退火对CdTe薄膜性质影响

Effect of Annealing on Properties of Cdte Films

使用近间隔升华法制备碲化镉(CdTe)多晶薄膜,然后在不同的条件下进行退火处理.采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、X射线光电子能谱(XPS)和俄歇电子能谱(AES)对样品进行测试.结果表明刚沉积的CdTe薄膜呈立方相,并沿<111>晶向高度择优取向;退火后晶粒明显长大,且晶界减少.退火处理可以降低电流载流子的复合概率,有效地提高太阳电池的并联电阻和减少漏极电流.通过对X射线光电子能谱的详细分析发现,碲氧化物的存在及其含量随着深度的增加而减少,并且可能存在TeCl_(2)O.

Polycrystalline CdTe thin films were prepared by close-spaced sublimation(CSS)and annealed in different condition.The thin films were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and Auger Electron Spectroscopy(AES).XRD patterns show that as-deposited CdTe thin films are in a cubic phase and have the preferred orientation in(111)direction.After annealed,crystal grains grow up and crystal boundary decrease.The compound probabilities of current carrier decrease therefore shunt resistance and drain current are improved greatly.Detailed analysis of X-ray photoelectron spectroscopy shows that the presence and content of tellurium oxide decrease with increasing depth,and TeCl_(2)O may be present.