Large Area Real-Space Crystallography and Thickness Determination of Mesoscopic Semiconductor Membranes Using Zone Axis Patterns, Cold Field-Emission SEM/STEM, and Analytical S/TEM

Published

July 25, 2025

Author(s)

Vladimir Oleshko, Glenn Holland, Daron Westly, John Villarrubia

Abstract

Structural and dimensional characterization of layered structures in semiconductors is increasingly important for microelectronics manufacturing because of the continuing downward scaling of devices. Manufacturers require high-precision non-destructive metrology to determine local crystal symmetry, orientation, defects, and layer thickness with high spatial resolution over large areas. Scanning and transmission electron microscopy (S/TEM) are widely employed to ensure that the structural uniformity and device dimensions enable the desired functionality and performance. Electron diffraction (ED) techniques in S/TEMs with an incident beam oriented along a lattice direction parallel to a high-symmetry major zone axis are often used to characterize the crystal symmetry, orientation, defects, and thickness of silicon on insulators and related layered semiconductor structures. When layer thickness increases above 100 nm, interference of dynamically diffracted beams may result in the formation of real-space zone axis patterns (ZAPs) that exhibit complex symmetric intensity distributions like those observed with convergent-beam ED (CBED) patterns. ZAPs, therefore, allow direct crystallographic analysis of the examined area. ZAPs are usually observed in images of foils symmetrically bent near the zone axis. Here, we report on the use of ZAPs arising from the varying angle between incident electrons within the converging beam and the flat specimen for nondestructive characterization of crystallographic uniformity and thickness of suspended mesoscopic single crystal c-Si membranes supplied by Norcada, Inc.

Proceedings Title

Microscopy & Microanalysis 2025, Proceedings of the MSA/MAS Annual Meeting, July 27-31, 2025, Salt Lake City, Utah

Volume

31

Issue

7

Conference Dates

July 27-31, 2025

Conference Location

Slat Lake City, UT, US

Conference Title

Microscopy & Microanalysis 2025

Pub Type

Conferences

Download Paper

https://doi.org/10.1093/mam/ozaf048.272

Local Download

Keywords

Semiconductors, layered structures, high-precision non-destructive metrology, SEM, S/TEM, ZAP, LACBED, EELS

Citation

Oleshko, V. , Holland, G. , Westly, D. and Villarrubia, J. (2025), Large Area Real-Space Crystallography and Thickness Determination of Mesoscopic Semiconductor Membranes Using Zone Axis Patterns, Cold Field-Emission SEM/STEM, and Analytical S/TEM, Microscopy & Microanalysis 2025, Proceedings of the MSA/MAS Annual Meeting, July 27-31, 2025, Salt Lake City, Utah, Slat Lake City, UT, US, [online], https://doi.org/10.1093/mam/ozaf048.272, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=959536 (Accessed October 9, 2025)