Modifications Needed for Performing High-Resolution Cryosem in a Hitachi S-4700 Fesem Using an Emitech K1250 Cryo-Preparation System

Cryo-techniques have been successfully used in scanning electron microscopy (SEM). They are especially promising for high-resolution SEM to improve specimen preservation and reduce radiation damage [1, 2]. A number of cryo-preparation systems are commercially available for SEM, however, our experience has shown that modifications are needed to perform highresolution imaging (>50,000x).Emitech K1250 system consists of a sample preparation chamber, control unit, and cryo-stage. Magnetron sputter coating is standard and electron-beam evaporation is optional. A vacuum transfer device facilitates the sample transfer between the preparation chamber and the SEM to prevent contamination. The Emitech cryo-stage replaces the Hitachi S-4700 standard stage and the cryo-stage temperature is monitored and controlled by the Emitech control unit.The specimen is mounted on a sample holder that mounts to the cryo-stage. Therefore, the distance from the specimen to cryo-stage, the thermal capacity of the sample holder, and the thermal contact between them will affect the actual temperature of the specimen.

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Magnetron sputter coating for ultra high resolution Scanning Electron Microscopy (Simultaneous coating of platinum and tungsten using a magnetron sputter coater)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152379 ◽

1989 ◽

Vol 47 ◽

pp. 80-81

Author(s):

K. Ogura ◽

S. Adachi ◽

T. Satoh ◽

T. Watabe ◽

M. M. Kersker

Keyword(s):

High Resolution ◽

Carbon Film ◽

Metal Coating ◽

Specimen Surface ◽

Gas Atmosphere ◽

Sputter Coating ◽

Resolution Imaging ◽

Magnetron Sputter ◽

Ar Gas ◽

Scanning Electron

The resolution of the SEM has been remarkably improved by means of the in-lens SEM with a field emission gun. Consequently, the thin metal coating on the specimen surface for ultra high resolution imaging has become very important. In the age of imaging with 2-3nm resolution at 100,000x magnification, a very thin platinum (Pt) coating on the specimen surface using the magnetron sputter coater has yielded successful results. However, in an ultra high resolution scanning electron microscope with better than 1nm resolution at higher than 200,000: magnification, the fine granularity of magnetron sputter coating of Inra thick Pt will be observed on the specimen surface. Therefore, a thinner metal coating with smaller grain size than that of Pt is strongly required. Recently, we tried tungsten (W) coating on many variety of specimens in argon (Ar) gas atmosphere by using a magnetron sputter coater. Using a W coated carbon film, the granularity of W was examined by both an UHR-SEM and a TEM at a minimum magnification of 250,000x.

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High-Vacuum Evaporation and a Cryostage to Observe Fractured Yeast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103346 ◽

1988 ◽

Vol 46 ◽

pp. 256-257

Author(s):

William P. Wergin ◽

Eric F. Erbe ◽

Eugene L. Vigil

Keyword(s):

Electron Microscope ◽

Low Temperature ◽

Standard Specimen ◽

High Vacuum ◽

Specimen Holder ◽

Sputter Coating ◽

Fresh Frozen ◽

Gain Access ◽

Scanning Electron ◽

Transfer Device

Investigators have long realized the potential advantages of using a low temperature (LT) stage to examine fresh, frozen specimens in a scanning electron microscope (SEM). However, long working distances (W.D.), thick sputter coatings and surface contamination have prevented LTSEM from achieving results comparable to those from TEM freeze etch. To improve results, we recently modified techniques that involve a Hitachi S570 SEM, an Emscope SP2000 Sputter Cryo System and a Denton freeze etch unit. Because investigators have frequently utilized the fractured E face of the plasmalemma of yeast, this tissue was selected as a standard for comparison in the present study.In place of a standard specimen holder, a modified rivet was used to achieve a shorter W.D. (1 to -2 mm) and to gain access to the upper detector. However, the additional height afforded by the rivet, precluded use of the standard shroud on the Emscope specimen transfer device. Consequently, the sample became heavily contaminated (Fig. 1). A removable shroud was devised and used to reduce contamination (Fig. 2), but the specimen lacked clean fractured edges. This result suggested that low vacuum sputter coating was also limiting resolution.

