  To integrate plasmonic devices into industry, it is essential to develop
scalable and CMOS compatible plasmonic materials. In this work, we report high
plasmonic quality titanium nitride (TiN) on c-plane sapphire by plasma enhanced
atomic layer deposition (PE-ALD). TiN with low losses and high metallicity was
achieved at temperatures below 500{\deg}C, by exploring the effects of
chemisorption time, substrate temperature and plasma exposure time on material
properties. Reduction in chemisorption time mitigates premature precursor
decomposition at T_S > 375{\deg}C , and a trade-off between reduced impurity
concentration and structural degradation caused by plasma bombardment is
achieved for 25s plasma exposure. 85 nm thick TiN films grown at a substrate
temperature of 450{\deg}C, compatible with CMOS processes, with 0.5s
chemisorption time and 25s plasma exposure exhibited a high plasmonic figure of
merit (|{\epsilon}^'/{\epsilon}^''|) of 2.8 and resistivity of 31
{\mu}{\Omega}-cm. These TiN thin films fabricated with subwavelength apertures
were shown to exhibit extraordinary transmission.
