AVS 49th International Symposium
    Nanotubes: Science and Applications Topical Conference Tuesday Sessions
       Session NT-TuM

Paper NT-TuM1
Room Temperature Coulomb Diamond Characteristics in Single Electron Transistor with Position Controlled Grown Carbon Nanotube Channel

Tuesday, November 5, 2002, 8:20 am, Room C-209

Session: Nanotubes: Electronics and Field Emission
Presenter: K. Matsumoto, National Institute of Advanced Industrial Science & Technology, Japan
Authors: K. Matsumoto, National Institute of Advanced Industrial Science & Technology, Japan
T. Kamimura, Tsukuba University, Japan
M. Maeda, Meiji University, Japan
K. Sakamoto, Meiji University, Japan
K. Kurachi, Meiji university, Japan
Correspondent: Click to Email
Even at room temperature, the clear Coulomb diamond structures were obtained in the single electron transistor which used the position controlled grown carbon nanotube as a channel, and Coulomb energy of the device is as high as 400meV. The position contr ol of the carbon nanotube for the channel of the device was successfully achieved using the patterned chemical catalyst process without any difficulty, i.e., using the conventional photo-lithography process, 3 nm thick iron (Fe) catalyst was patterned fo r the source and drain structure on the SiO@sub 2@/Si substrate. Using the thermal CVD process, one carbon nanotube started to grow and bridged the gap between the source and drain patterned Fe catalysts. Ohmic metal was then deposited on to the source an d drain regions and on the backside of the Si substrate for the gate. The electrical properties of the device were all measured at room temperature. The device showed the large Coulomb gap of 800mV at around zero gate bias and the Coulomb energy of the de v ice is as high as 400meV that correspond to Coulomb temperature of 5000K. The Coulomb oscillation characteristics was also obtained and its modulation ratio is as high as 96~99% at the drain bias of around 20mV ~100mV even at room temperature. Five Coul omb diamond structures were obtained between the gate bias of @+ -@2V with the different structures sizes. This may come from the multi-islands formation by the residual chemical catalysts and/or the defects in the carbon nanotube. The corresponding island size is only 1nm diameter sphere. Using the position controlled grown carbon nanotube as a channel, ultra-high Coulomb energy of the single electron transistor is easily realized.