publication . Article . 2018

Wafer-Level Packaging Method for RF MEMS Applications Using Pre-Patterned BCB Polymer

Zhuhao Gong; Yulong Zhang; Xin Guo; Zewen Liu;
Open Access English
  • Published: 01 Feb 2018 Journal: Micromachines, volume 9, issue 3 (eissn: 2072-666X, Copyright policy)
  • Publisher: MDPI
Abstract
A radio-frequency micro-electro-mechanical system (RF MEMS) wafer-level packaging (WLP) method using pre-patterned benzo-cyclo-butene (BCB) polymers with a high-resistivity silicon cap is proposed to achieve high bonding quality and excellent RF performance. In this process, the BCB polymer was pre-defined to form the sealing ring and bonding layer by the spin-coating and patterning of photosensitive BCB before the cavity formation. During anisotropic wet etching of the silicon wafer to generate the housing cavity, the BCB sealing ring was protected by a sputtered Cr/Au (chromium/gold) layer. The average measured thickness of the BCB layer was 5.9 μm. In contras...
Persistent Identifiers
Subjects
free text keywords: Article, wafer-level packaging, adhesive bonding, photosensitive BCB, RF MEMS, Control and Systems Engineering, Mechanical Engineering, Electrical and Electronic Engineering, Materials science, Microelectromechanical systems, Etching (microfabrication), Coplanar waveguide, Optoelectronics, business.industry, business, Wafer, Insertion loss, Silicon, chemistry.chemical_element, chemistry, lcsh:Mechanical engineering and machinery, lcsh:TJ1-1570
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