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The rediscovery and the memory application of single walled carbon nanotubes (SWNTs) give a new method in nanoelectronics applications. At first we will report the memory effects of a SWNT, and attempt to use this property in a memory device. To use a SWNT field effect transistor (FET) as a charge-storage memory device, the device operates by injecting electrons from the nanotube channel of a TubeFET into charge traps on the surface of the SiO 2 gate dielectric, thus shifting the threshold voltage. This memory can be written and erased many times, and has a hold time of hundreds of seconds at room temperature. At second we have attempted to make a Peapod tubeFET. It is the structure that a C 60 was contained within the tube and separated from it by a graphitic Van der Waals gap. I-V property of the Peapod shows semiconducting property.

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Because the chemical states of the elements in SrTiO, thin film on Si are reduced by argon ion beam bombardment, it was impossible to sputter depth profile the chemical states of SrTiO, thin film by argon ion beams. In this paper, it is reported that the undistorted chemical states of Ti and Si a t the SrTiO,/Si interface can be determined with oxygen ion beams a t the appropriate 70' angle of incidence, with which either metallic Ti is not oxidized or Ti in SrTiO, is not reduced. Under the sputter depth profiling conditions, the chemical state of Ti a t the SrTiO,/Si interface could be successfully characterized and the effects of post-annealing at high temperature on the chemical state of Ti were studied. A significant number of Ti atoms in the metallic state were observed at the SrTiO,/Si interface without any post-annealing but all of them were oxidized to the Ti4+ chemical state after 2 h postannealing a t the temperatures above 600 OC under oxygen flow. The dielectric properties of SrTiO, thin films on Si were well correlated to the oxidation state of Ti and the broadening of the interface SiO, layer induced by postannealing a t high temperature.