Principle
Various metal samples are subjected to polychromatic X-rays. The resulting fluorescence radiation is analysed with the aid of a semiconductor detector and a multichannel analyser. The energy of the characteristic X-ray lines and their full widths at half maximum are determined. In addition, the dependence of the full widths at half maximum and the shift of the line centroid as a function of the counting rate are examined.
Tasks
- Calibration of the semiconductor detector with the aid of the characteristic radiation of the molybdenum X-ray tube.
- Recording of the spectra of the fluorescence radiation that is generated by the metal samples.
- Determination of the energy levels and full widths at half maximum of the characteristic Kα lines and their graphical representation.
- Determination and graphical representation of the full widths at half maximum as a function of the counting rate, with the Kα line of zircon used as an example.
- Determination and graphical representation of the shift of the line centroid as a function of the counting rate, with the Kα line of zircon used as an example.
Learning objectives
- Bremsstrahlung
- characteristic X-radiation
- fluorescence radiation
- conduction processes in semiconductors
- doping of semiconductors
- pin-diodes
- resolution and resolving power
- semiconductor energy
- multi-channel analysers