Measuring the absorption of TiN metallic films using cathodoluminescence of GaN films

Although TiN thin metallic film has attractive prospects in plasma applications, its optical properties still remain less well explored. Here we have fabricated TiN thin metallic film with an average of about 50 nm thickness by pulsed laser deposition on p-GaN substrates at 650 degrees C. The morphology and crystal structure are characterized by atomic force microscopy and X-ray diffraction. The results exhibit a smooth surface and an obviously preferred ( 111) orientation. A combination of cathodoluminescence spectroscopy and a cross-sectional scanning electron microscopy is developed to study the absorption behavior of TiN thin metallic film systematically. The absorption coefficients of TiN thin metallic film obtained here are in good agreement with the values obtained by the spectroscopic ellipsometry. (C) 2017 Optical Society of America