Postdoctoral Researcher in Data-driven X-ray Nanoimaging for Semiconductor Metrology

About the role

The newly established Laboratory for Nanoscale X-ray Metrology at EPFL is looking for a postdoctoral researcher to turn the idea of comparing chip structures against their known design into a working method. The position focuses on high-throughput imaging of static structural defects; the companion position covers time-resolved imaging of dynamic processes. Each postdoc leads their own independent research direction within the SNSF Starting Grant project NEXUS-3D, based at the Swiss Light Source synchrotron near Villigen.

Key responsibilities

• Develop an acquisition and reconstruction framework that uses the known geometry, composition and layout regularity of semiconductor devices as prior information to detect deeply buried defects from the fewest possible X-ray measurements.
• Reconstruct each projection from thousands of diffraction patterns, then build volumes from projections measured at many rotation angles.
• Investigate the minimum number of diffraction patterns and projections needed to identify a defect, whether defects can be detected from diffraction patterns alone, and how to best use known design information.
• Focus primarily on algorithm development, demonstrated at synchrotron experiments, starting with existing experimental datasets and extending the reconstruction pipeline.
• Perform experiments at the cSAXS beamline of the Swiss Light Source and other synchrotrons worldwide.

Required profile

• PhD in physics, engineering, computer science or a related field.
• Excellent written and oral communication skills in English.
• Preferred: coherent diffractive imaging (ptychography), sparse sensing, optimization or Bayesian experimental design, machine learning for imaging, synchrotron experience, or semiconductor metrology.

Required skills

• Strong scientific programming in Python and experience with GPU processing of large-scale datasets.
• Experience with inverse problems and 3D reconstruction methods for tomography, laminography or a closely related modality.

What we offer

• A fully funded, two-year postdoctoral position (renewable annually) with contracts issued for one year.
• Close mentorship and support for professional development, including summer schools, international conferences and experiments at synchrotrons.

Applications are submitted online through the EPFL platform as a single PDF containing a cover letter, a detailed CV and a research statement, plus three referees. Applications are reviewed on a rolling basis; the expected start date is flexible.