Improvement of Electrical and Thermal Contacts Between Carbon Nanotubes and Metallic Electrodes by Laser Annealing

Autor(es)

Silveira, J. V. ^{[1, 2]} ; Savu, R. ^[2] ; Canesqui, M. A. ^[2] ; Alves, O. L. ^[3] ; Mendes Filho, J. ^[1] ; Swart, J. W. ^[4] ; Souza Filho, A. G. ^[1] ; Moshkalev, S. A. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Ceara, Dept Fis, BR-60455900 Fortaleza, Ceara - Brazil

^[2] Univ Estadual Campinas, Ctr Componentes Semicond, BR-13083870 Campinas, SP - Brazil

^[3] Univ Estadual Campinas, Inst Ouim, Lab Quim Estado Solido, BR-13083970 Campinas, SP - Brazil

^[4] Univ Estadual Campinas, Fac Engn Eletr & Comp, BR-13083852 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF NANOELECTRONICS AND OPTOELECTRONICS; v. 9, n. 3, p. 374-380, JUN 2014.
• Citações Web of Science: 4

Resumo

A new approach for improving electrical and thermal contacts between multi-wall carbon nanotubes (MWCNTs) and metal electrodes by localized laser heating is presented in this work. The nanotubes were suspended, using the dielectrophoresis technique, over a gap of 1 mu m width and 5 mu m depth connecting the ends of the patterned electrodes. Subsequently, the as deposited nanotubes were directly heated, in ambient atmosphere, by a focused laser beam, which was also used for exciting the Raman spectra of the nanotubes. The changes in the vibrational frequencies were used to estimate the local temperature that was controlled by the incident laser power density. The changes in the nanotubes due to laser heating were evaluated by using scanning electron microscopy, Raman spectroscopy and electrical measurements. The method was employed for improving the electrical contacts between suspended MWCNTs and different electrodes (W, Ti and Au). The reduction in the electrical resistance was up to three orders of magnitude, resulting in contact resistivity as low as similar to 0.1-1 k Omega.mu m(2), with the lowest values being obtained for Au electrodes. The main advantage of this method, when compared with traditional and rapid thermal annealing, is that the thermal treatment is localized in a small region, thus allowing the processing of circuits composed of different materials, whereby each process can be individually controlled. (AU)

• Processo FAPESP: 09/14600-4 - Reatores e sensores de gases baseados em nanotubos de carbono decorados com nanopartículas
• Beneficiário: Raluca Savu
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado