On Independence of the Thermal-Spike Temperature in Pure Metals of the Implanted Ion Energy and Atomic Mass

Abstract

The optical emission spectra of pure metals Fe, Zr, Ta and W are measured during their irradiation with Ar+, Kr+ and Xe+ ions (5, 10, 15 and 20 keV). It is found out that the energy and ion type in this energy range do not appreciably affect the thermal emission spectral profile of these targets and hence do not influence the thermal spike temperature formed in the zones of passing dense cascades of atomic displacements. It is shown that a constant temperature regime of the thermal peaks (T = const) is fulfilled in the case where the average radius R of the cascade region is proportional to the square root of the incident ion energy$$ \left(R\sim \sqrt{E}\right) $$, and the major part of the thermal energy is released at the cascade periphery of a fixed length. As a result, the energy per atom of the medium, released in this region, does not vary with the ion energy and cascade radius. It is also shown that the thermal spike temperature for all ion types essentially depends on the target material.