Characterization of Mg-doped AlInN grown by metalorganic vapor phase epitaxy

We report on the growth of undoped and Mg-doped AlInN by metalorganic vapor phase epitaxy (MOVPE). The indium content and the full width at half maximum (FWHM) of undoped AlInN layer were 20.9% and 219.6 arcsec, respectively, from HRXRD measurement. It was also observed that an additional satellite peak was formed near the AlInN peak after introducing the Mg dopant. The sheet hole concentration of 4.73 x 1012 cm-2 was achieved after performing the thermal annealing. As the flow rate of Cp2Mg source was increased, we found that both the satellite peak and the AlInN peak shifted toward higher angles. However, higher Cp2Mg flow rate would not only decrease the conductivity of AlInN layer due to the higher Al content shown in HRXRD spectrum but increase the surface roughness. Therefore, these results suggest that p-type AlInN cladding layer nearly lattice-matched to GaN will be realized with lower Cp2Mg flow rate for optical device applications. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)