Method of making at least one FET transistor (100a, 100b, 200, 300) including the implementation of at least the following steps: - fabricate at least a first semiconducting portion (114, 202, 302) intended to form a channel of the FET transistor (100a, 100b, 200, 300), - fabricate second semiconducting portions (122, 124, 126, 304, 306) intended to form source and drain regions of the FET transistor (100a, 100b, 200, 300), such that the first semiconducting portion (114, 202, 302) is located between first ends of the second semiconducting portions (122, 124, 126, 304, 306) and such that second ends of the second semiconducting portions (122, 124, 126, 304, 306) opposite the first ends, are in contact with bearing surfaces, and comprising at least one semiconducting material for which the crystalline structure can be modified when a heat treatment is applied to it; - heat treatment generating a modification to the crystalline structure of the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) and creating a strain in the first semiconducting portion (114, 202, 302), Wherein the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) comprises at least one chemical element that can be precipitated during application of the heat treatment, said heat treatment causes precipitation of atoms of said chemical element that can be precipitated, creating interstitial atoms of said chemical element that can be precipitated, and in which, according to a first configuration: - the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) comprises silicon or SiGe, - the chemical element that can be precipitated during application of the heat treatment comprises carbon, and - the fabricated FET transistor (100a, 100b, 200, 300) is of the P type, or in which, according to a second configuration: - the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) comprises germanium, - the chemical element that can be precipitated during application of the heat treatment comprises tin, and - the fabricated FET transistor (100a, 100b, 200, 300) is of the N type. - fabricate at least a first semiconducting portion (114, 202, 302) intended to form a channel of the FET transistor (100a, 100b, 200, 300), - fabricate second semiconducting portions (122, 124, 126, 304, 306) intended to form source and drain regions of the FET transistor (100a, 100b, 200, 300), such that the first semiconducting portion (114, 202, 302) is located between first ends of the second semiconducting portions (122, 124, 126, 304, 306) and such that second ends of the second semiconducting portions (122, 124, 126, 304, 306) opposite the first ends, are in contact with bearing surfaces, and comprising at least one semiconducting material for which the crystalline structure can be modified when a heat treatment is applied to it; - heat treatment generating a modification to the crystalline structure of the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) and creating a strain in the first semiconducting portion (114, 202, 302), and in which, according to a first configuration: - the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) comprises silicon or SiGe, - the chemical element that can be precipitated during application of the heat treatment comprises carbon, and - the fabricated FET transistor (100a, 100b, 200, 300) is of the P type, - the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) comprises silicon or SiGe, - the chemical element that can be precipitated during application of the heat treatment comprises carbon, and - the fabricated FET transistor (100a, 100b, 200, 300) is of the P type, or in which, according to a second configuration: - the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) comprises germanium, - the chemical element that can be precipitated during application of the heat treatment comprises tin, and - the fabricated FET transistor (100a, 100b, 200, 300) is of the N type. - the semiconducting material of the second semiconducting portions (122, 124, 126, 304, 306) comprises germanium, - the chemical element that can be precipitated during application of the heat treatment comprises tin, and - the fabricated FET transistor (100a, 100b, 200, 300) is of the N type.