Kazutaka Tamura

New novolak-based positive EB resist, EBR-900 M-1

For the fabrication of 64 M and 256 MDRAM reticles, EB resists which have both high resolution and excellent dry etch resistance will be required. It is also particularly important to have high dry etch resistance for the manufacture of phase shift masks. For the development of traditional EB resists, organic solvents are typically used. However from the safety standpoint aqueous developers would be preferred. To meet these requirements a new positive type, aqueous developable EB resist, named EBRTM-900 M-1, has been developed. EBRTM-900 M-1 shows resolution down to 0.3 micrometers , good sensitivity, 1.6 - 5 (mu) C/cm2 (10 kV) for practical use, excellent dry etch durability same as positive optical resists, and can be developed by aqueous alkaline developers. This resist is not a chemically amplified type and shows excellent post exposure stability and no delay effect. The sensitivity of the coated film does not change in 50 days and the exposed films shows practically no change for up to 7 days in air and 2 days in vacuum. This resist has high sensitivity, not only for E-Beam, but also for argon-ion laser, 363.8 nm. Field data using production EB exposure systems will be presented. The lithographic properties using a CORE- 2564 scanned laser system, are also studied.