A5070559712- Laser-induced spectroscopy and plasma
- Atomic and Molecular Physics
- Laser-Matter Interactions and Applications
- Plasma Diagnostics and Applications
- Ion-surface interactions and analysis
- Diamond and Carbon-based Materials Research
- Laser Design and Applications
- Laser Material Processing Techniques
- Mass Spectrometry Techniques and Applications
- Metal and Thin Film Mechanics
- Laser-Ablation Synthesis of Nanoparticles
- Electron and X-Ray Spectroscopy Techniques
- Analytical chemistry methods development
- Advancements in Photolithography Techniques
- Copper Interconnects and Reliability
- X-ray Spectroscopy and Fluorescence Analysis
- Quantum optics and atomic interactions
- Electrohydrodynamics and Fluid Dynamics
- Analytical Chemistry and Sensors
- Laser-Plasma Interactions and Diagnostics
Vrije Universiteit Amsterdam
2016-2022
Advanced Research Center for Nanolithography (Netherlands)
2016-2022
Institute of Spectroscopy
2017
Abstract Extreme ultraviolet (EUV) lithography is currently entering high-volume manufacturing to enable the continued miniaturization of semiconductor devices. The required EUV light, at 13.5 nm wavelength, produced in a hot and dense laser-driven tin plasma. atomic origins this light are demonstrably poorly understood. Here we calculate detailed opacity spectra using Los Alamos physics suite ATOMIC validate these calculations with experimental comparisons. Our key finding that largely...
Shining a short, intense laser pulse on micrometer-sized droplets of liquid metal creates plasma that is bright source extreme ultraviolet (EUV) light. The authors study in detail the propulsion and deformation such due to ``kick'', unveil underlying mechanisms scaling laws. Optimizing EUV sources for next-generation nanolithography requires deep understanding both droplet-laser coupling droplet fluid-dynamical response, which this work provides.
Plasmas produced from microdroplets of liquid tin provide light at an extreme ultraviolet (EUV) wavelength 13.5 nm, for state-of-the-art nanolithography that will enable the continuation Moore's law in shrinking transistors. Currently CO${}_{2}$ gas lasers are used to drive such plasma; transitioning modern solid-state would have significant advantages, if efficiency converting laser energy into 13.5-nm radiation were sufficiently competitive. This study quantifies solid-state-laser-driven...
We experimentally re-evaluate the fine structure of Sn$^{11+...14+}$ ions. These ions are essential in bright extreme-ultraviolet (EUV) plasma-light sources for next-generation nanolithography, but their complex electronic is an open challenge both theory and experiment. combine optical spectroscopy magnetic dipole $M1$ transitions, a wavelength range covering 260\,nm to 780\,nm, with charge-state selective ionization electron beam ion trap. Our measurements confirm predictive power \emph{ab...
We analyze the complex level structure of ions with many-valence-electron open-[Kr] $4{d}^{m}$ subshells ($m=7--4$) ab initio calculations based on configuration-interaction many-body perturbation theory (CI+MBPT). Charge-state-resolved optical and extreme ultraviolet (EUV) spectra ${\mathrm{Sn}}^{7+}--{\mathrm{Sn}}^{10+}$ were obtained using an electron beam ion trap. Semiempirical spectral fits carried out orthogonal parameters technique cowan code lead to 90 identifications...
The measurement of the propulsion metallic microdroplets exposed to nanosecond laser pulses provides an elegant method for probing ablation pressure in a dense laser-produced plasma. We present measurements velocity over three decades driving Nd:YAG pulse energy and observe near-perfect power law dependence. Simulations performed with RALEF-2D radiation-hydrodynamic code are shown be good agreement above specific threshold energy. simulations highlight importance radiative losses which...
Experimental scaling relations of the optical depth are presented for emission spectra a tin-droplet-based, 1-μm-laser-produced plasma source extreme-ultraviolet (EUV) light. The observed changes in complex spectral over wide range droplet diameters (16–65 μm) and laser pulse durations (5–25 ns) accurately captured relation featuring as single, pertinent parameter. scans were performed at constant intensity 1.4 × 1011 W/cm2, which maximizes 2% bandwidth around 13.5 nm relative to total...
