FeRAM technology for high density applications

Ferroelectric random access memories (FeRAMs) are new types of memories esp ecially suitable for mobile applications due to their unique properties lik e nonvolatility, small DRAM-like cell size, fast read and write as well as low voltage/low power behavior. Although standard CMOS processes can be use d for frontend and backend/metallization processes, FeRAM technology develo pment has to overcome major challenges due to new materials used for capaci tor formation. In this paper, advantages and disadvantages of different fer roelectric materials and major development issues for high density applicat ions are discussed. Results of a 0.5 mum ferroelectric process using SrBi2T a2O9 as ferroelectric layer, Pt as electrode material as well as two-layer tungsten/aluminum metallization are given as an example. Integration and re liability issues are reviewed. (C) 2001 Elsevier Science Ltd. All rights re served.