Nanopatterned Surface Effect on the Epitaxial growth of InGaN/GaN Multi-quantum Well Light Emitting Diode Structure

The authors fabricated a nanopatterned surface on a GaN thin film deposited on a sapphire substrate and used that as an epitaxial wafer on which to grow an InGaN/GaN multi-quantum well structure with metal-organic chemical vapor deposition. The deposited GaN epitaxial surface has a two-dimensional photonic crystal structure with a hexagonal lattice of 230 nm. The grown structure on the nano-surface shows a Raman shift of the transverse optical phonon mode to 569.5 cm-1, which implies a compressive stress of 0.5 GPa. However, the regrown thin film without the nano-surface shows a free standing mode of 567.6 cm-1, implying no stress. The nanohole surface better preserves the strain energy for pseudo-morphic crystal growth than does a flat plane. KCI Citation Count: 1