Univ. Grenoble Alpes, Grenoble, France, CEA, LETI, Minatec Campus, Grenoble, France, CEA-INAC, Univ. Grenoble Alpes, Grenoble, France

We have grown various thicknesses of GeSn layers in a 200 mm industrial Reduced Pressure – Chemical Vapor Deposition cluster tool using digermane (Ge2H6) and tin tetrachloride (SnCl4). The growth pressure (100 Torr) and the F(Ge2H6)/F(SnCl4) mass-flow ratio were kept constant, and incorporation of tin in the range of 10–15% was achieved with a reduction in temperature: 325 °C for 10% to 301 °C for 15% of Sn. The layers were grown on 2.5 µm thick Ge Strain Relaxed Buffers, themselves on Si(0 0 1) substrates. We used X-ray Diffraction, Atomic Force Microscopy, Raman spectroscopy and Scanning Electron Microscopy to measure the Sn concentration, the strain state, the surface roughness and thickness as a function of growth duration. A dramatic degradation of the film was seen when the Sn concentration and layer thickness were too high resulting in rough/milky surfaces and significant Sn segregation. © 2017 Elsevier B.V.

A1. Atomic force microscopy, A1. High resolution X-ray diffraction, A1. Segregation, A3. Chemical vapor deposition processes, B2. Alloys, B2. Semiconducting germanium

Atomic force microscopy, Chemical vapor deposition, Deposition, Germanium, Scanning electron microscopy, Semiconducting germanium, Surface roughness, Vapor deposition, X ray diffraction, Chemical vapor deposition process, Growth pressure, High resolution X ray diffraction, Layer thickness, Mass flow ratios, Reduced pressure, Sn concentration, Strain relaxed buffers, Tin