Model 133 Cesium Ion Source

The presence of cesium atoms in the near surface region of a material under ion bombardment causes copious emission of negative secondary ions. For elements located in group six and to the right of the periodic table, the negative ion yield in the presence of cesium is greater than the positive ion yield in the presence of oxygen, thereby producing better secondary ion mass spectrometric detection limits for those elements. The report introduces principle and structure of model 133 cesium ion source.