Site-specific plan-view (S)TEM sample preparation from thin films using a dual-beam FIB-SEM.

Area of Science:

• Materials Science
• Nanotechnology
• Electron Microscopy

Background:

• Transmission electron microscopy (TEM) requires samples from multiple non-collinear orientations for comprehensive atomic structure and property evaluation.
• Preparing plan-view TEM samples from thin films on substrates is challenging, limiting nanoscale device analysis.

Purpose of the Study:

• To present a novel method for preparing high-quality, site-specific, plan-view TEM samples from thin films grown on substrates.
• To demonstrate the method's applicability using perovskite oxide and metal oxide thin films.

Main Methods:

• Utilized a dual-beam focused ion beam scanning electron microscope (FIB-SEM) system for site-specific sample preparation.
• Prepared 20-80 nm thin films of BaSnO3 on SrTiO3 and IrO2 on TiO2 substrates using molecular beam epitaxy.
• Evaluated sample quality and atomic-resolution imaging capabilities using aberration-corrected scanning transmission electron microscopy (STEM).

Main Results:

• Successfully prepared high-quality, site-specific, plan-view TEM samples from various thin-film/substrate systems.
• Demonstrated the method's effectiveness for atomic-resolution imaging and analysis.
• Confirmed the applicability of the method for thin films ranging from 20-80 nm in thickness.

Conclusions:

• The developed FIB-SEM method overcomes challenges in plan-view TEM sample preparation for thin films on substrates.
• The technique is suitable for atomic-resolution imaging and analysis, advancing materials characterization.
• The method can be extended to other site-specific samples and wafer-based devices.