Lithographic performance of resist ma-N 1402 in an e-beam/i-line stepper intra-level mix and match approach

In this paper, we describe a lithographic technique of exposing complex patterns with an advanced resist processing that connects the high resolution of electron beam lithography and the fast exposure of optical i-line stepper lithography via an Intra Level Mix and Match (ILM&M) approach. The key element of our approach is that we use two successive exposures on one single resist layer directly followed by a single resist development. Process and resist characterization of negative tone resist ma-N 1402 as well as a resolution study for each lithographic tools involved. Lithographic performance of negative tone resist ma-N 1402 has shown structures with dimensions of 55 nm with 300 nm pitch for e-beam lithography (VISTEC SB254, shaped beam) and 350 nm structures for i-line stepper (Nikon NSR 2205i11D). Resist footing problem in structures exposed by i-line stepper is solved by introducing a 200 nm thick bottom antireflective coating AZ BARLI II in ILM&M resist processing sequence. A general processing recipe for electron beam/i-line stepper ILM&M with negative tone resist ma-N 1402 is successfully developed and patterns with different dimensions ranging from sub 100 nm to µm scale were reproducibly fabricated on the same resist layer.