CD Overlay / Metrology

AST’s advanced metrology platforms can be configured to image wafers and dies at NIR (visible to 1050nm) through SWIR (900nm – 1700nm) enabling measurements to be taken at the optimum wavelength that provides the best image quality for executing CD overlay of bonded wafers and die to confirm alignment, detection of cracks & delamination, as well as other metrology applications.  

Imaging in the visible wavelength that can be combined interferometric options such as differential interference contrast (DIC) can be integrated based on providing the optimum imaging solution.  Additional sensor technology is supported to enable enhanced measurement capability to be integrated based on meeting specific metrology requirements. 

These state-of-the-art turnkey metrology systems provide the required accuracy and stability to perform these critical measurements using advanced positioning / motion control technology, IR and visible imaging options, and high-speed image capture and processing capability.  

Automated wafer and part-handling options are available for 150mm, 200mm, and 300mm wafers.  Product solutions range from fully-integrated high-performance turnkey systems to integrated workstations with automated wafer loader.

CD Overlay / Metrology Products

AST 300 Metrology System

Advanced Metrology System


The AST-300 integrates best-in-class precision positioning capability within a highly flexible system that provides an optimum platform for integrating AST’s advanced imaging systems.   The ATS-300 platform provides a highly flexible, high-performance system platform capable of capturing high-resolution images on wafers, dies, & MEMS devices.  AST’s advanced ScopeViewer metrology software suite provide a feature rich package that can be scripted to perform fully-automated measurement sequences with a high degree of precision. 

AST can also integrate other sensor technology such as Spectrophotometers, Ellipsometers, Profilometers, etc. to combine multiple tool metrology tasks into a single system, reducing operation and tool counts and handling requirements. 

Data can be outputted through SECS GEM or other factory information systems enabling report generation, process control, and other factory, process, and product metrics to be tracked. 

Optional integrated wafer handler with pre-align and OCR provides the capability to add automated load / unload of wafers / tape frames from a cassette.


All of our CD overlay and Metrology systems can be fully customized to meet your requirements. If you have questions about our product offerings or capabilities, please contact us for more information.