The n-channel behavior has been occasionally reported in the organic field-effect transistors （OFETs） that usually exhibit p-channel transport only. Reconfirmation and further examination of these unusual device per...The n-channel behavior has been occasionally reported in the organic field-effect transistors （OFETs） that usually exhibit p-channel transport only. Reconfirmation and further examination of these unusual device performances should deepen the understanding on the electron transport in organic semiconductors. 6,13-bis（triisopropyl-silylethynyl） pentacene （TIPS-pentacene）, a widely examined p-channel material as Au is used for source-drain electrodes, has recently been reported to exhibit electron transport when grown from non-polar solvent on divinyltetramethyldisiloxanebis （benzocy- clobutene） （BCB） dielectric, spurring the study on this unusual electron transport. This paper describes FET characteristics of solution-grown TlPS-pentacene single crystals on five polymer gate dielectrics including polystyrene （PS）, poly（methyl methacrylate） （PMMA）, poly（4-vinyl phenol） （PVP）, poly（vinyl alcohol） （PVA） and poly（vinylidene fluoride-trifluoroethylene-chlorofluoroethylene） （P（VDF-TrFE-CFE））. In addition to the p-channel behavior, electron transport occurs in the crystals on PMMA, PS, thick PVA （40 nm） and a bilayer dielectric of PMMA on P（VDF-TrFE-CFE）, while does not on PVP and thin PVA （2 nm）. The two distinct FET characteristics are consistent with the previous reported trap effect of hydroxyl groups （in PVP and PVA） and reduced injection barrier by Na~ ions （as impurity in PVA）. The highest electron mobility of 0.48 cm2 V-1 s-1 has been achieved in the crystals on PMMA. Furthermore, the electron transport is greatly attenuated after the crystals are exposed to the vapor of a variety of polar solvents and the attenuated electron transport partially recovers if the crystals are heated, indicating the adverse effect of polar impurities on electron transport. By reconfirming the n-channel behavior in the OFETs based on TIPS-pentacene, this work has implications for the design of n-channel and ambipolar OFETs.展开更多
In this contribution, we report on the effect of solvents with different boiling points and annealing temperature on the performance of TIPS-pentacene transistors. Several solvents have been used for TIPS-pentacene th...In this contribution, we report on the effect of solvents with different boiling points and annealing temperature on the performance of TIPS-pentacene transistors. Several solvents have been used for TIPS-pentacene thin film processing: toluene, chlorobenzene and tetrahy-drofuran. To study the influence of solvent and temperature;the electrical parameters of TIPS-pentacene field effect transistor were measured. The highest values of mobilities were 7.1 × 10-3 cm2·V-1·s-1, 4.5 × 10-3?cm2·V-1·s-1 and 1.43 × 10-3 cm2·V-1·s-1 respectively for TIPS-pentacene field effect transistor using chlorobenzene, toluene and tetrahydrofuran and annealed respectively at 120°C, 150°C and 120°C. We have correlated these electrical performances with AFM images in order to point out the role of morphological properties. It is found that the grain size, and roughness highly affect the electrical parameters.展开更多
As organic thin film transistors(OTFTs)are set to play a crucial role in flexible and cost-effective electronic applica-tions,this paper investigates a high-mobility 6,13-bis(triisopropylsilylethynyl)pentacene(TIPS-pe...As organic thin film transistors(OTFTs)are set to play a crucial role in flexible and cost-effective electronic applica-tions,this paper investigates a high-mobility 6,13-bis(triisopropylsilylethynyl)pentacene(TIPS-pentacene)OTFT for use in flexi-ble electronics.The development of such high-mobility devices necessitates precise device modeling to support technology opti-misation and circuit design.The details of numerical simulation technique is discussed,in which,the electrical behavior of the device is well captured by fine tuning basic semiconductor equations.This technology computer-aided design(TCAD)has been validated with exprimental data.In addition,we have discussed about compact model fitting of the devices as well as parameter extraction procedure employed.This includes verification of Silvaco ATLAS finite element method(FEM)based results against experimental data gained from fabricated OTFT devices.Simulations for p-type TFT-based inverter are also per-formed to assess the performance of compact model in simple circuit simulation.展开更多
