Enhanced Adhesion between Carbon Nanotubes and Substrate Surfaces by Low-temperature Annealing

Abstract

We enhanced the adhesion forces between carbon nanotubes (CNTs) and the substrate surface by using a low-temperature annealing process at 180 degrees C for 300 s to protect the CNTs throughout the processes in photolithography for fabricating CNT-based devices, especially ion and bio sensors which are always exposed to liquids. The adhesion force was tested by using the adhesion durability test of soaking the fabricated CNT field effect transistors (CNT-FETs) in de-ionized water at room temperature for 300 s, and the adsorption quantities of CNTs were analyzed by using I - V measurements on the CNT-FETs before and after each adhesion durability test. The conductance change of the CNT-FETs fabricated with the annealing process was considerably decreased by more than a factor of 10(5) compared to that without the annealing process, implying that CNTs adhere much more strongly to the substrate after the annealing process.