Next generation of a linear chirped slope profile fabricated by plasma jet machining

Plasma Jet Machining is an established process in ultra-precision surface manufacturing. Removal of several nanometers up to millimeters can be achieved using the atmospheric pressure reactive plasma jet as a non-mechanical tool. Surface form measuring techniques have to be improved equally, to further enhance the deterministic machining. Exact knowledge of the instrument transfer function is necessary to distinguish measurement artefacts and reliable measurement results. Precise sinusoidal surface structures prepared by plasma jet etching can be used as calibration elements to determine the instrument transfer function, e.g. slope-measuring devices like Nanometer Optical component measuring Machine (NOM). The steps for manufacturing such calibration elements including theoretical considerations, adjustment of the plasma jet parameters and implementations on different substrates are presented. Finally, a chirped sinusoidal structure on a singlecrystalline silicon slab is fabricated.