title: Electrical and optical properties of diketopyrrolopyrrole-based copolymer interfaces in thin film devices.
abstract: Two donor-acceptor diketopyrrolopyrrole (DPP)-based copolymers (PDPP-BBT and TDPP-BBT) have been synthesized for their application in organic devices such as metal-insulator semiconductor (MIS) diodes and field-effect transistors (FETs). The semiconductor-dielectric interface was characterized by capacitance-voltage and conductance-voltage methods. These measurements yield an interface trap density of 4.2 × 10(12) eV⁻¹ cm⁻² in TDPP-BBT and 3.5 × 10¹² eV⁻¹ cm⁻² in PDPP-BBT at the flat-band voltage. The FETs based on these spincoated DPP copolymers display p-channel behavior with hole mobilities of the order 10⁻³ cm²/(Vs). Light scattering studies from PDPP-BBT FETs show almost no change in the Raman spectrum after the devices are allowed to operate at a gate voltage, indicating that the FETs suffer minimal damage due to the metal-polymer contact or the application of an electric field. As a comparison Raman intensity profile from the channel-Au contact layer in pentacene FETs are presented, which show a distinct change before and after biasing.
authors: Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA.
authors: Danish
authors: D
authors: Adil
authors: Catherine
authors: C
authors: Kanimozhi
authors: Ndubuisi
authors: N
authors: Ukah
authors: Keshab
authors: K
authors: Paudel
authors: Satish
authors: S
authors: Patil
authors: Suchi
authors: S
authors: Guha