2 research outputs found
Engineering High‑<i>k</i> Oxide/CuSCN Interface for p‑Channel Thin-Film Transistors
Copper(I) thiocyanate (CuSCN) is a unique coordination
polymer
semiconductor with excellent hole-transport properties and a wide
band gap. CuSCN enables the construction of thin-film transistors
(TFTs) based on a transparent p-type inorganic channel layera
rare component. Despite the tremendous progress of TFTs based on transparent
n-type oxides, the development of the p-type counterparts has been
limited, especially for TFTs based on CuSCN. In this work, we explored
three aspects in bottom-gate top-contact TFTs: the use of high-k metal oxides (AlOx, GaOx, and HfOx) as
the dielectric layer, organic molecules (methacrylic acid or MAA and
tetraethyl orthosilicate or TEOS) as the dielectric passivation layer,
and an antisolvent (tetrahydrofuran or THF) to improve the hole-transport
properties. The best condition was found to be AlOx annealed at 200 °C with the TEOS layer as the dielectric
combined with THF-treated CuSCN as the semiconducting channel. The
resulting TFTs operated under low voltages and showed a field-effect
hole mobility in the range of 7–8 × 10–3 cm2 V–1 s–1, representing
an increase of 4- to 5-fold from the previous report. In particular,
the TEOS passivation layer and THF treatment increased the mobility
as a result of the reduced trap state density
Influence of Side-Chain Regiochemistry on the Transistor Performance of High-Mobility, All-Donor Polymers
Three novel polythiophene isomers
are reported whereby the only
difference in structure relates to the regiochemistry of the solubilizing
side chains on the backbone. This is demonstrated to have a significant
impact on the optoelectronic properties of the polymers and their
propensity to aggregate in solution. These differences are rationalized
on the basis of differences in backbone torsion. The polymer with
the largest effective conjugation length is demonstrated to exhibit
the highest field-effect mobility, with peak values up to 4.6 cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup>