Cathode shape dependence of gas ionization chamber on electron collection in - telescope ERDA

Harayama, Isao  ; Hirose, Yasushi*; Sekiba, Daiichiro*

- telescope elastic recoil detection analysis (ERDA) is a helpful ion beam analysis (IBA) technique for the absolute quantification of multiple light elements in thin films. We have developed a compact - telescope ERDA system to estimate a composition ratio of oxygen and nitrogen in metal oxynitride thin films. Our - telescope ERDA system employs a gas ionization chamber (GIC), which consisted of a U-shaped cathode, while a planar shaped cathode is widely utilized for GICs. The shape of U-shaped cathode is useful to downsize the GIC. The difference of performance between the U-shaped and planar shaped cathodes, however, has not been studied well, yet. In this study, we quantitatively evaluated the influence using the U-shaped cathode on - telescope ERDA. In order to compare the performance of the U-shaped and planar shaped cathode, we measured SrTiO bulk samples as a standard with them. There is no significant difference between the two cathodes from the viewpoint of O recoil yields. These results show that the U-shaped cathode can also be used safely for - telescope ERDA, and that GICs have a flexibility in the electrode shape, which is useful to make GICs more compact.