Hseb Dresden Gmbh

Unity Semiconductor Corporation

Ralf Langhans

Bernd Srocka

Christine Schmidt

A method for optically measuring height profiles of surfaces, in which an image of the height profile is recorded using an optical recording system, is characterized in that the image is a differential interference contrast image and height gradients within the height profile are represented by intensity gradients, which are quantitatively or qualitatively evaluatable. The surfaces can have structures having a defined profile, in which intensity gradients in the differential interference contrast image, which assume, within a specified tolerance and within a specified range, a value which deviates from a predetermined value or assume a selected value from within a specified tolerance and within a specified range, indicate a defect.

Measurement method for height profiles of surfaces using a differential interference contrast image

An arrangement for optically detecting buried layers of flat objects having a plurality of layers, in particular wafers, containing a radiation source for illuminating the surface of the object at an angle; a polarization filter arranged in the beam path; and a detector for detecting radiation reflected by the surface of the object or transmitted by the object; is characterized in that that layer of the object which is closest to the radiation source at least partially transmits the radiation from the radiation source; the polarization filter transmits only radiation which is polarized parallel to the plane of incidence; and the surface of the object is illuminated at the Brewster angle. The surface of the object is preferably illuminated with unpolarized radiation and the polarization filter is arranged in the beam path between the surface of the object and the detector.

Method for detecting buried layers

The invention relates to an arrangement for analyzing an at least partially reflective surface of a wafer or other objects, containing a holder for holding the object; an inspection arrangement arranged at a distance in the region in front of the surface to be analyzed; and a measurement arrangement for determining the distance and/or inclination of the surface for the inspection arrangement; characterized be a radiation source, the radiation of which is directed towards the surface to be analyzed at an angle; and a spatially resolving detector for receiving the radiation from the radiation source that is reflected from the surface to be analyzed, wherein the radiation source and the detector are arranged outside the region necessary for the inspection between the inspection arrangement and the surface to be analyzed.

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Dresden, Germany

Ralf Langhans