CeO_2掺杂对ZnO薄膜气敏特性的影响

Abstract

znO薄膜进行CEO2掺杂,研究掺杂含量和热氧化对薄膜结构、表面、晶粒尺寸及气敏特性的影响。结果显示,用热蒸发制备的高纯zn膜经500℃热氧化,获得C轴取向znO多晶薄膜。掺CEO2可抑制晶粒生长使颗粒细化平均粒径减小,同时改善了znO薄膜的体相化学计量比,zn与O的比例从未掺杂时1∶1.28降到1∶1.191。XPS分析给出薄膜中zn显+2价,O为-2价。掺CEO2(9%)可大大提高薄膜对乙醇和丙酮的敏感性,灵敏度分别达35和40。

The doping effect of CeO2 in thin films structure,topography,grain size and gas sensing properties of ZnO thin films is investigated.The polycrystalline thin films with c-axis orientation can be obtained after thermal vacuum evaporation.The doping behavior can refine the grain size,simultaneously reduce the stoichiometric ratio from Zn∶O=1∶1.28 down to Zn∶O= 1∶1.191.The XPS results show that Zn existed as +2 and O as-2 states.Additionally,CeO2 doping can dramatically enhance the sensitivities to ethanol and acetone,reaching up to 35 and 40,respectively.