Step-and-Repeat X-ray/Photo Hybrid Lithography for 0.3 μm Mos Devices

X-ray lithography is currently one of the most promising technologies for fabrication of VLSIs with minimum line widths below 0.5 μm. Extensive research has been conducted on the development of x-ray exposure systems, mask fabrication techniques, and x-ray resists. However, this technology has not yet been fully applied to research and development activities for device fabrication. This paper presents an application of x-ray lithography to MOS LSI fabrication. The hybrid lithography concept is proposed, which is comprised of step-and-repeat x-ray lithography combined with photo-lithography (10:1 stepper). A three-layer resist is required to fully utilize high sensitivity and resolving power features of an x-ray positive resist, FBM-G (1).