A Flexible Carbon Nanotube Sen-Memory Device

Abstract

In a modern electronics system, charge-coupled devices and data storage devices are the two most indispensable components. Although there has been rapid and independent progress in their development during the last three decades, a cofunctionality of both sensing and memory at single-unit level is yet premature for flexible electronics. For wearable electronics that work in ultralow power conditions and involve strains, conventional sensing-and-memory systems suffer from low sensitivity and are not able to directly transform sensed information into sufficient memory. Here, a new transformative device is demonstrated, which is called “sen-memory”, that exhibits the dual functionality of sensing and memory in a monolithic integrated circuit. The active channel of the device is formed by a carbon nanotube thin film and the floating gate is formed by a controllably oxidized aluminum nanoparticle array for electrical- and optical-programming. The device exhibits a high on–off current ratio of ≈106, a long-term retention of ≈108 s, and durable flexibility at a bending strain of 0.4%. It is shown that the device senses a photogenerated pattern in seconds at zero bias and memorizes an image for a couple of years.