Industrial Maskless Aligner: New levels of flexibility in lithography

Inhalt:
Maskless lithography has a flexibility advantage over traditional mask-based production methods with mask aligner or a stepper. This advantage comes at the cost of reduced throughput as a spatial light modulator (the “dynamic mask”) contains fewer data than a full mask or reticle. One method of increasing throughput is to simultaneously expose the substrate with multiple exposure modules. A multi-module exposure should have the same quality as a single module exposure, so the stitching boundary where the two exposure segments meet must be correctly aligned. The modules comprise optical compensations, designed to match the range of misalignment expected for thermal drift. There are additional sources of misalignment, mainly scaling and rotation of a first layer pattern. The data conversion was therefore extended to resegment the exposure data to take this into account working in tandem with the optical compensations.