Selective area mass transport regrowth of gallium nitride

Selective area mass transport regrowth of GaN was performed on wafers with etched wells and SiO2 mask. The samples were annealed in NH3 and H-2 flow, with no gallium precursor. At 1060 degreesC, only little mass transport occ ured, but the sidewall morphology changed, depending on crystallographic or ientation At 1160 degreesC, the sidewalls grew out about 1 mum in 1 min, in dependent of orientation. The technique can potentially be performed in an annealing chamber, providing a low cost regrowth process. A promising appli cation is ohmic contact regrowth to high composition AlGaN/GaN high electro n mobility transistors.