Temperature‐Independent Transport in High‐Mobility Dinaphtho‐Thieno‐Thiophene (DNTT) Single Crystal Transistors

Abstract

The angular and temperature dependence of the field-effect mobility are investigated for p-type DNTT single crystals in a vacuum-gap structure. Temperature-independent transport behavior and weak mobility anisotropy are observed, with the best mobility approaching 10 cm(2) V(-1) s(-1) . Structural characterization and simulation suggest exceptionally high-quality and high-purity crystals.

Crossover from band-like to thermally activated charge transport in organic transistors due to strain-induced traps

“…1D shows, in black squares, the evolution of mobility with temperature for a vacuum-gap OFET. The monotonic increase in mobility with lowering temperature is a signature of band-like transport at the diF-TEG ADT-vacuum interface, similar to results obtained in other molecular crystals (20,37,38). In contrast, OFETs fabricated with the same material, but on SiO 2 dielectric, exhibit an activated behavior with a small activation energy E A = 19.7 ± 6.6 meV (Fig.…”

Single Crystal‐Like Performance in Solution‐Coated Thin‐Film Organic Field‐Effect Transistors

“…The latter shows a remarkably low trap DOS, which resembles that reported by Schmidt et al [19] for DB-TTF single crystals. Furthermore, although the method by Lang et al leads to an underestimation of the slope of the trap DOS close to the valence-band edge, DB-TTF/PS thin films show a relatively lower trap DOS than pentacene thin films [40] and are well within the range of benchmark single crystals of other organic semiconductors. [41] This is remarkable because the trap densities in single crystal OFETs can be much lower than the trap densities in the best thin films transistors.…”

“…Experiments in high-mobility single crystal OFETs, have exhibited features of band-like transport (i.e., carrier mobility increasing with lowering temperature) attributed mainly to the low concentration of traps at the organic semiconductor interface due to the employment of air-gap or low permittivity organic dielectrics and the high molecular order and absence of grain boundaries within the single crystals. [40,[44][45][46][47] Temperature independent mobility was reported for vacuum evaporated pentacene films on octadecyltrichlorosilane-treated SiO 2 dielectric, [48] while an apparent band-like transport has been observed for solution-processable pentacene derivatives and was attributed to localized transport limited by thermal lattice fluctuations rather than extendedstate conduction. [49] However, the temperature independent-mobility profile observed in the present solution processed thin films completely prepared under environmental conditions has never been observed before.…”

Flexible Electronics: Integration Processes for Organic and Inorganic Semiconductor-Based Thin-Film Transistors

“…Various research groups focus on materials such as dinaphtho(2,3-b:2′,3′-f)thieno (3,2-b)thiophene (Cn-DNTT) and 2,7-dioctyl(1)benzothieno(3,2-b)(1)benzothiophene (C8-BTBT), which can be deposit by thermal evaporation or from solutions, respectively [13][14][15][16]. Currently, the highest achieved field-effect mobility is about 43 cm 2 /Vs for C8-BTBT deposited by a special off-centered spin-coating technique [17].…”