Piezopotential-Programmed Multilevel Nonvolatile Memory As Triggered by Mechanical Stimuli.

We report the development of a piezopotential-programmed nonvolatile memory array using a combination of ion gel-gated field-effect transistors (FETs) and piezoelectric nanogenerators (NGs). Piezopotentials produced from the NGs under external strains were able to replace the gate voltage inputs associated with the programming/erasing operation of the memory, which reduced the power consumption compared with conventional memory devices. Multilevel data storage in the memory device could be achieved by varying the external bending strain applied to the piezoelectric NGs. The resulting devices exhibited good memory performance, including a large programming/erasing current ratio that exceeded 10, multilevel data storage of 2 bits (over 4 levels), performance stability over 100 cycles, and stable data retention over 3000 s. The piezopotential-programmed multilevel nonvolatile memory device described here is important for applications in data-storable electronic skin and advanced human-robot interface operations.