Interaction of intense nanosecond pulses of extreme ultraviolet (EUV) and the EUV induced plasmas with solids

Extreme ultraviolet (EUV) is the ionizing radiation strongly absorbed by any atoms or molecules. Laser produced plasmas (LPP) are intense sources of such radiation. The LPP EUV sources developed in Institute of Optoelectronics were used for EUV induced microprocessing of materials. The radiation pulses with the fluence up to 0.5 J/cm2 were delivered to the interaction region. Additionally a reactive gas could be injected in a vicinity of the exposed material. In such case the surface was simultaneously exposed to the EUV photons and reactive plasmas. Irradiation of solid samples resulted in melting of a thin near-surface layer, its ablation or even conversion to cold plasmas. In case of organic polymers, fragmentation of molecules, took place. In case of inorganic solids, a near surface layer was heated up to a high temperature exceeding melting point. In most cases micro- or nanostructures were created. In case of simultaneous EUV and the EUV induced plasma treatment, additional atoms could be incorporated into the molecular structure of the exposed material, or reactive etching took place.