Lect06_notes

Three prominent types of electron guns w lament lab6

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%@%ABC== CBEMS 164 – XRD, SEM & Microanalysis: Lecture 06 ! 4 The Electron Gun! Three prominent types of electron guns! ! W filament! ! LaB6 filament! ! Field Emission Gun (FEG)! ! ! !  Each emits electrons in an electric field that brings the beam to a focus! ! The first cross-over! ! ! !  The first cross-over is then projected and demagnified to form the probe that is incident on the surface of the specimen! ! !  CBEMS 164 – XRD, SEM & Microanalysis: Lecture 06 ! 5 Self-Biased Thermionic Gun! !  Cross-over at D0 is demagnified and projected down the column to become the imaging probe! ! ! CBEMS 164 – XRD, SEM & Microanalysis: Lecture 06 ! 6 Self-Biased Thermionic Gun! !  Cross-over at D0 is demagnified and projected down the column to become the imaging probe! ! ! CBEMS 164 – XRD, SEM & Microanalysis: Lecture 06 ! 7 LaB6 Filaments! !  LaB6 – Crystal, ground to point, resistively heated! ! ! CBEMS 164 – XRD, SEM & Microanalys...
View Full Document

This note was uploaded on 01/16/2014 for the course CBEMS 164 taught by Professor Porter,j during the Fall '08 term at UC Irvine.

Ask a homework question - tutors are online