WORK FUNCTION CHANGE MEASURED BY ELECTRON-BEAM CHOPPING TECHNIQUE AS APPLIED TO OXYGEN-ADSORBED W(100) AT HIGH-TEMPERATURE

The electron beam chopping technique has enabled the true secondary electrons to be extracted from the overcoming background of thermionic and stray electrons, leading to a precise assessment of the work function change from the measurement of the onset of the spectrum. This technique was applied to the O/W(100) system at similar to 1100 K. The work function has revealed a stepwise change against the oxygen exposure time.