氧化锌脱膜和激光刻蚀制备亚微米自支撑聚酰亚胺薄膜及其性能

探讨小于1 μm自支撑聚酰亚胺薄膜的制备及其性能。以稀盐酸为腐蚀剂, 对涂于氧化锌衬底上的聚酰胺酸薄膜进行剥离, 经热亚胺转化为聚酰亚胺薄膜, 再用准分子激光对其刻蚀减薄。采用原子力显微镜、傅里叶变换红外光谱仪和分光光度计对薄膜的微观结构和光谱性能进行了表征。结果表明, 以室温下溅射的氧化锌薄膜为脱膜剂, 制备了厚度约950 nm的自支撑薄膜, 而激光刻蚀使聚酰亚胺薄膜厚度减薄至150 nm。厚度分别为950和150 nm薄膜的红外谱中均出现了聚酰亚胺特征吸收峰(1775、1720、1380和725 cm^-1), 且两者在400~2500 nm范围的平均透过率分别为80.3% 和83.5%。

Preparation and Properties of Submicron Free-standing Polyimide Thin Film Using ZnO Demoulding and Laser Ablation

A process for the preparation of free-standing polyimide (PI) thin films of less than 1 μm thickness was proposed and the property of the films was analyzed. In this process, a polyamic acid (PAA) thin film of 1 μm thickness was first prepared on a ZnO coated substrate and then released using diluted hydrochloride acid. The PAA film was reattached to the substrate and treated thermally to create a polyimide thin film. The thickness of the PI film was reduced using excimer laser ablation. The surface morphology and the spectral characteristics of the polyimide film were investigated using atomic force microscope, Fourier transform infrared spectroscope and spectrophotometry. Results showed that ZnO thin films sputtered at room temperature served as a good release agent for preparing free-standing polyimide films with thickness more than 950 nm. The thickness of the PI films could be reduced to as thin as 150 nm by excimer laser ablation. In the wavelength range from 400 nm to 2500 nm, the average transmittance increased from 80.3% to 83.5% when the thickness of the polyimide film decreased from 950 nm to 150 nm.