Abstract: A method of fabricating a polycrystalline silicon carbide carrier substrate involves growing an initial polycrystalline silicon carbide substrate on a seed of graphite or of silicon-carbide. A stiffening carbon film is then formed on a front face of the initial substrate. The initial substrate has, in the plane of its front face, a first average silicon carbide grain size. The seed is then removed, so as to free the back face of the initial substrate, which has, in the plane of its back face, a second average silicon carbide grain size, which is smaller than the first average size. The back face of the initial substrate is then thinned to a thickness for which the initial substrate has, in the plane of its thinned back face, a third average grain size equal to the first average grain size to within ±30%.

Abstract: A method of fabricating a polycrystalline silicon carbide carrier substrate involves growing an initial polycrystalline silicon carbide substrate on a seed of graphite or of silicon-carbide. A stiffening carbon film is then formed on a front face of the initial substrate. The initial substrate has, in the plane of its front face, a first average silicon carbide grain size. The seed is then removed, so as to free the back face of the initial substrate, which has, in the plane of its back face, a second average silicon carbide grain size, which is smaller than the first average size. The back face of the initial substrate is then thinned to a thickness for which the initial substrate has, in the plane of its thinned back face, a third average grain size equal to the first average grain size to within ±30%.