  This study presents a comprehensive investigation into the exceptional
superconducting attributes of titanium nitride (TiN) achieved through
plasma-enhanced atomic layer deposition (PEALD) on both planar and intricate
three-dimensional (3D) structures. We introduced an additional substrate
biasing cycle to densify the film and remove ligand residues, augmenting the
properties while minimizing impurities. While reactive-sputtered TiN films
exhibit high quality, our technique ensures superior uniformity by consistently
maintaining a desired sheet resistance greater than 95 percent across a 6inch
wafer, a critical aspect for fabricating extensive arrays of superconducting
devices and optimizing wafer yield. Moreover, our films demonstrate exceptional
similarity to conventional reactive-sputtered films, consistently reaching a
critical temperature (Tc) of 4.35 K with a thickness of around 40 nm. This
marks a notable achievement compared to previously reported ALD-based
superconducting TiN. Using the same process as for planar films, we obtained Tc
for aspect ratios (ARs) ranging from 2 to 40, observing a Tc of approximately 2
K for ARs between 2 and 10.5. We elucidate the mechanisms contributing to the
limitations and degradation of superconducting properties over these aggressive
3D structures. Our results seamlessly align with both current and
next-generation superconducting technologies, meeting stringent criteria for
thin-film constraints, large-scale deposition, conformality, 3D integration
schemes, and yield optimization.
