PUB-2014-COC

Characterization of current transport mechanism in ferroelectric polymer devices

Amir Hanna, Unnat Bhansali, M.A. Khan, and H.N. Alshareef, “Characterization of current transport mechanism in ferroelectric polymer devices”
Organic Electronics
Volume 15, Issue 1, January 2014, Pages 22–28
Amir Hanna, Unnat Bhansali, M.A. Khan, and H.N. Alshareef
P(VDF-TrFE) capacitors; Charge injection; Charge-transport mechanisms; I–V analysis
2014
We report the charge injection characteristics in poly(vinylidene fluoride-trifluoroethylene), P(VDF-TrFE), as a function of electrode material in metal/ferroelectric/metal device structures. Symmetric and asymmetric devices with Al, Ag, Au and Pt electrodes were fabricated to determine the dominant carrier type, injection current density, and to propose transport mechanisms in the ferroelectric polymer. Higher work function metals such as Pt are found to inject less charges compared to lower work function metals, implying n-type conduction behavior for P(VDF-TrFE) with electrons as the dominant injected carrier. Two distinct charge transport regimes were identified in the P(VDF-TrFE) devices; a Schottky-limited conduction regime for low to intermediate fields (E < 20 MV/m), and a space-charge limited conduction (SCLC) regime for high fields (20 < E < 120 MV/m). Implication of these results for degradation in P(VDF-TrFE) memory performance are discussed.