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Hetero-Epitaxy of Group Va Metals on Sapphire

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095716 ◽

1972 ◽

Vol 30 ◽

pp. 492-493

Author(s):

J. E. O'Neal ◽

J. J. Bellina ◽

B. B. Rath

Keyword(s):

Thermal Contact ◽

High Vacuum ◽

Electron Beam Evaporation ◽

Ultra High Vacuum ◽

Backing Plate ◽

Sapphire Substrates ◽

Deposition Parameters ◽

Polishing Damage ◽

Reflection Electron Diffraction

Thin films of the bcc metals vanadium, niobium and tantalum were epitaxially grown on (0001) and sapphire substrates. Prior to deposition, the mechanical polishing damage on the substrates was removed by an in-situ etch. The metal films were deposited by electron-beam evaporation in ultra-high vacuum. The substrates were heated by thermal contact with an electron-bombarded backing plate. The deposition parameters are summarized in Table 1.The films were replicated and examined by electron microscopy and their crystallographic orientation and texture were determined by reflection electron diffraction. Verneuil-grown and Czochralskigrown sapphire substrates of both orientations were employed for each evaporation. The orientation of the metal deposit was not affected by either increasing the density of sub-grain boundaries by about a factor of ten or decreasing the deposition rate by a factor of two. The results on growth epitaxy are summarized in Tables 2 and 3.

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Enlarged Sample Holder for Optical AFM Imaging: Millimeter Scanning with High Resolution

2010 First International Conference on Sensor Device Technologies and Applications ◽

10.1109/sensordevices.2010.42 ◽

2010 ◽

Cited By ~ 1

Author(s):

A. Sinno ◽

P. Ruaux ◽

L. Chassagne ◽

S. Topcu ◽

Y. Alalyli ◽

...

Keyword(s):

High Resolution ◽

Sample Holder ◽

Afm Imaging

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Magnetron sputter coating of microspherical substrates

Journal of Vacuum Science and Technology ◽

10.1116/1.569906 ◽

1979 ◽

Vol 16 (2) ◽

pp. 197-199 ◽

Cited By ~ 12

Author(s):

A. T. Lowe ◽

C. D. Hosford

Keyword(s):

Sputter Coating ◽

Magnetron Sputter

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Development of an effective sample transfer device for biomarker detection in nasal secretions

Analytical Biochemistry ◽

10.1016/j.ab.2019.113404 ◽

2019 ◽

Vol 585 ◽

pp. 113404

Author(s):

Young Ju Lee ◽

Jae-Chul Lee ◽

Young Gyu Eun ◽

Gi-Ja Lee

Keyword(s):

Biomarker Detection ◽

Nasal Secretions ◽

Sample Transfer ◽

Transfer Device

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A multiple sample transfer device for use with surface analytical systems

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.572374 ◽

1984 ◽

Vol 2 (3) ◽

pp. 1395-1396 ◽

Cited By ~ 4

Author(s):

G. C. Nelson ◽

L. R. Shapnek

Keyword(s):

Multiple Sample ◽

Sample Transfer ◽

Transfer Device

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High-Resolution Field Emission Scanning Electron Microscopy (FESEM) Imaging of Cellulose Microfibril Organization in Plant Primary Cell Walls

Microscopy and Microanalysis ◽

10.1017/s143192761701251x ◽

2017 ◽

Vol 23 (5) ◽

pp. 1048-1054 ◽

Cited By ~ 13

Author(s):

Yunzhen Zheng ◽

Daniel J. Cosgrove ◽

Gang Ning

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cell Wall ◽

High Resolution ◽

Field Emission ◽

Cell Walls ◽

Cellulose Microfibrils ◽

Critical Point Drying ◽

Sputter Coating ◽

Scanning Electron

AbstractWe have used field emission scanning electron microscopy (FESEM) to study the high-resolution organization of cellulose microfibrils in onion epidermal cell walls. We frequently found that conventional “rule of thumb” conditions for imaging of biological samples did not yield high-resolution images of cellulose organization and often resulted in artifacts or distortions of cell wall structure. Here we detail our method of one-step fixation and dehydration with 100% ethanol, followed by critical point drying, ultrathin iridium (Ir) sputter coating (3 s), and FESEM imaging at a moderate accelerating voltage (10 kV) with an In-lens detector. We compare results obtained with our improved protocol with images obtained with samples processed by conventional aldehyde fixation, graded dehydration, sputter coating with Au, Au/Pd, or carbon, and low-voltage FESEM imaging. The results demonstrated that our protocol is simpler, causes little artifact, and is more suitable for high-resolution imaging of cell wall cellulose microfibrils whereas such imaging is very challenging by conventional methods.

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