Control of strain in GaN using an In doping-induced hardening effect

Abstract

We study the hardening effect by isoelectronic In doping on strain in GaN grown by metalorganic vapor phase epitaxy. Incorporated In into GaN was found to pin the slip of screw dislocations, producing internal resistance stress in GaN as a result of the hardening of GaN. We found that this result is due to the interaction between In atoms and screw dislocations. The calculated stress in GaN yielded by the interaction was found to be in good agreement with the measured stress by x-ray diffraction and Raman spectroscopy. The internal resistance stress was estimated to be 0.3 GPa at maximum.