Integration aspects of advanced ferroelectric thin-film memories

Abstract

This chapter discusses the highlights and solutions to some of the technical challenges that both research and development (R&D) and industrial groups have encountered when ferroelectric thin film capacitors have been integrated with semiconductor devices. It presents a practical approach to integration and process-related issues that pertain to ferroelectric thin film memories—that is, ferroelectric random access memories (FeRAMs) and dynamic random access memories (DRAMs). However, some of these issues can be more generally applied to other ferroelectric thin film applications, because ferroelectric thin films have also been integrated on semiconductor circuits for these applications. The small-scale production of FeRAMs has been possible since 1991, when Ramtron Corporation made commercially available a nonvolatile 4096-bit FeRAM. In the same year, National Semiconductor Corporation demonstrated that ferroelectric thin films could be integrated on complementary metal oxide semiconductor to make a 1-transistor-l-capacitor DRAM memory cell.