Laser Ionisation Spectroscope

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Laser-induced ionisation spectroscopy is one of the oldest laser applications. It allows the analysis and determination of the chemical composition of solid, liquid and gaseous substances without special sample preparation; further, it has a low detection limit. This makes the method a powerful and robust tool in surface analysis. In addition, novel approaches of signal evaluation enable the measurement of lowest chemical changes and the quantification of main components and even trace elements without any calibration. As the excitation is performed by means of focused laser radiation, a high lateral resolution and depth resolution, e.g. for three-dimensional element mapping, can be easily realised. By measurements in defined environments with respect to gas composition and pressure, disturbing plasma-induced effects such as self-absorption of spectral lines can be eliminated, resulting in an increased evaluation accuracy. All these unique selling points of a laser ionisation spectroscope allow the analysis of a wide range of materials or phenomena caused by surface modification. For example, specifically induced stoichiometric changes can be detected and quantified. The design of the device as a closed system of laser safety class 1 allows a fast and safe analysis of large sample quantities. Due to these measuring principle-specific advantages and unique selling points, the required laser ionisation spectroscope represents an essential extension of the analysis possibilities in the research focus laser and plasma technology at the HAWK. In most cases, the detection of smallest chemical changes on surfaces of a multitude of different sample materials is necessary. Thus, the proposed system contributes considerably to the understanding of interaction mechanisms in the individual research fields of the research group.