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INSTRUMENTAL SEMINAR
SEM - SCANNING ELECTRON MICROSCOPE
Dr. Madduru Muni Haritha
1st year M.D Scholar
Department of Rasashastra and Bhaishajya Kalpana
KLE SHRI B.M.K Ayurveda Mahavidyalaya, Belagavi
2/18/2024 Scanning electron microscope 1
CONTENTS
• History
• Introduction
• Electron microscopy
• Signals produced by SEM
• Working principal
• Magnification
• Sample preparation
• Application
• Advantages
• Disadvantages
• Research articles
• Conclusion
• Own view
2/18/2024 Scanning electron microscope 2
HISTORY
• A German scientist ‘Max Knoll’ built the first scanning microscope in 1935.
• In 1937 ‘Manfred von Ardenne’ invented a microscope
with high resolution.
• SEM was further developed by Prof. Charles Oatley and his
student Gary steward in 1965 at Cambridge instrument
company as “Stereoscan”
2/18/2024
Scanning electron microscope
3
INTRODUCTION
• The scanning electron microscope is a type of
electron microscope that images the sample
surface by scanning it with a high - energy beam
of electrons in a raster scan pattern.
(Rectangular pattern of image capture and
reconstruction of it in a monitor).
• The electrons interact with the atoms that make
up the sample producing signals that contain
information about the samples surface
topography, composition and other properties
such as electrical conductivity
2/18/2024 Scanning electron microscope 4
ELECTRON MICROSCOPY
• An electron microscope is a type of
microscope that uses a particle beam of
electrons to illuminate a specimen and creates
a high magnified image.
• Electron microscope have a much greater
resolving power than light microscopes that
uses electromagnetic radiation and can obtain
much “higher magnifications upto 2 million
times, while the best light microscopes are
limited to magnifications to 2000 times”
2/18/2024 Scanning electron microscope 5
SIGNALS PRODUCED BY SEM
• Secondary electrons
• Back – scattered electrons
• Characteristic x rays
• Light (cathodoluminescence)
• Specimen current and transmitted electrons
2/18/2024 Scanning electron microscope 6
Secondary electron detector
• Secondary electron detectors are common in all
SEM’s but it is rare that a single machine would have
detectors for all possible signals.
• The signals here results from interactions of the
electron beam with atoms at or near the surface of the
sample.
2/18/2024 Scanning electron microscope 7
2/18/2024 Scanning electron microscope 8
SEM WORKING PRINCIPAL
Electron - Solid Interactions
 When an electron beam strikes a sample, large number of signals are generated.
2/18/2024 Scanning electron microscope 9
Contd….
• In most common and standard detection mode, secondary electron
imaging or SEI, the SEM can produce very high resolution images of a
surface, revealing details about less than 1 to 5 nm in size.
• Due to very narrow electron
beam, SEM micrographs have
a large depth of field yielding a
characteristic 3D appearance
useful for understanding the
surface structure of a sample.
2/18/2024 Scanning electron microscope 10
2/18/2024 Scanning electron microscope 11
Scanning process and image formation
• In a typical SEM, an electron beam is thermionically emitted
from an electron gun fitted with a tungsten filament cathode.
Why only tungsten is used ?
• Tungsten is normally used in thermionic electron guns
because it has the highest melting point and lowest vapour
pressure of all metals, thereby allowing it to be heated for
electron emission, and because of its low cost.
2/18/2024 Scanning electron microscope 12
Electron Gun
2/18/2024 Scanning electron microscope 13
Contd…
• The electron beam generated, which typically has an energy ranging from a
few hundred eV to 40k eV is focoused by one or two condenser lenses to a
spot about 0.4nm to 5nm in diameter.
• The beam passes through pairs of scanning coils or pairs of deflector plates
in the electron column, typically in the final lens, which deflect the beam in
the x and y axis so that it scans in a raster fashion over a rectangular area of
the sample surface.
• Electronic amplifiers of various types are used to amplify the signals which
are displayed as variations in brightness on a cathode ray tube(CRT).
2/18/2024 Scanning electron microscope 14
MAGNIFICATION
• The electron gun can generate a beam with sufficiently small diameter,
SEM in principal, work entirely without condenser or objective lenses,
although it might not be very versatile or achieve very high resolution.
• The image may be captured by photography from a high resolution
cathode ray tube, but in modern machines is digitally captured and
displayed on a computer monitor and saved to a computer hard disc.
