Group III-V class materials are well known for their tunability across the UV-Visible and Infrared range. Earlier research was focused on Arsenic based materials such as GaAs and InGaAs and their application in the visible and IR range by MOCVD.
Group III-nitrides have stirred the electronic and optoelectronic industry quite a bit because of their high band gap nature in case of AlN and GaN suitable for UV and HEMT technologies and InGaN and InN for Visible and IR range optoelectronic applications. Extensive research is being carried out to combat several problems such as efficiency droop of Multi Quantum well based LEDs, phase separation of InGaN at higher Indium content, integration with the matured Silicon technology. Major thrust has been given for the growth of Group III-nitrides along non-polar and semipolar orientations to overcome the huge spontaneous polarization which hinders the performance of polar based devices and constant efforts are being put to improvise the quality of non-polar based devices.
Nanostructures of GaN, InN and InGaN have been grown using the bottom-up approach and fundamental studies have been carried out to realize their potential. The as-grown nanostructures have been characterized using several sensitive techniques such as Scanning tunneling microscopy and scanning tunneling spectroscopy to determine the size and bandgap variations with different growth conditions.