In this paper, a method is presented to detect the different phases of epoxy cross‐linking process and the subsurface structures of SU‐8 thin films by atomic force acoustic microscopy (AFAM). The AFAM imaging of SU‐8 thin films was investigated under different exposure and bake conditions. Optimized conditions were obtained for the cross‐linking of SU‐8 thin film at the exposure does of eight laser pulses with the laser fluence 10 mJ cm–2 per pulse and the post exposure bake (PEB) time at 90 s. The subsurface structures of undeveloped SU‐8 thin films were visible in the AFAM images. This method provides an effective and low‐cost way for the determination of different phases of epoxy cross‐linking process in nanostructured compounds, for the non‐destructive testing of subsurface defects, and for the evaluation of the quality of patterned structures.

中文翻译：

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SU-8光刻胶交联过程的原子力声学显微镜研究

在本文中，提出了一种通过原子力声学显微镜（AFAM）检测环氧树脂交联过程的不同阶段和 SU-8 薄膜的亚表面结构的方法。在不同的曝光和烘烤条件下研究了 SU-8 薄膜的 AFAM 成像。在 8 个激光脉冲的曝光剂量下获得 SU-8 薄膜交联的优化条件，每个脉冲的激光能量密度为 10 mJ cm-2，曝光后烘烤 (PEB) 时间为 90 秒。在 AFAM 图像中可以看到未显影的 SU-8 薄膜的亚表面结构。该方法为确定纳米结构化合物中环氧交联过程的不同阶段、亚表面缺陷的无损检测以及评估图案结构的质量提供了一种有效且低成本的方法。