Graphene/Si Schottky junction was modified with chromium and tin-doped indium oxide (ITO) nanoparticles. Chemical Vapor Deposition has been used to grow the graphene film which was subsequently transferred to substrate by the PMMA-assisted process. In order to obtain dispersed nanoislands on the graphene surface, the chromium coatings were prepared by pulsed DC magnetron sputtering, while the ITO coatings were prepared by pulsed RF. The chromium nanoparticles were deposited with different duty cycles, which were 50%, 75% and 90%. The ITO nanoparticles were deposited with different powers, which were 50 W, 60W and 70W. Raman was used to observe the characteristic of the graphene, which shows the defect of graphene after Cr and ITO deposition processes. The deposition of Cr and ITO result in p-type doping of graphene, since it shows the blue shift in Raman spectra. SEM and AFM was used to investigate the surface characterization of the nanoparticles. UV-Visible spectra were used to investigate the peak of surface plasmon resonance (SPR) of nanoparticles, which show the wide peak in the range 300 – 500 nm of wavelength. The Cr and ITO nanoparticles decorated Gr/Si photodetector show the self-powered characteristic and good improvement in the responsivity. The ON/OFF ratio of responsivity can be achieved up to 105. The fast response also can be achieved by the Cr and ITO nanoparticles decoration. The shortest time that can be achieved for rise time is 0.49 ms and for fall time is 0.47 ms. It shows a better performance of the photodetector compared to Gr/Si junction as the reference sample.

Graphene/Si Schottky junction was modified with chromium and tin-doped indium oxide (ITO) nanoparticles. Chemical Vapor Deposition has been used to grow the graphene film which was subsequently transferred to substrate by the PMMA-assisted process. In order to obtain dispersed nanoislands on the graphene surface, the chromium coatings were prepared by pulsed DC magnetron sputtering, while the ITO coatings were prepared by pulsed RF. The chromium nanoparticles were deposited with different duty cycles, which were 50%, 75% and 90%. The ITO nanoparticles were deposited with different powers, which were 50 W, 60W and 70W. Raman was used to observe the characteristic of the graphene, which shows the defect of graphene after Cr and ITO deposition processes. The deposition of Cr and ITO result in p-type doping of graphene, since it shows the blue shift in Raman spectra. SEM and AFM was used to investigate the surface characterization of the nanoparticles. UV-Visible spectra were used to investigate the peak of surface plasmon resonance (SPR) of nanoparticles, which show the wide peak in the range 300 – 500 nm of wavelength. The Cr and ITO nanoparticles decorated Gr/Si photodetector show the self-powered characteristic and good improvement in the responsivity. The ON/OFF ratio of responsivity can be achieved up to 105. The fast response also can be achieved by the Cr and ITO nanoparticles decoration. The shortest time that can be achieved for rise time is 0.49 ms and for fall time is 0.47 ms. It shows a better performance of the photodetector compared to Gr/Si junction as the reference sample.

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