Strong orange/red electroluminescence from hydrogenated polymorphous silicon carbon light-emitting devices

We report on electroluminescent P-I-N diodes containing silicon nanocrystals embedded in an amorphous silicon carbon matrix as emitting material. The as-deposited devices mostly contain amorphous Si nanoparticles and emit weakly in the IR. After a forming process consisting of the application of a high current density to the structure, the intensity of the electroluminescence increases by a factor of 30 and shifts to the red. The forming process is characterized by electroluminescence measurements and the induced crystallization of the nanoparticles is evidenced by Raman scattering spectroscopy measurements. These results are interpreted as a metal induced crystallization.