Wafer Metrology

 

It is important to ensure that predetermined wafer specifications are consistently adhered to during the manufacturing process. Measurements are therefore taken, which include the width of the lines on the chips, the thickness of the layers, the surface profile of the layers, and some electrical properties of the layers.

 

Three main segments of wafer metrology include Optical Metrology, Thin-Film Metrology and Critical Dimension Scanning Electron Microscopes (CD-SEM). Optical Metrology involves using optics to verify certain critical dimensions of the chip. Thin-Film Metrology analyses the surface of a film on the wafer. CD-SEM measures the circuit lines or features of the chip.