Applications > MEMS

Wafer Bonding

Wafer bonding with polymer adhesives is a low cost, simple and robust fabrication process compared to alternative wafer bonding techniques. Polymer adhesive bonding is used in a number of technology spaces include micro-fluidic devices e.g. lab-on-chip applications, CMOS Image sensors, SAW devices, Wafer Level / Chip-Scale Packaging and 3D Interconnect technologies.

Advantages of using a negative tone photoepoxy for liquid adhesive wafer bonding include low bonding temperatures, compatibility with standard IC processing, high resolution features and the ability to join different substrate types.

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SU-8: Series Adhesive Advantages

• High bond strength
• Low process temperature
• Low process cost
• Photo imageable (BB or i-line)
• High Aspect Ratio (HAR) images
• Spin-coatable >100µm in a single coat
  

XP WB Adhesive Advantages

• High bond strength
• Low process temperature (<180°C)
• Void-free bonding at 150°C, 0.58MPa, 30sec.
• Low process cost
• Photo imageable (broadband or i-line)
• <20µm line/space resolution
• Non-metal (e.g. antimony) PAG

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CMOS Image Sensor Cavity. Silicon Substrate, XP WB Adhesive Walls and Glass Cap.

Cross section post wafer dicing