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Energy efficiency being the driver of future information technology leads to the rise of new architecture and materials entering main stream Silicon technology.Here the aspect of new materials is discussed,putting special emphasis on the opportunities and challenges offered by GeSn,Ⅲ/Ⅴ nanowires and topological insulator materials.The deposition and monolithic integration of these materials on Si substrates require specialized epitaxial techniques.Successful deposition of GeSn alloys with Sn concentration up to 15%is achieved by reactive gas source epitaxy.Optically pumped laser manufactured from GeSn films proof the potential to integrate group Ⅳ optoelectronics into CMOS circuitry [1].Various laser using Fabry-Perot as well as microdisc geometry have been fabricated using GeSn films with Sn concentration ranging from 8.5 to 14%.Accordingly the emission wavelength shifts from 2 to 2.6 μm.GeSn with a Sn concentration >8%is a direct band gap semiconductor,harboring electrons with a very low effective mass,comparable to InAs or InSb,in the conduction point minimum at the Γ-point.Thus GeSn offers the possibility to integrate optical as well as high speed electronic devices in one platform and thus might be an alternative to the approach to integrate Ⅲ/Ⅴ compounds to Si.A promising path for monolithic integration of Ⅲ/Ⅴ on Si is the growth of Ⅲ/Ⅴ nanowires.Catalyst free growth of radial and axial nanowire heterostructures is successfully implemented to MBE growth on Si [2].Here,In rich group Ⅲ-As and-Sb alloys providing high mobilities and high g-factors are potential candidates for nanoelectronic and spintronic applications as well as to study quantum phenomena in charge based devices.To this end,new materials,so called layered or 2-dimensional materials,are a subsequent step ahead to study quantum phenomena and innovative devices.Van-der-Waals epitaxy is a potential method to build almost arbitrary stacks of layered films.Here we discuss the deposition of Bi2Te3/Sb2Te3 topological insulator heterostructures [3] on planar Si as well as on patterned Si substrates.