Studies were carried on the growth behavior of InN nanodots by plasma assisted molecular beam epitaxy on
bare Si(100) substrates and their structural, optical, electrical properties. The growth was carried out by two different
methods such as, (i) mono-step growth process at a low temperature and a (ii) bi-step growth process with the
combination of low and high temperatures for the formation of single crystalline nanodots with well defined
crystallographic facets due to cluster migration. Low temperature photoluminescence shows a free excitonic (FE)
luminescence at 0.80 eV. The Raman spectroscopy and X-ray diffraction studies reveal that the nanodots as well as
the film were of wurtzite structure and strain free.
The growth of nonpolar a- plane (1 1 -2 0) orientation of the GaN epilayers were confirmed by high resolution x-ray
diffraction studies. An in-plane orientation relationship was found to be [0 0 0 1] GaN || [-1 1 0 1] sapphire and [-1 1 0 0]
GaN || [1 1 -2 0] sapphire. SEM image shows the reasonably smooth surface. The photoluminescence spectrum shows
near band emission (NBE) at 3.439 eV. The room temperature I-V characteristics of Au/a-GaN schottky diode
performed. The Schottky barrier height (φb) and the ideality factor (η) for the Au/a-GaN schottky diode found to be 0.50
eV and 2.01 respectively.