Japanese Journal of Applied Physics · 1978 · 52 citations · 0 references
EngineeringMaterials EngineeringOptical MaterialsOpticsPhotonicsMask DesignMask FabricationMicrofabrication MaterialsBeam SensitivityDeep Ultraviolet LithographyOptical LithographyPhotolithographic PatterningPhotolithographyPhotomask FabricationSensitivitySubmicron Pattern Replication
Methacrylates PMMA, P(MMA-MA)and FBM can be satisfactorily used as photoresist. FBM has the sensitivity 7 times higher than the PMMA standard developing system. PGMA and P(GMA-EA) have the positive working behaviors. The chrome-on-quartz substrate mask is suitable as a photomask. A Xe–Hg short arc lamp and a Hg long arc lamp are excellent deep-uv sources. Using a collimated exposure system with the 110 mm beam diameter composed of a 600 W Xe–Hg arc lamp, an ellipsoidal reflector and an optical integrator, the required expousre time for PMMA with 1 µm thickness is about 1.5 min. High quality submicron patterns having an aspect ratio of 5 can be replicated on PMMA and P(MMA-MA) by contact printing. A pattern consisting of 1 µm lines is printed on FBM 0.8 µm thick. In the proximity printing, high quality 2 µm patterns can be replicated on PMMA 0.7 µm thick with 20 µm spacings when the beam collimating angle is 2°.