Development of novel technique for patterning of ceramic thin films based on Benard convection

我们认为Benard-Marangoni对流诱导的自发图案形成是一种新的溶胶-凝胶法陶瓷薄膜的图案化过程。采用浸渍提拉法制备的二氧化硅薄膜表面自发形成了胞状微图案，表面图案平行于衬底退缩方向呈线性排列。这种高度有序的微图形是通过Benard-Marangoni对流和涂层溶液在浸渍镀膜过程中在衬底上的单向流动获得的。我们发现，随着镀膜温度和镀液表面张力的增加，由Benard-Marangoni对流引起的胞状图案的尺寸增大。此外，随着衬底抽拉速度的降低，观察到了毛细作用力诱导的新图案的形成。这些结果有利于发展由溶剂挥发引发的新型自组织。

We suggested the spontaneous pattern formation induced by Benard-Marangoni convection as a novel patterning process of sol-gel-derived ceramic films. Cell-like micropatterns were spontaneously formed on the surface of silica films prepared via dip-coating process, where the surface patterns were linearly arranged parallel to the substrate withdrawal direction. Such highly-ordered micropatterns were achieved by Benard-Marangoni convection and the unidirectional flow of the coating solution on the substrate during dip-coating. We found that the size of the cell-like patterns induced by Benard-Marangoni convection increased with increasing coating temperature and surface tension of coating solutions. Moreover, novel pattern formation induced by capillary force was observed with decreasing substrate withdrawal speeds. These results are beneficial for the development of novel self-organization triggered by solvent evaporation.