Extinction properties of obliquely deposited TiN nanorod arrays

Abstract

Plasmonic titanium nitride (TiN) nanorod arrays (NRA) were fabricated by glancing angle deposition in a DC magnetron reactive sputtering system. The morphology of the TiN NRA was varied by collimating the vapor flux. The transmittance, reflectance, and extinctance of slanted TiN nanorods with different lengths as functions of wavelength and angle of incidence were measured and analyzed. The extinction peaks in the spectra reveal the transverse and longitudinal plasmonic modes of TiN NRA upon excitation by s-polarized and p-polarized light, respectively. The near-field simulation was performed to elucidate localized field enhancements that correspond to high extinction. The extension of the high extinction band with an increasing length of the nanorods results in broadband and wide-angle light extinction for a TiN NRA with a thickness greater than 426 nm.