Scanning Electron Microscopy: Principles, Instrumentation, and Applications

Question 1

Identify the component that is NOT present in a scanning electron microscope (SEM).

Accepted Answer

Optical microscope

Answer

Electron gun

Answer

Condenser lenses

Answer

Objective lens

Question 2

What is the primary role of condenser lenses in an SEM?

Accepted Answer

Focusing the electron beam onto the sample

Answer

Accelerating the electrons

Answer

Controlling the brightness of the electron beam

Answer

Magnifying the image

Question 3

Compared to light microscopy, SEM offers a key advantage. Which one is it?

Accepted Answer

Higher resolution imaging

Answer

Ability to analyze non-transparent samples

Answer

Larger depth of field

Answer

Real-time imaging

Question 4

Which of the following fields does NOT commonly utilize SEM?

Accepted Answer

Astronomy

Answer

Materials science

Answer

Biology

Answer

Archaeology

Question 5

What is a limitation of using Scanning Electron Microscopy (SEM) for materials analysis?

Accepted Answer

Large sample size requirement

Answer

High-resolution imaging

Answer

Elemental composition analysis

Answer

Crystal structure analysis

Question 6

Which of the following is NOT an application of Scanning Electron Microscopy (SEM) in materials characterization?

Accepted Answer

Measurement of electrical properties

Answer

Surface morphology analysis

Answer

Elemental composition analysis

Answer

Crystal structure analysis

Question 7

Which component is not typically found in a Scanning Electron Microscope (SEM)?

Accepted Answer

Laser source

Answer

Electron gun

Answer

Condenser lens

Answer

Objective lens

Question 8

Which of the following is NOT a fundamental component of a Scanning Electron Microscope (SEM)?

Accepted Answer

Energy-Dispersive X-ray Spectrometer (EDS)

Answer

Electron gun

Answer

Objective lens

Answer

Vacuum chamber

Question 9

Which of the following is the core component of a Scanning Electron Microscope (SEM) that generates the electron beam?

Accepted Answer

Electron gun

Answer

Light source

Answer

Magnetic lens

Answer

Sample holder

Question 10

In an SEM, what type of lenses are primarily responsible for controlling and focusing the electron beam?

Accepted Answer

Magnetic lenses

Answer

Apertures

Answer

Electrostatic lenses

Answer

Condensers

Question 11

Which of the following detectors in SEM is specifically designed to provide information about the sample's surface topography?

Accepted Answer

Secondary electron detector

Answer

Energy dispersive X-ray spectrometer

Answer

Cathodoluminescence detector

Answer

Backscattered electron detector

Question 12

What is the primary factor that influences the resolution of an SEM image?

Accepted Answer

Beam diameter

Answer

Magnification

Answer

Sample size

Answer

Detection efficiency

Question 13

For SEM analysis of non-conducting materials, which sample preparation technique is commonly employed to prevent electrostatic charging?

Accepted Answer

Sputter coating

Answer

Thermal evaporation

Answer

Cryo-sectioning

Answer

Chemical etching

Question 14

In an SEM, the backscattered electron detector provides information primarily about the sample's:

Accepted Answer

Atomic number

Answer

Surface roughness

Answer

Crystal structure

Answer

Chemical composition

Question 15

Which of the following SEM imaging modes is used to generate three-dimensional representations of a sample's surface?

Accepted Answer

Stereomicroscopy

Answer

Secondary electron imaging

Answer

Energy dispersive X-ray spectroscopy

Answer

Backscattered electron imaging

Question 16

What is the primary function of the Energy Dispersive X-ray Spectrometer (EDS) in SEM?

Accepted Answer

Elemental analysis of the sample

Answer

Crystallographic analysis

Answer

Surface morphology analysis

Answer

Topography analysis

Question 17

In which field is SEM extensively used for characterizing materials?

Accepted Answer

Materials characterization

Answer

Medical imaging

Answer

Biological research

Answer

Forensic science

Question 18

Which of the following is NOT a fundamental principle of Scanning Electron Microscopy (SEM)?

Accepted Answer

Transmitted electron beam

Answer

Electron-sample interaction and secondary electron generation

Answer

Raster scanning of the electron beam

Answer

Detection and amplification of signals

Question 19

What is the primary role of the electron gun in an SEM?

Accepted Answer

Generate a focused electron beam

Answer

Amplify and display the image

Answer

Detect secondary electrons emitted from the sample

Answer

Create and maintain a vacuum environment

Question 20

Which detector type is primarily used to generate secondary electron images in SEM?

Accepted Answer

Everhart-Thornley detector

Answer

Energy-dispersive X-ray detector

Answer

Transmission detector

Answer

Backscattered electron detector

Question 21

What is the main purpose of the beam blanker in an SEM?

Accepted Answer

Prevent electron beam damage to the sample

Answer

Amplify the image signal for better visualization

Answer

Create a vacuum seal during sample loading

Answer

Focus the electron beam onto the sample surface

Question 22

What type of information can be obtained from analyzing the X-ray spectrum generated by an SEM?

