Scanning Electron Microscopy (SEM) Overview

Flashcards covering key concepts and terminology related to Scanning Electron Microscopy (SEM) for study and review.

Scanning Electron Microscopy (SEM)

A technique that uses a focused beam of high-energy electrons to generate signals from the surface of solid specimens, providing information on morphology, chemical composition, and crystalline structure.

Secondary Electrons

Electrons emitted from the sample surface as a result of the interaction with the incident electron beam, primarily used for imaging and showing morphology.

Backscattered Electrons (BSE)

Electrons that are scattered back out of the sample and provide information on the composition and contrast within multiphase samples.

Energy Dispersive Spectroscopy (EDS)

A technique used in SEM for quantitative and qualitative element analysis by measuring characteristic X-rays emitted from the sample.

Electron Backscatter Diffraction (EBSD)

A technique that analyzes backscattered electrons to determine crystalline structure and orientation of materials.

Characteristic X-Rays

X-rays that are emitted when excited electrons in an atom return to lower energy states, revealing elemental information of the sample.

Non-Destructive Analysis

A characteristic of SEM where the sample undergoes minimal damage during analysis, allowing for repeated examination.

Conductive Coating

A layer applied to electrically insulating samples to prevent charge build-up during SEM imaging, common materials include carbon and gold.

Vacuum System

An essential component of SEM that maintains the low-pressure environment required for electron microscopy.

Spatial Resolution

The smallest distance between two points that can be distinguished in an image, typically 50 to 100 nm for SEM.

Low Vacuum Operation

A mode in which SEM can operate without extensive sample preparation by allowing the examination of samples that would otherwise outgas.

Sample Preparation

The process of preparing a sample for SEM analysis, which can vary from minimal requirements to elaborate methods depending on the sample.