2013 R&D 100 Winner
Metrology tools are judged according to their accuracy, cost, speed and destructiveness to the sample. Transmission electron microscopes (TEMs), the most accurate instruments available, can be destructive, slow and expensive. Scanning technologies, meanwhile, sacrifice accuracy for speed and sample preservation and optical methods have accuracy challenges related to scattered light. At NIST, scientists have developed the first technology to effectively combine the best aspects of two or more different measurement techniques into a monolithic result, reducing measurement uncertainty through the application of model-based metrology. Quantitative Hybrid Metrology (QHM) relies on both physics-based and Bayesian statistics-based models to provide basis of comparison to the intensity pattern from the target of interest. Generating parametric values from both instrumentation and models, QHM effectively combines methods such as optical critical dimension metrology and scanning electron microscopy to yield a potential three-fold improvement in accuracy.

Metrology tool


Development Team

The Quantitative Hybrid Metrology (QHM) Development Team from NIST
Bryan M. Barnes, Principal Developer
Richard M. Silver, Principal Developer
Nien Fan Zhang, Principal Developer
Hui Zhou