Accepted Answer

Elemental composition of the sample

Answer

Surface roughness

Answer

Magnetic properties

Answer

Crystallographic structure

Question 23

Which material type is generally not suitable for SEM analysis?

Accepted Answer

Liquids

Answer

Metals

Answer

Polymers

Answer

Ceramics

Question 24

In a Scanning Electron Microscope (SEM), which component is responsible for the production of a concentrated electron beam?

Accepted Answer

Electron gun

Answer

Condenser lens

Answer

Detector

Answer

Sample stage

Question 25

What is the primary purpose of the condenser lenses in SEM?

Accepted Answer

Focusing the electron beam onto the sample surface

Answer

Detecting backscattered electrons

Answer

Accelerating the electrons

Answer

Creating an image of the sample

Question 26

Which of the following signals is primarily used in SEM to generate topographic images of the sample surface?

Accepted Answer

Secondary electrons

Answer

Cathodoluminescence

Answer

Backscattered electrons

Answer

X-rays

Question 27

Which of the following is NOT an application of SEM in the characterization of materials?

Accepted Answer

Determining the thermal conductivity of a material

Answer

Identifying crystal structures

Answer

Analyzing the surface morphology

Answer

Determining elemental compositions

Question 28

Which sample preparation technique is commonly used prior to SEM analysis?

Accepted Answer

Sputter coating with a conductive material

Answer

Cryogenic freezing only

Answer

Chemical etching only

Answer

Mechanical polishing only

Question 29

What is the primary function of the Energy Dispersive X-ray (EDX) detector in SEM?

Accepted Answer

Analyzing the elemental composition of the sample

Answer

Measuring the sample thickness

Answer

Creating 3D images of the sample

Answer

Detecting secondary electrons

Question 30

What is the typical range of accelerating voltage used in SEM?

Accepted Answer

1-30 kV

Answer

100-500 kV

Answer

1-10 kV

Answer

100-300 kV

Question 31

Which of the following is the primary function of the electron gun in a scanning electron microscope?

Accepted Answer

Generates a focused electron beam

Answer

Accelerates the electron beam

Answer

Detects the secondary electrons

Answer

Condenses the electron beam

Question 32

What is the role of the condenser coils in a SEM?

Accepted Answer

Focus the electron beam onto the sample

Answer

Generate the electron beam

Answer

Accelerate the electron beam

Answer

Detect the secondary electrons

Question 33

Which type of signal is primarily used for imaging in SEM?

Accepted Answer

Secondary electrons

Answer

Characteristic X-rays

Answer

Auger electrons

Answer

Backscattered electrons

Question 34

Which of the following is NOT an application of SEM in materials characterization?

Accepted Answer

Measuring electrical properties

Answer

Determining elemental composition

Answer

Investigating crystal structure

Answer

Analyzing surface morphology

Question 35

Which of the following techniques can be combined with SEM to provide elemental analysis?

Accepted Answer

Energy-dispersive X-ray spectroscopy (EDS)

Answer

Ultraviolet-visible spectroscopy (UV-Vis)

Answer

Atomic force microscopy (AFM)

Answer

Transmission electron microscopy (TEM)

Question 36

What is the fundamental difference between SEM and TEM?

Accepted Answer

SEM images the surface, while TEM images the interior of a sample

Answer

SEM uses a focused electron beam, while TEM uses a broad electron beam

Answer

SEM is a non-destructive technique, while TEM is a destructive technique

Question 37

Which of the following factors primarily affects the resolution in SEM?

Accepted Answer

Electron beam energy

Answer

Detector efficiency

Answer

Sample size

Answer

Scanning speed

Question 38

Which of the following is NOT a component of a Scanning Electron Microscope (SEM)?

Accepted Answer

Optical lens

Answer

Electron gun

Answer

Condenser lens

Answer

Detector

Question 39

What is the primary function of the electron gun in an SEM?

Accepted Answer

To emit a focused beam of electrons

Answer

To create a vacuum within the sample chamber

Answer

To detect secondary electrons

Answer

To magnify the sample

Question 40

Which of the following signals is primarily used to obtain surface morphology information in SEM?

Accepted Answer

Secondary electrons

Answer

Characteristic X-rays

Answer

Backscattered electrons

Answer

Transmitted electrons

Question 41

Which of the following sample preparation techniques is commonly used to enhance the electrical conductivity of non-conductive materials for SEM analysis?

Accepted Answer

Sputter coating

Answer

Annealing

Answer

Chemical etching

Answer

Thermal evaporation

Question 42

What is the primary factor that affects the resolution of an SEM image?

Accepted Answer

Electron beam spot size

Answer

Sample size

Answer

Vacuum level

Answer

Detector sensitivity

Question 43

What is the typical energy range of the electron beam used in SEM?

Accepted Answer

1-30 keV

Answer

1-10 MeV

Answer

100-300 keV

Answer

100-300 MeV