Used PHILIPS / FEI Gun unit for Tecnai F30 #293669732 for sale

FEI Gun unit for the Tecnai F30 scanning electron microscope is an ultra-high vacuum cathode unit that consists of multiple components that allow for improved electron beam stability. The gun assembly is composed of a thermionic cathode, filament, anode, acceleration electrode and grid, insulators, sample preparation holders and the Gun Unit itself. The thermionic cathode is made of an oxide coated tungsten material, and is housed in a welded stainless steel assembly. It is responsible for generating the electrons required to illuminate the sample. These electrons are produced when the heated tungsten material is exposed to high vacuum pressure. The filament is used to heat the cathode and prepare it for electron-beam production. It uses a specially designed filament current that is stabilized using an external circuit. The acceleration electrode is located between the thermionic cathode and the sample. It accelerates the electrons from low voltage to high voltages suitable for analyzing the sample. The anode, also known as the collector, is a positively charged plate located opposite the cathode. It collects the electrons produced and is used to provide a reference for beam current measurement. The grid is also known as the Wehnelt cylinder and is used to control the shape of the electron beam. It is used to ensure uniform illumination on the sample surface. The gun unit is designed to be an ultra-high vacuum (UHV) environment, where all components within the gun are isolated to prevent contamination of the sample. The insulators are utilized to provide electrical insulation between the anode and cathode, and also from the other system components. They are made of electrically stable materials such as Teflon or Kapton. Sample preparation holders, which consist of a spring loaded mechanism, are used to mount the samples in the electron beam. Lastly, the gun unit itself includes power supplies and additional electron optics for imaging and other specimen observations. Combined, these components work together to produce a stable electron beam that is suitable for scanning electron microscopy analysis of samples. The gun unit is capable of producing a variety of beam current levels and voltage settings. This allows users to perform detailed analyses of sample surfaces with the highest quality of imaging available.