Method for depositing a crystal layer at low temperatures, in particular a photoluminescent iv-iv layer on an iv substrate, and an optoelectronic component having such a layer

Abstract

A method for monolithically depositing a monocrystalline IV-IV layer that glows when excited and that is composed of a plurality of elements of the IV main group, in particular a GeSn or Si—GeSn layer, the IV-IV layer having a dislocation density less than 6 cm, on an IV substrate, in particular a silicon or germanium substrate, including the following steps: providing a hydride of a first IV element (A), such as GeHor SiH; providing a halide of a second IV element (B), such as SnCl; heating the substrate to a substrate temperature that is less than the decomposition temperature of the pure hydride or of a radical formed therefrom and is sufficiently high that atoms of the first element (A) and of the second element (B) are integrated into the surface in crystalline order, wherein the substrate temperature lies, in particular, in a range between 300° C. and 475° C.; producing a carrier gas flow of an inert carrier gas, in particular N, Ar, He, which in particular is not H; transporting the hydride and the halide and decomposition products arising therefrom to the surface at a total pressure of at most 300 mbar; depositing the IV-IV layer, or a layer sequence consisting of IV-IV layers of the same type, having a thickness of at least 200 nm, wherein the deposited layer is, in particular, a SiGeSn layer, with x>0.08 and y≤1.