• Magnification in a SEM can be controlled over a range of upto 6
orders of magnitude from about 10 to 5000,000 times.
2/18/2024 Scanning electron microscope 15
Contd…
• Unlike optical and transmission electron microscopes, image
magnification in the SEM is not a function of the power of objective
lens.
• SEM may have condenser and objective lenses, but their function is to
focus the beam to a spot, and not to image the specimen.
• Assuming that the display screen has a fixed size, higher magnification
results from reducing the size of the raster on specimen, and vice
versa.
2/18/2024 Scanning electron microscope 16
INSTRUMENTATION
1. A column which generates a beam of
electrons.
2. A specimen chamber where the
electron beam interacts with the sample.
3. Detectors to monitor the different
signals that result from the electron beam
/sample interaction.
4. Monitor - A viewing system that
builds an image from the detector signal.
2/18/2024 Scanning electron microscope 17
A LOOK INSIDE THE COLUMN
2/18/2024 Scanning electron microscope 18
Electron detection and sample stage
Sample stage
2/18/2024 Scanning electron microscope 19
• SEM is an incredible tool for seeing the unseen worlds of microspace.
• SEM creates the magnified images by using electrons instead of light waves.
2/18/2024 Scanning electron microscope 20
• An electron gun at the top emits a beam of high energy electrons. This beam
travels downwards through a series of magnetic lenses designed to focus the
electrons to a very fine spot.
2/18/2024 Scanning electron microscope 21
• Near the bottom, a set of scanning coils move the focused beam back and
forth across the specimen row by row.
2/18/2024 Scanning electron microscope 22
• As the electron beam hits each spot on the sample, secondary electrons
are knocked loose from its surface. A detector counts these electrons and
sends signals to an amplifier.
2/18/2024 Scanning electron microscope 23
• The final image is built up from the number of electrons emitted from
each spot on the sample.
2/18/2024 Scanning electron microscope 24
Scanning electron microscope
2/18/2024 Scanning electron microscope 25
SAMPLE PREPARATION
• All samples must also be of an appropriate size to fit in the
specimen chamber and are generally mounted rigidly on a
specimen holder called a specimen stub.
• For conventional imaging in the SEM specimens must be
electrically conductive, atleast at the surface and electrically
grounded to prevent the accumulation of electrostatic charge at
the surface.
2/18/2024 Scanning electron microscope 26
1. Cleaning of the surface
• Proper cleaning of surface of the sample is important as the
surface may contain unwanted deposists, such as silt, dust,
detritus, media components or other contaminents etc or any
experiment that may have been conducted prior to SEM sample
preparation
2/18/2024 Scanning electron microscope 27
2. Stabilizing the specimen
• Stabilisation is typically done with fixatives.
• Fixation can be achieved for example by perfusion,
microinjection, immersions or with vapours using various
fixatives including aldehydes, osmium tetroxide, tannic acid or
thiocarbohydrazide.
3. Rinsing the specimen
• After the fixation step, samples must be rinsed in order to
remove the excess fixative.
2/18/2024 Scanning electron microscope 28
4. Dehydrating the specimen
• Dehydration process of biological sample needs to be done very
carefully.
• It is typically performed with either a graded series of acetone or
ethanol.
2/18/2024 Scanning electron microscope 29
5. Drying the specimen
• The specimen must be dry or the sample will be destroyed in the
electron microscope chamber.
• Many electron microscopiste consider a procedure called the
critical point drying (CPD) as gold standard for SEM specimen
drying.
• Carbon dioxide is removed after its transition from the liquid to
the gas phase at the critical point, and the specimen is dried
without structural damage.
2/18/2024 Scanning electron microscope 30
6. Mounting the specimen
• After the prior procedures specimen must be mounted on a
holder that can be inserted into the SEM.
• Samples are typically mounted on metallic (aluminium) stubs
using a double - sticky tape.
2/18/2024 Scanning electron microscope 31
7. Coating the specimen
• The idea of coating the specimen is to increase its
conductivity in the SEM and to prevent the buildup of
high voltage charges on the specimen by conducting the
charge to ground.
