Study Of Rare Earth Ions Doped Oxide Thin Films And Their Properties

Lithium niobate(LiNbO3)has a large ferroelectric,piezoelectric,electro-optical,acousto-optic,nonlinear optical properties,can be widely used in optical waveguide modulator,sensors,polarizers and other optical waveguide device preparation.Optical devices are a very important component in integrated optics.Thin film materials are fabricated in many ways better than bulk materials.Therefore,the deposition of Li NbO3(LN)thin films on silicon substrates and their properties will be studied for integrated optics And the development of optical communication play a certain role in promoting.Zinc oxide(ZnO)can have large bandgap,exciton binding energy is a good doping matrix,can be used for lighting,solar cells,conductive film and other research areas.Rare earth ions have a rich energy level structure,a wide range of light,and more used in the preparation of active devices.Er ion transition 4I13/2?4I15/2 emission wavelength is about1.54 ?m,the band corresponds to the plane waveguide minimum loss of transmission window.At room temperature,the transition of europium ion 5D0?7I2 emission wavelength is 618 nm,mostly used in signal lamp,probe,solid laser materials,medical and other fields.It is not a lot to study the active oxide thin films with low transmission loss and high fluorescence intensity by using pulsed laser deposition technique.It is difficult to control the doping concentration of rare earth ions in thin films and study the influence of rare earth ion concentration on the crystal quality of thin films.a lot of.Therefore,a series of selective oxide films were prepared on the SiO2/Si(111)substrate by changing the experimental deposition conditions by pulsed laser deposition.The films were characterized by X-ray diffraction(XRD),stepping instrument,prism coupling,fluorescence spectroscopy,high-power mirror,cold field emission scanning electron microscopy(FSEM)on the preparation of samples for a variety of physical properties of the following specific research content and research results:1.The preferential orientation of the LN film was deposited on the Si O2/Si(111)substrate by PLD technique.The effects of O2/Ar atmosphere,substrate temperature,oxygen pressure,pulse laser repetition frequency,The optimum experimental parameters were as follows: substrate temperature 500?,substrate-target distance 4cm,laser repetition frequency 3Hz,oxygen pressure 2.0Pa,800? cavity annealing treatment,LN ceramic target.Test film optical waveguide properties,surface morphology found: the deposition time is short sample surface is very smooth,dense grain but the thickness(200nm)too thin light is easy to enter the substrate,it is difficult to form a waveguide;deposition time is long The thickness of the sample is sufficient to form the waveguide,butthere are many cracks on the surface of the film.At present,the research group has not coupled the light into the sample.2.A series of Er: LN films were prepared by changing the experimental conditions on the SiO2/Si(111)substrate by PLD technique.The Er/LN composite target was not a fixed ratio.And Li double-target alternating and pulsed laser interaction deposition Er: LN film,which can be flexible control of rare earth ions doping concentration.The effect of substrate temperature,oxygen pressure and erbium target growth time on the mass of Er:LN film was investigated.It was found that the higher the substrate temperature,the better the crystal quality of the larger film.When the thickness of the deposited film was 800 nm,Reduced to polycrystalline.The samples were selected to have a wavelength of 513 nm laser pump sample.Before the experiment was started,the 840 nm filter was placed at the inlet of the sample cavity to effectively eliminate the effect of frequency doubling light.The test results showed that the sample was in the 1537 nm position strong photoluminescence peak.3.The preferential orientation of Eu: ZnO thin films was prepared on SiO2/Si(111)substrates by PLD technique.The effects of substrate temperature,oxygen pressure,pulse laser repetition frequency and growth time on the film quality were investigated.The higher the deposition time is,the longer the(002)diffraction peak of the sample is,and the effect of film thickness on the crystal quality of Eu: ZnO thin film is not obvious.The photocatalytic temperature of Eu: ZnO thin film is not obvious The The sample was pumped with xenon lamp with a pump wavelength of 466 nm.A 510 nm wavelength filter was placed before the sample.The photoluminescence peak intensity at 618 nm was higher than that of the target,indicating that the deposited Eu: ZnO thin film quality is relatively high.