Luminescence properties of Ge-implanted SiO2 layer on Si substrate for blue-UV light source with low-voltage drive

The luminescence properties from shallowly Ge-implanted SiO₂ layer were investigated for the purpose of fabrication of optical light source in blue-UV range at very low voltage operation. Germanium negative ions were implanted into 50-nm SiO₂ layer on Si at very shallow depth from the surface to several tens nm at 10-50 keV and different incident angles. After post annealing, we measured photoluminescence and electroluminescence properties. We have obtained PL peaks at 290 nm and 390 nm in wavelength. In the EL measurement by applying AC voltage between the comb-shape transparent ITO electrode deposited on the SiO₂ surface and the Al electrode on Si rear side, the considerably strong EL peak was obtained at around 390 nm in wavelength at AC 20 volts.