摘要
用探孔场发射显微镜研究了氧在W(100)面和W(111)面上的吸附和解吸过程。在3.8×10^(-6)Pa的氧压和291K的温度下吸附氧,W(100)面和W(111)面上功函数的最大增量分别为△φ^(max)^(100)=+1.6eV和△φ_(max)^(111)=+1.1eV。当吸附氧的场发射体从291K到1800K逐渐升温时,W(100)面和W(111)面的功函数的最小增量分别为△φ_(min)^(100)=-0.3eV(在1750K)和△φ_(min)^(111)=-0.5eV(在1700K)。对这两个晶面的实验结果进行了比较,并对其功函数增量最小值的产生给出了物理解释。
Adsorption and desorption of oxygen on the W (100) and the W(111) planes have been studied by using a prob - hole field emission microscope. Oxygen is dosed with a pressure of 3. 8×10^(-6)Pa and at 291K. The maximum increments of work functions in the W (100) and the W (111) planes are respectively △Φ_(max)^(100)=+1.6eV and △Φ_(max)^(111)=+1.1eV. When an emitter covered with adsorbed oxygen is gradually heated from 291K to 1800K,the minimum increments of work functions on the W (100) and W (111) planes are respectively △Φ_(min)^(100)=-0. 3eV at 1750K and △Φ_(min)^(100)=-0.5eV at 1700K. The experimental results on the W(100) and W (111) planes are compared. And the physical explanation of the minimum work - function increments is given.
出处
《真空科学与技术》
CSCD
1993年第5期305-310,共6页
Vacuum Science and Technology
关键词
场发射显微镜
吸附
解吸
氧
表面
Field emission microscope, Adsorption, Ddesorption: Work fonction
