水溶性丙烯酸酯类感光干膜的制备及其性能研究

Preparation and Performance of UV-curing Waterborne Dry Film Photoresist Based on Acrylic Resins

用溶液聚合法合成了水溶性丙烯酸树脂,并以该树脂为成膜物质制备了水溶性感光干膜。傅立叶-红外光谱和1 HNMR分析表明,丙烯酸树脂中不含C=C不饱和双键,基本不参与紫外光固化反应。感光干膜性能测试表明,干膜中丙烯酸树脂的酸值及重均分子量会影响干膜的解析度和附着力等性能。进一步的研究表明,曝光能量、感光级数和显影时间也会直接影响干膜的性能。以30μm厚度干膜Ⅱ为例,为获得较好的性能,丙烯酸树脂中甲基丙烯酸含量范围为21.5%-23.8%,重均分子量范围为6.00×10^4-7.54×10^4,曝光能量设定40-60mJ/cm^2,感光级数为18-23/41ST,显影时间40-50s,在此条件下,干膜的解析度可以达到30μm,附着力为20μm,干膜线路的侧边形貌和尺寸稳定性良好。此外,感光干膜中丙烯酸酯的比例和种类也会影响干膜的各方面性能,通过调节干膜中各组分含量的比例可以优化干膜性能。

Water-soluble acrylic resins were synthesized by radical polymerization, which were used to prepare UV-curing waterborne dry film photoresist. FT-IR showed that no C=C bonds existed in acrylic resins, indicated that the resins didn＇t take part in the UV-curing reaction. Test results exhibited that not only acid value and Weight-average Molecular Weight （Mw） of acrylic resins, but also exposure energy and developing time influenced the performance of dry film photoresist obviously. Take II dry film photoresist for example, the optimal conditions were as follows. When the thickness of dry film photoresist was 30 micron, acid value ranged from 140-154, Mw was in the range of 6.00 × 10^4 -7. 54 × 10^4. Exposure energy and developing time should be 40-60 mJ/cm^2 and 40450 s, respectively, in these conditions, good sidewall geometry and high resolution （30 μm） were obtained.