基于斜光刻技术的SU-8胶三维微阵列结构制备

Fabrication of 3D SU-8 Photoresist Microarrays via Inclined Uitraviolet Lithography

利用斜光刻技术替代传统的直光刻技术在相同底面积的基础上增大微阵列比表面积制备了高比表面积三维微阵列结构,。首先,利用MATLAB仿真对微阵列排布方式进行分析,确定最佳单个柱体宽度及阵列间距。实验中,采用两次甩胶法将SU-8光刻胶均匀旋涂在2寸硅基底上,甩胶转速设为1500 r/min,旋涂时间设为35 s;分别置于65℃烘台上保持20 min和95℃烘台上保持70 min进行两次前烘处理;随后进行双向斜曝光,微柱宽度为20μm,阵列间距为30μm,光刻角度为20°。最后,再通过高低温后烘处理并显影30 min成功制备出了结构稳定的"X"型三维微阵列结构。

To increase the specific surface area of three-dimensional（ 3D） microarrays,we proposed a novel method using the inclined UV lithography of the negative thick SU-8 photoresist instead of the traditional lithography. Firstly, we studied the effects of the array arrangement on the surface area of the SU-8photoresist-based microarrays with MATLAB simulation,and determined the best parameters of the width of single micro-column and the space of the microarrays. During the fabrication processes,photoresist spinning was firstly performed twice to deposit a thick SU-8 photoresist layer on 2-inch silicon substrate,while the rotational speed and time were respectively set to 1500 r / min and 35 s. Then,the samples were respectively placed on a baking plate for 20 min at 65℃ and 70 min at 95℃ for pre-baking. The next step was the inclined UV lithography from both sides,in which the width of micro pillars was 20 μm,the space between the pillars was 30 μm and the lithography angle was 20°. Finally,we successfully fabricated the stable ＂ X ＂ type microarray with high specific surface after the high-low temperature post exposure baking and 30 min developing.