Wurtzite Structure Semiconductors

Abstract

The wurtzite structure II–VI semiconductors are closely related to the II–VI zinc-blendes. In analogy with the diamond and zinc-blende structures, the wurtzite structure can be constructed by considering two interpenetrating lattices. However, in this case they are hexagonal close packed lattices. The nearest neighbors and next nearest neighbors are the same in the ideal wurtzite and zinc-blende structures. For the ideal wurtzite case, the lattice parameters are c/a = 2√6/3 = 1.633, and u = 3/8 [9.1]. When the nearest neighbor distance is the same in the wurtzite and zinc-blende structures, the lattice constants are related by a z = √2a w. For wurtzite, there are four atoms per unit cell in contrast to two for zinc-blende. Since the volume per atom is the same, a given volume of reciprocal space for wurtzite contains approximately twice as many reciprocal lattice points. The lattice constants for several wurtzite structure semiconductors are given in Table 9.1.