Molecule-in-memory: multiscale guidelines for polymeric tunnelling layers linking molecular motifs to electrical...

Growing interest in organic nonvolatile memories based on electric field-driven charge storage highlights the need for optimized polymeric tunnelling layers (TLs). Yet, no academic standards exist, hindering technological progress. An underlying question concerns how molecular properties translate into macroscopic device characteristics. Here, we argue that the electrical characteristics of organic charge-trap memories (CTMs) are determined by the cross-relational organization of the physicochemical properties of polymeric TLs, and therefore, design needs to target relations rather than isolated properties. In the analysis, the low-k polymer of intrinsic microporosity, poly(DFBP-TTSBI-DFBP-BHPF)-co-poly(DFBP-BHPF) (P(DTDB-DB)), based on complementary nanofactors, exhibited a balanced set of properties in terms of Fowler-Nordheim tunnelling, dielectric constant, field-effect mobility, trap density, and leakage. The memory window, on/off ratio, and data retention characteristics of the CTM with a P(DTDB-DB) TL were superior to those of CTMs using conventional polymer dielectrics as TLs, and multibit operation was further demonstrated in a low-voltage device incorporating the P(DTDB-DB) TL. Lastly, detailed insights are presented, underscoring the essential role of polymeric TLs in organic CTMs and the potential of balance-oriented multi-nanofactor engineering.