Tverdokhleb Nina, Loebner Sarah, Yadav Bharti, Santer Svetlana, Saphiannikova Marina
Institute Theory of Polymers, Leibniz Institute of Polymer Research Dresden, 01069 Dresden, Germany.
Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany.
Polymers (Basel). 2023 Jan 16;15(2):463. doi: 10.3390/polym15020463.
We report on solving of two intriguing issues concerning the inscription of surface relief gratings within azopolymer thin films under irradiation with SS, PP and RL interference patterns. For this, we utilize the orientation approach and viscoplastic modeling in combination with experimental results, where the change in surface topography is acquired in situ during irradiation with modulated light. First, the initial orientation state of polymer backbones is proved to be responsible for the contradictory experimental reports on the efficiency of the SS interference pattern. Different orientation states can influence not only the phase of SS grating but also its height, which is experimentally confirmed by using special pretreatments. Second, the faster growth of gratings inscribed by the RL interference pattern is shown to be promoted by a weak photosoftening effect. Overall, the modeled results are in good agreement with the order of relative growth efficiency: RL-PP-SS.
我们报告了关于在用单次曝光（SS）、多次曝光（PP）和旋转光阑（RL）干涉图案照射时，在偶氮聚合物薄膜内刻写表面起伏光栅所涉及的两个有趣问题的解决情况。为此，我们将取向方法和粘塑性模型与实验结果相结合，其中在调制光照射期间原位获取表面形貌的变化。首先，事实证明聚合物主链的初始取向状态是关于SS干涉图案效率的相互矛盾的实验报告的原因。不同的取向状态不仅会影响SS光栅的相位，还会影响其高度，这通过特殊预处理得到了实验证实。其次，RL干涉图案刻写的光栅更快的生长被证明是由弱光软化效应促进的。总体而言，模拟结果与相对生长效率顺序：RL - PP - SS高度吻合。
