Radiation enhanced annealing of radiation damage in Ge

Abstract

Ge (110) single crystals heated to a temperature of 228°C have been bombardment disordered by 40 keV ions at a dose rate of 6 × 10¹¹ ions/cm² sec. The enhanced annealing caused by 40 keV Ge ions at a dose rate of 6 × 10¹¹ions/cm² sec was studied as a function of dose by measuring the secondary electron yield. The depth distribution of damage was determined by the channeling technique using 500 keV He ions. It is shown that enhanced annealing occurs at the inner part of the damage region and proceeds outwards towards the crystal surface. The dose necessary to completely anneal a disordered layer is about 3.0 × 10¹⁵ ions/cm². A model for the annealing process is discussed. The maximum path length of the secondary electrons emitted from Ge during the bombardment with 40 keV Ge ions has been determined to be equal to approximately 40 A.