From Ga-FIB to Bi-FIB: In situ TOF-SIMS Imaging of Buried Interfaces

Abstract

Focused ion beam (FIB) is widely used in sample processing for failure analysis of intricate electronic devices. In general, a Ga ion beam is used for this purpose. Recently, the combination of time-of-flight secondary ion mass spectrometry (TOF-SIMS) and FIB, so called FIB-TOF, has gained attention for enabling three-dimensional imaging of materials with complex chemical distributions and/or structures. However, a challenge of Ga-FIB is its slow processing speed. To address this issue, Bi-FIB has been investigated. Bi, the heaviest non-radioactive element on the periodic table, has the potential not only to enhance the processing speed but also to minimize the influence of FIB residues on TOF-SIMS spectra. In this paper, we present a comparison between Ga-FIB and Bi-FIB, and demonstrate the results of Bi-FIB for cross-sectional observations of all-solid-state battery materials.