Ultralow Power Consumption Flexible Biomemristors

Low power consumption is the important requirement in memory devices for saving energy. In particular, improved energy efficiency is essential in implantable electronic devices for operation under a limited power supply. Here, we demonstrate the use of K-carrageenan (kappa-car) as the resistive switching layer to achieve memory that has low power consumption. A carboxymethyl (CM) group is introduced to the kappa-car to increase its ionic conductivity. Ag was doped in CM:kappa-car to improve the resistive switching properties of the devices. Memory devices based on Ag-doped CM:kappa-car showed electroforming-free resistive switching. This device exhibited low reset voltage (similar to 0.05 V), fast switching speed (50 ns), and high on/off ratio (>10(3)) under low compliance current (10(-5) A). Its power consumption (similar to 0.35 mu W) is much lower than those of the previously reported biomemristors. The resistive switching may be a result of an electrochemical redox process and Ag filament formation in the CM:kappa-car under an electric field. This biopolymer memory can also be fabricated on flexible substrate. This study verifies the feasibility of using biopolymers for applications to future implantable and biocompatible nanoelectronics.