Precise Structuring Using Femtosecond Lasers

Abstract

Femtosecond (fs) lasers are perfect laser sources for material processing when highest accuracy and smallest structure sizes are required. Due to the ultrashort interaction time and the high peak power the process is generally characterized by the absence of heat diffusion and, consequently, molten layers. Moreover, the process is nearly independent of the material and recent results demonstrate the possibility to ablate material with sub-μm accuracy or even nm dimension while maintaining an outstanding reproducibility. Also, certain technically important materials like metals with high heat conductivity, semiconductors, and dielectrics with high transparency in the visible and uv can be processed by fs laser pulses which have been unable to machine so far with conventional laser radiation. In contrast to longer laser pulses, the absorption and ablation process can be described in a more simple way resulting in a higher reproducibility and controlability of the process.
Besides the microelectronics industry there are numerous potential applications in the field of automotive supplier industry, medicine technology and finally telecommunication.