Semipolar Single-Crystal ZnO Films Deposited by Low-Temperature Aqueous Solution Phase Epitaxy on GaN Light-Emitting Diodes
نویسندگان
چکیده
Low-temperature aqueous solution deposition has been used for the first time to produce epitaxial ZnO layers on the semipolar (10 1 1) surface of bulk GaN substrates and LEDs. Although the ZnO films have single in-plane and out-of-plane orientations, which are nominally the same as those of the (10 1 1) GaN substrate, the ZnO lattice is observed to be slightly tilted with respect to that of the substrate. A (10 1 1) light-emitting diode using an epitaxial ZnO film as a transparent current-spreading layer achieved a high external quantum efficiency of 48%. # 2011 The Japan Society of Applied Physics
منابع مشابه
High-Efficiency Single-Quantum-Well Green and Yellow-Green Light-Emitting Diodes on Semipolar (20\bar{2}1) GaN Substrates
We demonstrate high-efficiency green and yellow-green single-quantum-well light-emitting diodes (LEDs) grown on semipolar (20 21) GaN substrates by metal organic chemical vapor deposition. The output power and external quantum efficiency at a driving current of 20mA under a pulsed condition with a 10% duty cycle are 9.9mW and 20.4% for the green LED and 5.7mW and 12.6% for the yellow-green LED,...
متن کاملSemipolar InGaN/GaN Converters for Bright Green Emission and Stripe LEDs 59 Semipolar InGaN/GaN Converters for Bright Green Emission and Stripe Light Emitting Diodes
Optically pumped green converter structures based on three-dimensional (3D) inverse pyramids were studied. The green emission intensity is determined by the conversion rate ηc and the absorption fraction ηa, indicating the InGaN/GaN quantum well (QW) crystal quality and its absorption capability, respectively. 15 was found to be the optimal QW number based the epitaxial condition for that serie...
متن کاملFabrication of full-color InGaN-based light-emitting diodes on amorphous substrates by pulsed sputtering
InGaN-based light-emitting diodes (LEDs) have been widely accepted as highly efficient light sources capable of replacing incandescent bulbs. However, applications of InGaN LEDs are limited to small devices because their fabrication process involves expensive epitaxial growth of InGaN by metalorganic vapor phase epitaxy on single-crystal wafers. If we can utilize a low-cost epitaxial growth pro...
متن کاملCrystal Quality Improvement of Semipolar (202̄1) GaN on Patterned Sapphire Substrates by In-Situ Deposited SiN Mask
We present our results of (202̄1) GaN growth on (224̄3) patterned sapphire substrates. The substrates are patterned by etching trenches with c-plane-like side-facets. On these facets, the metalorganic vapor phase epitaxy (MOVPE) GaN growth starts in c-direction and forms triangularly shaped stripes eventually coalescing to a (202̄1) oriented layer. Xray rocking curves measured parallel to the stri...
متن کاملAn illustration of photocatalytic properties of ZnO nanorods array films
ZnO nanorods array films were coated on a glass template through a two-step chemical process. First, a sol-gel spin coating method was used to produce a ZnO seed layer and after that, the ZnO nanorods arrays were grown on it through a low temperature aqueous method. Synthesized films were studied by scanning electron microscope (SEM) and X-ray diffractometer (XRD). X-ray diffraction results sho...
متن کامل