Contamination control for semiconductor equipment

Thema:
Systems lifetime

TNO is a specialist in contamination control for extreme ultraviolet lithography (EUV). We develop modules, research equipment, and strategies for the contamination control of EUV lithography scanners and materials and have been a trusted partner of ASML and Carl Zeiss in this regard for 20 years.

Leader in contamination control

We are specialists in contamination control research. We develop instrumentation and strategies for applications with the most challenging requirements in the High Tech Industry, including EUV lithography. The goal is to mitigate both particulate and molecular contamination. We have advanced facilities for the inspection and analysis of contamination, cleaning equipment, and setups to research the effect of EUV light and plasma. Our ultra-clean equipment is also suitable for validation of EUV masks.

EBL2: Unique EUV exposure and analysis facility at TNO

The EBL2 is a unique and independent analysis facility which contributes to the improvement of chips manufacturing by expanding the lifetime of materials which are exposed to EUV. As EBL2’s name suggests, first there was the EBL(1), built in 2006. To keep improving the development of chips, the equipment needed to manufacture these chips has to become more advanced. With the introduction of Extreme Ultra Violet lithography, the need for EUV test facilities increased, so it was time for a second generation. With EBL2, research assignments can be done 100 times faster, reducing turn-around times from months to hours. Another advantage of testing with EBL2 is that the experiments can be done outside the semiconductor factory, which shortens the development time of materials and components. In doing so, costs, risks and time-to-market are strongly reduced.

Our contamination control infrastructure

TNO has expanded its research and development (R&D) infrastructure. This second EUV exposure setup including surface analysis equipment was put into operation in 2018. It is used for research into materials such as optics, reticles, and pellicles, in collaboration with various parties in the EUV lithography field, including materials suppliers, end users, and equipment developers.

Functionalities:

  • The system accepts a variety of sample sizes, including standard EUV reticles with or without pellicles.
  • EBL2 also has an XPS system that can analyse EUV masks and pellicles, including a functionality for the production of a ‘defect map’.
  • Automated sample handling accepts SEMI-standard dual pods and maintains NXE compatibility for particle contamination on the back end.
  • The system is suitable for exposure of samples to very high doses of EUV, and for returning the reticles for use in a wafer fab.
EBL2 specifications
Category Specification
Optical power

>1 W in 2% BW at 13.5 nm (‘IB’) (10 W in OoB ((10-20 nm )) at 3 kHz

Intensity >1 W/mm2 IB in focus at 3 kHz
Cross-sectional optical focus 1 - 30 mm diameter (adjustable power density)
Source frequency 1 Hz - 10 kHz (default 3 kHz)
Sample size Max. 152x152x20 mm (EUV mask + pellicle possible)
Dose control <20 % with source feedback turned off
Continuous exposure time >100 hours
In-vacuum analysis techniques Ellipsometry and XPS

Facility for exposure and analysis: EBL2

We have been researching the interaction between EUV and different materials since 2000. To facilitate the ASML power roadmap, a second facility was developed for EUV exposure and in-situ surface analysis, also known as EBL2. This system helps customers evaluate their materials and components for NXE-relevant EUV radiation and environmental factors so as to increase the service life and prevent contamination.

The EUV Beam Line 2

The main facility for EUV development is the EUV Beam Line 2 (EBL2). This integrated vacuum system consists of a vacuum chamber, in which to carry out the EUV exposures in a controlled environment, and an XPS for surface analysis. In this system, samples can be transported between the test environment and the XPS without disturbing the vacuum.

In the vacuum system of the EBL2, samples are exposed to EUV radiation for extended periods of time in a controlled, representative environment. An in-situ ellipsometer with imaging is available for real-time monitoring of exposure progress.