  We report on the deposition of gallium oxide using microwave irradiation
technique on III nitride epi layers. We also report on the first demonstration
of a gallium oxide device, a visible blind deep UV detector, with GaN based
heterostructure as the substrate. The film deposited in the solution medium, at
less than 200 C, using a metalorganic precursor, was nanocrystalline. XRD
confirms that as deposited film when annealed at high temperature turns
polycrystalline beta gallium oxide. SEM shows the as deposited film to be
uniform, with a surface roughness of 4 to 5 nm, as revealed by AFM.
Interdigitated metal semiconductor metal MSM devices with Ni,Au contact
exhibited peak spectral response at 230 nm and a good visible rejection ratio.
This first demonstration of a deep-UV detector on beta-gallium oxide on III
nitride stack is expected to open up new possibilities of functional and
physical integration of beta gallium oxide and GaN material families towards
enabling next generation high performance devices by exciting band and
heterostructure engineering.
