Triggering WORM/SRAM Memory Conversion in a Porphyrinated Polyimide via Zn Complexation as the Internal Electrode

Abstract

We design two novel solution processable polyimides (PIs), NH-Por-6FDA and Zn-Por-6FDA, with 5,15-bis(4,-aminophenyl)-10,20-diphenylporphyrin (trans-DATPP) (electron donor) and 4,4′-(hexafluoroisoprpoylidine)diphthalic anhydride (6FDA) (electron acceptor) as the building blocks for polymer memory applications. The chemical structures of the two polymers are mostly identical with the only difference lying in the zinc ion (Zn2+) insertion into the porphyrin core in the Zn-Por-6FDA. Electrical characterization indicates that the NH-Por-6FDA possesses bidirectional nonvolatile write once read many times (WORM) memory behavior, while the Zn-Por-6FDA shows vastly different volatile static random access memory (SRAM) behavior. Both polymer memory devices show high ON/OFF current ratio up to 106 and exhibit excellent long-term operation stability in 108 read cycles and retention time of 4000 s with no current degradation. The charge transfer (CT) and function of the donor/acceptor moiety in the polymers related w...