Extreme-ultraviolet (EUV) spectra of ${\mathrm{Sn}}^{13+}\ensuremath{-}{\mathrm{Sn}}^{15+}$ ions have been measured in an electron-beam ion trap (EBIT). A matrix inversion method is employed to unravel convoluted from a mixture charge states typically present EBIT. The benchmarked against the spectral features resonance transitions ${\mathrm{Sn}}^{13+}$ and ${\mathrm{Sn}}^{14+}$ ions. Three new EUV lines confirm its previously established level structure. This relevant for nanolithography...
Abstract The emission spectra from an industrial, droplet-based, laser-produced plasma, extreme ultraviolet light source for nanolithography are here presented and analyzed. dependence of spectral features on the CO 2 -drive-laser intensity is studied by changing beam spot size at constant pulse energy duration. We characterize spectrum fitting results atomic structure calculations to short-wavelength region (7–11 nm), where contributions various charge states can be resolved, obtain...
We present the results of calibration a channeltron-based electrostatic analyzer operating in time-of-flight mode (ESA-ToF) using tin ions resulting from laser-produced plasma, over wide range charge states and energies. Specifically, channeltron electron multiplier detection efficiency spectrometer resolution are calibrated, count rate effects characterized. With obtained overall response function, ESA-ToF is shown to accurately reproduce charge-integrated measurements separately...
We present the results of spectroscopic measurements in extreme ultraviolet regime (7–17 nm) molten tin microdroplets illuminated by a high-intensity 3 J, 60 ns Nd:YAG laser pulse. The strong 13.5 nm emission from this laser-produced plasma (LPP) is relevance for next-generation nanolithography machines. Here, we focus on shorter wavelength features between 7 and 12 which have so far remained poorly investigated despite their diagnostic relevance. Using flexible atomic code calculations...
The cavitation-driven expansion dynamics of liquid tin microdroplets is investigated, set in motion by the ablative impact a 15-ps laser pulse. We combine high-resolution stroboscopic shadowgraphy with an intuitive fluid dynamic model that includes onset fragmentation, and find good agreement between experimental data for two different droplet sizes over wide range pulse energies. dependence initial velocity on these parameters heuristically captured single power law. Further, obtained...
Laser-produced Sn plasma sources are used to generate extreme ultraviolet (EUV) light in state-of-the-art nanolithography. An and optical spectrum is measured from a droplet-based laser-produced plasma, with spectrograph covering the range 200 - 800 nm. This contains hundreds of spectral lines lowly charged tin ions Sn$^{1+}$ Sn$^{4+}$ which major fraction was hitherto unidentified. We present identify selected class belonging quasi-one-electron, Ag-like ([Kr]$4d^{10} nl$ electronic...
We present and experimentally validate a model describing the sensitivity of tilt angle, expansion, propulsion velocity tin micro-droplet irradiated by 1 μm Nd:YAG laser pulse to its relative alignment. This is particularly relevant in industrial plasma sources extreme ultraviolet light for nanolithographic applications. Our has but single parameter: dimensionless ratio spot size effective droplet, which related position critical density surface. enables development straightforward scaling...
Laser-produced tin plasmas are the prime candidates for generation of extreme ultraviolet (EUV) light around 13.5 nm in nanolithographic applications.This is generated primarily by atomic transitions highly charged ions: Sn 8+ -Sn 14+ .Due to electronic configurations these charge states, thousands lines emit nm, clustered a so-called unresolved transition array.As result, accurate line identification becomes difficult this regime.Nevertheless, issue can be circumvented if one turns optical:...
Laser-induced cavitation in tin microdroplets can be used to obtain optimized laser targets EUV sources for nanolithography. We present our experimental analysis of microdroplet expansion and find good agreement with a fluid dynamics model.
Laser-produced tin plasmas are used for the generation of extreme ultraviolet light nanolithography. We use an extensive diagnostic toolset to characterize and understand physics these plasma sources at atomic level.
Synopsis Highly charged tin ions are the sources of extreme ultraviolet (EUV) light at 13.5-nm wavelength in laser-produced transient plasmas for next-generation nanolithography. Generating this EUV required power, reliability, and stability however presents a formidable task that combines industrial innovations with challenging scientific questions. We will present work on spectroscopy out YAG-laser-driven plasma surprising answer to key question: what makes light?