溶胶-凝胶法制备MgxZn1-xO薄膜及性能研究

采用溶胶-凝胶法在石英玻璃片衬底上制备了Mg2+掺杂的ZnO(MgxZn1-xO)薄膜,研究了Mg2+掺杂对ZnO薄膜结构和紫外透过率的影响;在氧化物薄膜上真空蒸镀了Al叉指电极,制得紫外原型探测器件,测试了I-Ⅴ特性.结果表明,Mg2+掺杂后,MgxZn1-xO薄膜为纤锌矿结构,随着x值增加,晶格常数c逐渐减少,α逐渐增大,Mg2+掺杂抑制了(002)晶面的生长;紫外透过光谱表明,Mg2+掺杂后吸收边发生蓝移,可提高ZnO薄膜的禁带宽度;I-Ⅴ特性曲线表明,正向偏压下探测器的暗电流和光照电流随外加偏压呈线性增长,但光照电流与暗电流的差别较大.

Preparation of MgxZn1-xO Thin Films by Sol-gel Technique and Study on Its Properties

Zinc oxide thin films doped with Mg2+(MgxZn1-xO) are prepared on quartz glass substrates by the solgel method.The influence of Mg2+ dopants on the microstructure and optical property of MgxZn1-xO thin films is investigated in detail.The model Mg0.1 Zn0.9O ultraviolet detector is made by depositing A1 interdigital electrode on the surface of Mg0.1Zn0.9O film.The Ⅰ-V characteristics are measured.The XRD results indicate that the MgxZn1-xO thin films retain the wurtzite structure of ZnO when the value of x is less than 0.3.With the increase of the value of x,the lattice constant c decreases and the lattice constant a increases; Mg2+ doping restrains the growth 0f(002) face to some extent.The transmittance measurement results show that Mg2+ doping in ZnO thin films makes the absorption edge shift to the short wavelengths.The optical band gap of MgxZn1-xO thin film varies from 3.26eV to 3.73eV as Mg2+ content x increases from 0 to 0.3.TheⅠ-V characteristics show that the dark and photo current increased linearly with bias voltage,but there is great difference between them.