SEM Laboratory
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SEM Laboratory |
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Laboratory Supervisors and Device Users |
Elif PEKEROGLU TEMURTAS E-Mail: etemurtas@adiyaman.edu.tr Web: Elif PEKEROGLU TEMURTAS |
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Erkan DOGAN E-Mail: erkandogan@adiyaman.edu.tr Web: Erkan DOGAN Phone: +90 416 2233800 - 2258 |
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Device Name |
Scanning Electron Microscope (SEM) |
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Device Brand Name and Model |
ZEISS & EVO LS 10 |
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General Information |
Scanning Electron Microscope consists of three main parts: "Optical Column", "Sample Cell" and "Imaging System". There are Electron Gun(the source of the electron beam), Anode Plate(the plate where high voltage is applied to accelerate the electrons towards the samples), Concentrator Lens(the lens is used to thin and densify the electron beam to be impacted on the sample surface), Objective Lens (the lens focuses the beam on the sample), Apertures(various diameters of apertures attached to the lens allow the electron beam to be impacted to the sample surface.) and Coils(Used for scanning the surface) in the optical column. Lens systems in this section are used to thin the electron beam with the electromagnetic field or focus it on the sample. The entire optical column and sample cell section are kept at a vacuum of 10-4 Pa. Sample Cell section; There is a sample tray where the samples to be displayed will be placed. After the samples are placed on this table and fixed, the air in the sample cell is vacuumed. This allows electrons to be dropped directly on the sample without any other deflector influence in a vacuum environment.. Detectors, detectors’ signal multipliers and magnetic coils make up the imaging system. Detectors collect a variety of electrons and radiation generated as a result of sample interference with the electron beam. magnetic coils scan the electron beam on the sample surface synchronously with the display screen. |
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Sample Preparation |
All kinds of conductive samples that are non-liquid can be examined directly with SEM. Non-conductive or semiconductor samples should be pretreated such as Au - Pd or C Coating. Using one of the coating methods, the sample is coated with a very thin (~ 3A / sec) conductive material to prepare for imaging.. Similarly, hard biological specimens such as bone, tooth, wood can be prepared for imaging by performing a coating processthe "Critical Point Dryer" method is used in the preparation of soft biological samples such as plant or animal parts, tissues because these samples contain liquid in their structure. With the critical point dryer method, the liquid content is removed without distorting the structure and shape of the sample. In this way, these soft biological samples are prepared to image |
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Usage Area |
With SEM, all kinds of metals, textiles, fibers, plastics, polymers, particles (such as sand, gravel, pollen) etc. can be examined SEM is widely used for researches;
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Preparation for SEM |
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Device Brand and Model |
Gold & Palladium Plating Device - QUORUM |
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General Information |
It ensures that the surfaces of semiconductor or non-conductive samples are thinly coated with Au & Pd in order to do better imaging. Typical coating thickness is 20 - 30 nm. The coating process increases the sample's conductivity, reducing the sample charge because higher conductivity can cause deflection of the beam falling on the sample or image distortion. Via temperature conduction, it also improves the sample's mechanical stability. Au & Pd coating increases the emission of primary and secondary electrons, helping detectors collect more imaging data. It is favoured due to its high secondary diffusion coefficient, strong heat and electron conductivity, and lack of oxidation |
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Usage Area |
In imaging, EDX, and mapping applications, it is used to prepare the sample. |
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Device Brand and Model |
Carbon Coating Device - QUORUM |
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General Information |
The C Coating process works in the same way as the Au & Pd coating process. It may be used in particular when the gold and/or palladium additive is not desired on the sample.. |
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Usage Area |
In imaging, EDX, and mapping applications, it is used to prepare the sample |
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Device Brand and Model |
Critical Point Dryer - QUORUM K850 |
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General Information |
The state-of-the-art approach for preserving sample morphology is critical point drying. Physical properties of liquid and gaseous are indistinguishable at the critical stage. Compounds which are in the critical point can be converted into the liquid or gaseous phase without crossing the interfaces between liquid and gaseous avoiding the damaging effects. The use of the critical point of water to dehydrate the samples is not feasible since any biological sample will be destroyed. To overcome this problem, water can be replaced against liquid carbon dioxide (CO2), because liquid CO2 is more appropriate for all biological applications and technically relative easy to maintain. When using CO2, the liquid and vapor phases in the sample have similar physical properties. As a result, aeration of liquid vapors across cell boundaries causes minimal sample degradation. |
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Usage Area |
In imaging, EDX, and mapping applications, it is used to prepare the sample |
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Device Brand and Model |
Sample Sanding Device - METKON Forcipol 2V |
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General Information |
Before imaging, the surface of the material is cleaned and / or sanded with the device. |
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Usage Area |
In imaging, EDX, and mapping applications, it is used to prepare the sample |
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Device Brand and Model |
Sample Cutting Device - METKON Micracut 151 |
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General Information |
It enables obtaining small materials in size by making millimetric precise cuts in the preparation of samples for imaging. |
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Usage Area |
In imaging, EDX, and mapping applications, it is used to prepare the sample |