Suspended nanowire bridge fabricated by focused ion beam as a hydrogen sensor

초록

A highly sensitive hydrogen sensor based on suspended and functionalized single tungsten nanowire is presented. The nanowire sensing structure is formed by Focused Ion Beam-Chemical Vapor Deposition on the batch-fabricated microelectrodes. The tungsten nanowire measures 10 mu m in length and 150nm in diameter, and is suspended 50 mu m above the wafer substrate connecting two microelectrodes. The nanowire is then functionalized by Pd-Pt metallization to be sensitive to hydrogen gas. The experimentally characterized hydrogen sensor shows 11.52% of resistance increase to the exposure to 10000ppm (1%) hydrogen gas and 99% nitrogen gas mixture at room temperature and atmospheric pressure. The lowest hydrogen concentration we measured is 10ppm with 0.58% corresponding resistance increase.

키워드