Improving Performance of Nonvolatile Perovskite‐Based Photomemory by Size Restrain of Perovskites Nanocrystals in the Hybrid Floating Gate
Weichen Yang, Yun‐Chi Chiang, Jeun‐Yan Lam, Tsung‐Han Chuang, Ender Ercan, Chu‐Chen Chueh, Wen‐Chang Chen
Abstract
Abstract Perovskite‐based photomemory adopting a floating‐gate architecture recently attracts research attention for developing efficient photo‐recording devices due to its simplified structure and non‐contact light‐programming feature. Herein, the memory characteristics of such type device is improved by the precise control of the size of perovskite nanocrystals (NCs) in the hybrid floating gate. Compared to the previous case of using polystyrene (PS) as the host polymer matrix, a N‐containing polymer, poly(2‐vinyl pyridine) (P2VP), is revealed to better regulate the size of embedded perovskite NCs into the nanometer level (7–9 nm) owing to the intense coordination between the N atom in P2VP and the Pb 2+ ions of perovskite through Lewis acid‐base interaction. As benefitting from the reduced current dissipation and interfacial charge recombination at the gate/channel interface, the P2VP‐derived photomemory not only delivers a much higher On/Off current ratio (10 5 ) than the value (10 3 ) of the reference PS‐based device but also requires a much shorter illumination time (5 s) and low drain voltage (‐1 V) to achieve decent photo‐recording function. Besides, it possesses good long‐term retention for 10 4 s, excellent stress endurance over 100 cycles, and respectable ambient stability over 6 months due to the well isolation of perovskite NCs in the P2VP matrix.