High Electron Mobility in Vacuum and Ambient for PDIF-CN₂ Single-Crystal Transistors

Abstract

Single-crystal field-effect transistors (FETs) based on a fluorocarbon-substituted dicyanoperylene-3,4:9,10-bis(dicarboximide) [PDIF-CN(2)] were fabricated by lamination of the semiconductor crystal on Si-SiO(2)/PMMA-Au gate-dielectric-contact substrates. These devices were characterized both in vacuum and in the air, and they exhibit electron mobilities of ca. 6-3 and ca. 3-1 cm(2) V(-1) s(-1), respectively, I(on):I(off) > 10(3), and near-zero threshold voltage.

High-performance n-type organic field-effect transistors with ionic liquid gates

“…16,17 As organic material we have selected PDIF-CN 2 , 19,20 which exhibits the highest electron mobility reported to date ͑1-6 cm 2 / V s͒. 21 We show that the electron mobility of PDIF-CN 2 single-crystal transistors with IL ͑as high as 5.0 cm 2 / V s in air͒ is comparable to the corresponding devices without IL, thus having air as gate dielectric. Our results demonstrate that even for electronconducting materials, the use of ILs does not decrease the properties of the organic semiconductor, and that they are beneficial to improve several aspects of the device characteristics.…”

“…These values are comparable to the best electron mobilities reported for PDIF-CN 2 singlecrystal transistors. 21 Figure 2͑a͒ shows the transfer characteristics of PDIF-CN 2 single crystal OFETs after the IL ͓P13͔͓TFSI͔ has been inserted between the gate and the crystal. The simultaneously measured gate leakage current I G through the electrolytes is negligibly small as compared to the drain current I D that is less than 0.15 nA as long as ͉V G ͉ is less than 0.5 V ͓see Fig.…”

Semiconducting Organic Molecular Materials

“…OFETs based on Fig. 5 (13) single crystals with poly(methyl metacrylate) (PMMA) as the gate dielectric exhibit electron mobilities of 6 and 3 cm 2 V −1 s −1 in vacuum and in air, respectively, which are the highest reported for PDIs [23]. Fig.…”

Very low bias stress in n-type organic single-crystal transistors

“…It is particularly remarkable that such a large value of τ is observed for an n-type OFET, since these devices traditionally have suffered from substantial trapping effects due to the presence of hydroxyl groups, oxygen and water 21 . 7 We now discuss whether the experimental results give some indication as to the microscopic mechanism responsible for the bias stress in our devices. Although the time-dependent decrease in source-drain current was analyzed in terms of a stretched exponential -which is used to describe the effect of ion migration into the gate dielectric 9,10 -an equally good fit to our data with comparable values of τ and β is obtained using a stretched hyperbola…”

“…PDIF-CN 2 crystals were grown by physical vapor transport in a stream of Ar gas as reported previously 7 . After the growth, PDIF-CN 2 crystals (typically 1 µm thick and several hundreds of microns in length and width) were laminated manually onto a heavily doped Si substrate (acting as The bias stress effect was investigated both in vacuum (~10 -4 mbar) and in air, under fixed voltage polarization while measuring I DS (t) on different time scales, ranging from few hours to several days.…”