Photoresist Processing Trouble-Shooting Etchants and Solvents
Photoresists Ancillaries Storage/Handling/Ageing Substrate Pre-Treatment and Coating Baking Steps Exposure Development Coating and Lift-off Etching and Stripping
Wet-Chemical Etching (Adhesion and Under-Etching) Dry-Etching Stripping / Removal
Heat development during etching might soften the resist used as etch mask with rounded resist edges transferred into the substrate as a consequence. In this case, reducing the remaining solvent concentration (=reducing the resist softening point) in the resist by a prolonged softbake, or/and UV-curing might help. It"s always a good choice to use resists with high intrinsic thermal stability (e.g. AZ® 701MiR or image reversal resists like AZ® 5214E, TI 09XR, TI 35ES with increased thermal stability in the reversal mode), or AZ® nLOF negative resist.

In plasma, UV radiation with spectral lines within the absorption range (g-, h-, and i-line) of photo resists might expose the resist during etching causing N2 at a high rate forming bubbles and foaming at elevated temperatures. In this case, a flood exposure (without mask, with subsequent delay to outgas N2) or/and the usage of image reversal resists in the reversal mode (TI 09XR, TI 35ES) will help. Also a good alternative is the usage of resists with a high thermal stability and without gas formation during exposure like AZ® nLOF 2000 series, which can be developed in aqueous alkaline solutions, and removed in O-plasma or, alternatively, in organic solvents such as acetone or NMP.
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MicroChemicals« - All you need for microstructuring with short lead times also in small sales volumes:

Photoresists (positive, negative, image reversal, thin and thick resists, spray resists, protective coating ...)
Ancillaries ( developers, thinner, adhesion promoter such as HMDS, remover)
Etchants (acids and the ready-to-use etching mixtures aluminium etch, chromium etch, gold etch und silicon etch)
Solvents (acetone, isopropyl alcohol, MEK ... in VLSI and ULSI quality)