Water-assisted, electron-beam induced activation of carbon nanotube catalyst supports for mask-less, resist-free patterning

The promise of carbon nanotube (CNT)-based technology has driven colossal research efforts for the past three decades. Integration of CNTs onto functional devices often involves the use of time-consuming and laborious patterning techniques to obtain spatially selective growth. In this manuscript, we present a single-step route for CNT forest growth in patterned areas using a novel catalyst support activation process which does not require the use of masks, resists or stencils. The process uses an electron-beam (e-beam) in the presence of water vapor to activate a catalyst support at select locations, on which CNT forests can grow selectively when exposed to the CNT catalyst and precursor. The process, therefore referred to as e-beam chemistry, modifies the support stoichiometry and surface roughness using a radiolysis-driven mechanism to yield catalytically active patterns on an otherwise inactive catalyst support. Because of its simplicity and effectiveness, the presented technique holds great promise in producing high fidelity, chemically-selective patterns.