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
Positive/Negative/Image Reversal Chemical Stability Thermal Stability Optical Properties Solvent The Resin The Photo Active Compound
The softening point of AZ® and TI positive- and image reversal resists depends on the resist familty, the remaining solvent concentration, and - in case of image reversal resists - on the image reversal bake temperature. typical values for the softening point are approx. 110-135°C which can further be increased by UV-hardening. Exceeding the softening temperature causes roundening of the (developed) resist structures.

From approx. 120°C on, photoresists start to react with athmospheric oxygen appearing in a yellowish/brownish colouring accompanied by an embrittling with crackle formation towards higher temperatures. Dependant on the subsequent processing, baking steps up to 170-180°C may be necessary to increase the thermal or chemical stability.

The aqueous alkaline developable AZ® nLOF 2000 negative resist family reveals a very high thermal stability against roundening in the crosslinked state (resist profile stable up to 250°C and more).
 Softbake and Remaining Solvent Concentration  Image Reversal Bake and Thermal Stability e-Mail Anfrage Image reversal resists e-Mail Anfrage AZ nLOF 2000 negative resists
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)