• Typically specimen are coated with a thin layer of
approximately 20nm to 30nm of a conductive metal (Eg –
gold, platinum)
2/18/2024 Scanning electron microscope 32
2/18/2024 Scanning electron microscope 33
2/18/2024 Scanning electron microscope 34
ADVANTAGES OF USING SEM OVER OM
MAGNIFICATION DEPTH OF FIELD RESOLUTION
OM: 4X – 1400X 0.5 mm 0.2 mm
SEM: 10X – 500Kx 30 mm 1.5 nm
SEM has a large field of depth, which allows a large amount to be
focus at one time and produces an image that is as good
representation of the 3D sample.
2/18/2024 Scanning electron microscope 35
CHARACTERISTIC INFORMATION: SEM
• TOPOGRAPHY –
• The surface texture of an object or how it looks
• Its texture
• Direct relation between these features and material properties.
• MORPHOLOGY –
• The shape and size of the particles making up the object.
• Direct relation between these features and material properties.
• COMPOSITION –
• Direct relationship between composition and material properties.
• CRYSTALLOGRAPHY – How the atoms are arranged in an atom.
2/18/2024 Scanning electron microscope 36
Identification of fracture mode
SEM micrography of fractured surface of two BaTiO3 samples.
2/18/2024 Scanning electron microscope 37
HOW FINE CAN YOU SEE ?
2/18/2024 Scanning electron microscope 38
35X
2/18/2024 Scanning electron microscope 39
200X
2/18/2024 Scanning electron microscope 40
1000X
2/18/2024 Scanning electron microscope 41
5000X
2/18/2024 Scanning electron microscope 42
35000X
The images
created without
light waves are
rendered black
and white.
2/18/2024 Scanning electron microscope 43
SEM – Stamens and pollens
2/18/2024 Scanning electron microscope 44
What does it looks like….
AFM Cantilever Tip Ant Head Blood Cells
Diamond Thin Film
(Numerous Multifaceted Micro-
crystals)
Microstructure of a plain carbon
steel that contains 0.44 wt% of
carbon
Calcium Phosphate
Crystal
45
2/18/2024 Scanning electron microscope 46
Range of applications
• Examination of surface morphology (including stero
imagining).
• Analysis and identification of surface and airborne
contamination.
• Powder morphology, particle size and analysis
• Welding technology.
• Identification and elimination of corrosion and
oxidisation problems.
2/18/2024 Scanning electron microscope 47
ADVANTAGES
• Crystallography
• Topography and morphology
• Orientation of grains
• In –situ experiments
2/18/2024 Scanning electron microscope 48
DISADVANTAGES
• It is costly.
• Highly qualified experts are needed to operate the SEM.
• Usually it require surface stain-coating with metals for electron
conducting.
• Metallic stain-coating is needed to get accurate image of Sample particles.
2/18/2024 Scanning electron microscope 49
• Detection of particle size of the
Shodhita
Bhavita
Marita
Bhasmas
• In 3 dimension image
Application in the field (RS & BK)
2/18/2024 Scanning electron microscope 50
RESEARCH WORKS
2/18/2024 Scanning electron microscope 51
• Dr. Shrikanta Sherikar
• Guide : Dr. P.G.Jadar
• Title: Screening of free radical scavenging
activity and immuno-modulatory effect of
Swarna makshika bhasma.
2/18/2024 Scanning electron microscope 52
• Dr. Ajay Chawan
• Guide: Dr. R S Hiremath
• Title: Immuno modulatory study of
Swarna bindu prashana in albino rats
2/18/2024 Scanning electron microscope 53
2/18/2024 Scanning electron microscope 54
• In this study a small pellet of sample of tarakeshwara rasa
was kept in desicator for drying.
• After desiccation the sample was subjected for carbon
coating and then was placed over the specimen holder to
observe under microscope at 5k, 10k X resolutions
2/18/2024 Scanning electron microscope 55
2/18/2024 Scanning electron microscope 56
2/18/2024 Scanning electron microscope 57
• This instrument is widely used in the pharmaceutical
and biological assay.
• In Rasashastra & BK it is used to detect partical size in
high magnification with greater resolution.
CONCLUSION
2/18/2024 Scanning electron microscope 58
OWN VIEW
• The combination of higher magnification, lager depth of field,
greater resolution, compositional and crystallographic
information makes the SEM one of the most heavily used
instrument in academic/research areas and industry.
