Oligomer Hydrate Crystallization Improves Carbon Nanotube Memory

Abstract

Single-walled carbon nanotube (SWCNT) field-effect transistor (FET) devices have potential for memory storage applications. Devices fabricated with semiconducting SWCNT ink using dielectrophoresis were coated with a renewably sourced poly(oxacyclobutane) oligomer. It was found that this oligomer crystallizes with water to form a semicrystalline oligomer hydrate material. Crystallization also occurs on the SWCNT device surface in ambient conditions, resulting in dramatically increased hysteresis of the SWCNT-FET I-Vg curves. Using alternating current impedance measurements, we found that the oligomer hydrate crystals store charge, acting as a capacitor encapsulating the nanotube network. This capacitive material can serve to electrostatically gate the SWCNT network. The charge storage properties of the oligomer hydrate crystals were applied to store “0” and “1” bits separated by ∼4 orders of magnitude of current. Utilizing powder X-ray diffraction and simulation, we have demonstrated that this semicrystall...