Modelling and compensating proximity effects in massively parallelized multiphoton photoplotting

Multi-photon polymerization is widely recognised as a promising approach for the fabrication of fully 3D micro or nano-metric structures. The ability to write such structures at high plot rates would open new frontiers in many fields s uch a s h ealth, o ptical m icro-devices, s ecurity h olograms e tc. P arallelization o f t he fabrication process increases fabrication speed. In a first p arallelization a pproach w e u se a s hort p ulsed l aser (picoseconds or femtoseconds) with a diffractive o ptical e lement w hich a llows s imultaneous f abrication w ith h undreds write spots, decreasing the overall fabrication time. In a second approach, a 1920 x 1080 pixel spatial light modulator is imaged into an ultra-sensitive resist using continuous wave laser. However, massive parallelization can lead to unwanted fabrication artefacts. Light field overlapping i n o ut-of-focus p lanes a nd p roximity e ffects ar e currently major issues limiting the performance of parallel micro fabrication processes due to the undesired polymerisation that results. We will present our latest photo-chemical process digital simulation results and show how they are enabling us to develop and apply precompensation techniques to the plot data to fabricate structures with a smaller Z-extent and/or circumvent proximity effects.