Characteristics of narrow-bandgap InN semiconductors grown on Ga-polar and N-polar GaN templates by pulsed metalorganic vapor phase epitaxy

Abstract

The growths of droplet-free narrow-bandgap InN semiconductors on Ga-polar and N-polar GaN templates on c-plane sapphire substrates were performed by pulsed-MOVPE growth techniques. Under the optimum In-polar InN growth conditions, the carrier mobility and n-type carrier concentration were measured as 681 cm 2 /(V.sec) and 1.5×10 19 cm -3 , respectively. The room-temperature photoluminescence measurements of optimized In-polar grown by pulsed-MOVPE technique resulted in peak wavelength at 0.76 eV. The growth of N-polar InN grown on the N-polar GaN template is discussed and compared to that of the In-polar InN.