溶胶-凝胶法制备高Mg含量Zn1-x MgxO薄膜

采用溶胶-凝胶法在石英玻璃基板上制备了ZB1-xMgxO薄膜,研究退火温度对高Mg含量Zn0.5Mg0.5O薄膜的相组成、相偏析及紫外-可见透过光谱中吸收边移动的影响,当退火温度≤500℃时,Zn0.5Mg0.5O薄膜未发生相偏析现象,且400℃退火处理制备的Zn0.5Mg0.5O薄膜的紫外-可见透过光谱中吸收边蓝移最大.因此,对于高Mg含量Zn0.5Mg0.5O薄膜,退火温度是影响Mg2+在ZnO中固溶度的关键因素,且400℃是其理想的退火温度.在此条件下研究了不同Mg含量对Zn1-xMgO(x=0～0.8)薄膜带隙调节的影响,随着Mg含量的增加,其紫外-可见透过光谱中紫外光区吸收边呈现规律性蓝移,光学带隙值Eg从纯ZnO的3.3 eV调节至4.2 eV.

Preparation of High Mg Content Zn1-xMgxO Thin Films by Sol-gel Method

Zn1-xMgxO thin films were prepared on quartz glass substrates by sol-gel method.The effect of annealing temperature on phase composition,phase segregation and the absorption edge shift in the UV-Vis transmission spectra of high Mg content Zn0.5Mg0.5O thin films was discussed.When the annealing temperature was not more than 500 ℃,Zn0.5 Mg0.5 O film had no phase segregation occurred,and a largest blue shift of the absorption edge of the Zn0.5Mg0.5O thin films annealed at 400 ℃ was observed.Thus,for the Zn0.5Mg0.5O films,annealing temperature is the key factor of affecting the solid solubility of Mg2+ in ZnO,and 400 ℃ is the ideal annealing temperature.Under this condition,the bandgap adjustment of Zn1-xMgxO (x =0-0.8) thin films was studied.With the increase of Mg content,the optical transmission spectra showed that the absorption edge was blue shifted regularitily,and the bandgap tuning from 3.3 eV of pure ZnO to 4.2 eV by varying the Mg content.