Schottky diodes and field-effect transistors based on conjugated thiophenes

Prospects of manufacturing organic semiconductor-based integrated circuits

“…Gundlach et al [59] observed that when pentacene-based OTFTs, was exposed to solvents used in photolithographic processing, the performance of the devices degraded. In a related work, Hu et al [32] reported that the mobility of the films prepared by Langmuir-Blodgett (LB) technique was cm /V s, while the mobility of same polymer films prepared by vacuum deposition techniques was cm /V s. Torsi et al [60] observed that when the -sexithiophene was subjected to rapid thermal annealing process, the grain size increased by an order of magnitude. The ratio of OTFT before annealing was 10 , and it increased to 10 when the polymer films were annealed.…”

Contactless Determination of the Photoconductivity Action Spectrum, Exciton Diffusion Length, and Charge Separation Efficiency in Polythiophene-Sensitized TiO2 Bilayers

“…Bulk heterojunctions of thiophenes and fullerenes have been found to be promising candidates for application in solar energy devices. 7,[18][19][20][21][22][23][24] In addition, junctions based on organized layers of thiophenes forming a heterojunction with organic [25][26][27] and inorganic [28][29][30][31][32] films have been investigated. Polythiophenes have certain advantages over PPVs, since thin films of substituted PTs are claimed to have self-organizing properties depending on the backbone substituents and the regioregularity.…”

“…At present, the use of thiophenes in different kinds of photoactive layers is being intensively studied. Bulk heterojunctions of thiophenes and fullerenes have been found to be promising candidates for application in solar energy devices. ,− In addition, junctions based on organized layers of thiophenes forming a heterojunction with organic − and inorganic − films have been investigated. Polythiophenes have certain advantages over PPVs, since thin films of substituted PTs are claimed to have self-organizing properties depending on the backbone substituents and the regioregularity. − Furthermore, the optical properties of PTs can be readily tailored via substitution on the main chain to obtain low-band-gap materials. , Another important property of PTs that makes them particularly suitable for solar cell applications is their enhanced photostability compared with that of PPVs.…”

Molecular Origin of Isomerization Effects on Solid State Structures and Optoelectronic Properties: A Comparative Case Study of Isomerically Pure Dicyanomethylene Substituted Fused Dithiophenes

“…Fused thiophenes, one of the most popular organic semiconductor materials, have attracted enormous interest because of their extended planar backbone framework, which can improve π–π intermolecular interactions due to the large π-conjugation found in these compounds. − In the past few decades, polythiophene − and fused polythiophene − based p-type semiconductor materials have been extensively investigated for applications in organic solar cells (OSCs) and organic field-effect transistors (OFETs). However, the development of fused thiophene-based n-type organic semiconductor materials has still largely lagged behind p-type semiconductors, − particularly for practical n-type organic semiconductor materials with high mobility and air stability. , The electron-rich nature of the thiophene ring precludes its derivatives from being air-stable n-type semiconductor materials unless one can effectively introduce strong electron-withdrawing groups onto the conjugated thiophene or fused thiophene cores. ,− Ferraris and Lambert first reported that poly-4-dicyanomethylene-4 H -cyclopenta[2,1- b :3,4- b ′]dithiophene (compound 2 ) has one of the lowest band gaps (ca.…”