A simple vacuum suitcase for enabling plasma facing component characterization in fusion devices

Area of Science:

• Fusion energy research
• Materials science
• Surface analysis

Background:

• Tokamak plasma-facing components (PFCs) require precise surface characterization.
• Existing methods for PFC analysis are often limited by tokamak design constraints and potential contamination.

Purpose of the Study:

• To introduce a vacuum suitcase, the Sample Exposure Probe (SEP), for transporting tokamak samples.
• To enable high-resolution surface analysis of PFCs in a dedicated, controlled environment.

Main Methods:

• Development of the Sample Exposure Probe (SEP) with mobile ultra-high vacuum pumping.
• Integration of active pumping for sample transfer between the Lithium Tokamak eXperiment-β (LTX-β) and X-ray Photoelectron Spectroscopy (XPS).
• Inclusion of a thermocouple and button heater to monitor and match plasma-exposed sample temperatures.

Main Results:

• The SEP successfully enabled vacuum transfer of samples from LTX-β to an XPS system.
• Improved vacuum conditions during transfer and analysis led to reduced sample contamination.
• Higher resolution and signal-to-noise ratio in XPS scans facilitated accurate peak identification.

Conclusions:

• The SEP offers a viable alternative for characterizing PFCs, overcoming limitations of in-situ tokamak diagnostics.
• This vacuum suitcase technology enhances the accuracy and detail of surface analysis for fusion applications.
• The SEP represents the first vacuum suitcase for fusion with integrated active pumping, with potential for broader application in other fusion devices.