Ultrafast, Multiplexed EUV Scatterometry for Device Metrology in the Ångström and Quantum Technology Eras
PhD - Leuven | Just now
The physical limitations of continued lateral scaling of transistors have resulted in a paradigm shift in the nanoelectronics industry, whereby transistors of future technology nodes will employ vertically integrated device architectures. The vertical integration of transistors, particularly complimentary field effect transistors (CFET), pose new challenges in not only production, but also in the advanced meteorology necessary to measure structure-function relationships in complex and heterogenous environments with nanoscale accuracy and precision. In the wake of this grand metrology challenge, short-wavelength scatterometry employing extreme ultraviolet (EUV) light has emerged a powerful, non-destructive, and non-contact technique for accurately extracting material parameters in a complex, multidimensional space [1, 2]. In particular, coherent, femtosecond EUV light from high-harmonic generation (HHG) has shown promise for characterizing nanosheet device stacks [1] as well as EUV masks [2] with high precision, all from an accessible, tabletop system. Despite these advances, the advantages of HHG-based EUV sources (e.g., high coherence, ultrashort pulses, and in-situ polarization and beam shaping) have been largely unexplored, despite recent publications suggesting polarization and beam control, coupled with ultrafast time-resolved measurements, can yield enhanced metrology capabilities [3-6]. These recent works show that nanoscale dynamical properties such as elastic modulus, density variations, and thermal/charge carrier transport can be extracted, although they have yet to be combined with the nanoscale precision afforded by scatterometry.
The objective of this PhD project is to develop and deploy time-resolved, multiplexed EUV scatterometry to characterize dynamic structure-function relationships in advanced nanoelectronic devices and structures, with the goal of achieving a breakthrough metrology to support the Ångström and Quantum technology nodes. This ambitious project will be supported by imec’s advanced LAB and FAB infrastructure, which is composed of advanced production, metrology, and material characterization of semiconductor devices. In particular, unique toolsets such as imec’s AttoLab, an ultrafast spectroscopic and materials characterization lab, will be central to measuring the ultrafast scatterometry signals from these devices and materials. The breakthrough scatterometry methods developed in this project will be supported by simulations of the dynamic optical response, as well as 2D/3D inverse modelling of scatter patterns to reconstruct the nanoscale geometry. You will work closely with experts in materials characterization, metrology, device fabrication and characterization, and modelling to provide a wholistic understanding of dynamical properties, and their link to composition, of nanoelectronic devices and materials.
As a PhD candidate within imec's Materials and Component Analysis department, you will,
- Develop and execute time-resolved EUV scatterometry measurements and inverse modelling to reconstruct geometric and material properties of nanodevices
- Conduct a comprehensive LAB- and FAB-based characterization of advanced nano structures and devices produced in imec’s pilot lines.
- Develop a strong technical skillset for diverse characterization techniques (e.g., AFM, TEM, X-ray diffraction/reflection, etc.).
- Correlate structural, compositional, and electrical properties to ultrafast material properties.
- Critically analyze scatterometry data with respect to material and process variation.
- Presenting your findings at conferences, internal meetings, and gaining exposure to key players in the global semiconductor community.
- Assist in teaching labs sessions and/or monitoring examinations of relevant courses at the bachelor’s and master’s level at KU Leuven (<5% of total time).
[1] Porter, C., et al. “Soft x-ray: novel metrology for 3D profilometry and device pitch overlay”, Proc. SPIE 12496, Metrology, Inspection, and Process Control XXXVII, 124961I (2023). https://doi.org/10.1117/12.2658495
[2] Vitaly Krasnov, et al. “Table-top HHG EUV scatterometry for roughness and structural parameters evaluation in nano-stacks”, EPJ Web Conf. 335 01019 (2025). https://doi.org/ 10.1051/epjconf/202533501019
[3] Capotondi, F., et al. “Time-Domain Extreme-Ultraviolet Diffuse Scattering Spectroscopy of Nanoscale Surface Phonons” Phys. Rev. Lett. 135, 266101 (2025). https://doi.org/10.1103/dq8w-62bm
[4] Karl, R., et al. “Full-field imaging of thermal and acoustic dynamics in an individual nanostructure using tabletop high harmonic beams” Sci. Adv. 4, eaau4295 (2018). https://doi.org/10.1126/sciadv.aau4295
[5] Frazer, T., et al. “Full characterization of ultrathin 5-nm low-𝑘 dielectric bilayers: Influence of dopants and surfaces on the mechanical properties”, Phys. Rev. Materials4, 073603 (2020). https://doi.org/10.1103/PhysRevMaterials.4.073603
[6] Wing, B., “High-fidelity ptychographic imaging of highly periodic structures enabled by vortex high harmonic beams”, Optica 10, 1245-1252 (2023). https://doi.org/10.1364/OPTICA.498619
Required background: physics, optics, material science, nanoscience or related
Type of work: 10% literature study, 10% computation/modelling, 80% experimental
Supervisor: Claudia Fleischmann (KU Leuven)
Co-supervisor: Claudia Fleischmann (KU Leuven)
Daily advisor: Vitaly Krasnov
The reference code for this position is 2027-049. Mention this reference code in your application.