通过硬烘降低SU-8侧壁粗糙度  

SU-8 Side Wall Roughness Reduction Through Hard Baking

作　　者：田苗 张笛 瞿敏妮 毛海平 乌李瑛 孔路瑶 Tian Miao;Zhang Di;Qu Minni;Mao Haiping;Wu Liying;Kong Luyao(Center for Advanced Electronic Materials and Devices,School of Electronic Information and Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学,电子信息与电气工程学院,先进电子材料与器件平台,上海200240

出　　处：《微纳电子技术》2020年第12期1028-1032,共5页Micronanoelectronic Technology

摘　　要：当以SU-8光刻胶作为模具制备大深宽比结构或者直接用SU-8作为结构材料时,都难以避免地受到粗糙侧壁的影响。而随着器件性能的提高,这一问题越来越影响到SU-8的应用。通过使用硬烘的方法来改善SU-8胶的侧壁粗糙度。通过调整硬烘温度和时间,成功地将SU-8胶侧壁的均方根粗糙度从185.9 nm降低到了7.6 nm。通过光学金相显微镜观察SU-8侧壁的形貌,证实了随着硬烘温度和时间的增加,侧壁波纹逐渐消除。原子力显微镜(AFM)表征进一步验证了粗糙度的下降。最后以微波、毫米波、太赫兹波等高频信号在铜波导中传播的情形为例,讨论了粗糙度对传输阻抗的影响,证明了粗糙度降低的意义。When the SU-8 photoresist is used as mould to prepare the large depth-width ratio structure,or is directly used as a structural material,the effect of the rough side wall is inevitable.With the improvement of device performances,this problem affects the SU-8 application more and more.The hard baking method was used to improve side wall surface roughness of the SU-8.By adjusting the hard baking temperature and time,the root mean square roughness of the SU-8 side wall was successfully reduced from185.9 nm to 7.6 nm.The morphology of the Su-8 side wall was observed through optical metallographic microscope.It is confirmed that with the increasees of the temperature and time of hard baking,the side wall stripes are gradually eliminated.The roughness reduction was further verified by atomic force microscope(AFM)characterization.Finally,the transmission of high frequency signals such as microwave,millimeter wave and terahertz wave through Cu waveguides was taken as an example to discuss the effect of the roughness on transmission impedance and prove the significance of roughness reduction.

关 键 词：SU-8胶 硬烘 粗糙度 大深宽比 铜波导 侧壁 波纹 

分 类 号：TN305[电子电信—物理电子学]