The mobility of Na+, Li+, and K+ ions in thermally grown SiO2 films

Na+, Li+, and K+ ions have been implanted in thermally grown oxides (Tox =1000 °C) of metal-oxide-silicon structures. The mobilities of the Na+ and Li+ ions have been determined by means of the isothermal transient ionic current method in the temperature range 100–300 °C. The K+ mobility has been obtained by means of triangular voltage sweep measurements in the range 350–450 °C. The results show that the Na+ and the Li+ mobilities are not significantly different. The activation energies of the three measured mobilities are shown to agree with a quantitative model which has been developed by Anderson and Stuart [J. Am. Ceram. Soc. 37, 573 (1954)].