基金supported by the 973 Program (No.2014CB643503)National Natural Science Foundation of China (Nos.51373150,51461165301)Zhejiang Province Natural Science Foundation (No.LZ13E030002)
文摘The n-channel behavior has been occasionally reported in the organic field-effect transistors （OFETs） that usually exhibit p-channel transport only. Reconfirmation and further examination of these unusual device performances should deepen the understanding on the electron transport in organic semiconductors. 6,13-bis（triisopropyl-silylethynyl） pentacene （TIPS-pentacene）, a widely examined p-channel material as Au is used for source-drain electrodes, has recently been reported to exhibit electron transport when grown from non-polar solvent on divinyltetramethyldisiloxanebis （benzocy- clobutene） （BCB） dielectric, spurring the study on this unusual electron transport. This paper describes FET characteristics of solution-grown TlPS-pentacene single crystals on five polymer gate dielectrics including polystyrene （PS）, poly（methyl methacrylate） （PMMA）, poly（4-vinyl phenol） （PVP）, poly（vinyl alcohol） （PVA） and poly（vinylidene fluoride-trifluoroethylene-chlorofluoroethylene） （P（VDF-TrFE-CFE））. In addition to the p-channel behavior, electron transport occurs in the crystals on PMMA, PS, thick PVA （40 nm） and a bilayer dielectric of PMMA on P（VDF-TrFE-CFE）, while does not on PVP and thin PVA （2 nm）. The two distinct FET characteristics are consistent with the previous reported trap effect of hydroxyl groups （in PVP and PVA） and reduced injection barrier by Na~ ions （as impurity in PVA）. The highest electron mobility of 0.48 cm2 V-1 s-1 has been achieved in the crystals on PMMA. Furthermore, the electron transport is greatly attenuated after the crystals are exposed to the vapor of a variety of polar solvents and the attenuated electron transport partially recovers if the crystals are heated, indicating the adverse effect of polar impurities on electron transport. By reconfirming the n-channel behavior in the OFETs based on TIPS-pentacene, this work has implications for the design of n-channel and ambipolar OFETs.
文摘In this contribution, we report on the effect of solvents with different boiling points and annealing temperature on the performance of TIPS-pentacene transistors. Several solvents have been used for TIPS-pentacene thin film processing: toluene, chlorobenzene and tetrahy-drofuran. To study the influence of solvent and temperature;the electrical parameters of TIPS-pentacene field effect transistor were measured. The highest values of mobilities were 7.1 × 10-3 cm2·V-1·s-1, 4.5 × 10-3?cm2·V-1·s-1 and 1.43 × 10-3 cm2·V-1·s-1 respectively for TIPS-pentacene field effect transistor using chlorobenzene, toluene and tetrahydrofuran and annealed respectively at 120°C, 150°C and 120°C. We have correlated these electrical performances with AFM images in order to point out the role of morphological properties. It is found that the grain size, and roughness highly affect the electrical parameters.
基金The DST government of India is appreciated by the researchers for giving them the early career research grant under the project ECR/2017/000179。
文摘As organic thin film transistors(OTFTs)are set to play a crucial role in flexible and cost-effective electronic applica-tions,this paper investigates a high-mobility 6,13-bis(triisopropylsilylethynyl)pentacene(TIPS-pentacene)OTFT for use in flexi-ble electronics.The development of such high-mobility devices necessitates precise device modeling to support technology opti-misation and circuit design.The details of numerical simulation technique is discussed,in which,the electrical behavior of the device is well captured by fine tuning basic semiconductor equations.This technology computer-aided design(TCAD)has been validated with exprimental data.In addition,we have discussed about compact model fitting of the devices as well as parameter extraction procedure employed.This includes verification of Silvaco ATLAS finite element method(FEM)based results against experimental data gained from fabricated OTFT devices.Simulations for p-type TFT-based inverter are also per-formed to assess the performance of compact model in simple circuit simulation.
