On the Performance of Carbon Nanotubes in Extreme Conditions and in the Presence of Microwaves
Abstract
Using van der Pauw and microwave surface resistance measurements, a series of temperature-dependent data sets from carbon nanotube (CNT) thin films have been measured. The test structures were fabricated using photolithography, E-beam evaporation, and a novel CNT network deposition technique. The sheet resistance and resistivity of each sample were recorded at temperatures ranging from 0 60 C with test currents ranging from 100 nA to 100 A. These values demonstrated excellent linearity, with no dependence on currents. At room temperature, the sheet resistance yielded a negative temperature coefficient (of approximately 900 ppm/ C). Our objective is to analyze the effect that DC and microwave currents have on CNT thin films using a two-point measurement technique on Corbino discs and in the presence of microwaves (8 12 GHz) to determine at which temperatures a CNT thin film performs best and identify the ideal temperature range in which a CNT microchip yields the maximized sheet resistance. The results counter the trend found by the four-point measurements; a positive temperature coefficient was observed. This observation indicates the temperature coefficient of the material is actually dependent on the size of the sample tested.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2013
- Accession Number
- ADA572622
Entities
People
- Julia B. Doggett
- Ryan C. Toonen
Organizations
- United States Army Research Laboratory