Helicon-Wave-Excited-Plasma Sputtering as an Expandable Epitaxy Method for Planar Semiconductor Thin Films

The helicon-wave-excited-plasma sputtering epitaxy (HWPSE) method was exemplified to grow atomically-smooth semiconductor epilayers of good structural and optical qualities. For a case study, ZnO homoepitaxy was carried out. According to the surface damage-free nature, the Zn-polar ZnO epilayers grown above 950 degrees C exhibited a smooth surface morphology with 0.26-nm-high monolayer atomic steps, of which tilt and twist mosaics were comparable to those of the substrate. Their room temperature photoluminescence (PL) spectrum was dominated by the free-excitonic emission. Clearly split PL peaks originating from A-exciton polaritons and sharp peaks due to the first excited-state excitons were observed at low temperature. (C) 2009 The Japan Society of Applied Physics DOI: 10.1143/APEX.2.105503