High performance NIR photosensitive films of Ge nanoparticles in Si 3 N 4

Films of amorphous Ge nanoparticles in S$i_{3}N_{4}$ on heated Si and quartz substrates at 300°c were obtained by co-sputtering Ge, and S$i_{3}N_{4}$. The films structure and photo-electrical behaviour were studied through transmission electron microscopy and, current- voltage and spectral photo-current investigations, respectively. The spectral photo-current were correlated with results obtained from transmission electron microscopy. Under illumination the current present a high increase with about one order of magnitude compared with the dark one. The photo-current spectra show a widening in near infrared to 0.97eV. Internal quantum efficiency values for-1V and 0V were determinedt