Development of Organic Memory Devices Using Radical Polymers

具有氧化还原活性的有机脂肪族聚合物作为下一代存储器件的关键材料已被应用于有机聚合物的存储中。通过合成具有设计的SOMO能级的所谓自由基聚合物，以及阐明聚合物/金属界面的电荷注入机制，可以制造出通断比大于10^5、高循环耐久性和优异的双稳态的非易失性存储器。确定了决定电双稳响应电压的因素，为全有机存储器的设计原理提供了洞察。由自由基聚合物层夹着两个金属电极制成的薄膜器件在低电压下表现出了良好的存储性能，这是基于自由基聚合物的特征电荷注入和输运行为。

Organic aliphatic polymers bearing a redox-active robust radical pendant per repeating unit have been applied as key materials for organic polymer memo-ries that are viewed as next-generation memory devices. Synthesis of the so-called radical polymers with designed SOMO levels and elucidation of charge injection mechanisms at polymer/metal interfaces allowed fabrication of nonvolatile memories with ON/OFF ratio of more than 10^5, high cycle durability, and excellent bistability. Factors that dominate the electric bistability in response to the applied voltage have been determined, which offered insight into the design principles of entirely organic organic memories. Thin devices made of the radical polymer layers sandwiched by two metal electrodes demonstrated the mem-ory properties at low applied voltages, which were based on the characteristic charge in-jection and transport behaviors found for the radical polymers.