3D periodic structures grown on silicon by radiation of a pulsed Nd: YAG laser and their field emission properties

Periodic three-dimensional structures were successfully grown on single crystal Si wafers either bare or Au-covered under their exposure to a pulsed radiation of a Nd:YAG laser in vacuum. The structures protrude above the initial wafer surface for 10 mm while their spatial period is about 70 mm. The coupling of the laser radiation to Si surface is related to the thermal non-linear absorption of the near band gap radiation. The structures exhibit an efficient field emission with an average emission current of 5 mA/cm2 and is sensitive to the post-treatment of samples. The drawbacks of the emission current densities are discussed.