With the advancement of the information society, the demand for highly integrated and multi-functional electronic devices is rapidly increasing. To meet these demands, high-performance transistors with low power consumption, high-speed operating, and mechanical flexibility are essential. Among various candidates, semiconducting single-walled carbon nanotubes (s-SWCNT)-based transistors, which exhibit intrinsically ambipolar characteristics, have emerged as promising components for CMOS-like circuits. In this study, s-SWCNT were selectively dispersed using rr-P3DDT, a thiophene-based conjugated polymer, and filed-effect transistors (FETs) were fabricated by inducting directional alignment for enhanced charge transport through an off-centered spin-coating process. The electrical characteristics of the fabricated s-SWCNT FETs were evaluated under various thermal annealing conditions (100℃, 150℃, 200℃, and 250℃). Off-centered spin-coated and high temperature annealed s- SWCNT FETs exhibited high field-effect mobilities over 5 cm²/Vs in both p-type and n-type operation, along with ideal Vshaped ambipolar transfer curves. These results indicate a significant enhancement in ambipolar performance due to efficient desorption of residual oxygen and water molecules in active channel via high temperature annealing. Furthermore, CMOS-like inverter circuits demonstrated an ideal inversion voltage (VIN = VDD/2) and a high voltage gain of approximately 9.5. These findings highlight the potential of SWCNT-based materials for realizing next-generation flexible electronic circuits that combine high-performance, energy efficiency, and simplified solution-processing.
Herein, we report the manufacture of high-performance, ambipolar organic field-effect transistors (OFETs) and complementary-like electronic circuitry based on a blended, polymeric, semiconducting film. Relatively high and wellbalanced electron and hole mobilities were achieved by incorporating a small amount of ionic additives. The equivalent P-channel and N-channel properties of the ambipolar OFETs enabled the manufacture of complementary-like inverter circuits with a near-ideal switching point, high gain, and good noise margins, via a simple blanket spin-coating process with no additional patterning of each active P-type and N-type semiconductor layer.
In this study, we examine the electrical properties of diketopyrrolopyrrole (DPP) containing polymer semiconductors that have been reported to show high performance with ambipolar characteristics. We prepared three different DPP based polymer semiconductors (PDPPTPT, PDPP3T, and PDPP2T-TT) and fabricated organic thin film transistors (OTFTs) with ambipolar polymer semiconductors as an active layer. All three DPP polymers showed only p-type properties at initial measurements. However, after annealing in vacuum oven for 24 hours, it was found that the DPP based polymers have both p-type and n-type properties. It is speculated that the residual impurities supposedly regarded as a strong electron trap source were eliminated during the vacuum process.