23 bits optical sensor based on nonvolatile organic memory transistor

Polymer electret transistor memory device has stable charge storage and memory properties. Here, we combine a large band gap organic semiconductor dinaphtho[2,3-b:2',3'-f] thieno[ 3,2-b] thiophene with the polystyrene electret to form an optical sensor with memory effect. The blue light combined with programming bias leads to a positive threshold voltage shift for more than 100 V while the drain-source current shows a variation of seven orders of magnitude. The dynamic range of current device is up to 23 bits and the photo responsivity is 420 A W-1. The optically programmed transistor can be directly used for high-resolution optical sensor and multi-level data storage applications. (C) 2014 AIP Publishing LLC.