Patent ID: 10177049

Abstract:
Techniques for measuring and testing a semiconductor wafer during semiconductor device fabrication include designating a test area on the top surface of the wafer and etching a first rectangular trench and a second rectangular trench on the top surface of the wafer in the test area. The trenches are oriented such that a length of the first trench is perpendicular to a length of the second trench, and positioned such that the length of the first trench, if extended, intersects the length of the second trench. A silicon-germanium compound is deposited into the first trench and the second trench, and a test pad is removed from the test area of the wafer. The test pad includes a side surface where both the first trench and the second trench are exposed. The side surface of the test pad is scanned with a transmission electron microscope to take measurements of the silicon-germanium.