Abstract
We are developing a system which measures the secondary electron yield (γ-value) of MgO films. The γ -value is determined by measuring the secondary electron current ejected from the sample irradiated by a mass analyzed ion beam of 50〜1000 eV. To improve the S/N ratio the system is designed to suppress electrons generated in the beam transport and to keep the vacuum pressure lower than 10^<-7>Pa. Prior to the construction of this system, we measure γ-values of W and MgO films by Xe ion beam irradiation using an existing low energy ion beam facility. Two kinds of MgO samples were evaporated on stainless steel with different orientations. The obtained γ-value for W is constant over the energy range from 100 to 1000 eV and about 0.02. The γ-value for MgO film showed energy dependence and difference with orientation.
