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

We have investigated the low temperature epitaxy of high Sn content GeSn alloys in a 200 mm industrial Reduced Pressure - Chemical Vapor Deposition tool from Applied Materials. Gaseous digermane (Ge2H6) and liquid tin tetrachloride (SnCl4) were used as the Ge and Sn precursors, respectively. The impact of temperature (in the 300–350 °C range), Ge2H6 and SnCl4 mass-flows on the GeSn growth kinetics at 100 Torr has been thoroughly explored. Be it at 300 °C or 325 °C, a linear GeSn growth rate increase together with a sub-linear Sn concentration increase occurred as the SnCl4 mass-flow increased, irrespective of the Ge2H6 mass flow (fixed or varying). The Sn atoms seemed to catalyze H desorption from the surface, resulting in higher GeSn growth rates for high SnCl4 mass-flows (in the 4–21 nm min?1 range). The evolution of the Sn content x with the [formula ommited] mass-flow ratio was fitted by [formula ommited]=n·[formula ommited], with n = 0.25 (325 °C) and 0.60 (300 °C). We have otherwise studied the impact of temperature, in the 300–350 °C range, on the GeSn growth kinetics. The GeSn growth rate exponentially increased with the temperature, from 15 up to 32 nm min?1. The associated activation energy was low, i.e. Ea = 10 kcal mol?1. Meanwhile, the Sn content decreased linearly as the growth temperature increased, from 15% at 300 °C down to 6% at 350 °C. © 2017 Elsevier B.V.

A1. Atomic force microscopy, A1. X-ray diffraction, A3. Chemical vapor deposition processes, B1. Alloys, B2. Semiconducting materials

Activation energy, Atomic force microscopy, Chemical vapor deposition, Deposition, Germanium, Growth kinetics, Growth rate, Kinetics, Mass transfer, Temperature, Tin, Tin alloys, Vapor deposition, X ray diffraction, Applied materials, Chemical vapor deposition process, Impact of temperatures, Low temperature epitaxies, Mass flow ratios, Reduced pressure chemical vapor deposition, Semiconducting materials, Sn concentration, Chlorine compounds