Preparation And Characteristic Research Of Double-color Response MgZnO_BST/STO Thin Film

Multicolor response films are of great significance in the field of disaster monitoring,urban fire protection and security,this work made ZnMgO_BST films with double color response of preparation under the method of pulsed laser deposition(PLD).Firstly,a LSMO buffer layer was grown in STO substrate,then Zn1-xMgxO(x=0.1?0.3?0.5)thin film on was prepared on one end of the buffer layer samples,and at the other quarter of end of the buffer layer samples prepared BST thin films respectively.For ZnMgO films,the features of samples were prepared by using X-ray diffraction(XRD),atomic force microscope(AFM),absorption spectrum test means.This paper discusses how the doping amount of Mn influences the photoelectric characteristics of the structure,morphology and surface.In addition,the work studied volt-ampere characteristic of the ZnMg the feature O films and the effect of laser energy on transient response characteristics of thin films.As for the BST thin films,the work mainly aimed at studying the photoelectric,ferroelectric,dielectric and pyroelectric properties of the films.Meanwhile,the paper tested the system.The main work and results are as follows:(1)The preparation process of target material are introduced,including two different methods and technology of sintering the LSMO and BST as the target material.(2)The ZnMgO thin film X-ray diffraction pattern shows that the different Mg contents in Zn1-xMgxO film corresponded two different lattice structures respectively.when doped-Mg content X is less or equal to 0.3,Zn1-xMgxO film keeps wurtzite structure.when X is 0.5,Zn1-xMgxO film becomes into cubic structure of sphalerite.With the increase of the Mg doping amount,the main diffraction peak of Zn1-xMgxO film drift in the direction of large Angle.Main peaks of the STO single crystal substrate(100)and(200)are near the 23 ° and 47 °respectively.The growth of thin films are in(100)preferred orientation.The main peaks of the BST single crystal substrate(100)and(200)are near the 22 ° and 46 ° respectively,which hasgood crystallinity and growth in the direction(100).(3)The Zn1-xMgxOthin film forbidden band width can be gotten by the absorption spectrum fitting analysis method.The results show that the Zn1-xMgxO film(x = 0.1,0.3,0.5)forbidden band width is 3.4 eV,4.35 eV and 5.4 eV respectively.It can be seen When the Mg element doping amount reached 0.5,ZnMgO has reached the blind band of the band gap.(4)The resistance of ZnMgO films decreased sharply after adding light resistance,then continued declining,and after moving the light source,the resistance would rise slowly,but it needs to take some time to return to the initial value.The photoelectric effect of thin film under the laser energy of 90 m J is weak,while in high-energy 135 mJ light photoelectric effect is stronger.But the overall effect is strong,predicting ZnMgO films for illumination effect is obvious.(5)The resistance of the BST thin films decreased suddenly after adding light,and then slowly rose.The resistance will slowly decrease down to the initial value after moving the light.The photoelectric effect of thin film under the laser energy of 90 mJ is weak,and in high-energy135 mJ light the effect is stronger.But the overall effect is weak,speculating that the BST thin films effects unconspicuously on light.(6)The interface resistance of the BST thin films will increase with the temperature increases.With the temperature increases,the interface resistance increases progressively.Interface resistance of BST thin films is larger and larger with the increase of light energy,but the overall change trend is small,the reason of this phenomenon may be the influence of light on BST thin films.(7)BST thin film dielectric constant increases slowly in the condition of low temperature,while the dielectric constant falls sharply with the increase of temperature after reaching the maximum.Thin film dielectric loss appears the trend of increasing first and then decreasing,and exists loss peaks,and with the increase of frequency,the loss peak in the films shifted to low temperature and peak loss peak also decreases.(8)BST thin films has good ferroelectric properties,which was influenced by the spontaneous polarization,and this work has measured the pyroelectric coefficient of the BST thin films is1.35×10-9C·cm-2·K-1— 1.83×10-8C·cm-2·K-1,which has reached the range of pyroelectric infrared detector parameters.