A High-Performance Optical Memory Array Based on Inhomogeneity of Organic Semiconductors

Abstract

Organic optical memory devices keep attracting intensive interests for diverse optoelectronic applications including optical sensors and memories. Here, flexible nonvolatile optical memory devices are developed based on the bis[1]benzothieno[2,3-d;2′,3′-d′]naphtho[2,3-b;6,7-b′]dithiophene (BBTNDT) organic field-effect transistors with charge trapping centers induced by the inhomogeneity (nanosprouts) of the organic thin film. The devices exhibit average mobility as high as 7.7 cm² V⁻¹ s⁻¹, photoresponsivity of 433 A W⁻¹, and long retention time for more than 6 h with a current ratio larger than 10⁶. Compared with the standard floating gate memory transistors, the BBTNDT devices can reduce the fabrication complexity, cost, and time. Based on the reasonable performance of the single device on a rigid substrate, the optical memory transistor is further scaled up to a 16 × 16 active matrix array on a flexible substrate with operating voltage less than 3 V, and it is used to map out 2D optical images. The findings reveal the potentials of utilizing [1]benzothieno[3,2-b][1]benzothiophene (BTBT) derivatives as organic semiconductors for high-performance optical memory transistors with a facile structure. A detailed study on the charge trapping mechanism in the derivatives of BTBT materials is also provided, which is closely related to the nanosprouts formed inside the organic active layer.

A high-performance organic optical memory array is developed based on the structural inhomogeneity of bis[1]benzothieno[2,3-d;2′,3′-d′]naphtho[2,3-b;6,7-b′]dithiophene organic semiconductors with charge trapping centers induced by the nanosprouts in the thin film. The flexible 16 × 16 array can encrypt and store 2D optical images. The findings reveal the potentials of utilizing [1]benzothieno[3,2-b][1]benzothiophene derivatives for high-performance optical memory transistors with a facile structure.

http://ift.tt/2EQy2AO