| Abstract
| - At moderate temperatures in flowing gas, pentacene undergoes a disproportionation reaction toproduce 6,13-dihydropentacene (DHP) and a series of polycondensed aromatic hydrocarbons, includingthe previously unknown peripentacene (PP). The process requires activation by heating to 320 °C and ispossibly catalyzed by impurities such as DHP, 6,13-pentacenequinone (PQ), Al, or Fe found in the startingmaterials. These impurities also result in a decrease in the intrinsic field-effect mobility (FEM) of pentacenecrystals. Subsequent purifications remove such impurities, thus inhibiting the formation of the disproportionation products and increasing the FEM of pentacene (2.2 cm2/Vs). These results clarify the importanceof purification of semiconductive materials for measurements of intrinsic mobility and optimal deviceperformance.
|
