Field-Effect Transistors Based on Self-Organized Molecular Nanostripes

Abstract

Charge transport properties in organic semiconductors depend strongly on molecular order. Here we demonstrate field-effect transistors where drain current flows through a precisely defined array of nanostripes made of crystalline and highly ordered molecules. The molecular stripes are fabricated across the channel of the transistor by a stamp-assisted deposition of the molecular semiconductors from a solution. As the solvent evaporates, the capillary forces drive the solution to form menisci under the stamp protrusions. The solute precipitates only in the regions where the solution is confined by the menisci once the critical concentration is reached and self-organizes into molecularly ordered stripes 100-200 nm wide and a few monolayers high. The charge mobility measured along the stripes is 2 orders of magnitude larger than the values measured for spin-coated thin films.

Direct Patterning of Organic‐Thin‐Film‐Transistor Arrays via a “Dry‐Taping” Approach

“…Patterning organic semiconductors is beneficial because it reduces or eliminates parasitic current paths (crosstalk) between neighboring devices, and results in a significant decrease in the ''off'' current. [9][10][11][12][13][14][15][16] Thin films of polymeric materials are usually prepared from solution, and can be patterned using various techniques such as screen printing, inkjet printing, molding, etc. [17][18][19][20][21][22] Small-molecule semiconducting materials have good thermal and chemical stability and typically exhibit better performance than polymers.…”

Probing the Local Conformation within π‐Conjugated One‐dimensional Supramolecular Stacks using Frequency Modulation Atomic Force Microscopy

“…S1 in the Supporting Information). The formation of thin deposits has been studied for series of similar oligomers, [29,30] which revealed that the self-assembly at surfaces is mainly governed by the molecule-molecule (or inter-segment) interactions and the molecule-substrate interactions, and leads to well-defined nanostructures, either 2D ultrathin regular layers or 1D fibrillar objects.…”

Variation in the supramolecular assembly of the molecular containerp-sulfonatocalix[4]arene, a well-known supramolecular building block

“…It has especially attracted attention when it crystallizes in large, spherical arrangements of twelve calixarene anions residing on the vertices of an icosahedron or cuboctahedron, respectively, the former mimicking the geometry of the many viruses [1,2]. Here we report a variety of novel arrangements of the p-sulfonatocalix [4]arene anion some of which include large, multi-component assemblies not conforming to the geometries of the previously reported Platonic and Archimedean solids.…”

“…Examples are inkjet or coating methods using molecules in solution. It is well established that texture can be induced by crystallisation from solvent in confined geometries with substantial impact on the charge transport properties of organic semiconductors [1]. We present two cases that may be regarded as laboratory equivalents of the "slot die" and the "immersion/dip coating" techniques of the coating industry, and demonstrate the self-organization effect of these techniques.…”