MULTILAYER RESIST SYSTEMS.

Multi-layer resist(MLR) systems were used at least ten years ago to produce a high-thermal-stability lift of profile. There is a large variety of MLR systems using many different schemes to achieve high lithographic performance. Basically, there are a planarization layer and an imaging layer. The imaging layer is usually much thinner than the planarization layer and is delineated by exposure in an imaging equipment such as a mask aligner or a particle-beam direct-write machine.