Arrangement and method for extending the measuring range of Nomarski microscopes

摘要

The invention relates to an arrangement and a method for extending the measuring range of Nomarski microscopes, in which polarised illuminating light is split into two wave fronts by at least one element (Nomarksi prism 4) which produces a shear component, the wave fronts are then passed through an imaging optical element such that illuminating light impinges on the specimen (sample) (7), is reflected from there, the imaging optical element and the element which produces the shear component being passed through and, at the same time, the two reflected wave fronts being superposed and made to interfere by means of an analyser (2). The invention is characterised in that via rotation of the specimen (7) in an x-y plane about a y axis about an angular amount DELTA PSI and the carrying out of in each case one measurement in the different angular positions PSI 1 and PSI 2 light (intensities I1, I2) is registered by a receiver (matrix receiver 1) and the inclination angles PSI (x, y) of the surface elements are determined, from the signals, over the extended inclination angle range (e.g.: n-4, ..., n0, ..., n+4). By means of the invention, inclination angles PSI of surface elements can be determined unambiguously in a relatively large interval, this corresponding to an extension of the measuring range of the Nomarski microscope by, for example, the factor 5. <IMAGE>