脉冲激光沉积法制备低阻掺镓氧化锌薄膜及其光电性能

Preparation of Low-Resistivity GZO Thin Films Using Pulsed Laser Deposition and Investigation of Optoelectronic Properties

采用脉冲激光沉积法在玻璃衬底上沉积掺镓氧化锌(GZO)透明导电薄膜,使用X射线衍射仪、紫外可见分光光度仪、原子力电子显微镜和霍尔测试系统,研究了氧气分压对GZO薄膜晶体结构、微观形貌以及光电性能的影响。结果表明:所有的样品都表现出六方纤锌矿结构,并具有高度的c轴择优取向生长;薄膜表面致密光滑,晶粒尺寸随氧气分压增大而先增大后减小,当氧气分压为0.5 Pa时,薄膜的结晶性最佳;沉积的GZO薄膜在可见光区域表现出高于91.97%的透过率,且禁带宽度在3.492~3.576 eV之间;随着氧气分压增大,载流子浓度与霍尔迁移率先增加后减小,电阻率先减小后增大,当氧气分压为0.5 Pa时,GZO薄膜的电阻率最低,为2.95×10^-4Ω·cm。

Ga-doped ZnO(GZO)transparent conductive thin films are deposited on glass substrates via the pulsed laser deposition method;further,the influence of oxygen pressure on the structure,surface morphology,and photoelectric properties of the GZO thin film is systematically investigated using X-ray diffractometer,ultraviolet-visible spectroscopy,atomic force microscopy,and Hall test system.Results show that all the samples exhibit a hexagonal wurtzite structure with a preferred orientation along the c-axis.Homogeneous,dense,and compact surfaces are obtained for all the GZO films.The crystal size initially increases and then decreases with the increasing oxygen pressure;optimum crystallinity is observed at an oxygen pressure of 0.5 Pa.The prepared GZO films exhibit a transmittance higher than 91.97%in the visible region;the band gap of the GZO film is 3.492-3.576 eV.The carrier density and Hall mobility initially increase and then decrease with the increasing oxygen pressure.The resistivity initially decreases when the oxygen pressure increases.However,with a further increase in the oxygen pressure,the resistivity increases.The minimum resistivity of 2.95×10^-4Ω·cm is observed when the oxygen pressure is 0.5 Pa.