We obtained germanium dioxide (GeO 2) whiskers in bulk quantity by ablating a germanium
target at 820° C with a pulsed KrF excimer laser in an argon atmosphere. Most of the GeO 2
whiskers were smooth and straight with hexagonal or triangular, or quadrilateral cross
sections while some of them had a bamboo-shoot-shaped form. Results of scanning
electron microscopy, transmission electron microscopy, and x-ray diffraction showed that the
whiskers are hexagonal crystalline GeO 2.