AUTOMATED INLINE INSPECTION AND METROLOGY USING SHADOW-GRAM IMAGES

摘要

Shadow-grams are used for edge inspection and metrology of a stacked wafer. The system includes a light source that directs collimated light at an edge of the stacked wafer, a detector opposite the light source, and a controller connected to the detector. The stacked wafer can rotate with respect to the light source. The controller analyzes a shadow-gram image of the edge of the stacked wafer. Measurements of a silhouette of the stacked wafer in the shadow-gram image are compared to predetermined measurements. Multiple shadow-gram images at different points along the edge of the stacked wafer can be aggregated and analyzed.

主权项

1. A system comprising:
a light source configured to direct collimated light at an edge of a stacked wafer; a detector disposed opposite the light source, wherein the detector is configured to acquire a shadow-gram image of the edge of the stacked wafer; and a controller operatively connected to the detector, wherein the controller is configured to:
receive the shadow-gram image; andcompare characteristics of the shadow-gram image with predetermined measurements to inspect an edge profile of the stacked wafer.