The copper mesh usually used in transmission electron microscope experiments is the carrier mesh for carrying samples. If the carrier net is made of copper, it is called copper net; If it is made of nickel, molybdenum, gold and nylon, it is called nickel mesh, molybdenum mesh, gold mesh and nylon mesh accordingly.
The carrier net is used alone, also called "bare net". It is mainly used for the preparation of biological samples, and can cooperate with slicer to fish samples in the sink with bare net. Then spray carbon or gold, and then enter the electron microscope for observation. When preparing most TEM samples, in order to ensure that the samples can be carried on the "carrier net", an organic film called "supporting film" will be covered on the "carrier net". This carrier net with supporting film is called "carrier net supporting film".
When the sample comes into contact with the supporting film of the carrier net, it will be firmly adsorbed on the supporting film and will not slip out of the holes of the carrier net. So as to be observed under an electron microscope.
Extended data:
With the addition of accessories, the function of transmission electron microscope can be developed from observing internal tissue morphology (TEM) and in-situ electron diffraction analysis (Diff) to in-situ composition analysis (EDS, EELS), surface morphology observation (SED, BED) and transmission scanning image (STEM).
Combined with the design of the sample table as a high-temperature table, a low-temperature table and a stretching table, TEM can also observe the dynamic changes of the structure and composition of the sample in the heating state, the low-temperature cooling state and the stretching state, which further broadens the functions of TEM.
The broadening of the function of transmission electron microscope means that one instrument can carry out many kinds of analysis without changing samples, especially the comprehensive analysis of morphology, crystal structure and composition (valence state) of the same micro-area position.
Commonly referred to as "carbon support film". Precisely speaking, micro-grid is a kind of supporting film, which is a kind of micropore specially made on the film when it is made, so it is also called "micro-grid supporting film", and it is also a supporting film sprayed with carbon, with a general film thickness of 15-20nm. It is mainly to carry the sample on the edge of the micropore of the supporting film, so that the sample can be observed without the film. The main purpose of no film is to improve image contrast. Therefore, tubes, rods, nano-aggregates, etc. are observed. "Microgrid" supporting membrane is commonly used, and the effect is very good.
Carbon support film and micro-grid with holes are often used to salvage samples in the test, but there is an ultra-thin carbon film on the micro-grid with holes. For high resolution, it is best to control the thickness of the sample below 20nm, so the powder with a diameter less than 20 nm is generally fished out directly. The larger the particle, the finer the ions after embedding.
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