Abstract: Arrays of sharp spikes have been formed on the surface of silicon by cumulative femtosecond laser pulse irradiation in an SF6 atmosphere. The absorbance of light by silicon with a microstructured surface is approximately 90% throughout the region from the ultraviolet (250nm) to the near infrared (2500nm). The sharp spikes formed on the surface using femtosecond laser－chemical etching are also good field－emitters. With its amazing optoelectronic properties, surface microstructured silicon shows promising potential applications in the manufacture of solar cells, optoelectronic detectors, flat displays and so forth.