Laser-Assisted Process Grows Sharp Tips

Sharp tips coated with diamondlike carbon have potential applications in field-emitter arrays, scanning spreading resistance microscopy and nanofabrication techniques. Reporting in the Aug. 9 issue of Applied Physics Letters, researchers at the University of Nebraska-Lincoln and National University of Singapore describe a laser-assisted deposition method for the fabrication of the tips. In this approach, tungsten wires are irradiated with a 248-nm pulse from a KrF excimer laser as they are dipped in a benzene solution. The laser generates a locally confined optical field around the apex of the tip of the wire, in which region a diamondlike carbon film can form. Courtesy of Yongfeng Lu, University of Nebraska-Lincoln.