The MetroShot-101 sensor uses patent pending infrared (lR) interferometry technique, which provides a direct and accurate substrate stress measurement, thickness measurement and thickness variation (TTV), and defect inspection of thick to ultra-thin wafers for in-situ grinding, etching and deposition applications. The Fast MetroShot-101 also provides measurements of total thickness of the wafer, including substrate thickness and the patterned height thickness. It can measure film stress and wafer bow measurements alongside with 2D and 3D mapping. The new “MetroShot-101” with its precision optics and scanner is designed for R&D and production of next generation devices in the semiconductor I-V, solar. MEMS, and data storage, and FPD industries. Frequently the tool is used for resolving issues such as film cracks, delamination, hillocks and void formations.