Optical Aperture Metrology

AST’s advanced VCSEL metrology capability precisely measures and reports the “Optical Aperture” (OA) diameter, roundness and angle of the feature if it is elongated (oval) relative to the primary wafer global fiducial reference frame.  These state-of-the-art turnkey metrology systems provide the required accuracy and stability to perform these critical VCSEL measurements using advanced IR imaging technology.

Imaging can be performed 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 critical VCSEL measurements including CD-Overlay .  AST’s ScopeViewer software provides the capability to create a program (script) that can automatically perform the required metrology functions.


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.   These systems provide high-performance and precision to capture high-resolution image of the VCSEL aperture along with performing other critical measurements using AST’s advanced ScopeViewer metrology software suite. 

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 output 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 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.