Enhanced Field Emission from Graphene Flakes Enhanced Synthesized using PECVD

In the present work, uniformly distributed high-quality graphene flakes have been successfully synthesized on copper substrate at low temperature. at 550 °C by using plasma enhanced chemical vapor deposition (PECVD) system. The PECVD method is cost effective, highly efficient as well as low temperature phenomena for the synthesis of carbon based nanostructures. The as grown samples were characterized using different techniques such as field emission electron microscope (FESEM), high resolution transmission electron microscope (HRTEM), Raman spectroscopy and atomic force microscopy (AFM). The electron microscopic micrographs revealed the surface morphology of the graphene samples. From the micrographs, uniformly distributed flakes type structure has been observed. Raman spectra have shown that the structure of graphene flakes is of high quality with insignificant defects. From the G and G′ peaks, stokes phonon energy shift has been observed which is caused due to laser excitation. The high resolution AFM image also depicts the synthesis of graphene flakes. The field emission characteristics of as-grown graphene samples were also studied in diode configuration. The graphene flakes were observed to be extremely good field emitter having enhanced field amplification factor, low turn-on field, and long term emission current stability. (author)