Figure 3 : Illustration and characterization of the asymmetric-contact SWCNT p-i-n diode.

From: Carbon nanotube intramolecular p-i-n junction diodes with symmetric and asymmetric contacts

Figure 3

(a) Schematic diagram of Pd/Al asymmetrically contacted p-i-n SWCNT device. Pd and Al were chosen as the drain and source, respectively. The window of PMMA near the Pd side was used for OA doping to obtain a p-type SWCNT and another one near the Al side was used for PEI doping to cause the SWCNT to become n-type. The middle area was always protected by PMMA and kept its intrinsic semiconductor properties. The length of each section (p, i, n) was about 650 nm. (b) SEM image of the Pd/SWNT/Al device. The left electrode is Pd and the right electrode is Al. The width of the channel is ~2 μm.