We report recrystallization of epitaxial (epi-) GaN(0001) film under indentation.Hardness value is measured close to 10 GPa, using a Berkovich indenter. Pop-in burst in the loading line indicates nucleation of dislocations setting in plastic motion of lattice atoms under stress field for the recrystallization process. Micro-Raman studies are used to identify the recrystallization process. Raman area mapping indicates the crystallized region. Phonon mode corresponding to E2(high) close to 570 cm-1 in the as-grown epi-GaN is redshifted to stress free value close to 567 cm-1 in the indented region. Evolution of A1(TO) and E1(TO) phonon modes are also reported to signify the recrystallization process.
@article{arxiv.0804.1824,
title = {Recrystallization of epitaxial GaN under indentation},
author = {S. Dhara and C. R. Das and H. C. Hsu and Baldev Raj and A. K. Bhaduri and L. C. Chen and K. H. Chen and S. K. Albert and Ayan Ray},
journal= {arXiv preprint arXiv:0804.1824},
year = {2008}
}