AlN and GaN are highly important for optoelectronic applications and form the backbone in modern light emitting diode technology. The revised band gap of InN to 0.7 eV and its high electron mobility open up new opportunities; such as IR emitters, sensors , solar cells, thinfilm transistors , and high-electron mobility transistors . As all such applications are based on heterostructures with homogeneous coverage of nano-scale active layers, highly controlled InN epitaxy is paramount to realize any application.