European memory research

To explore solutions to overcome the scaling limitations of conventional flash memory, IMEC, a European research organisation, has started research activities on resistive RAM (RRAM) cells.

Resistive switching memories are based on materials whose resistivity can be electrically switched between high and low conductive states. RRAM is becoming of interest for future scaled memories because of their superior intrinsic scaling characteristics compared to the charge-based flash devices and potentially small cell size (enabling dense crossbar RRAM arrays using vertical diode selecting elements).

RRAM is seen as a potential candidate to replace conventional flash memory and there is a push of NVM technology towards the sub 22 nm technology node.

For making RRAM, different concepts and materials are proposed. IMEC's research mainly focuses on investigating the switching behaviour of the RRAM cell concept that uses metal oxides as a switching element and on demonstrating its scaling capability down to 25 nm. The study concentrates on three main topics, being RRAM stack optimisation (including the choice of top and bottom electrode and of the metal oxide), RRAM cell scaling and RRAM integration in a crossbar RRAM array.

The research is part of IMEC's emerging memory prgram that provides non-volatile memory concepts and solutions for the 32 nm generation and below.