Справочник Пользователя для Hitachi Microscope & Magnifier S-4800
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3.2 Specimen Setting and Specimen Exchange
3.2.1 Cautions on Specimen Preparation
During specimen preparation, observe the followings.
(1) Use clean gloves when exchanging specimens. Holding the specimen or specimen stub with
3.2.1 Cautions on Specimen Preparation
During specimen preparation, observe the followings.
(1) Use clean gloves when exchanging specimens. Holding the specimen or specimen stub with
bare hands should be avoided.
(2) Avoid using an excessive amount of conductive paste to fix a specimen on the specimen stub.
Ensure that the paste has dried before placing the specimen in the chamber.
(3) Select the correct specimen stub for each specimen.
(4) When using double-sided adhesive tape to fix a specimen to the stub, use the least amount
to minimize out-gassing. The use of double-sided adhesive tape may also cause specimen
drift.
drift.
3.2.2 Specimen Preparation for Materials
The method of specimen preparation varies with materials. Below are preparation methods for
typical types of specimens.
(1) Conductive specimens such as metals:
These types of specimens can be observed without preparation. However, coating with heavy
metals by using a vacuum evaporator, an ion sputtering or magnetron sputtering unit may
result in better contrast.
metals by using a vacuum evaporator, an ion sputtering or magnetron sputtering unit may
result in better contrast.
(2) Non-conductive specimens such as semiconductors, fibrous specimens and polymeric
materials:
Coating with conductive materials is recommended. To observe these kinds of specimens
without a conductive coating use low accelerating voltages (1kV or lower). However, coated
particles may be more visible at higher magnifications.
Coating with conductive materials is recommended. To observe these kinds of specimens
without a conductive coating use low accelerating voltages (1kV or lower). However, coated
particles may be more visible at higher magnifications.
(3) Biological specimens:
After dehydration, dry the specimen by using a method such as critical point drying, freeze
drying or other drying techniques, then coat the specimen with conductive material. A
cryogenic system is available as an option.
drying or other drying techniques, then coat the specimen with conductive material. A
cryogenic system is available as an option.
(4) X-ray analysis specimens:
Generally, polish the surface of the specimen, then fix it to the specimen stub using carbon
paste. Non-conductive specimens should be coated with carbon using a vacuum evaporator.
paste. Non-conductive specimens should be coated with carbon using a vacuum evaporator.