Type control of Single Walled Carbon Nanotube field effect transistors and Its application

Permanently type controlled single walled carbon nanotube (SWNT) field effect transistors, from p-type, ambi-polar to n-type, have been fabricated by controlling deposition temperature of Al$_{2}$O$_{3}$ film as top-gate dielectric by atomic layer deposition (ALD). It is observed that threshold voltage (Vth) is almost linearly downshifted as a function of deposition temperature. Competition between electron transfer from the of Al$_{2}$O$_{3}$ layers to the SWNT surface and electron capture by oxygen molecules adsorbed on the tube wall seems to be the key point for the Vth change depending on the deposition temperature. To prove the high performance of type controlled SWNT network transistors, inverter, NAND, and NOR gate characteristics are successfully demonstrated.