A reversible and reproducible conductance transition is realized in the monolayer of polyimide (PI) Langmuir−Blodgett film on Au (111) substrate with a scanning tunneling microscopy (STM). The high-conductance state can be induced by applying a voltage pulse of about −2.7 V using the STM lithography method. The PI monolayer can spontaneously recover to its original low conductance state under a normal STM scanning condition. An electron trapping/detrapping process in the PI molecule can be responsible for its conductance transition. The reversible and highly reproducible conductance switching behavior in the PI film could provide its potential applications in the molecular logic and memory devices.
