PbI_2多晶膜的制备及其晶体结构  

Preparation and Crystal Structure of PbI_2 Polycrystalline Film

作　　者：朱兴华[1] 杨定宇[1] 魏昭荣[1] 杨维清[1] 孙辉[1] 李乐中[1] 高秀英[1] 

机构地区：[1]成都信息工程学院光电技术学院,成都610225

出　　处：《人工晶体学报》2010年第3期719-723,共5页Journal of Synthetic Crystals

基　　金：国家自然科学基金(50902012);四川省应用基础研究项目(2009JY008)

摘　　要：采用电子束蒸发法制备PbI2多晶膜,研究了制备条件对沉积速率和晶体结构的影响。结果表明,源-衬间距和衬底温度对沉积速率的影响不具单调性,沉积速率随源-衬间距增大、衬底温度升高呈波动起伏。不同条件下制备的PbI2膜均属六方结构,但结晶质量和择优生长晶面存在差异。实验发现,随着膜层厚度增大,样品的结晶质量提高,当膜厚超出某一临界值,其结晶质量出现明显的下降。同时,随着衬底温度升高,PbI2膜的择优生长方向由80℃的(110)晶面转变为120℃的(001)晶面,且高级次(002)、(003)、(004)晶面的衍射峰逐渐增强,样品的c轴择优取向生长更加明显。综合以上,在电子枪束流25mA、电压6.5kV,源-衬间距30cm、衬底温度160℃的条件下,采用电子束蒸发制备的PbI多晶膜具有最佳的结晶性能。Polycrystalline Lead iodide （PbI2） films were prepared by electron beam evaporation,and the effect of deposition parameters on the deposition rate and crystal structure was studied.The results show that the deposition rate fluctuated as the source to substrate distance increasing or substrate temperature increasing.XRD patterns of samples reveal that PbI2 films prepared under different conditions is hexagonal structure,but different in crystal quality and preferred orientation.It is found that crystal quality of the samples improves as the film＇ s thickness increasing;however,a decline of crystallinity occurs when the thickness exceeds a critical value.In addition,the preferred orientation of samples changes from （110） plane to （001） plane when the substrate temperature increases from 80 ℃ to 120 ℃.As the substrate temperature further increasing,the diffraction peak intensity of （002）,（003）,（004） planes are gradually enhanced,which indicates c-axis preferred orientation improving.Based on the above,the optimized parameters were presented,that is the electron beam and high voltage were respectively 25 mA and 6.5 kV,the source to substrate distance fixed at 30 cm and keep the substrate temperature at 160 ℃.Under this condition,the samples prepared on glass substrates possess the best crystalline properties.

关 键 词：PbI2多晶膜 沉积速率 源-衬间距 衬底温度 

分 类 号：O484.1[理学—固体物理]