A method for producing a silicon substrate, including the steps of providing a silicon substrate having an essentially planar silicon surface, producing a porous silicon surface having a plurality of pores, in particular having macropores and/or mesopores and/or nanopores, applying a filling material that is to be inserted into the silicon, which has a diameter that is less than a diameter of the pores, inserting the filling material into the pores and removing the excess filling material form the silicon surface, if necessary, and tempering the silicon substrate that is furnished with the filling material that has been filled into the pores, at a temperature between ca. 1000° C. and ca. 1400° C., in order to close the generated pores again and to enclose the filling material.