Effect of isoelectronic in doping on deep levels in GaN grown by MOCVD

We have investigated the effect of isoelectronic In doping on deep levels i n GaN films grown by metalorganic chemical vapor deposition via deep level transient spectroscopy. Deep level E2 0.5 eV below the conduction band was observed in both undoped GaN and In-doped GaN. However, with increasing In mole flow rate, the trap concentration of E2 decreases sharply from 2.3 x 1 0(14) to 2.27 x 10(13) cm(-3), nearly an order of magnitude in reduction, c omparing to undoped GaN. This might be due to the dislocation pinning and/o r bending effect. Therefore, In doping in GaN growth can effectively decrea se the dislocation density and suppress the formation of deep levels E2.