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(60)) are demonstrated. Room temperature electron and hole mobilities are in the 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 substantially the fabrication of complementary logic circuits. First circuits, such as inverters and ring-oscillators are prepared. Oscillation frequencies as high as 700 kHz are observed. (C) 2001 Elsevier Science B.V. All rights reserved.