Low damage lamella preparation of metallic materials by FIB processing with low acceleration voltage and a low incident angle Ar ion milling finish

Abstract

SummaryMetallic materials are known to be very sensitive to Gallium (Ga) focused ion beam (FIB) processing. Crystal defects formed by FIB irradiation degrade the transmission electron microscope image quality, and it is difficult to distinguish original defects from FIB process‐induced damage. A solution to this problem is the low acceleration voltage and low incident angle (LVLA) Argon ion milling, which can be incorporated as an extensional countermeasure for FIB damage removal and eventually for preparation of high‐quality lamellae. The transmission electron microscope image quality of iron single crystal could be improved by removing crystal defects using the low acceleration voltage and low incident angle Argon ion milling finish. Lamella quality of the processing result was almost similar with that of the conventional electrolytic polishing.As a practical application of the process, low damage lamella of stainless cast steel could be prepared. Effectiveness of the FIB system equipped with the low acceleration voltage and low incident angle Argon ion milling function as a tool to make high‐quality metallic material lamellae is illustrated.

Charged Particle-Induced Surface Reactions of Organometallic Complexes as a Guide to Precursor Design for Electron- and Ion-Induced Deposition of Nanostructures

“…6−9 FEBID using ruthenium precursors has also been suggested for use in fabricating and repairing the capping layer of photomasks for extreme ultraviolet lithography (EUVL) 10,11 This deposition technique is also applied in academic research such as fabricating tips for local probe microscopes 12,13 and producing nanophotonic and nanoplasmonic structures. 14−16 FIBID has been used industrially in the repair of photomasks for both standard lithography (the Aerial Image Measurement System (AIMS) for 193 nm lithography) 9 and EUVL 17 and in TEM lamella preparation 18 and circuit editing. 19 FEBID is typically conducted in electron microscopes, with a background pressure of 1 × 10 −7 to 1 × 10 −5 Torr during delivery of a constant flux of volatile precursors.…”

“…Focused electron beam-induced deposition (FEBID) (Figure ) and focused ion beam-induced deposition (FIBID) are powerful nanofabrication techniques that utilize charged particles to drive deposition of spatially and geometrically well-defined 3D nanostructures from precursor compounds. − FEBID and FIBID are direct-write lithographic processes that can generate metal-containing nanostructures with precise control on planar and nonplanar surfaces without the need for masks or resists. As a result, FEBID has been used for industrial applications such as circuit editing and photomask repair. − FEBID using ruthenium precursors has also been suggested for use in fabricating and repairing the capping layer of photomasks for extreme ultraviolet lithography (EUVL) , This deposition technique is also applied in academic research such as fabricating tips for local probe microscopes , and producing nanophotonic and nanoplasmonic structures. − FIBID has been used industrially in the repair of photomasks for both standard lithography (the Aerial Image Measurement System (AIMS) for 193 nm lithography) and EUVL and in TEM lamella preparation and circuit editing …”

Revealing nano-scale lattice distortions in implanted material with 3D Bragg ptychography

“…FIB imaging and machining are known to cause dramatic material changes such as introduction of lattice defects 47 , large lattice strains 48 , amorphization 49 , and formation of Ga intermetallics 50 . In electron microscopy, FIB damage is often indistinguishable from the intrinsic defects and damage features of interest in the sample 51 , 52 . In the present case, it is worth noting that FIB-induced damage remains after employing preventative and mitigating measures, routinely employed in fabricating strain microscopy samples for electron microscopy including sacrificial capping, glancing incidence ion milling and the removal of surface material via low energy polishing (see Methods for fabrication details).…”

Removal of hydrocarbon contamination and oxide films from atom probe specimens

“…Five minutes of cleaning are sufficient to completely remove the detrimental layer from the surface for all specimens present on the grid at once. According to SRIM simulations (Ziegler, Ziegler, & Biersack, 2010) the exposure of Fe to 2 kV Ar ions results in a beam‐damaged layer of about 3 nm thickness (Sato et al, 2020) which is acceptable also for high resolution TEM investigations. For the investigation of materials which are more sensitive to beam damage than steels, such as semiconductors, the Ar ion beam acceleration voltage can be further reduced.…”