Pentacene disproportionation during sublimation for field-effect transistors

by Roberson, L. B.; Kowalik, J.; Tolbert, L. M.; Kloc, C.; Zeis, R.; Chi, X. L.; Fleming, R.; Wilkins, C.

At moderate temperatures in flowing gas, pentacene undergoes a disproportionation reaction to produce 6,13-dihydropentacene (DHP) and a series of polycondensed aromatic hydrocarbons, including the previously unknown peripentacene (PP). The process requires activation by heating to 320 degreesC and is possibly catalyzed by impurities such as DHP, 6,13-pentacenequinone (PO), Al, or Fe found in the starting materials. These impurities also result in a decrease in the intrinsic field-effect mobility (FEM) of pentacene crystals. Subsequent purifications remove such impurities, thus inhibiting the formation of the disproportionation products and increasing the FEM of pentacene (2.2 cm(2)/Vs). These results clarify the importance of purification of semiconductive materials for measurements of intrinsic mobility and optimal device performance.

Journal
Journal of the American Chemical Society
Volume
127
Issue
9
Year
2005
Start Page
3069-3075
URL
https://dx.doi.org/10.1021/ja044586r
ISBN/ISSN
1520-5126; 0002-7863
DOI
10.1021/ja044586r