Phase diagram of Ge:(C, Sn)

We present the self-assembling conditions of 1C4Sn tetrahedral nanoclusters with carbon atoms in their centers in Ge:(C, Sn) in the wide temperature range as a function of the impurity contents and temperature. These conditions are the phase diagram of Ge:(C, Sn) since nanocluster occurrence and completion of self-assembling when all carbon atoms are in nanoclusters are results of the continuous phase transitions. The significant decrease of the strain energy after formation of nanoclusters is a cause of self-assembling. It is shown that the nanocluster occurrence temperature depends only on the Sn content. The impurity content conditions when all carbon atoms are in 1C4Sn nanoclusters are obtained for the temperatures up to 855 ∘C.