Nanostructuring of substrate such as metal/semiconductor/its alloy, by direct laser ablation, comprises irradiating the substrate surface with spatially distributed laser intensity patterns, and coating the surface with polymer layer

摘要

The nanostructuring of a substrate (10) such as metal or semiconductor or its alloy by direct laser ablation, comprises irradiating the surface of the substrate with spatially distributed pulsed laser intensity pattern (14) with a high intensity region, in which a destruction threshold of the substrate surface is exceeded and with a low intensity region, in which the destruction threshold of the substrate surface is not exceeded. The substrate surface is coated with a hardened polymer layer (12) that is transparent for laser light. The nanostructuring of a substrate (10) such as metal or semiconductor or its alloy by direct laser ablation, comprises irradiating the surface of the substrate with spatially distributed pulsed laser intensity pattern (14) with a high intensity region, in which a destruction threshold of the substrate surface is exceeded and with a low intensity region, in which the destruction threshold of the substrate surface is not exceeded. The substrate surface is coated with a hardened polymer layer (12) that is transparent for laser light. An interval of two closest neighboring high intensity regions is less than one micrometer. The refractive index of the polymer layer is larger than the refractive index of the air. The thickness of the polymer layer is less than a micrometer. The laser intensity pattern is produced by interfering superposition of laser beams or portion of laser beam. The wavelength of the intensity pattern lies in the ultraviolet spectral region and the pulse length of the intensity pattern is few hundred femtoseconds or below hundred. The energy density in the high intensity region of the intensity pattern is 100 mJ/cm 2>. The substrate is a metal or semiconductor or its alloy.