EFFECT OF TEMPERATURE ON THE PENETRATION OF HEAVY keV IONS IN MONOCRYSTALLINE SOLIDS: II. VARIOUS IONS IN GOLD, ALUMINIUM, AND TUNGSTEN

Abstract

The influence of atomic thermal motion on the penetration of various heavy keV ions incident along low index channels of single crystals of gold, aluminium, and tungsten has been investigated over the temperature range 15–295 °K. In general, in gold and aluminium the effect of thermal vibrations on the slowing down of the bombarding ions was quite pronounced, whereas a less marked effect was observed in tungsten. The magnitude of the temperature effect was dependent upon the type of bombarding ion and it is suggested that this is due, to a large extent, to the difference in the relative importance of electronic to nuclear stopping along the channel in the various systems. Thermal effects on the stability of the channeled trajectories are also believed to be important. The penetration of the channeled ions was observed to decrease exponentially with increasing temperature. In addition, the magnitude of the temperature effect was found to be relatively insensitive to the bombardment direction for incidence along the more open channels.