Mobile ion effects in low-temperature silicon oxides

Publisher Website
Google Scholar
Abstract
Mobile ions in oxides formed on silicon by low-temperature processes have been studied using a combination of bias-temperature stress and triangular voltage sweep experiments. It is found that these oxides contain intrinsically low concentrations of mobile ions (<1010 cm−2) and that the ionic instabilities which are seen are due to alkali metal ions rather than other contaminants or the inherent water and hydrogen. Mobile sodium behaves slightly differently in low-temperature oxides compared with conventional thermal oxides, and can be gettered and passivated using a low-temperature process. It is shown that sodium ions are trapped by polycrystalline silicon during plasma hydrogenation, and that atomic hydrogen is involved in this process. The trapped ions are released back into the oxide during subsequent bias-temperature stressing.

This publication has 3 references indexed in Scilit: