| 摘要 |
Determination of the height difference between a first reference point and a second reference point, at least one of the two reference points lying on a semiconductor chip, which is mounted on a substrate, comprises the steps A) recording a first image from a first direction, which runs diagonally to the surface of the substrate at a predetermined angle α2, the substrate and the semiconductor chip being illuminated from a second direction which runs diagonally to the surface of the substrate at a predetermined angle α3, a telecentric optics being located in the beam path, B) recording a second image from the second direction, the substrate and the semiconductor chip being illuminated from the first direction, either the cited telecentric optics or a further telecentric optics being located in the beam path, C) ascertaining a first coordinate of the position of the first reference point and a first coordinate of the position of the second reference point in the first image and determining a first difference between these two coordinates, D) ascertaining a first coordinate of the position of the first reference point and a first coordinate of the position of the second reference point in the second image and determining a second difference between these two coordinates, and E) calculating the height difference from the first difference and the second difference.
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