Scanning Electron Microscopy: A Comprehensive Guide for Beginners

Question 1

Which component is NOT essential in the primary setup of a scanning electron microscope (SEM)?

Accepted Answer

Fluorescence detector

Answer

Electron source

Answer

Condenser and objective lenses

Answer

Vacuum chamber

Question 2

Which type of signal provides detailed information about the sample's surface topography in SEM?

Accepted Answer

Secondary electrons

Answer

Backscattered electrons

Answer

X-rays

Answer

Electron beam

Question 3

What is the principle behind energy-dispersive X-ray spectroscopy (EDS) in SEM?

Accepted Answer

Detection of characteristic X-rays emitted by excited atoms in the sample

Answer

Measurement of the energy of secondary electrons

Answer

Analysis of the magnetic properties of the sample

Answer

Imaging of the sample surface at high resolution

Question 4

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

Accepted Answer

5-15 keV

Answer

0.5-1 keV

Answer

20-30 keV

Answer

50-100 keV

Question 5

What is the primary application of SEM in materials failure analysis?

Accepted Answer

Identifying the root cause of material failures and defects

Answer

Characterizing the microstructure of materials

Answer

Measuring the thickness of thin films

Answer

Determining the composition of alloys

Question 6

Which advantage does SEM offer over transmission electron microscopy (TEM)?

Accepted Answer

Larger depth of field, allowing for imaging of rough or uneven surfaces.

Answer

Higher magnification, providing finer details

Answer

Ability to analyze non-conductive samples without special preparation

Answer

Lower cost and wider accessibility

Question 7

The typical range of accelerating voltage used in SEM is:

Accepted Answer

20-50 kV

Answer

1-5 kV

Answer

5-20 kV

Answer

50-100 kV

Question 8

Which detector type is commonly employed for image acquisition in SEM?

Accepted Answer

Electron multiplier detector

Answer

X-ray detector

Answer

Energy-dispersive X-ray (EDX) detector

Answer

Transmission electron microscopy (TEM) detector

Question 9

For non-conductive materials, which sample preparation technique is suitable for SEM analysis?

Accepted Answer

Carbon coating

Answer

Mechanical polishing

Answer

Chemical etching

Answer

Ion milling

Question 10

The primary advantage of using Energy-Dispersive X-ray (EDX) in SEM is:

Accepted Answer

Obtaining elemental composition information

Answer

Enhancing image resolution

Answer

Reducing sample preparation time

Answer

Increasing image brightness

Question 11

SEM finds applications in a wide range of fields. Which of the following is NOT a typical application of SEM?

Accepted Answer

Electromagnetic field mapping

Answer

Surface topography analysis

Answer

Failure analysis

Answer

Particle characterization

Question 12

Compared to light microscopy, SEM generally offers:

Accepted Answer

Higher resolution

Answer

Similar resolution

Answer

Lower resolution

Answer

Dependent on the wavelength of light

Question 13

In SEM, which software component is responsible for controlling image acquisition and processing?

Accepted Answer

Image acquisition software

Answer

Objective lens

Answer

Detector

Answer

Vacuum system

Question 14

What is the analytical technique used in SEM for elemental analysis?

Accepted Answer

Energy-dispersive X-ray spectroscopy (EDX)

Answer

Wavelength-dispersive X-ray spectroscopy (WDX)

Answer

Auger electron spectroscopy (AES)

Answer

X-ray photoelectron spectroscopy (XPS)

Question 15

In backscattered electron imaging (BEI), what material characteristic primarily determines the contrast in the image?

Accepted Answer

Atomic number

Answer

Sample density

Answer

Surface roughness

Answer

Beam energy

Question 16

In Scanning Electron Microscopy (SEM), what is the primary purpose of the electron gun?

Accepted Answer

To generate a focused beam of electrons

Answer

To control the magnification and resolution of the image

Answer

To create and maintain a high vacuum environment

Answer

To detect and amplify signals from the sample

Question 17

What is the main function of the condenser lens in SEM?

Accepted Answer

To focus and converge the electron beam onto the sample surface

Answer

To scatter or deflect the electron beam

Answer

To detect and collect secondary electrons

Answer

To magnify the resulting image

Question 18

In SEM, the generation of secondary electrons primarily results from:

Accepted Answer

Inelastic collisions between the primary electron beam and sample atoms

Answer

Elastic collisions between the primary electron beam and sample atoms

Answer

Ionization of sample atoms by the primary electron beam

Question 19

Which detector in SEM is utilized for elemental analysis?

Accepted Answer

Energy dispersive X-ray spectrometer (EDS)

Answer

Electron multiplier

Answer

Channeltron detector

Question 20

What is a key advantage of using backscattered electrons in SEM imaging?

Accepted Answer

Enhanced contrast based on the atomic number of the sample

Answer

Reduced sample charging effects

Answer

Higher resolution imaging

Answer

Increased depth of field

Question 21

What is the main purpose of using a sputter coater in SEM sample preparation?

Accepted Answer

To deposit a thin conductive layer on non-conductive samples

Answer

To remove surface contaminants

Answer

To enhance surface roughness

Question 22

Which application of SEM involves examining the surfaces of fractured materials?

Accepted Answer

Failure analysis

Answer

Biological imaging

Answer

Materials characterization

Answer

Microelectronics fabrication