以聚乙烯醇(PVA)水溶液为成膜溶液,硅片为成膜基板,采用浸渍-提拉法在硅片上制备了PVA纳米膜。通过对PVA溶液表面张力和黏度的测量,并结合高精度椭圆偏振光谱仪、透反射偏光显微镜和原子力显微镜对所制备PVA纳米膜的厚度和表面形貌进行了测定和分析。结果表明,在高的提拉速率下,纳米膜的膜厚由提拉速率控制,符合Landau-Levich理论提出的标度关系;在低的提拉速率下,膜厚由溶剂挥发速率控制,与提拉速率无关。
Poly(vinyl alcohol) nanofilm was dip-coated on the silicon wafer,with PVA-water solution as film-forming solution,and the silicon water as substrate.The surface tension and viscosity of PVA-water solution were measured by surface tension meter and Ubbelohode viscometer,respectively.The thickness and surface morphology of PVA were characterized by ellipsometer,optical microscope and AFM,respectively.The results showed that the thickness of PVA nanofilm was controlled by pulling rate at the high rate regime,which was in accordance with Landau-Levich theory.While at slower pulling rate,independent of pulling rate,the thickness was controlled by solvent evaporation.
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基金资助
国家自然科学基金(21204011);中央高校基本科研业务费专项基金资助
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