OPERATION OF ELECTROLUMINESCENT POROUS SILICON DIODES AS SURFACE-EMITTING COLD CATHODES

Cold electron emission properties of porous silicon (PS) electrolumine scent diodes have been investigated as a function of the top metal ele ctrode thickness, surface work function, and the thickness of PS layer . It is shown that the best thicknesses for Pt and Au electrodes are 5 0 - 80 Angstrom. The emission is enhanced by introducing an Al-Mg allo y electrode with a relatively low work function. Although the emission efficiency and the threshold voltage show definite dependencies on th e thickness of PS layer, the Fowler-Nordheim plots show a linear behav ior in every case. The maximum emission current density and efficiency obtained in this study are 10 mu A cm(-2) and 10(-3), respectively.