退火时间对PbS薄膜结构和光学特性的影响

Effect of Annealing Time on the Structural and Optical Properties of Chemical Bath Deposited PbS Thin Films

利用化学浴沉积法在玻璃衬底上50℃沉积3h制备硫化铅（PbS）纳米晶薄膜.将得到的PbS薄膜在300℃氮气中进行不同时间（0～120min）的退火.利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）、原子力显微镜（AFM）和紫外-可见-近红外分光光度计对PbS薄膜的结构和光学特性进行研究.PbS薄膜在玻璃基底上粘附力较强,结晶度良好,呈面心立方结构且沿（111）方向择优生长.不同的退火时间导致PbS薄膜的结构、形貌、光学特性均产生明显差异.退火30 min的PbS薄膜的结晶度最好,其带隙变化范围为0.90～1.70 eV.

Nanocrystalline PbS thin films were deposited on glass substrates at 50 ℃ for 3 h using chemical bath deposition technique and annealed at 300 ℃ for various annealing times in N2 （0--120 rain）. The structure of the prepared PbS thin films was studied by X-ray diffraction. Its surface morphology was measured by scanning electron mieroseope （SEM） and atomic force microscope （AFM）. Its optical properties in the wavelengths of 300--2000 nm were studied using UV-Vis-NIR spectrophotometer. The films are very adherent to the substrate and crystallized with preferential （111）. Different annealing time results in obvious difference of PbS thin films＇ structure,morphology and optical properties. PbS thin films obtained optimum crystalline in annealing time of 30 min and its optical gap varied between 0. 90--1.70 eV.