Decomposable and Template Polymers: Fundamentals and Applications

Abstract

Polymers can be used as temporary place holders in the fabrication of embedded air gaps in a variety of electronic devices. Embedded air cavities can provide the lowest dielectric constant and loss for electrical insulation, mechanical compliance in devices where low-force deformations are desirable, and can temporarily protect movable parts during processing. Several families of polymers have been used as sacrificial, templating polymers including polycarbonates, polynorbornenes (PNBs), and polyaldehydes. The families can be distinguished by chemical structure and decomposition temperature. The decomposition temperature ranges from over 400 °C to below room temperature in the case of low ceiling temperature polymers. Overcoat materials include silicon dioxide, polyimides, epoxy, and bis-benzocyclobutene (BCB). The methods of air-gap fabrication are discussed. Finally, the use of photoactive compounds in the patterning of the sacrificial polymers is reviewed.

Theoretical Study on Decomposition Mechanism of Insulating Epoxy Resin Cured by Anhydride

“…Anhydride-cured epoxy resins are widely used as solid insulators in large electrical equipment because of their excellent resistance to leakage traces [ 1 ]. Despite these features, these resins are prone to defects such as grooves and gas gaps during their manufacture, transportation, and operation because of electric, heat, and mechanical stresses.…”

Stable, High‐Molecular‐Weight Poly(phthalaldehyde)

“…Thermodynamically unstable polymers have emerged in applications where a catalytic response to a small trigger is necessary or environmental degradation is desired . The amplified degradation in macro‐scale plastics offers a solution to a variety of problems including drug delivery, dry‐developing photoresists, and transient electronics . The catalytic response to a stimulus allows the polymer to efficiently and rapidly decompose into its original monomer or other small molecule products.…”

Future manufacturing and remanufacturing of polymeric materials

“…due to its slow hydrolysis in tissue. Certain polymers made from ethylenically unsaturated monomers (those with a low ceiling temperature) will depolymerize in response to moderate increases in temperature . Polymers made from natural products will tend toward biodegradability (for better and worse).…”