Application Areas
Wafer Level MEMS Packaging:
Unity® Sacrificial Materials are extremely useful in making completely encapsulated airgaps for WLMP. They can be applied using a standard spin coat process and either photo-defined or dry etch patterned. A suitable overcoat material can be applied. Then the Unity® Sacrificial
Material can be completely decomposed by treating the wafer with a simple thermal process. This ability of Unity® Sacrificial Materials to decompose even through unvented, solid overcoats makes them ideally suited for WLMP.
Microstructure Fabrication Materials: Some Unity® Sacrificial Materials are well-suited to making 3-D microstructures. They can be applied via standard spin coat process and photo-imaged. Multiple coatings can be applied allowing for the fabrication of complex structures. These structures can be overcoated and the Unity® Sacrificial Material decomposed leaving a free-standing microstructure.
Protective Coatings: Photo-definable Unity® Sacrificial Materials can be applied to the wafer’s front or back side using a standard spin coat process and patterned to provide clear dicing streets and bond pad or thru-via areas without the need for a photoresist or an etching process. This protective coating can be removed after the processing is complete by a simple thermal process with little material residue, and therefore, no further clean-up.
Temporary Wafer Bonding: Unity® Sacrificial Materials for Temporary Wafer Bonding can be applied using a standard spin coat process, soft-baked to dry or pre-cure the layer and then used to bond the wafer to a carrier in a thermal compression bonder. Wafer release after processing is by a simple thermal process with little material residue, and therefore, no further clean-up. Low temperature grades have been developed for processes with thermal limitations and higher temperature grades have been developed for processes that require stability to higher temperatures, with subsequent de-bonding at even higher temperatures. Photo-imageable materials are also available for edge-bead removal or other patterning needs.