A manufacturing lithographic approach for high density MRAM device using KrF double mask patterning technique

摘要

MRAM, a potential candidate of next generation or "universal" memory device, has been in process development and targeted for production. This high density non-volatile memory has a fast <20ns read/write cycle and unlimited endurance. Wordline layer is important for writing. Using KrF tool capability only, this "line & contact hole" wordline pattern must meet the challenge of aggressive pitch size shrinkage and process margin requirements in order to deliver reliable writing efficiency. Thus, appropriate process integration schemes demonstrating single exposure, double exposure and double patterning are compared. A comprehensive study from mask layout simulation and its cost to litho OL/CD process window experimental data analysis will be presented to achieve potential high yield manufacturing goal of the critical wordline design and process integration.