Artifacts scanning electron microscop

Samples of microspheres were mounted on aluminum specimen mounts by means of double-faced tapes. The microspheres were fractured with razor blades to expose the internal matrix. The samples were then coated with approximately 125 of gold by pulsing the sputter coater to avoid the possibility of artifact caused by heat generation. Secondary emissive scanning electron microscopy was performed with an Amray 1600 Turbo scanning electron microscope. 

Normally the craze microstructure is not directly visible in the scanning electron microscope. Thus, an etching procedure using oxygen ions was employed to remove the plastically deformed layer at the sample surface. Control measurements on uncrazed samples showed that this procedure does not lead to artifacts. The surfaces were coated with gold to reduce surface charging. 

The practical lower limit of emulsion sizing with optical microscopy is on the order of 0.5 (xm. This limit is much lower with electron microscopy, on the order of 0.1 (xm or less with direct observation of frozen samples in a scanning electron microscope, and 0.01 xm or less with replicas and transmission electron microscopy. Sizes smaller than these lower limits can be recognized with each of these techniques, but quantification of the size distribution becomes difficult. Furthermore, at levels of about 0.01 xm, it is extremely difficult to avoid artifacts and subsequent misinterpretations. As mentioned earlier, sample preparation is an extremely important consideration in both optical and electron microscopic techniques. With optical... 

The conventional SEM measurement carried out in a vacuum has disadvantages and may also result in artifacts. Moreover, the coating can obscure the fine surface structure details of some non-electroconductive samples. In the 1980s, the environmental scanning electron microscope (ESEM) was developed, " which permits the imaging of wet systems with no prior specimen preparation. Since the sample environment can be dynamically altered, hydration... 

The main disadvantage of AFM, compared to the electron microscope, is the image size. The electron microscope can show an area on the order of millimeters by millimeters and a depth of field on the order of millimeters. The AFM can only show a maximum height on the order of micrometers and a maximum area of around 125 X 125 lm. Other disadvantages include slow scanning, having to fix samples, and artifacts. 

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