Highly-ordered suspended nanowire array for self-heating type gas sensors

Abstract

The operating temperature of electrical chemo-resistive gas sensors is directly related to performance of the devices. Self-heating type gas sensors provide the required operating temperature by utilizing Joule heating effect arising in the sensing material for devices to work in their optimum environment. This paper reports a highly-ordered suspended nanowire array as an adequate structure for self-heating type gas sensors. As a first demonstration of the proposed structure, a hydrogen gas sensor with palladium nanowire array was fabricated and evaluated. Estimated temperature through FEM simulation verifies the excellent self-heating capability of the fabricated device. When the performance as a hydrogen gas sensor was evaluated, remarkable enhancement in performance could be achieved as the operating temperature elevated through self-heating.