Surface Analysis Assignment Example | Topics and Well Written Essays - 1750 words - 1

Surface Analysis - Assignment Example Using a combination of electrostatic and magnetic fields which distinguishes the ions on the mass to charge ratio, these secondary ions are drawn into a mass spectrometer. By varying the strength of the magnetic field one can assess ions of different mass to charge ratios. (ii) It is capable of finding out the extent of impurity concentration present in a specimen and represents the same as a function of depth. The sensitivity of this instrument is in the range of 1 ppb (-10^13 at/cm^3). auger electrons from the material on collision. These auger electrons have specific kinetic energies which depend on the electrons emitted. This method therefore creates element maps capable of identifying chemical composition. Some of the applications of AES include This advanced technique uses x rays in dislodging electrons from specimens and these have distinct kinetic energies depending on the nature of emitted electrons. It is particularly useful in providing information regarding the type of bonds that exist between electrons. This is because any change in binding energy is reflected in the XPS spectrum chart which shows crests and troughs. The crests obviously reflect the high chemical boding energy that existed and the troughs vice versa. Its applications include This essentially consists of a tip mounted on a cantilever. The specimen is placed below this cantilever and dragged back and forth. The laser which is focussed on the cantilever bounces off the surface onto the photodiodes. As the cantilever tip moves up and down due the surface irregularities of the specimen, the surface of the sample is plotted showing irregularities. Uniform movement of the sample is achieved by using a piezoelectric crystal which generates a voltage on applying a pressure. This helps in plotting out the surface profile.