Scanning electron microscopy sample etching

W. Trochimezuk, Changes in Structure of Polyethylene/Styrene divinyl benzene System, presented at the Structure and Properties of Polymer Networks, Jablonna, Poland, April 1979. Polyethylene/poly(styrene-co-divinyl benzene) semi-II IPNs. Scanning electron microscopy of etched samples. Morphology goes from PS discontinuous to PS continuous as DVB level is increased passed 2%. Polyethylene crystal size is decreased with increasing DVB content. 

Our investigation of sNPS showed that the samples prepared by the chemical etching method described above have consistent photoluminescence, conductivity and photoconductivity properties, which have remained unchanged over 5 years. sNPS structure was investigated by scanning electronic microscopy (Fig. 9.1). 

One major problem of all these techniques is the sensitivity in the parameter selected to detect the presence of inhomogeneities. With visible light for example, inhomogeneous samples can appear transparent if the difference in the refractive index between the phases is less than 0.01. Staining (in the case of transmission electron microscopy, TEM), or chemical etching (in the case of scanning electron microscopy, SEM), can be helpful in revealing the structure. 

Measurements. The morphology of the blends was studied by optical microscopy (Leitz Dialux Pol), transmission electron microscopy (Jeol 100 U), and scanning electron microscopy (Cambridge MK II). Ultramicrotome sections were made with an LKB Ultratome III. Samples for scanning electron microscopy were obtained by fracturing sheets at low temperature. The fracture surfaces were etched with a 30% potassium hydroxide solution to hydrolyse the polycarbonate phase. Stress-relaxation and tensile stress-strain experiments were performed with an Instron testing machine equipped with a thermostatic chamber. Relaxation measurements were carried out in flexion (E > 108 dyn/cm2) or in traction (E < 108 dyn/cm2). Prior to each experiment, the samples were annealed to obtain volumetric equilibrium. 

Dynamic mechanical property data were obtained using Du Pont DMA 982 instrument for structural analyses and Rheology DVE instrument for measurement of damping ability. Scanning electron microscopy was performed on samples etched with strong chromic acid. The mechanical properties were measured at 20°C by tensile test. 

Fig. 12.3. Scanning electron microscopy (SEM) image of a Si nucleus formed between the initial glass/Al and Al/a-Si interfaces (the A1 was etched off chemically). The sample was tilted by 30° to show the cross section as well as the surface, (from [27])...

Structure of alloys as well as their fracture micromechanisms was studied with scanning electron microscopy (SEM) and X-ray microanalysis with Superprobe-733 (JEOL). To reveal the inner structure of samples, deep electrolytic etching with etchant based on acetic acid was used. 

Powder morphology was investigated using a transmission electron microscope (TEM, Model JEM-IOOCXII). Crystallite size of the powders and grain size of Nd YAG ceramics calcined at different temperatures were calculaied by X-ray diffraction (XRD, model D/maxrA, using nickel-filtered Cu-Ka radiation) patterns from the Scherrer s equation. Microstructures of the fractured and the thermal etched mirror-polished surfaces of Nd YAG specimens were observed by scanning electron microscopy (SEM, Model S-4800). Densities of the samples were measured by the Archimedes draining method. 

Low-temperature sublimation has been used to prepare samples for cryo-scanning electron microscopy (SEM) analysis in order to examine herbicide particles in a water suspension. The sublimation of herbicide-containing frozen water droplets provides a suitable etching of the surface for the SEM technique. 

Prior to scanning electron microscopy (Philips SEM 505, 30 kV), an 8-nm thick gold layer was deposited on the etched sample in a sputtering device (Balzers Union, Balzers, Liechtenstein) to avoid electrostatic charging of the surface. 

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