Patent ID: 7889908

Claim:
A method for measuring a shape of a semiconductor pattern on a semiconductor wafer in a scanning electron microscopy (SEM) apparatus including an electro-optical system to irradiate electron beams onto the semiconductor wafer, the method comprising: acquiring a tilt image of the semiconductor pattern on the semiconductor wafer by observing the semiconductor pattern by scanning the electron beams onto the semiconductor wafer, via the electro-optical system; estimating a sectional shape of the semiconductor pattern from the acquired image of the semiconductor pattern, the sectional shape being a three-dimensional (3D) shape; calculating a shape index value correlated with the estimated sectional shape of the semiconductor pattern; determining a range of a correction area in the estimated sectional shape of the semiconductor pattern by segmenting an area of the estimated sectional shape using information of the calculated shape index value; fitting a curve or a curved surface to a bottom corner of the estimated sectional shape within the range of the correction area in the estimated sectional shape; and correcting the estimated sectional shape of the semiconductor pattern from the acquired image based on the curve or curved surface fitted to the bottom corner of the estimated sectional shape within the range of the correction area.