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用俄歇谱及分子束技术就地与非就地研究了蒸发稀土金属镧薄膜的表面特性。一种情况是在镀膜机内制作镧薄膜，从镀膜机中取出，暴露在大气中，然后放入超高真空室内进行研究。另一种情况是La薄膜在超高真空室内制备并就地研究。结果表明，两种情况下获得的两样品的俄歇谱图不同。样品1的俄歇谐相当于表面组分主要为La（OH）3，它是由空气中的氧和水汽与表面作用形成的。样品2的俄歇谱相当于表面主要组分为La。少量的La（OH）3是La和超高真空室内的残余H2O作用的结果。用分子束技术对CH4在两样品表面的激活化学吸附特性进行了研究。实验发现初始粘着几率S0强烈地依赖于入射分子束的平动能，并以En＝Ecos2θi表征。在两种情况下都有初始粘着几率随平动能增大而线性增加。当样品表面温度由500K升至700K时，两样品的阈值能和活化能都不随表面温度变化，在相同气体作用下，阈值能和活化能仅由样品本身的结构和性质决定。
The surface properties of evaporated lanthanum metal lanthanum films were studied in situ and off-site using Auger spectroscopy and molecular beam techniques. In one case, a lanthanum film was produced in the coating machine, removed from the coating machine, exposed to the atmosphere, and placed in an ultra-high vacuum chamber for research. Alternatively, La films were prepared in an ultrahigh vacuum chamber and investigated in situ. The results show that the Auger spectra of the two samples obtained in the two cases are different. The Auger harmonic of Sample 1 is equivalent to that the surface component is mainly La (OH) 3, which is formed by the action of oxygen and water vapor in the air on the surface. Auger spectrum of Sample 2 corresponds to the major component of the surface being La. Small amounts of La (OH) 3 are the result of the action of La on the residual H2O in the ultra-high vacuum chamber. The molecular chemisorption of CH4 on the surface of two samples was studied by molecular beam technique. The experiment found that initial adhesion probability S0 strongly depends on the translational energy of the incident molecular beam and is characterized by En = Ecos2θi. In both cases, the initial adhesion probability increased linearly with increasing translational energy. When the surface temperature of sample increases from 500K to 700K, the threshold energy and activation energy of the two samples do not change with the surface temperature. Under the same gas, the threshold energy and activation energy are only determined by the structure and properties of the sample itself.