China
Africa
Explore chapters and articles related to this topic
Electrical, Physical, and Chemical Characterization
Published in Robert Doering, Yoshio Nishi, Handbook of Semiconductor Manufacturing Technology, 2017
Dieter K. Schroder, Bruno W. Schueler, Thomas Shaffner, Greg S. Strossman
Particle-induced x-ray emission (PIXE) is an elemental analysis technique that detects x-rays that are induced by the collision of the primary particles with the atoms in the sample. The interaction causes the removal of core electrons leading to the emission of x-rays with specific energies when outer shell electrons drop to fill the core shell vacancies. The x-ray energies are independent of the excitation process and are element specific. Since these x-rays are produced constantly during an RBS analysis, PIXE requires only that an RBS instrument be fitted with a suitable x-ray detector. As an accessory on RBS instruments, PIXE is useful for heavy element identification when the elements of interest have only small differences in RBS energies but distinct differences in PIXE spectra. There are also dedicated PIXE instruments; however, these typically use H+ bombardment instead of the He+ used in RBS.
Evolution of Rutherford’s ion beam science to applied research activities at GNS Science
Published in Journal of the Royal Society of New Zealand, 2021
John V. Kennedy, William Joseph Trompetter, Peter P. Murmu, Jerome Leveneur, Prasanth Gupta, Holger Fiedler, Fang Fang, John Futter, Chris Purcell
Particle induced X-ray emission commonly known as PIXE, is used to analyse for elements using X-rays. This is achieved by exposing a sample to a beam of particles. For PIXE we generally use a proton beam accelerated with typically 2.5 million volts from a van-de-Graaff accelerator. When protons in the beam interact with atoms in the sample, atomic electrons are ejected from orbitals and X-rays are emitted as other electrons fill the vacancies. The X-ray energy spectrum consists of a continuous background together with the characteristic X-ray peaks from atoms present in the specimen. While all elements heavier than helium emit K X-rays, elements heavier than strontium are usually detected via their lower energy L X-rays because the production of L X-rays becomes more significant than their K X-rays. The maximum ionisation cross-section occurs when the incident ion and the target shell electron have similar velocities.