Postdoc position “Spectral filters for time-resolved and calibrated spectroscopy of EUV light sources”

Research / Academic

Are you enthusiastic about exploring scientific challenges with an industrial application perspective?

Extreme ultraviolet lithography (EUVL) is the latest generation of the semiconductor manufacturing technology powered by laser-produced-plasma light sources. These EUV light sources emit in a broad range of wavelengths spanning from soft x-rays to visible. A quantitative spectral characterization capability of such a broad wavelength range recently become available using a proprietary transmission grating spectrometer developed by XUV optics group ( The calibration of the charge-coupled-device (CCD) that are used as detectors in such a spectrometer is sensitive to the operation conditions of the light source. Cross-calibration of the CCD with other type of detectors such as photodiodes and investigating the light sources with time resolution provides wealth of information that is otherwise not accessible.

We are looking for a motivated and skilled post-doctoral researcher to carry out research on the fundamental physics questions on the calibration sensitivity and time-dependent spectral evolution of the EUV light source. Methods to enable inline calibration and time-resolved operation is to be developed in the project with the support of technical staff. Specifically, aim is to design multilayer spectral filters based on Bragg’s condition and deposition these designs using magnetron sputtering to enable cross-calibration of the CCD response and the photodiode response.

The XUV Optics Group at Twente has started a new multidisciplinary research program on these topics. We develop forefront fundamental research, relevant to high tech applications ( The research will take place in a state-of-the-art thin film laboratory within the MESA+ Institute for Nanotechnology at the University of Twente, in collaboration with various academic and industrial partners. The XUV group has a track record in developing thin film physics and holds several records in functional film properties, including the reflectivity of thin film multilayer optics.


Your goal is to develop the fundamental physics understanding on time-resolved and calibrated spectroscopy of EUV light sources. This includes:

  • Understanding the sensitivity of detector calibration to the operation conditions of the EUV light source,
  • Designing and developing multilayer spectral filters/coatings to enable online calibration at various wavelengths,
  • Analyzing the properties of the developed filters/coatings using characterization techniques such as AFM, XRD, XRR and SEM,
  • Understanding the time-dependent evolution of the spectral emission of the EUV light sources.


Your profile:

  • You have a doctoral degree in physics, materials science, optics, laser physics, solid state or surface physics or a related field.
  • It is a plus to have lab experience with vacuum systems, plasma, spectroscopy, thin film deposition and/or analysis setups.
  • You are an excellent team player in an enthusiastic group of scientists and engineers working on a common theme.
  • You are creative, like to push boundaries, and are highly motivated to address a major science challenge in thin film physics.
  • You are fluent in English and able to collaborate intensively with industrial and academic parties in regular meetings and work visits.

Salary Benefits:

  • You will be appointed on a fulltime position for 2 years.
  • The position is available immediately.
  • The university offers a dynamic ecosystem with enthusiastic colleagues in a stimulating scientific environment.
  • The post-doc salary is between € 3.877,- and € 5.090,- gross per month depending on experience and qualifications.
  • The offer further involves: a holiday allowance of 8% of the gross annual salary and a year-end bonus of 8.3%.
  • A solid pension scheme.
  • A minimum of 29-day holidays.
  • Numerous professional and personal development programs.
Work Hours:

38 hours per week


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