Transmission electron microscopy (TEM)
Are microscopes that view samples and create a vastly expanded image through the use of an electron particle beam. TEMs can magnify objects approximately 2 million times.
TEMs Working Principle:
In addition to making an image, TEMs need a high voltage beam of electrons. An electron emitter just at the head of a TEM releases electrons that go through the vacuum tube of the microscope. Instead of a single-lens reflex to focus the light, the TEM utilizes an electro-magnetic lens to concentrate the electrons through an extremely tiny beam. This beam then travels into the very thin specimen, and the electrons can deflect or strike a light source at the bottom of the microscope.
Preparation of Specimens:
A tiny enough TEM sample can transfer more electrons to generate an image with reduced power loss. As a result, sample preparation is a necessary feature of TEM analysis. A standard sequence of preparation processes for most flexible electronics includes acoustic disk slicing, puffiness, and ion milling. Slight discoloration is a preparatory process that results in a sample with a reduced center of the image and a thick enough outside edge to facilitate ease manipulation. Traditionally, particle grinding is the ultimate stage of sample processing. The use of high – voltage power pushes ionized argon atoms to the sample surface throughout this procedure. As a result of molecular diffusion, ionic bombardment on the sample surface material removal.
Advantages:
- TEMs can produce high-quality images.
- TEMs offer a variety of applications in high - spatial domains such as research, education, and industry.
- When used in conjunction with EDS and EELS, TEMs can offer chemical and atomic-bonding data.
- The maximum resolution in the microscopy region is obtained by TEMs.
- Surface characteristics, shape, size, as well as composition may all be determined using TEMs.
