Bismuth based layered perovskite thin films as a charge storage material for low power nonvolatile GaAs memory applications

This work details initial process development and integration of ferroelectric SrBi2Ta2O9 and SrBi2Ta2(1-x)Nb2xO9 for use in low power nonvolatile GaAs memory technology. A spin on process is used to deposit the ferroelectric thin films. Capacitance, hysteresis loop, and switched charge versus time data are presented for metal-ferroelectric-metal capacitors using platinum as the electrode material. Indications are that the substitution of niobium for tantalum in the layered perovskite structure increases both the non-volatile polarization and the coercive field of the material. N-channel transistor characteristics of the low power gallium arsenide field effect transistor contained in the 1T-1C memory bit are also presented. The results presented here imply that these materials warrant further research and process integration studies to realize low power non-volatile GaAs memory technology.