HgCl_2-KI-H_2O溶液体系中碘化汞(α-HgI_2)籽晶层生长研究  

Growth ofα-HgI_2 Seed Layer in HgCl_2-KI-H_2O

作　　者：赵盼盼[1] 许岗[1] 冯亚西 邱海蔡 李俊英[1] 

机构地区：[1]西安工业大学材料与化工学院,西安710021

出　　处：《西安工业大学学报》2016年第4期323-327,共5页Journal of Xi’an Technological University

基　　金：国家自然科学基金(51502234);陕西省教育厅科研计划项目(15JS040);2014年国家级大学生创新创业训练计划项目(201410702015)

摘　　要：为提高气相沉积碘化汞(α-HgI_2)多晶薄膜定向生长效果,研究了HgCl_2和KI溶液化合反应法制备用于同质外延的HgI_2籽晶层的生长工艺.建立了HgCl_2/KI=1∶1~1∶6(摩尔比)的反应体系,通过改变体系中碘离子([I]^-)浓度,研究了液相体系的反应过程.通过紫外-可见分光光度计研究了反应体系中组元转变特征,采用偏光显微镜分析了不同浓度下晶体结晶形貌和分布特征.UV光谱表明:随着[I]^-浓度增大,体系中出现[HgI2]n聚体并导致吸收峰红移,以及K[HgI_3]·H_2O吸收峰出现蓝移.宏观形貌分析表明:籽晶层粒度和覆盖度随[I]^-浓度增大而增大,晶粒逐渐发育充分.[HgI_2]n聚体的形成导致电子能级密度增加,跃迁能量降低,形成红移;孤对电子浓度增大在K[HgI_3]·H_2O出现电子从非键轨道向反键轨道的跃迁现象,形成蓝移.当HgCl_2/KI=1∶6时,覆盖度最佳.分析认为,控制高浓度体系中反应速率可降低晶粒堆垛现象.The oriented growth process of HgI2 seed layer was investigated in HgCl2-KI-H2O solution. The reaction mechanism in HgCl2 ＋KI＋H2O was studied when the mole ratio of HgCl2/KI varies from 1 ： 1 to 1 ： 6. Growth unit in system was determined by visible and UV spectrometers. The morphology of seed layer was observed using a LEICA-DM2500P polarizing microscope. The results show： Red shift occurs along with [HgI2]. polymer, and blue shift appears with complexes K[HgI3 ]· H2O. Through the discussions on the characterization of UV spectra,it is suggested：The size and coverage of grain increase with [I]^- concentration, and the sufficient grain develops gradually. The forming polymer [ HgI2] In results in increased density of electron energy levels, reduces transition energy,leading to red shift. Blue shift emerge is dictated that electron transits from nonbonding to antibonding in K [HgI3] · H2O, resulting from HgC12/KI = 1 concentration. increment of lone pair electron concentration. The best density of seed layer forms as ： 6. Grain stacking would be controlled by retarding the reaction in higher [I]^- concentration.

关 键 词：α-HgI2 定向生长 溶液法 覆盖度 

分 类 号：O782[理学—晶体学]