Controllable and Versatile Electrophoretic Deposition Technology for Monolithic Organic Memory Devices

Scaling up organic nanofilm deposition from the laboratory scale to the industrial scale is an important challenge for the booming organic electronics. Herein, we propose a high-efficiency technology for organic nanofilm deposition called electrophoretic deposition (EPD). EPD was used to produce scalable films based on an ingenious molecular design by introducing the pyridinium group and flexible substituents to versatile solution-processable organic salts. EPD films with an area of 104 mm2 and controllable film thickness ranging from 50 nm to 1.55 μm can be easily fabricated using an organic solvent under different deposition conditions. Compared with traditional spin-coated films, the superior electrochemical and mechanical properties of EPD films are ascribed to their compact molecular packing, high purity, and uniform morphology. Evaluation of 2745 device units integrated into a 104 mm2 monolithic organic memory device showed that 95% of the device units possessed excellent binary data-storage performance with high stability and reproducibility, small reading bias (1.0 V), and large ON/OFF ratio (>103). Furthermore, decoating tests of EPD-based films and devices by the process of reverse EPD with switched electrode polarity suggested the potential application for information storage security and active environmental protection by simultaneously separating and recycling metal electrodes and organic materials.