Abstract: A method for forming SiGe-based regions with different Ge concentrations is provided. After defining the regions 1, 2 on a SOI substrate, a grating of masking patterns is formed on at least one region 2. After the epitaxial growth of a Ge-based layer in each of the regions, a first vertical diffusion is carried out. A second horizontal diffusion is then carried out such that the Ge diffuses beneath the masking patterns of the region 2. Thus, the region 2 has a Ge concentration that is lower than the Ge concentration of the region 1.

Abstract: A method for manufacturing a pFET transistor, the method for manufacturing the transistor including providing a base structure comprising a silicon channel and a gate structure, the gate structure surrounding the channel leaving two flanks of the channel free; growing a first layer made from silicon-germanium alloy on the flanks of the channel; enriching the channel with germanium atoms from the first layer; and forming a drain region and a source region on either side of the channel.

Abstract: A method for forming crystalline SiC-based regions on either side of an N-type transistor channel, including: providing a substrate including a silicon-based layer having a thickness e, forming at least one masking pattern on the silicon-based layer, with the at least one masking pattern having openings, with the openings corresponding to implantation regions of the silicon-based layer, amorphising the silicon-based layer through the openings of the at least one masking pattern, in the implantation regions, to a depth d strictly less than the thickness e, so as to form amorphised implantation regions in the silicon-based layer, implanting carbon into amorphous implantation regions, performing thermal recrystallisation annealing to turn the amorphised implantation regions into crystalline SiC-based regions, the method including: after forming the crystalline SiC-based regions, forming a transistor gate on the silicon-based layer, directly at the edge of the crystalline SiC-based regions.

Abstract: A method for forming SiGe-based regions with different Ge concentrations is provided. After defining the regions 1, 2 on a SOI substrate, a grating of masking patterns is formed on at least one region 2. After the epitaxial growth of a Ge-based layer in each of the regions, a first vertical diffusion is carried out. A second horizontal diffusion is then carried out such that the Ge diffuses beneath the masking patterns of the region 2. Thus, the region 2 has a Ge concentration that is lower than the Ge concentration of the region 1.

Abstract: A semiconductor structure can include a substrate and a substrate layer. The substrate can be formed of silicon and the substrate layer can be formed of silicon germanium. Above the substrate and under the substrate layer there can be provided a multilayer substructure. The multilayer substructure can include a first layer and a second layer. The first layer can be formed of a first material and the second layer can be formed of second material. A method can include forming a multilayer substructure on a substrate, annealing the multilayer substructure, and forming a substrate layer on the multilayer substructure.