Negative polyimide photoresist
As an alternative to the positive polyimide resist (SX AR-PC 5000/82.7) which is already a polyimide in dissolved form and thus requires no curing process (see „Positive polyimide resist“) at 350-400°C , also a negative resist was developed which works according to the principle of chemical enhancement. This resist is also stable at temperatures >400°C and is accordingly very well suited for the production of high temperature-stable structures. In this case, the developer is not aqueous-alkaline, but composed of MIBK. In particular for users who process moisture-sensitive substrates, the use of a polyimide negative resist is thus recommended.
The negative resist can also be structured by electron beam lithography. For users which are not able to work under yellow light conditions, the resist can also be offered as white-light variant.
Overview of negative photoresist
Alkali-stable and solvent-stable negative resist
Chemically enhanced negative resist (Process parameters and resolution)
Chemically enhanced negative resist without cross-linking
Coloured negative photoresists
Development of thick negative resist layer
Dose-dependent structure size with negative resists
Fabrication of vertical flanks with CAR 44
Generation of undercut structures with negative resists
Negative polyimide photoresist
Negative two- layer lift-off system
NIR-laser structurable photoresists
poly(hydroxystyrene) and (hydroxystyrene-co-MMA) photoresist with high-temperature stability
Sensitive negative PMMA resist (CAR)
Sensitive negative resist for 405 nm laser direct exposure