TY - JOUR

T1 - Nitrogen flux induced GaN nanostructure nucleation at misfit dislocations on Al2O3

AU - Kesaria, Manoj

AU - Shivaprasad, S. M.

PY - 2011/10/4

Y1 - 2011/10/4

N2 - The work demonstrates the dominant role of nitrogen flux rate on GaN nanostructure formation on bare Al2O3(0001). In nitrogen rich conditions, wurtzite c-oriented GaN nanowall honeycomb network is formed as strain relaxation pathway of nucleation at edge dislocations. A specific nitrogen flux rate in a plasma assisted molecular beam epitaxy growth is necessary for fixed Ga flux and substrate temperature to form columnar self assembled nanostructures. It is argued that kinetically hindering diffusion of Ga adatoms and the low sticking coefficient of r and m planes of nanowalls promote 1-dimension nanocolumn formation at screw dislocations formed at the GaN-Sapphire interface.

AB - The work demonstrates the dominant role of nitrogen flux rate on GaN nanostructure formation on bare Al2O3(0001). In nitrogen rich conditions, wurtzite c-oriented GaN nanowall honeycomb network is formed as strain relaxation pathway of nucleation at edge dislocations. A specific nitrogen flux rate in a plasma assisted molecular beam epitaxy growth is necessary for fixed Ga flux and substrate temperature to form columnar self assembled nanostructures. It is argued that kinetically hindering diffusion of Ga adatoms and the low sticking coefficient of r and m planes of nanowalls promote 1-dimension nanocolumn formation at screw dislocations formed at the GaN-Sapphire interface.

KW - GaN Nanorods

KW - PA-MBE

U2 - 10.1063/1.3646391

DO - 10.1063/1.3646391

M3 - Journal article

VL - 99

JO - Applied Physics Letters

JF - Applied Physics Letters

SN - 0003-6951

IS - 14

M1 - 143105

ER -