Here, Demir et al. (Article No. 1600363) demonstrate the pulsed atomic layer epitaxy AlN layers that have been grown on a 200 nm period of nano-patterned Si (111) substrates by a cantilever epitaxy via MOCVD, and compared with AlN layers grown by a maskless lateral epitaxial overgrowth (LEO) on micro-patterned Si (111) substrates. The material quality of 5-10 μm thick AlN grown by LEO is comparable to that of the much thinner layers (2 μm) grown by cantilever epitaxy on the nano-patterned substrates. Back emission ultra violet light emitting diodes (UV LEDs) were fabricated by flip chip bonding to patterned AlN heat sinks, followed by a complete Si (111) substrate removal, demonstrating a peak pulsed power of ~0.7 mW at 344 nm peak emission wave-length. Additionally, this study features the first demonstration of UV LEDs on nano-patterned Si substrates.