Shift dynamics of capillary self-alignment

This paper describes the dynamics of capillary self-alignment of components with initial shift offsets from matching receptor sites. The analysis of the full uniaxial self-alignment dynamics of foil-based mesoscopic dies from pre-alignment to final settling evidenced three distinct, sequential regimes impacting the process performance. The dependence of accuracy, alignment time and repeatability of capillary self-alignment on control parameters such as size, weight, surface energy and initial offset of assembling dies was investigated. Finally, we studied the influence of the dynamic coupling between the degenerate oscillation modes of the system on the alignment performance by means of pre-defined biaxial offsets

High-Performance Solution-Processable Poly(p-phenylene vinylene)s for Air-Stable Organic Field-Effect Transistors

The influence of the substitution pattern (unsymmetrical or symmetrical), the nature of the side chain (linear or branched), and the processing of several solution processable alkoxy-substituted poly(p-phenylene vinylene)s (PPVs) on the charge-carrier mobility in organic field-effect transistors (OFETs) is investigated. We have found the highest mobilities in a class of symmetrically substituted PPVs with linear alkyl chains (e.g., R1, R2 = n-C11H23, R3 = n-C18H37). We have shown that the mobility of these PPVs can be improved significantly up to values of 10-2 cm2 V-1 s-1 by annealing at 110°C. In addition, these devices display an excellent stability in air and dark conditions. No change in the electrical performance is observed, even after storage for thirty days in humid air.