Programmable Ferroelectric HZO NEMS Mechanical Multiplier for in-Memory Computing

This work presents the first-ever NEMS-based in-memory computing device that uses ultra-thin ferroelectric hafnium zirconium oxide (HZO) as the weight storage unit. The HZO unimorph’s piezoelectric properties can be tuned by applying a poling voltage (V p ) from -8V to 8V across a 20-nm HZO film. The unimorph displacement, both at resonance and off-resonance, is found to be proportional to the product of V p and V in , where V in is the input drive voltage when operating in compute mode. The NEMS device demonstrates analog multiplication, without electrical contacts, and consumes attoJoules of energy. The HZO-based unimorphs are scalable to nano-scale dimensions owing to the ultrathin HZO layer. This device provides the possibility of arraying of the unimorphs with capacitive readout for massively parallel MAC (Multiply and Accumulate) units.