacuum chamber have been studied by means of Auger electron spectroscopy. It has been found that the water vapor plays a significant role responsible to the electron stimulated adsorption of oxygen than the pure oxygen. The In and P Auger signals change substantially during the oxygen adsorption process which is accessible as an occurence of electron stimulated oxidation (ESO). The oxygen atoms bond only with surface In atoms but not with P at the earliest stage, then they penetrate into the bulk and conbine with both In and P continually making the surface layer convert into oxide with an almost constant oxidation rate. As compared with the Auger depth profiling of InP native oxides, the similarity of the ESO and the ordinary oxidation processes is obvious. But the electron stimulated adsorpted oxygen could not fully oxidize the phosphorus in the surface layer while thermal oxidation and anodic oxidation do, the P concentration in the ESO oxide is higher than that in the thermal oxide but lower than the anodic oxide.