We show that the atomic layer deposition (ALD) technique has great potential for widespread use in the production of ZnO films for applications in electronic, photovoltaic (PV), and optoelectronic devices. The low growth temperature makes ALD-grown ZnO films suitable for fabrication of various semiconductor/organic hybrid structures. This opens up the possibility of novel devices based on very cheap organic materials, including organic light emitting diodes and third-generation PV cells.
We report on plasma-assisted molecular beam epitaxial growth of GaN nanowires (NWs) on Si(111) substrates with a thin amorphous Al2O3 buffer layer deposited by atomic layer deposition. Comparison of nucleation kinetics shows that presence of amorphous Al2O3 buffer significantly enhances spontaneous nucleation of GaN NWs. Slower nucleation was observed on partially amorphous silicon nitride films. No growth of NWs was found on sapphire substrate under the same growth conditions which we explain by a low density of defects on monocrystalline substrate surface where NWs may nucleate. Our finding shows that tuning of substrate microstructure is an efficient tool to control rate of self-induced nucleation of GaN NWs.