Research On Energy Transfer Mechanism Based On Group ? Nitride Semiconductor Compound Structure

Non-radiation resonance energy transfer is the transfer of energy between excitons through a non-radiation process.It is widely used in high-efficiency white light device manufacturing and full-color micro-LED displays.Localized surface plasmon(LSP)has coupling properties with excitons in the luminous body and photons in free space,which can be used to overcome the limitation of the distance between the donor and acceptor in non-radiative resonance energy transfer.Plasmonic enhancement of the non-radiative resonance energy transfer mechanism of III-nitride semiconductors has important scientific significance and research value.In this thesis,metal-organic chemical vapor deposition and high-temperature rapid annealing technology are used to prepare a quantum well-metal-quantum dot hybrid structure with different LSP resonance wavelengths,and use time-resolved spectroscopy to characterize the structure,and finally prove the local surface Plasmonic excimer enhances non-radiative resonance energy transfer and reveals the mechanism of complex recombination process inside the structure.The main research contents and results of this paper are as follows:(1)The optical properties of different metals are simulated by the time-domain finite element method.By comparing the LSP resonant peak ranges of different metal nanoparticles,it is determined that the use of metallic Ag nanoparticles can produce the best LSP resonance effect with In Ga N quantum wells.Then,optical simulations of Ag nanoparticles with different diameters were carried out,which theoretically revealed the dependence of the LSP resonance wavelength on the size of the Ag nanoparticles,and proved that the LSP resonance wavelength can be controlled by the size of the Ag nanoparticles.(2)Experimentally designed and fabricated In Ga N quantum well-metal-quantum dot hybrid structures with different resonance wavelengths.Firstly,the self-assembly heat treatment technology of Ag nanoparticles was explored.By changing the vapor deposition thickness of the Ag film,The Ag nanoparticles with different diameters from 15 nm to 106 nm were realized.The resonance wavelength of the Ag nanoparticles is red-shifted from 465 nm to600nm as the particle size increases,which consistent with the theoretical simulation results.On this basis,Cd Se/Zn S quantum dots were spin-coated to prepare a quantum well-metalquantum dot hybrid structure.(3)Metal nanoparticles with different resonance wavelengths were proved to enhance the non-radiative resonance energy transfer between quantum dots and quantum wells by using time-resolved photoluminescence spectroscopy technology.Compared with the original NRET without Ag nanoparticles,the non-radiative energy transfer rate is increased by 6.9 times at the resonance wavelength of 600 nm,and the energy transfer efficiency is as high as 73.1%,which is almost twice the efficiency of the original NRET.The photoluminescence(PL)test shows that the luminescence intensity of quantum dots is determined by the quenching effect of Ag nanoparticles and LSP-enhanced NRET.And when the LSP resonance wavelength is at 465 nm,we demonstrate that the NRET mechanism enhanced by LSP can effectively enhance the luminous intensity of quantum dots.