inexpensive characterization of instrument performance
The NiOx Test Specimen has been developed for advanced analytical TEM's equipped with X-Ray Micro Analysis Systems (EDX) and/or Electron Energy Loss Spectrometers (EELS) to characterize instrument performance. It consists of a 55nm layer of NiOx on a 25nm carbon support film on a 200 mesh Mo TEM grid. The NiOx Test Specimen is valuable in at least three ways:
The test specimen provides an Mo signal to measure stray X-rays and electrons present in the TEM column. The NiOx film contains a known amount of a light element (oxygen) and is used for evaluation the EDX detector response to low energy X-rays. In EELS, the oxygen and nickel ionization edges allow energy-axis calibration and elemental-ratio measurements to be performed. It is possible to make a direct comparison of elemental analyses obtained by EDX and EELS for a TEM equipped with both systems.
Since the nickel oxide film is a fine-grained polycrystal, it is well suited to the calibration of TEM camera length and the correction of intermediate-lens astigmatism.
Each specimen is packaged in an aluminum storage container #650-10 with instructions for the measurement of camera length, evaluating the amount of stray radiation in the TEM column and its predominant character (X-rays or electrons), for estimating the collection solid angle of the EDX detector and for determining the extent of ice or hydrocarbon contamination on the detector.