Patent ID: 9201027
Filing Date: 2015-12-01
Classification: G01N,G03F,H01L

Abstract:
1. A method of evaluating a semiconductor wafer, the method comprising: recording a first intensity of a reflection of an X-ray beam onto a test area on a substrate of the semiconductor wafer at a detector, the recording occurring as the X-ray beam is projected substantially perpendicular to a length of a first plurality of expected, periodic structures in the test area and at an angle defined between the X-ray beam and a surface of the test area; recording a plurality of second intensities of the reflection of the X-ray beam onto the test area as the X-ray beam is projected onto the test area at a plurality of increments from the angle; and identifying intensity peaks in the recordings of the first and second intensities and, based on positions of the intensity peaks relative to the test area, determining a peak spacing between two adjacent peaks of the plurality of expected, periodic structures.