中国物理B ›› 2018, Vol. 27 ›› Issue (6): 68104-068104.doi: 10.1088/1674-1056/27/6/068104

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Effect of substrate curvature on thickness distribution of polydimethylsiloxane thin film in spin coating process

Ying Yan(闫英), Ping Zhou(周平), Shang-Xiong Zhang(张尚雄), Xiao-Guang Guo(郭晓光), Dong-Ming Guo(郭东明)   

  1. Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
  • 收稿日期:2018-02-23 修回日期:2018-04-03 出版日期:2018-06-05 发布日期:2018-06-05
  • 通讯作者: Ying Yan E-mail:yanying@dlut.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos.51605079 and 51475076),the Science Fund for Creative Research Groups of the National Natural Science Foundation of China (Grant No.51621064),and the China Postdoctoral Science Foundation (Grant No.2016M591424).

Effect of substrate curvature on thickness distribution of polydimethylsiloxane thin film in spin coating process

Ying Yan(闫英), Ping Zhou(周平), Shang-Xiong Zhang(张尚雄), Xiao-Guang Guo(郭晓光), Dong-Ming Guo(郭东明)   

  1. Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
  • Received:2018-02-23 Revised:2018-04-03 Online:2018-06-05 Published:2018-06-05
  • Contact: Ying Yan E-mail:yanying@dlut.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos.51605079 and 51475076),the Science Fund for Creative Research Groups of the National Natural Science Foundation of China (Grant No.51621064),and the China Postdoctoral Science Foundation (Grant No.2016M591424).

摘要: The polymer spin coating is critical in flexible electronic manufaction and micro-electro-mechanical system (MEMS) devices due to its simple operation, and uniformly coated layers. Some researchers focus on the effects of spin coating parameters such as wafer rotating speed, the viscosity of the coating liquid and solvent evaporation on final film thickness. In this work, the influence of substrate curvature on film thickness distribution is considered. A new parameter which represents the edge bead effect ratio (re) is proposed to investigate the influence factor of edge bead effect. Several operation parameters including the curvature of the substrate and the wafer-spin speed are taken into account to study the effects on the film thickness uniformity and edge-bead ratio. The morphologies and film thickness values of the spin-coated PDMS films under various substrate curvatures and coating speeds are measured with laser confocal microscopy. According to the results, both the convex and concave substrate will help to reduce the edge-bead effect significantly and thin film with better surface morphology can be obtained at high spin speed. Additionally, the relationship between the edge-bead ratio and the thin film thickness is like parabolic curve instead of linear dependence. This work may contribute to the mass production of flexible electronic devices.

关键词: spin coating, non-planar substrate, film thickness distribution, edge-bead effect

Abstract: The polymer spin coating is critical in flexible electronic manufaction and micro-electro-mechanical system (MEMS) devices due to its simple operation, and uniformly coated layers. Some researchers focus on the effects of spin coating parameters such as wafer rotating speed, the viscosity of the coating liquid and solvent evaporation on final film thickness. In this work, the influence of substrate curvature on film thickness distribution is considered. A new parameter which represents the edge bead effect ratio (re) is proposed to investigate the influence factor of edge bead effect. Several operation parameters including the curvature of the substrate and the wafer-spin speed are taken into account to study the effects on the film thickness uniformity and edge-bead ratio. The morphologies and film thickness values of the spin-coated PDMS films under various substrate curvatures and coating speeds are measured with laser confocal microscopy. According to the results, both the convex and concave substrate will help to reduce the edge-bead effect significantly and thin film with better surface morphology can be obtained at high spin speed. Additionally, the relationship between the edge-bead ratio and the thin film thickness is like parabolic curve instead of linear dependence. This work may contribute to the mass production of flexible electronic devices.

Key words: spin coating, non-planar substrate, film thickness distribution, edge-bead effect

中图分类号:  (Methods of deposition of films and coatings; film growth and epitaxy)

  • 81.15.-z
68.15.+e (Liquid thin films) 47.85.mb (Coating flows ?) 68.55.-a (Thin film structure and morphology)