In situ observation of twin formation during the growth of ZnSe single crystals from the vapor phase

Estimation of incorporation energies of Zn-Se and Si-S pairs in different surface steps of ZnSe crystals with a semi-empirical finite-size cluster approach

“…Thus the Zn-Se pair incorporation energy of the {001} surface steps may be essentially higher than that of the {110} surface ledges. Under the assumption that the spreading velocity of a surface step is proportional to the Zn-Se pair incorporation energy, it follows the observed {110} growth form, when the normal growth rates fulfill the condition [1,17].…”

“…As shown in [1] the structure of the steps on the {001} surface is similar to that of the [112] ledge on the (111) face while the steps on the {110} surfaces are identical to the [11 2] ledge on the (111) face. Thus the Zn-Se pair incorporation energy of the {001} surface steps may be essentially higher than that of the {110} surface ledges.…”

“…When single crystals of ZnSe are grown by sublimation at temperatures between 1300 and 1400 K, it is observed that the crystals preferably develop {110} faces. These may be caused by slow-moving surface steps, whose structure agrees with those which travel on the (111) in the [11 2] direction [1].…”

“…An investigation with mass spectrometry reveals that the concentration of SiS 2 species can be neglected [19]. For that reason, as in the previous work [1], it is assumed that Si pairs have occupied the places of the Zn-Se pairs in the fast-moving ledges as consequence of the high density of crossing dangling bonds [1].…”

“…With reference to the previous discussion of dangling bonds on {111}, {110} and {001} surfaces in [1], we have elaborated the incorporation energies of the Zn-Se pairs of these faces using the PM3 model. Usually the (111) face of the sphalerite structure is defined as that plane which ends with a Zn atom.…”