Study of carrier behavior in pentacene in a Au/pentacene/ferroelectric poly(vinylidene fluoride-trifluoroethylene)/indium tin oxide structure by electric-field-induced second-harmonic generation measurement

Through electric-field-induced second-harmonic generation (EFISHG) measurement, we studied carrier injection and accumulation in a pentacene layer under the effect of dipole reversal in a ferroelectric poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] layer. The change in the electric field in the pentacene layer due to polarization reversal in the P(VDF-TrFE) layer was determined by direct probing. Using the value of remnant polarization of P(VDF-TrFE) obtained from displacement current measurement (DCM), we showed that the EFISHG response closely reflected the hole injection and accumulation at the pentacene/P(VDF-TrFE) interface induced by spontaneous polarization in P(VDF-TrFE).