| 摘要 |
The invention relates to a method for producing III-V-, IV- IV- or II-VI- compound semiconductor crystals. The method starts with the provision of a substrate having optionally one crystal layer (buffer layer). This is followed by the provision of a gas phase which has at least two reactants of elements for the compound semiconductor (II, III, IV, V, VI), the reactants being gaseous at a reaction temperature in the crystal growth reactor and being capable of reacting together under the selected reactor conditions. The ratio of the concentrations of two of the reactants is adjusted such that the compound semiconductor crystal can crystallize from the gas phase, a concentration being chosen that is sufficiently high to facilitate crystal formation and the activity of the III-, IV- or II-compound being reduced in the gas phase by the addition or adjustment of reducing agent and co-reactant, such that the growth rate of the crystal is lower compared to a state without the co-reactant. The compound semiconductor crystal is deposited on a surface of the substrate, whilst a liquid phase can form on the growing crystal. In addition, auxiliary substances can be added which can also be contained in the liquid phase but which are only incorporated in negligible amounts into the compound semiconductor crystal. This allows 3D and 2D growth modes to be controlled selectively. The addition of auxiliary substances and the presence of a liquid phase promote these measures. The product is a single crystal of a III-V-, IV-IV- or II-VI-compound semiconductor crystal, which contains lower concentrations of inclusions or precipitates compared to conventional compound semiconductor crystals and which nevertheless has no or only a negligible curvature. |
