A versatile cryo-transfer system, connecting cryogenic focused ion beam sample preparation to atom probe microscopy

Area of Science:

• Materials Science
• Analytical Chemistry
• Nanotechnology

Background:

• Atom probe tomography (APT) provides 3D chemical and structural data.
• Standard APT workflows involve ambient condition sample transfers, risking degradation of sensitive materials.
• Environmental control during transfer is crucial for accurate analysis of air- or thermally-sensitive samples.

Purpose of the Study:

• To introduce a versatile transfer system for APT specimen handling.
• To enable controlled temperature and atmosphere transfers between preparation, FIB, and APT systems.
• To demonstrate the system's utility with an example of gallium-free grain boundary analysis in aluminum alloys.

Main Methods:

• Development and implementation of a versatile vacuum transfer system.
• Integration of the transfer system with a focused ion beam (FIB) system (Zeiss Crossbeam 540).
• Connection of the transfer system to a commercial atom probe system (CAMECA LEAP 4000X HR).

Main Results:

• The transfer system successfully maintained environmental control during specimen transfer.
• Cryogenic and room-temperature transfers were achieved in vacuum and atmospheric conditions.
• Atom probe data from gallium-free grain boundaries in an aluminum alloy, prepared using a gallium-based FIB, were successfully obtained.

Conclusions:

• The developed transfer system is effective for handling air- and thermally-sensitive samples for APT.
• This system prevents chemical or morphological changes, ensuring sample integrity.
• The technology facilitates advanced materials characterization by enabling analysis of previously challenging samples.