The growth and characterization of GaN epilayers grown on Si(111) substrate using 3C-SiC intermediate layer

The GaN films have been grown oil Si(Ill) substrates using 3C-SiC intermediate layers by low pressure metalorganics chemical vapor deposition(LP-MOCVD). The SiC intermediate layer was grown by chemical vapor deposit ion (CVD) using tetramethylsilane(TMS, (CH3)(1)Si) ss the single source precursor. Single crystalline hexagonal GaN layers were grown successfully on 3C-SiC intermediate layer using AIN nucleation layer. For the growth of GaN epilayer the trimethylgallium (TMGa) flow was decreased from 60 mu mol/min to 26 mu mol/min at constant ammonia(NH3) flow of 4000 seem. We have observed that the surface morphology. crystal quality and optical properties of GaN epilayers are strongly dependent oil the flow rate of TMGa. The optimum flow rate of TMGa is 36 mu mol/min for the growth of GaN epilayer with AIN nucleation layer. The surface morphology of GaN epilayer at the flow rate of TMGa 36 mu mol/min was most smooth. This sample a strong near band edge emission in PL spectra at the room temperature with a full width at half maximum(FWHM) value of 38 meV, and also X-ray diffraction(XRD) front thc (0002)plane of GaN with FWHM of value of 960 arcsec. The lower flow rate of TMGa is, the GaN epilayers have bettor characteristics. but the surface below TMGa flow rate of 36 mu mol/min is not completely saturated.