There are many materials that can be modified by a heated probe tip. But for the NanoFrazor technology, the choice of resist material plays a crucial role.
We recommend to use polyphthalaldehyde as a standard resist due to its remarkable properties and its wide acceptance in the community. PPA is a so-called self-amplified unzip polymer which instantaneously decomposes into its volatile monomers upon an external trigger like a heat pulse. The unzipping is an endothermic reaction confining the spread of heat in the resist, enabling high-resolution patterning. The decomposition products evaporate immediately without re-deposition on the substrate. Patterned PPA does not need wet chemical development and due to its high glass-transition temperature, it can directly be used as an etch-mask with high mechanical stability.
SwissLitho has a strong expertise with transfer layers for pattern transfer using PPA. Furthermore, within the framework of the Eurostars project: PPA-Litho we are actively researching novel PPA variants for specific applications.