Analysing the TIPSP‐based VOFET through transistor efficiency ( g _m /I _D )

Abstract

A simple vertical organic field-effect transistor (VOFET) structure has been fabricated using ambipolar 6, 13-bis (triisopropylsilyl ethynyl) pentacene (TIPSP) with a channel length (L) of 90 nm. This device can operate at-2 V which is much lower than the voltage, reported so far for the organic devices based on TIPSP. The first time, the authors are using transistor efficiency to extract VOFET's parameters. The threshold voltage (V th) of the device has been found to vary between 0.18 and 0.38 V with the current on/off ratio (I on /I off) of 10 4. The mobility (µ) of the device has been calculated as 0.62 cm 2 /Vs. The subthreshold slope, transconductance (g m), output conductance (g d), and early voltage (V E) have been found to be 140 ± 30 mV/ decade, 2 µS, 10 −6 S, and 1.3 ± 2 V, respectively.

Modulation of Interchain Packing Orientation by Varying a Branch Point of Alkyl Substituent: Molecular Dynamics Simulation and Electrical Properties

“…A LiF layer was then deposited as the gate dielectric on top of the permeable source, followed by the Al gate electrode. Pinholes within the source electrode allowed for the accumulation of electrons at the interface between the gate dielectric and the organic semiconductor under a positive gate bias, inducing the injection of positive charge carriers from the source electrode into the PPDT2FBT-2C or PPDT2FBT-5C and the vertical charge transport toward the bottom drain electrode ( L : 150 nm, W : 0.122 cm). , The vertically structured OFET employing PPDT2FBT-2C exhibited clear gate modulation and vertical charge transport under a drain voltage ( V DS ) of −2 V, displaying an apparent mobility (μ app ) of 1.3× 10 –7 cm 2 V –1 s –1 , a V th of 0.69 V, an on/off ratio of 10 2 , and an SS of 1.8 V dec –1 (Figure e). In contrast, the drain current ( I DS ) of PPDT2FBT-5C showed little modulation with varying gate voltage ( V GS ), indicating a lack of vertical channel formation.…”