GROWTH-MECHANISM OF II-VI COMPOUND SEMICONDUCTORS BY MOLECULAR-BEAM EPITAXY

The basic model of MBE growth of ZnMgSSe at 275 degrees C is considere d. The net flux intensity is expressed by the product of the flux inte nsity and the maximum sticking coefficient for the cracked or heated b eam flux. The surface of the crystal is divided into a surface covered with group II elements (surface II) and a surface covered with group VI elements (surface VI) and the adatom density is almost the same at surface II and surface VI. The desorption of these adatoms is expresse d by considering the effect of cluster such as S-2 and Se-2. The desor ption from the surface is disregarded because the growth temperature i s low. The experimental composition and the growth rate of ZnMgSSe agr ees with the values calculated using this theory and the tendency of t hese properties when the c(2 x 2) pattern is observed is different fro m the tendency when (2 x 1) is observed.