A microarray approach for optimizing localized deposition of carbon nanotubes using microhotplate arrays

A 340-element array of microhotplates was used to characterize the chemical vapour deposition growth of carbon nanotubes and nanofibres under a variety of process conditions. One dimension of the 17 by 20 element array was used to vary the thickness of a Ni catalyst layer. The second dimension was used for temperature control. Growth took place in an ambient temperature gas flow system, with processes only occurring on activated heaters. This allowed different process sequences to be defined on different columns of the array. Four parameters were varied: pre-anneal temperature of the catalyst, growth temperature of the carbon nanostructures, growth pressure, and growth time. Scanning electron microscope images of each array element revealed trends in microstructure as these parameters, together with the catalyst thickness, were varied.