A UV‐light‐emitting homojunction ZnO LED is grown by radiofrequency sputtering at high temperature, improving the structural, electrical, and optical properties of the n‐ and p‐type ZnO layers. The figure shows a comparison of the electroluminescence spectra of A) a p–n homojunction ZnO LED and B) a ZnO LED with Mg0.1Zn0.9O layers used as energy barrier layers. Such materials are of interest for their potential use in long‐lifetime solid‐state lighting, high‐density information storage, secure communication, and chemical/biological‐agent monitoring.

Disorder induced semiconductor to metal transition and modifications of grain boundaries in nanocrystalline zinc oxide thin film J. Appl. Phys. 112, 073101 (2012) Robust low resistivity p-type ZnO:Na films after ultraviolet illumination: The elimination of grain boundaries Appl. Phys. Lett. 101, 122109 (2012) P-type ZnO thin films achieved by N+ ion implantation through dynamic annealing process Appl. Phys. Lett. 101, 112101 (2012) Controlling the resistivity gradient in aluminum-doped zinc oxide grown by plasma-enhanced chemical vapor deposition J. Appl. Phys. 112, 043708 (2012) Schottky solar cells based on CsSnI3 thin-films Appl.

Surface-architecture-controlled ZnO nanowires were grown using a vapor transport method on various ZnO buffer film coated c-plane sapphire substrates with or without Au catalysts. The ZnO nanowires that were grown showed two different types of geometric properties: corrugated ZnO nanowires having a relatively smaller diameter and a strong deep-level emission photoluminescence (PL) peak and smooth ZnO nanowires having a relatively larger diameter and a weak deep-level emission PL peak. The surface morphology and size-dependent tunable electronic transport properties of the ZnO nanowires were characterized using a nanowire field effect transistor (FET) device structure. The FETs made from smooth ZnO nanowires with a larger diameter exhibited negative threshold voltages, indicating n-channel depletion-mode behavior, whereas those made from corrugated ZnO nanowires with a smaller diameter had positive threshold voltages, indicating n-channel enhancement-mode behavior.