In-situ magnetron sputtering co-deposition of Ge nanoparticles in Si 3 N 4 films for near infrared detection

Deposition of Ge nanoparticles in Si 3 N 4 films by heating Si and quartz substrates at 500 °C were obtained using co-sputtering Ge, and Si3N4. Their structure and photo-electrical behaviour were investigated by transmission electron microscopy, current – voltage and spectral photo-current investigations, respectively. The spectral photoresponse were correlated with microscopy results. Depending on the measuring temperature, the current under illumination increases with about five orders of magnitude compared with the dark one. The photo-current spectra measured in photovoltaic regime and at -1 V show a single cut-off wavelength in near infrared domain at about 1362 nm.