ABSTRACT
Since a decade ago time Ill-nitrides have attracted great interest stemmed from the success of their applications in many areas including optoelectronic devices for blue/UV spectral range, high power and high temperature electronic devices. A coming up issue of the nitride’s agenda is in finding more affordable technology to reduce the cost of device production. Recently achieved success with MBE growth of GaN layers on amorphous quartz (silica) glass substrate [1,2] led to the observation of efficient photoluminescence (PL) in spite polycrystalline structure of the samples. Moreover, n-and p-type doping of these layers was demonstrated [3]. A high quality polycrystalline GaN layers have been grown on metal substrates (Mo, Ta, W, Nb) [4]. These results light up the perspectives of fabrication cost-affordable large area photonic devises based on polycrystalline nitride layers [1]. However, further detailed research should shed light on the reasons for the highly efficient PL of these samples. In this paper we report the results on time-resolved PL studies of GaN films grown by MBE on Mo and Ta metal substrates.
