Xhyphen;ray measurements of ion mixing in amorphous Si/Ge artificial multilayers

摘要

Amorphous Si/Ge artificial multilayers with a repeat length around 60 Aring; have been partially mixed with 1.5hyphen;MeV Ar+ions at temperatures in the range 77ndash;673 K. The diffusive component of the square of the mixing length, obtained by subtracting out the ballistic contribution, does not depend on the dose rate at a given dose, and shows an Arrheniushyphen;type temperature dependence with activation enthalpies between 0.13 and 0.22 eV. Possible mechanisms for migration and annihilation processes of defects are discussed to understand these low activation enthalpies.