MOCVD growth of gallium and indium microparticles for SERS applications

Abstract

The MOCVD growth of Ga and In microparticles was performed on graphene/SiC substrates. The test of effectiveness of the microparticles grown for SERS was based on the observation of H–Si vibrations on hydrogenated graphene grown on SiC. It was shown by scanning electron microscopy that the Ga or In microparticles grown were in the form of hemispheres with a flat side attached to the substrate. Raman measurements have shown that the effective H–Si SERS signal arises at the edges of the hemisphere microparticles. In addition, it was found that Ga or In microparticles are covered by GaAs or InAs shells, respectively. The presence of GaAs and InAs coverage of metallic microparticles arises from the As contamination of the MOCVD system used for III–V compound growth. However, these coverages do not significantly affect the surface plasmons resonance in the metallic microparticles.