Encapsulation of electrical contacts for suspended single‐walled carbon nanotubes by atomic layer deposition

Abstract

Abstract We show encapsulation of electrical contacts to freestanding single‐walled carbon nanotubes (SWNTs) by selective nucleation of Al 2 O 3 from atomic layer deposition (ALD). Passivating electrical contacts is often required to prevent degradation of devices, and for chemical sensing it can separate sensing mechanisms either dedicated to metal contact regions or to SWNT channels. As ALD Al 2 O 3 does not grow on defect‐free SWNTs, Al 2 O 3 is selectively deposited on contacts to suspended SWNTs. TEM imaging on micromachined structures enables to investigate the mask‐less fabricated encapsulation. magnified image Surface selective nucleation of Al 2 O 3 during ALD encapsulates electrical contacts to suspended SWNTs while leaving pristine sections unaffected.