Study On Piezoelectrically Controlled LEDs And QLED Based On ZnO Nanowire Arrays

Based on Professor Wang Zhonglin's 2007 and 2010 two original concepts of piezoelectric electronics and piezoelectric optoelectronics.The strain-induced interfacial polarization charge is used to modulate the energy band structure at the interface and thus to effectively regulate and control the carrier transport at the interface or junction region.The piezoelectric effect of the material is used to adjust the light emission of the light emitting diodes and the quantum dot light emitting diodes,which is an important way to realize pressure visualization.In this dissertation,we use ZnO nanowires to fabricate Ga N/ZnO heterostructure light-emitting diode arrays and excite quantum dot fluorescence and array QD lightemitting diodes.Piezoelectric effect is used to control the carrier transport of the device,and then the luminescence characteristics of the device and the response of the visualized stress are studied,providing experimental basis for practical application in the future.Mainly got some results.1.A grid electrode with a 30 ?m line width and 100 ?m pitch was prepared on a PGaN substrate by using ultraviolet lithography and magnetron sputtering techniques to improve the conductivity of the P-GaN substrate;after that,ultraviolet lithography and magnetics were used again.Controlled sputtering technique to fabricate a Si O2 mask array with 3?m pore size and 6?m pore spacing on the substrate,and hydrothermally epitaxially grow a single ZnO nanowire array on P-GaN;finally,the array GaN/was prepared by a packaging process.The ZnO heterojunction light-emitting diodes successfully excite the fluorescence of quantum dots spin-coated on the back surface of the device.The device test results show that the device has a typical PN junction IV characteristic curve,the on-voltage is about 10V;due to the defects of ZnO prepared by the hydrothermal method,the Ga N/ZnO heterojunction center wavelength is about 400nm;Ga N/ZnO is different.Luminescence luminescence and successful excitation of CsPb Br3,CdSe/Cd S/ZnS,Cd Se@Zn S/ZnS quantum dots spin-coated on the rear surface of the device.2.Using a vertically grown ZnO nanowire array with a 10 ?m aperture spacing of 5 ?m,a ZnO-based electron transport layer,a NPB organic material as a hole transport layer,and a CdSe/Cd S/Zn S,Cd Se@Zn S/Zn S quantum dot were designed and prepared.Quantum-dot light emitting diode devices that are luminescent materials.The devices were subjected to electrical test and electro-luminescence analysis was performed on the quantum dots.A quantum dot light emitting diode device emitting red light of 630 nm and 540 green light,respectively,was obtained.Finally,using the piezoelectric photoelectron effect of ZnO nanowires,the luminous intensity of the pixels in the device increases as the applied pressure increases.