The influence of chemical surface modifications of gold electrodes on the morphology and the electrical properties has been studied for pentacene based thin-film transistors with channel lengths of L⩽4μm. Self-assembled monolayers (SAMs) of various aliphatic and aromatic organothiols have been used to selectively modify the metallic source and drain electrodes and are further compared with reference samples with untreated electrodes. For all SAM-treated devices a reduced roughness of the pentacene film is observed which is accompanied by a reduction of the threshold voltage from about VT=2V for untreated transistors to −0.9V for transistors with SAM modified electrodes. Using aliphatic SAMs a poor on/off ratio of about 102 was obtained which is attributed to their low conductivity. In contrast, the on/off ratio is enhanced by four orders of magnitude if the surface is modified by an aromatic SAM. In this case a subthreshold swing as low as 0.55V/decade is achieved which corresponds to a trap density reduced by one order of magnitude compared to the reference sample.

The Internet of Things is driving extensive efforts to develop intelligent everyday objects. This requires seamless integration of relatively simple electronics, for example through ‘stick-on' electronics labels. We believe the future evolution of this technology will be governed by Wright's Law, which was first proposed in 1936 and states that the cost of a product decreases with cumulative production. This implies that a generic electronic device that can be tailored for application-specific requirements during downstream integration would be a cornerstone in the development of the Internet of Things. We present an 8-bit thin-film microprocessor with a write-once, read-many (WORM) instruction generator that can be programmed after manufacture via inkjet printing. The processor combines organic p-type and soluble oxide n-type thin-film transistors in a new flavor of the familiar complementary transistor technology with the potential to be manufactured on a very thin polyimide film, enabling low-cost flexible electronics. It operates at 6.5 V and reaches clock frequencies up to 2.1 kHz. An instruction set of 16 code lines, each line providing a 9 bit instruction, is defined by means of inkjet printing of conductive silver inks.

In pentacene-based bottom-contact field-effect transistors, the authors study the influence of anthracene-2-thiol-modified gold electrodes on the morphology, the contact and sheet resistance, the trap density, and the charge-carrier activation energy. The data are compared to reference samples with untreated gold electrodes. Anthracene-2-thiol treatment leads to a reduced sheet resistance, a reduced activation energy, and an improved film morphology.

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We study the effect of gallium and yttrium doping on both the electrical performance and the stability of indium based metal-oxide thin-film transistors (MOTFTs) at varied concentrations.

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Semiconductor inks containing an indium-based oxo alkoxide precursor material were optimized regarding rheology requirements for a commercial 10 pL inkjet printhead. The rheological stability is evaluated by measuring the dynamic viscosity of the formulations for 12 h with a constant shear rate stress under ambient conditions. It is believed that the observed superior stability of the inks is the result of effectively suppressing the hydrolysis and condensation reaction between the metal oxo alkoxide precursor complex and atmospheric water. This can be attributed to a strong precursor coordination and the resulting reduction in ligand exchange dynamics of the solvent tetrahydrofurfuryl alcohol which is used as the main solvent in the formulations. It is also shown that with a proper selection of cosolvents, having high polar Hansen solubility parameter values, the inks drop formation properties and wettability can be fine-tuned by maintaining the inks rheological stability. Good drop jetting performance without satellite formation and high drop velocities of 8.25 m/s were found with the support of dimensionless numbers and printability windows. By printing single 10 pL ink dots onto short channel indium-tin-oxide electrodes, InO calcination at 350 °C and a solution-processed back-channel protection, high average saturation mobility of approximately 10 cm/(V s) are demonstrated in a bottom-contact coplanar thin-film transistor device structure.