Nanophotonics Ag

Other

Matthias Eberhardt

Michael Abraham

Oliver Depner

A micropolarimeter and ellipsometer for obtaining complete optical information of superficially illuminated specimens. A compact construction is designed to facilitate their use. To obtain the simultaneous surface measurement of all optical information from a specimen, the retarder of the micropolarimeter consists of a one-piece retarder array with at least one pixel group, in which the major axis orientations of the individual pixels are distributed over an angular range of 360&deg;. This micropolarimeter can be integrated into the reflected light microscope of an ellipsometer. The result is a compact measurement unit.

Micropolarimeter and ellipsometer

The invention concerns a micropolarimeter comprising an analyzer (,) and a detector (,) located past the analyzer in the direction of radiation and presenting a number of segments N,which is higher than or equal to 3 (,). The invention seeks to provide a micropolarimeter with no moving parts, with a high polarization index, for use for polychromatic light, so small that it can detect the ray of common lasers in one single measurement step without it being necessary to enlarge it, and capable of being converted in a simple manner into a complete Stokesmeter. To that end, the analyzer (,) consists of a radially symmetrical flat disk (,) produced in a polarizing material with which the polarization rests on absorption effects inside said material, the surface of the analyzer (,) being greater than or equal to the surface of the detector segments (,)

Micropolarimeter

Normally, repeated calibration measurements are necessary for the adjustment of the sample and ellipsometer. To achieve an automatic relative adjustment, a sample position detection system that can be adjusted in relation to the ellipsometer and locked in is assigned to the ellipsometer, and where the detection system is connected to an adjusting system that affects the sample table and/or the entire system detection system/ellipsometer. The method for automatic relative adjustment is provided for, that by initially using one sample, the system sample/ellipsometer is adjusted via the symmetry of the detector signal of the ellipsometer, and that the sample position detection system is adjusted and subsequently locked in with the ellipsometer. With all subsequent samples, a relative adjustment of sample and ellipsometer detection system is performed using the signals of the detection system. In particular, the measurements can be performed without moving the sample itself because the adjustment can also be carried out through a single movement of the ellipsometer detection system.

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Lörzweiler, Germany

Matthias Eberhardt