Laser direct exposure with AR-P 3540

In addition to a structuring with photomasks which is frequently used in lithography, is it also possible to write the structures directly, i.e. without masks, with laser beams. The most commonly used wavelength for this purpose is the 405 nm line.

By merging classical mask-based exposure methods (contact, proximity and projection exposure) with modern maskless lithography (laser and electron beam exposure), mix & match technologies are possible which combine the high throughput of mask technology with a high resolution in the sub-µm range (laser).

This technology is in particular aimed at increasing the user’s efficiency of exposure techniques, in particular for MEMS and sensor technology processes.

In analogy to well-known photolithographic structuring procedures (see Resist-Wiki General Basic Chemistry), AR-P 3540 is chemically modified using a controlled laser beam and dissolved in the subsequent development. In test series, new fields of application for AR-P 3540 in maskless lithography were investigated and evaluated.

Good results are presented in the following figures – resolutions of significantly less than 1.0 µm were achieved.

Fig. 1 Resolved structures (bars) <1.0 µm in AR-P 3540

Fig. 2 Resolved structures (holes) <1.0 µm in AR-P 3540

According to information provided by Klaus-Dieter Preuß – development engineer at the CiS Research Institute for Micro Sensors and Photovoltaics GmbH and Dr. Axel Weidner – managing director of the ML Microlithography Service GmbH Jena (see also AR NEWS 28. issue)