Silicon electron-beam-induced reduction

SAM is a representative method of the surface analysis aimed at below the micron area. The micro structure of the native oxide film might be able to observe by means of SAM method. However, the severe electron beam-induced damage might be arisen on a silicon oxide film by the high electron current density of primary electron beam (3-7). The silicon oxide is reduced to the elemental silicon due to Joule s heat in an ultra high vacuum analyzer chamber of SAM equipment. The conditions to reduce the reduction of the silicon oxide film due to the electron beam-induced damage have been preferred by the investigations on the compulsive reduction of the silicon oxide film. 

In order to find out the region of reduced electron beam-induced damage, the investigations on the compulsive reduction of the silicon oxide film were performed by using thermally grown silicon oxide film as a reference sample. The electron beam-induced damage were evaluated as a function of LVV spectra intensity ratio for the elemental silicon and the silicon oxide. 

It could be concluded from the above-mentioned experiments on the compulsive reduction of silicon oxide that the conditions of the long irradiation time and the low current is the preferable analytical conditions to reduce the reduction of the oxide film by the electron beam-induced damage. 

The study on the electron beam-induced damage of the silicon oxide film was carried out using thermally grown silicon oxide film as a reference sample. Although the reduction of the oxide film is sensitive to the electron beam density, the long acquisition time reduce the electron beam-induced damage because of the heat dissipation in the thin oxide films. 

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