Ambipolar organic devices for complementary logic

Ambipolar field-effect transistors based on single crystals of a variety of organic semiconductors (pentacene, tetracene, sexithiophene, perylene, C-6 0) are demonstrated. Room temperature electron and hole mobilities are in t he order of 1-5 cm(2)/V s for these compounds. Because no organic material has to be patterned, the use of ambipolar devices might simplify substantia lly the fabrication of complementary logic circuits. First circuits, such a s inverters and ring-oscillators are prepared. Oscillation frequencies as h igh as 700 kHz are observed. (C) 2001 Elsevier Science B.V. All rights rese rved.