Practical Electron Microscopy and Database

An Online Book, Second Edition by Dr. Yougui Liao (2006)

Practical Electron Microscopy and Database - An Online Book

Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix

Distribution of Secondary Electrons

In bulk materials, SEs are emitted in the backward direction as shown in Figure 4819, while SEs are emitted in both backward and forward directions. One of the reasons why the SEM detectors are inserted above the sample stage is because SEM systems are mostly used for observing bulk materials.

Forward and backward secondary electrons

Figure 4819. Secondary electron emission: (a) backward-SEs, (b) forward-SEs