Multifunctional Silicon Optoelectronics Integrated\nwith Plasmonic Scattering Color

Abstract

Plasmonic\nscattering from metallic nanoparticles has been used\nfor centuries to create the colorful appearance of stained glass.\nBesides their use as passive spectral filtering components, multifunctional\noptoelectronic applications can be achieved by integrating the nanoscatters\nwith semiconductors that generate electricity using the complementary\nspectral components of plasmonic colors. To suppress the usual degradation\nof both efficiency and the gamut of plasmonic scattering coloration\nin highly asymmetric index configurations like a silicon host, aluminum\nnanodisks on indium tin oxide (ITO) coated silicon were experimentally\nstudied and demonstrated color sorting in the full visible range along\nwith photocurrent generation. Interestingly, the photocurrents were\nfound to be comparable to the reference devices with only antireflection\ncoatings in spite of the power loss for coloration. Detailed investigation\nshows that ITO serves as both the impedance matching layer for promoting\nthe backward scattering and schottky contact with silicon, and moreover,\nplasmonic nanoscatters efficiently harvest the complement spectrum\ncomponents for charge generation. The present approach combines the\ncapacities of nanoscale color sorting and photoelectric converting\nat a negligible cost of efficiency, thus providing a broad flexibility\nof being utilized in various optoelectronic applications including\nself-powered display, filter-free imaging, and colorful photovoltaics.