Air-stable n-channel single-crystal transistors with negligible threshold gate voltage

Single-crystal transistors of highly electron-affine organic compounds were constructed on solid dielectrics to study intrinsic constraints for the n-channel field effect in ambient atmosphere. Tetracyanoquinodimethane field-effect devices reproducibly operate with a high mobility of 0.2–0.5 cm2/V s in the air. The threshold gate voltage is negligible unlike most other air-stable n-type organic transistors reported, including polycrystal film devices of the same compound. Together with the other example of less electron-affine semiconductor crystal showing air-stable field effect but with notable threshold voltage, the result suggests that crucial in air-stable n-channel field effect is sufficient electron-affinity of the organic semiconductors.