Structuring by ablation of the resist materials

The basic principle of laser ablation is that laser irradiation of a certain wavelength introduces so much energy into the resist material which is modified for ablation that the resist polymer is destroyed and then vaporizes as low molecular weight fragments.

Bleachable resists

The basic idea behind dyed resists developed within the scope of the Photoenco project (June 2016 – May 2019) was that dyes are mixed into the polymer matrix of the resist which then either change their colour or become colourless upon irradiation.

Fluorescent resist structures with photoresists

Photoresists can also be used to incorporate fluorescent dyes. Particularly negative-tone photoresists are of interest in this regard, since the use of selected fluorescent dyes allows defining an adjustable emission in variable wavelength ranges. Resist layers with violet, blue, yellow, orange, or red fluorescence were produced by embedding the respective dyes into the negative-working Atlas 46 S resist.

Negative CAR PMMA resist SX AR-N 4810/1

The principle of chemical amplification could successfully be transferred to PMMA polymers. The new special resist SX AR-N 4810/1 is a chemically amplified photoresist based on PMMA that can be developed anhydrously with organic solvents – a crucial property in the case of moisture-sensitive substrates.

Atlas 46 for nanoimprint lithography

The new development Atlas 46 could also be successfully used for nanoimprinting (University of Wuppertal, working group of Prof. Scheer). In a first step, nanostructures were produced with the negative-working resist

Coloured negative photoresists

Allresist now also offers colored negative resists with the designation SX AR-N 8500. The difference to FUJIFILM resists is that only dyes and no pigments are dissolved in the resists. This allows to achieve a high resolution and high edge sharpness.

CAR 44 on copper

If negative photoresist CAR 44 (AR-N 4400) is directly used on copper or copper-containing substrates, the following points must be observed.

Surface imaging resist system SX AR-N 7100 – silylable photoresist

The negative photoresist experimental sample SX AR-N 7100 is a surface imaging and dry developable system. With this system, structures can be transferred into thick resist layers by means of plasma etching.

Alkali-stable positive resist obtained after treatment with HMDS

A large variety of applications include a wet-chemical etching step which very often involves highly alkaline etching baths.

Adaptable two-layer resist AR-BR 5460 for variable lift-off structures

Bottom resist AR-BR 5460 has already been used for a decade in combination with positive (e.g. AR-P 3510) or negative resists (e.g. AR-N 4340) for a large variety of lift-off applications.