A Compact Light Source for Metrology Applications in the Euv Range

Simple SummaryContent extracted from patent full text and abstract with AI.

This invention discloses a compact and cost-effective light source for metrology applications, specifically in the Extreme Ultraviolet (EUV) wavelength range (5 to 30 nm). Based on synchrotron technology, the system integrates a linear electron accelerator, a booster ring, and a storage ring with a low-gap undulator to achieve highly stable, high-brightness, and tunable EUV light output. The design is optimized to fit within ordinary laboratory spaces, requires minimal maintenance, and delivers the power and beam stability necessary for advanced measurement (metrology) tasks.

Use CasesContent extracted from patent full text and abstract with AI.

• Actinic inspection and review of EUV lithography masks for defect detection in semiconductor manufacturing.
• On-wafer metrology of nanostructures, including measuring critical dimensions, line-edge roughness, height, and material composition.
• Coherent diffraction imaging (CDI) for high-resolution structural analysis of materials and devices in the nano-scale range.
• Quality control in the production of multilayer reflective optics and coatings for EUV applications.
• Development and testing of advanced semiconductor fabrication processes, including Directed Self-Assembly (DSA) and next-generation device architectures like FinFETs.
• Fundamental research in materials science, nanotechnology, and photon science requiring highly stable EUV sources.

BenefitsContent extracted from patent full text and abstract with AI.

• Highly compact system suitable for installation in conventional labs, minimizing infrastructure requirements.
• Delivers extremely stable, high-brightness EUV light matching the performance needs for advanced metrology.
• Cost-effective solution with low maintenance and ownership costs compared to large-scale synchrotrons or plasma-based EUV sources.
• Optimized for stability and power, making it compatible with sensitive techniques like coherent diffraction imaging.
• Top-up injection mechanism ensures constant beam intensity, improving measurement reproducibility and tool reliability.
• Provides a much-needed solution to the 'metrology gap' in advanced semiconductor and nanofabrication industries.

Technical Classifications (CPCs)

Inventors & Applicants

Patent Abstract

It is the objective of the present invention to provide a compact and cost effective light source based on a storage ring that can deliver sufficient power, stability and brightness for metrology methods in the EUV range. This objective is achieved according to the present invention by a compact light source (LS) based on synchrotron technology, comprising: a) a linear accelerator (LA) for electrons; b) a booster ring (BR) designed for top-up injection receiving the accelerated electrons via an injection pathway (SI); c) a storage ring (SR) receiving the accelerated electrons from the booster ring (BR) via top-up injection, keeping in this way the beam intensity stable to less than 5x10 -3 , wherein the electron energy of the electron beam in the storage ring (SR) ranges from 200 to 500 MeV and the current of the electron beam ranges from any lower value to 200 mA; and d) a low gap undulator (UN) comprised in the storage ring (SR); said undulator (UN) having an undulator period of 8 to 24 mm and a length of a large multiple of the undulator period. These measures result in a sufficiently compact source that fits into conventional labs or their maintenance areas and has quite low maintenance requirements and low cost of ownership. The wavelength of the light emitted by the undulator ranges from 5 to 30 nm. The light beam has an extreme stability smaller than 5.10 -3 , a sufficient power in a range larger than 10 mW and a high brightness larger than 10 kW/mm2.str. The parameter space of electron beam energy, undulator period length, number of undulator periods has therefore been optimized to provide the required wavelength and photon flux for metrology.