2/18/2024 Scanning electron microscope 59
INSTRUMENT COST
• 13 Lakhs – 20 Lakhs
2/18/2024 Scanning electron microscope 60
THANK YOU

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Scanning electron microscope - SEM , Its applicability in rasashastra

  • 1. INSTRUMENTAL SEMINAR SEM - SCANNING ELECTRON MICROSCOPE Dr. Madduru Muni Haritha 1st year M.D Scholar Department of Rasashastra and Bhaishajya Kalpana KLE SHRI B.M.K Ayurveda Mahavidyalaya, Belagavi 2/18/2024 Scanning electron microscope 1
  • 2. CONTENTS • History • Introduction • Electron microscopy • Signals produced by SEM • Working principal • Magnification • Sample preparation • Application • Advantages • Disadvantages • Research articles • Conclusion • Own view 2/18/2024 Scanning electron microscope 2
  • 3. HISTORY • A German scientist ‘Max Knoll’ built the first scanning microscope in 1935. • In 1937 ‘Manfred von Ardenne’ invented a microscope with high resolution. • SEM was further developed by Prof. Charles Oatley and his student Gary steward in 1965 at Cambridge instrument company as “Stereoscan” 2/18/2024 Scanning electron microscope 3
  • 4. INTRODUCTION • The scanning electron microscope is a type of electron microscope that images the sample surface by scanning it with a high - energy beam of electrons in a raster scan pattern. (Rectangular pattern of image capture and reconstruction of it in a monitor). • The electrons interact with the atoms that make up the sample producing signals that contain information about the samples surface topography, composition and other properties such as electrical conductivity 2/18/2024 Scanning electron microscope 4
  • 5. ELECTRON MICROSCOPY • An electron microscope is a type of microscope that uses a particle beam of electrons to illuminate a specimen and creates a high magnified image. • Electron microscope have a much greater resolving power than light microscopes that uses electromagnetic radiation and can obtain much “higher magnifications upto 2 million times, while the best light microscopes are limited to magnifications to 2000 times” 2/18/2024 Scanning electron microscope 5
  • 6. SIGNALS PRODUCED BY SEM • Secondary electrons • Back – scattered electrons • Characteristic x rays • Light (cathodoluminescence) • Specimen current and transmitted electrons 2/18/2024 Scanning electron microscope 6
  • 7. Secondary electron detector • Secondary electron detectors are common in all SEM’s but it is rare that a single machine would have detectors for all possible signals. • The signals here results from interactions of the electron beam with atoms at or near the surface of the sample. 2/18/2024 Scanning electron microscope 7
  • 8. 2/18/2024 Scanning electron microscope 8 SEM WORKING PRINCIPAL
  • 9. Electron - Solid Interactions  When an electron beam strikes a sample, large number of signals are generated. 2/18/2024 Scanning electron microscope 9
  • 10. Contd…. • In most common and standard detection mode, secondary electron imaging or SEI, the SEM can produce very high resolution images of a surface, revealing details about less than 1 to 5 nm in size. • Due to very narrow electron beam, SEM micrographs have a large depth of field yielding a characteristic 3D appearance useful for understanding the surface structure of a sample. 2/18/2024 Scanning electron microscope 10
  • 11. 2/18/2024 Scanning electron microscope 11 Scanning process and image formation • In a typical SEM, an electron beam is thermionically emitted from an electron gun fitted with a tungsten filament cathode. Why only tungsten is used ? • Tungsten is normally used in thermionic electron guns because it has the highest melting point and lowest vapour pressure of all metals, thereby allowing it to be heated for electron emission, and because of its low cost.
  • 12. 2/18/2024 Scanning electron microscope 12 Electron Gun
  • 13. 2/18/2024 Scanning electron microscope 13 Contd… • The electron beam generated, which typically has an energy ranging from a few hundred eV to 40k eV is focoused by one or two condenser lenses to a spot about 0.4nm to 5nm in diameter. • The beam passes through pairs of scanning coils or pairs of deflector plates in the electron column, typically in the final lens, which deflect the beam in the x and y axis so that it scans in a raster fashion over a rectangular area of the sample surface. • Electronic amplifiers of various types are used to amplify the signals which are displayed as variations in brightness on a cathode ray tube(CRT).
  • 14. 2/18/2024 Scanning electron microscope 14 MAGNIFICATION • The electron gun can generate a beam with sufficiently small diameter, SEM in principal, work entirely without condenser or objective lenses, although it might not be very versatile or achieve very high resolution. • The image may be captured by photography from a high resolution cathode ray tube, but in modern machines is digitally captured and displayed on a computer monitor and saved to a computer hard disc. • Magnification in a SEM can be controlled over a range of upto 6 orders of magnitude from about 10 to 5000,000 times.
