High Topography Polyimide CMP Process

Abstract:

This paper reports a process of filling and planarization of microstructures for MEMS and wafer level packaging application. In this work, cavities of 5-10mm depth and 20-100mm in length/width are filled using multiple coatings of polyimide with kinematic viscosities in the range of 20-130St. Such filling results in overfilling of polyimide in the range of 2 to 10mm due to variation in density and geometry of microstructure. A chemical and mechanical polishing (CMP) based planarization process, to achieve polyimide thickness variation <0.2mm in varied structures is presented.

• Periodical: Advanced Materials Research (Volume 254)
• Pages: 107-110
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.254.107
• Online since: May 2011
• Authors: Ying Jun Mao, Gim Guan Chen, Ramana Murthy, Swee Kiat Eugene Tan
• Keywords: CMP Process, High Topography, Polyimide

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