Device for measuring characteristics of sample by ellipsometry, comprises reflection or refraction of number of incident rays forming incident beam interacting with material of sample

摘要

The detection device includes a means of measuring the characteristics of individual polarization of a number of resultant rays, contained in a number of different incidence planes, without changing the polarization of the incident beam and the direction of analysis of the analyzer. Each reflected or refracted ray is called a resultant ray and each resultant ray forms with its original incident ray an incidence plane. The device includes a polarizer determining a fixed and uniform polarization in the incident beam; a focussing device converging the incident beam onto the insulated analysis point; an analyzer containing analysis instructions w.r.t which the polarization of the resultant rays are analyzed, and a detection device detecting the polarization characteristics of the analyzed resultant rays. The detection device is made of a number of detectors forming a multi-channel detector to measure simultaneously the energy of a number of resultant rays received in the analyzer. The detection device also contains a linear polarizer along a uniform set analysis direction, which modifies the energy of the resultant rays which it receives as a function of their individual polarization characteristics. The detection device contains a matrix of independent detectors measuring the individual energy of a number of resultant rays or groups of resultant rays: the measurement is transmitted to the means of calculation for treatment or comparison. The focussing device converges the beam onto the sample at the analysis point at an angle fixed to the normal axis or near to the direction normal to the surface of the sample at the analysis point. The detection device contains detectors of which at least some have a different spectral sensitivity and measure the resultant rays from an incident light beam containing a number of wavelengths. The device includes a Fabry-Perot interferometer positioned in the optical path to act on the beams so it transmits a selection of angles or spectra. An independent claim is included for measuring the characteristics of a sample using the above device.