H_2O_2对溶液法制备a-IGZO薄膜光学特性的影响

基于溶液旋涂法和高压退火工艺制备了a-IGZO薄膜。采用椭圆偏振光谱分析仪以及原子力显微镜研究和分析了H_2O_2对薄膜的表面结构和光学特性的影响。实验结果表明,a-IGZO前驱液中不含H_2O_2的薄膜,退火温度从220℃升高到300℃,薄膜的光学带隙从3.03增加到3.29,而膜表面粗糙层由20.69nm降至4.68nm。在同样的高压退火条件处理下,与前驱液中没加入H_2O_2的薄膜相比,折射率显著增加并明显的降低了薄膜表面粗糙度。退火温度在300℃时,薄膜的光学带隙由3.29eV增大到3.34eV,表面粗糙层由4.68nm减少到2.89nm。因此,H_2O_2可以在相对低温条件下有效降低薄膜内部的有机物残留及微缺陷,形成更加致密的a-IGZO薄膜。证明了利用H_2O_2能够有效降低溶液法制备aIGZO薄膜所需的退火温度。

Influence of hydrogen peroxide on optical properties of a-IGZO thin films by solution Process

The a-IGZO films were fabricated by solution method and high-pressure annealing process,and the effects of H₂O₂ on microstructural and optical properties of the a-IGZO films were studied by spectroscopic ellipsometry and atomic force microscope (AFM). Results indicated that when the annealing temperature was increased from 220℃ to 300℃,the optical band gap of the film was increased from 3.03 eV to 3.29 eV, the roughness was decreased from 20.69 nm to 4.68 nm.Compared to the film without H₂O₂,the refractive of the film with H₂O₂ was increased and the roughness was decreased obviously under the same high-pressure annealing process, the optical band gap of the film was increased from 3.29 eV to 3.34 eV, but the surface roughness was decreased from 4.68 nm to 2.89 nm at 300℃.Therefore,employing H₂O₂ in the solution could effectively minimize organic chemical residues and pores at lower temperatures,as well as form more dense a-IGZO film. All experiment results indicated that H₂O₂ could decrease the temperature of treatment when depositing a-IGZO films by solution method.