Scanning Electron Microscope (SEM)
Location and contact information
- Location: CCNY, Marshak 022 (Supra 55 VP)
- Facility Manager: Jorge Morales
- Phone: 212 650 8591(office) Phone : 347 398 1846 (cell)
- 10:30 am to 6:30 pm
- Online Calendar
Hourly recharge rates (Effective as of 05/01/2015)
Federal Rate: $96/h
Non-Federal Rate: $144/h
CCNY (internal) Rate: $36/h
About the Facility
The Zeiss Supra 55 is a field emission SEM with a maximum resolution of 1 nm. It has the following capabilities: secondary and backscattered electron imaging in high vacuum or in variable pressure mode, scanning transmission electron microscopyimaging, electron beam lithography, energy dispersive x-ray spectrometry (EDS) andelectron backscatter diffraction (EBSD). This instrument is located in the Marshak Science Building rooom MR 022.
To start using our SEM schedule a meeting with Dr. Morales (firstname.lastname@example.org).
The Zeiss Supra 55 VP was purchased in 2008 with funding provided by the State of New York through the City University of New York (CUNY).
The scanning electron microscope (SEM) is a type of electron microscope that images the sample surface by scanning it with a high-energy beam of electrons in a raster scanpattern. The electrons interact with the atoms that make up the sample producing signals that contain information about the sample's surface topography, composition and other properties such as electrical conductivity.
The types of signals made by an SEM can include secondary electrons, back scatteredelectrons, characteristic x-rays and light (cathodoluminescence). These signals come from the beam of electrons striking the surface of the specimen and interacting with the sample at or near its surface. In its primary detection mode, secondary electronimaging, the SEM can produce very high-resolution images of a sample surface, revealing details about 1 to 5 nm in size. Due to the way these images are created,SEM micrographs have a very large depth of focus yielding a characteristic three-dimensional appearance useful for understanding the surface structure of a sample. This great depth of field and the wide range of magnifications (commonly from about 25 times to 250,000 times) are available in the most common imaging mode for specimens in the SEM, secondary electron imaging, such as the micrograph taken of pollen shown to the right. Characteristic x-rays are the second most common imaging mode for an SEM. X-rays are emitted when the electron beam removes an inner shellelectron from the sample, causing a higher energy electron to fill the shell and give off energy. These characteristic x-rays are used to identify the elemental composition of the sample. Back-scattered electrons (BSE) that come from the sample may also be used to form an image. BSE images are often used in analytical SEM along with the spectra made from the characteristic x-rays as clues to the elemental composition of the sample. (Source: Wikipedia)