  • 15. 2/18/2024 Scanning electron microscope 15 Contd… • Unlike optical and transmission electron microscopes, image magnification in the SEM is not a function of the power of objective lens. • SEM may have condenser and objective lenses, but their function is to focus the beam to a spot, and not to image the specimen. • Assuming that the display screen has a fixed size, higher magnification results from reducing the size of the raster on specimen, and vice versa.
  • 16. 2/18/2024 Scanning electron microscope 16 INSTRUMENTATION 1. A column which generates a beam of electrons. 2. A specimen chamber where the electron beam interacts with the sample. 3. Detectors to monitor the different signals that result from the electron beam /sample interaction. 4. Monitor - A viewing system that builds an image from the detector signal.
  • 17. 2/18/2024 Scanning electron microscope 17 A LOOK INSIDE THE COLUMN
  • 18. 2/18/2024 Scanning electron microscope 18 Electron detection and sample stage Sample stage
  • 19. 2/18/2024 Scanning electron microscope 19 • SEM is an incredible tool for seeing the unseen worlds of microspace. • SEM creates the magnified images by using electrons instead of light waves.
  • 20. 2/18/2024 Scanning electron microscope 20 • An electron gun at the top emits a beam of high energy electrons. This beam travels downwards through a series of magnetic lenses designed to focus the electrons to a very fine spot.
  • 21. 2/18/2024 Scanning electron microscope 21 • Near the bottom, a set of scanning coils move the focused beam back and forth across the specimen row by row.
  • 22. 2/18/2024 Scanning electron microscope 22 • As the electron beam hits each spot on the sample, secondary electrons are knocked loose from its surface. A detector counts these electrons and sends signals to an amplifier.
  • 23. 2/18/2024 Scanning electron microscope 23 • The final image is built up from the number of electrons emitted from each spot on the sample.
  • 24. 2/18/2024 Scanning electron microscope 24 Scanning electron microscope
  • 25. 2/18/2024 Scanning electron microscope 25 SAMPLE PREPARATION • All samples must also be of an appropriate size to fit in the specimen chamber and are generally mounted rigidly on a specimen holder called a specimen stub. • For conventional imaging in the SEM specimens must be electrically conductive, atleast at the surface and electrically grounded to prevent the accumulation of electrostatic charge at the surface.
  • 26. 2/18/2024 Scanning electron microscope 26 1. Cleaning of the surface • Proper cleaning of surface of the sample is important as the surface may contain unwanted deposists, such as silt, dust, detritus, media components or other contaminents etc or any experiment that may have been conducted prior to SEM sample preparation
  • 27. 2/18/2024 Scanning electron microscope 27 2. Stabilizing the specimen • Stabilisation is typically done with fixatives. • Fixation can be achieved for example by perfusion, microinjection, immersions or with vapours using various fixatives including aldehydes, osmium tetroxide, tannic acid or thiocarbohydrazide. 3. Rinsing the specimen • After the fixation step, samples must be rinsed in order to remove the excess fixative.
  • 28. 2/18/2024 Scanning electron microscope 28 4. Dehydrating the specimen • Dehydration process of biological sample needs to be done very carefully. • It is typically performed with either a graded series of acetone or ethanol.
  • 29. 2/18/2024 Scanning electron microscope 29 5. Drying the specimen • The specimen must be dry or the sample will be destroyed in the electron microscope chamber. • Many electron microscopiste consider a procedure called the critical point drying (CPD) as gold standard for SEM specimen drying. • Carbon dioxide is removed after its transition from the liquid to the gas phase at the critical point, and the specimen is dried without structural damage.
  • 30. 2/18/2024 Scanning electron microscope 30 6. Mounting the specimen • After the prior procedures specimen must be mounted on a holder that can be inserted into the SEM. • Samples are typically mounted on metallic (aluminium) stubs using a double - sticky tape.
