Work function of MgO single crystals from ion-induced secondary electron emission coefficient

Ajou University, Sŏul, Seoul, South Korea
Journal of Applied Physics (Impact Factor: 2.19). 07/2003; 94(1). DOI: 10.1063/1.1581376

ABSTRACT The work functions ϕω of MgO single crystals with its respective orientation (111), (200), and (220) have been investigated from their ion-induced secondary electron emission coefficient Γ, respectively, using various ions with different ionization energies in a Γ-focused ion beam system. The work function ϕω for MgO single crystal with (111) orientation has the lowest value, 4.22 eV, whereas it is 4.94 eV for (200) and the highest value is 5.07 eV for (220). These work functions of MgO single crystals can explain the nonzero values of the ion-induced secondary electron emission coefficient Γ for Xe+ ions, whose ionization energy is 12.13 eV.

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