NIST Develops Advanced Metrology Technique for Nanoscale Pattern Measurement
The National Institute of Standards and Technology (NIST) has developed a new metrology technique called CD-SAXS (Critical Dimension Small Angle X-ray Scattering) to measure Line Width Roughness (LWR) in nanoscale semiconductor patterns with high accuracy. LWR is a critical parameter in semiconductor manufacturing that affects device performance and yield.
NIST collaborated with Intel and Sematech to design and fabricate test patterns with controlled LWR. These patterns were measured using both synchrotron sources and NIST’s lab scale CD-SAXS prototype, which uses a high-energy rotating anode Mo X-ray tube source. While synchrotron sources provide higher flux, NIST’s lab scale prototype demonstrates that high-quality data can be collected with lower flux sources.
Benchmarking against the industry standard CD-SEM (scanning electron microscope) showed excellent agreement between CD-SAXS and CD-SEM line width measurements. However, CD-SEM showed a bias towards the bottom width of features in top-down images. NIST’s CD-SAXS methods show great potential for nanoscale pattern metrology, with plans to connect lab scale CD-SAXS equipment to a developmental compact X-ray synchrotron source for further development and industrial application.
Source: https://www.nist.gov/programs-projects/dimensional-metrology-nanoscale-patterns
Keywords: quantum sensing, quantum metrology, quantum devices
