GROWTH OF GAN ALN AND ALGAN BY MOCVD USING TRIETHYLGALLIUM AND TRITERTIARYBUTYLALUMINIUM/

Films of aluminium nitride (AlN) with thicknesses in the range from 20 0 to 3600 Angstrom have been deposited at 1050 degrees C by low-pressu re MOCVD. Using an alternative precursor, tritertiarybutylaluminium (( t)Bu(3)Al), and ammonia (NH3), we have grown AlN on sapphire (c-Al2O3) . At a growth rate of 0.35 mu m/h, the FWHM of the rocking curve measu red by X-ray diffraction was 150 arcsec. Therefore, we used the thin A lN films as buffer layers for the deposition of gallium nitride (GaN) at 950 degrees C using triethylgallium (Et(3)Ga). Aluminium gallium ni tride (AlxGa1-xN) with aluminium contents x from 0 to 0.5 were grown u sing a mixture of Et(3)Ga and (1)Bu(3)Al. The structural and optical p roperties of GaN, AlGaN and AlN were verified by X-ray diffraction (XR D), spectrally resolved photoconductivity (SPC), photothermal deflecti on (PDS) and photoluminescence spectroscopies.