  • 31. 2/18/2024 Scanning electron microscope 31 7. Coating the specimen • The idea of coating the specimen is to increase its conductivity in the SEM and to prevent the buildup of high voltage charges on the specimen by conducting the charge to ground. • Typically specimen are coated with a thin layer of approximately 20nm to 30nm of a conductive metal (Eg – gold, platinum)
  • 34. 2/18/2024 Scanning electron microscope 34 ADVANTAGES OF USING SEM OVER OM MAGNIFICATION DEPTH OF FIELD RESOLUTION OM: 4X – 1400X 0.5 mm 0.2 mm SEM: 10X – 500Kx 30 mm 1.5 nm SEM has a large field of depth, which allows a large amount to be focus at one time and produces an image that is as good representation of the 3D sample.
  • 35. 2/18/2024 Scanning electron microscope 35 CHARACTERISTIC INFORMATION: SEM • TOPOGRAPHY – • The surface texture of an object or how it looks • Its texture • Direct relation between these features and material properties. • MORPHOLOGY – • The shape and size of the particles making up the object. • Direct relation between these features and material properties. • COMPOSITION – • Direct relationship between composition and material properties. • CRYSTALLOGRAPHY – How the atoms are arranged in an atom.
  • 36. 2/18/2024 Scanning electron microscope 36 Identification of fracture mode SEM micrography of fractured surface of two BaTiO3 samples.
  • 37. 2/18/2024 Scanning electron microscope 37 HOW FINE CAN YOU SEE ?
  • 38. 2/18/2024 Scanning electron microscope 38 35X
  • 39. 2/18/2024 Scanning electron microscope 39 200X
  • 40. 2/18/2024 Scanning electron microscope 40 1000X
  • 41. 2/18/2024 Scanning electron microscope 41 5000X
  • 42. 2/18/2024 Scanning electron microscope 42 35000X The images created without light waves are rendered black and white.
  • 43. 2/18/2024 Scanning electron microscope 43 SEM – Stamens and pollens
  • 45. What does it looks like…. AFM Cantilever Tip Ant Head Blood Cells Diamond Thin Film (Numerous Multifaceted Micro- crystals) Microstructure of a plain carbon steel that contains 0.44 wt% of carbon Calcium Phosphate Crystal 45
  • 46. 2/18/2024 Scanning electron microscope 46 Range of applications • Examination of surface morphology (including stero imagining). • Analysis and identification of surface and airborne contamination. • Powder morphology, particle size and analysis • Welding technology. • Identification and elimination of corrosion and oxidisation problems.
  • 47. 2/18/2024 Scanning electron microscope 47 ADVANTAGES • Crystallography • Topography and morphology • Orientation of grains • In –situ experiments
  • 48. 2/18/2024 Scanning electron microscope 48 DISADVANTAGES • It is costly. • Highly qualified experts are needed to operate the SEM. • Usually it require surface stain-coating with metals for electron conducting. • Metallic stain-coating is needed to get accurate image of Sample particles.
  • 49. 2/18/2024 Scanning electron microscope 49 • Detection of particle size of the Shodhita Bhavita Marita Bhasmas • In 3 dimension image Application in the field (RS & BK)
  • 50. 2/18/2024 Scanning electron microscope 50 RESEARCH WORKS
  • 51. 2/18/2024 Scanning electron microscope 51 • Dr. Shrikanta Sherikar • Guide : Dr. P.G.Jadar • Title: Screening of free radical scavenging activity and immuno-modulatory effect of Swarna makshika bhasma.
  • 52. 2/18/2024 Scanning electron microscope 52 • Dr. Ajay Chawan • Guide: Dr. R S Hiremath • Title: Immuno modulatory study of Swarna bindu prashana in albino rats
  • 54. 2/18/2024 Scanning electron microscope 54 • In this study a small pellet of sample of tarakeshwara rasa was kept in desicator for drying. • After desiccation the sample was subjected for carbon coating and then was placed over the specimen holder to observe under microscope at 5k, 10k X resolutions
  • 57. 2/18/2024 Scanning electron microscope 57 • This instrument is widely used in the pharmaceutical and biological assay. • In Rasashastra & BK it is used to detect partical size in high magnification with greater resolution. CONCLUSION
  • 58. 2/18/2024 Scanning electron microscope 58 OWN VIEW • The combination of higher magnification, lager depth of field, greater resolution, compositional and crystallographic information makes the SEM one of the most heavily used instrument in academic/research areas and industry.
  • 59. 2/18/2024 Scanning electron microscope 59 INSTRUMENT COST • 13 Lakhs – 20 Lakhs
  • 60. 2/18/2024 Scanning electron microscope 60 THANK YOU