Apparatus and method for three dimensional inspection of wafer saw marks

摘要

An apparatus (1) and a method for the three dimensional inspection of saw marks (2) on at least one surface (3) of a wafer (4) are disclosed. At least one camera (6) is required to capture an image of the entire surface (3) of the wafer (4). At least one line projector (8) provides a light bundle (5), centered about a central beam axis (9). The line projector (8) is arranged such that the central beam axis (9) is at an acute angle (α) with regard to the plane (P) of the wafer (4). A line shifter (12) is positioned in the light bundle (5) between each line projector (8) and the surface (3) of the wafer (4). A frame grabber (14) and an image processor (16) are used to synchronize and coordinate the image capture and the position of the pattern (20) of lines (22) on the front side (3F) and/or the back side (3B) of the wafer (4).

主权项

1. An apparatus for inspection comprising:
at least one camera defining a field of view, wherein the field of view is configured such that at least a portion of a surface of the wafer is captured; at least one light source; at least one line projector configured to provide a light bundle centered about a central beam axis, wherein the at least one line projector is arranged such that the central beam axis is oriented at an acute angle with respect to a plane of the wafer, wherein the at least one light source is configured to provide light to the at least one line projector, wherein the at least one line projector is configured to project a pattern of a plurality of lines onto at least one of a front side or a back side of the wafer; at least one line shifter positioned in the light bundle between the at least one line projector and the surface of the wafer; a frame grabber; and an image processor, wherein image capture of the at least one of the front side or the back side of the wafer is synchronized by the frame grabber in coordination with the position of the pattern of lines on the at least one of the front side of the wafer or the back side of the wafer, wherein the image processor is configured to perform a three-dimensional inspection of one or more saw marks of the wafer.