SEM Basics: Imaging Parameters

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Description

This lecture covers the basics of scanning electron microscopy (SEM), focusing on imaging parameters such as exposure time optimization, resolution, contrast, illumination, and detector choice. It explains how SEM images are generated step by step through sequential scanning of the sample, controlled by scan coils. The lecture also discusses the impact of accelerating voltage on penetration depth and signal, the generation of different types of signals (SE, BSE, X-rays), and the challenges faced in SEM imaging, including beam damage, charging effects, and strategies to mitigate them.

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Ion source

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