Research On Luminescence Of ZnO Based Thin Films Enhanced By Al Metal Surface Plasmon

Surface plasmons is a kind of surface electro-magnetic wave,which exponentially decay perpendicular to the interface direction,and can be excited by electrons and photons.It has attracted much attention in various fields.There are also many reports about improving light emission of different materialsZinc Oxide(ZnO)has larger band gap and exciton binding energy.It also has good thermochemical stability.Therefore,ZnO has extensive application prospects in optoelectronic devices areas.Meanwhile,improving the light emission intensity and efficiency of ZnO based materials is necessary to promote its practical application.Taking use of metal surface plasmons to enhance the luminescence of ZnO based materials has been a new research hotspot currently.Considering this research hotpot,we prepared ZnO and ZnMgO thin films respectively,and utilize A1 surface plasmons to enhance the band edge emission.We also simulated the metal surface plasmons deeply through Finite Difference Time Domain(FDTD).The main contents of the work are as follows:ZnMgO films are grown by plasma-assisted.molecular beam epitaxy(P-MBE).59-fold enhancement of band-edge photoluminescence(PL)is obtained by sputtering Al nanoparticles on the surface of ZnMgO thin film.Besides,the internal quantum efficiency of the film is strongly increased from 6.2%to 21.41%,about 3.45-fold enhancement.We also investigate the stability of the enhancement ratio with time change,the enhancement ratio is stable after two months.Non-polar ZnO films are fabricated by plasma-assisted molecular beam epitaxy(P-MBE).Nano Al metal particles is prepared on the surface of the as grown films.To achieve the best coupling resonance effect,we utilize AlOx layer to mediate the energy of Al surface plasmons.84-fold enhancement of the band edge emission is achieved,and the internal quantum efficiency increased from 1.53%to 12.71%,which is increased about 8.3 times.In order to verily mediation of AlOx layer,the SPs energy of is simulated through FDTD.