Over the last years carbon nanotubes (CNs) have attracted an increasing interest as building blocks for nano-electronics applications. Due to their unique properties enabling e.g. ballistic transport at room-temperature over several hundred nanometers, high performance CN field-effect transistors (FETs) have become feasible. The successful improvement of CNFET performance however is not merely a result of the application of established concepts. It is indeed a consequence of the detailed study of the material specific properties that have guided the research on CN-based transistor applications. An example of this is the critical observation that CNFETs in fact behave as Schottky barrier devices. It was found that switching in nanometer size semiconductors, such as carbon nanotubes, contacted with source/drain metal electrodes is determined entirely by the metal/semiconductor interfaces and their field-dependence. Making use of this particular type of nanotube property, we have been able to relate the performance of nanotube devices with their diameters and recently successfully fabricated the first band-to-band tunneling CNFET. This device shows a much more abrupt switching behavior than can be obtained with any conventional transistor approach, evidence that nano-materials can be used to create drastically different and more efficient switches in principal. Our latest accomplishment is to combine carbon nanotube transistors in a CMOS-type 5-stage ring oscillator, an important demonstration that elevates nanotube applications from the devices level to the circuit level and allows for the more detailed study of their high frequency properties.

Researchers should cite this work as follows:

• Joerg Appenzeller (2006), "Logic Devices and Circuits on Carbon Nanotubes," http://nanohub.org/resources/1487.

  BibTex | EndNote

1. ballistic MOSFET
2. carbon nanotubes
3. circuits
4. devices
5. material science
6. molecular electronics
7. nanoelectronics
8. nanotransistors
9. NEGF
10. research seminar