A method for forming a pre-processed semiconducting thermoelectric conversion material for metallization, interconnection and bonding, wherein the method comprises the following process steps in successive order: - employing at least one element of a n-type or p-type doped semiconducting thermoelectric conversion material having a first and second surface on opposite sides, - placing the at least one element of semiconducting thermoelectric conversion material into a deposition chamber, and then: i) depositing a first adhesion layer of a first metal directly onto the first and the second surface of the element of the semiconducting thermoelectric conversion material, ii) depositing a diffusion barrier layer of a non-metallic compound of a second metal directly onto the first adhesion layer on the first and second surface of the semiconducting thermoelectric conversion material element, iii) depositing a second adhesion layer of a third metal directly onto the diffusion barrier layer of the non-metallic compound of the second metal on the first and second surface of the element of the semiconducting thermoelectric conversion material, wherein - the deposition chamber is either a chemical vapour deposition chamber, a physical vapour deposition chamber, or an atomic deposition chamber, and the deposition of the different layers of steps i) to iii) is obtained by feeding pre-cursor gases with varying chemical composition into the deposition chamber, - the non-metallic compound of the second metal is either a nitride or an oxide of the second metal, - depositing a first bonding layer of a metal A directly onto the second adhesion layer on the first and second surface of element of the semiconducting thermoelectric conversion material, and - depositing a second bonding layer of a metal B directly onto the first bonding layer the on the first and second surface of the element of the semiconducting thermoelectric conversion material, wherein - the melting point of metal A is higher than metal B and metal B is chemically reactive towards metal A at their common interface when subject to heating above the melting point of metal B forming an intermetallic compound by solid-liquid interdiffusion. - employing at least one element of a n-type or p-type doped semiconducting thermoelectric conversion material having a first and second surface on opposite sides, - placing the at least one element of semiconducting thermoelectric conversion material into a deposition chamber, and then: i) depositing a first adhesion layer of a first metal directly onto the first and the second surface of the element of the semiconducting thermoelectric conversion material, ii) depositing a diffusion barrier layer of a non-metallic compound of a second metal directly onto the first adhesion layer on the first and second surface of the semiconducting thermoelectric conversion material element, iii) depositing a second adhesion layer of a third metal directly onto the diffusion barrier layer of the non-metallic compound of the second metal on the first and second surface of the element of the semiconducting thermoelectric conversion material, wherein - the deposition chamber is either a chemical vapour deposition chamber, a physical vapour deposition chamber, or an atomic deposition chamber, and the deposition of the different layers of steps i) to iii) is obtained by feeding pre-cursor gases with varying chemical composition into the deposition chamber, - the non-metallic compound of the second metal is either a nitride or an oxide of the second metal, i) depositing a first adhesion layer of a first metal directly onto the first and the second surface of the element of the semiconducting thermoelectric conversion material, ii) depositing a diffusion barrier layer of a non-metallic compound of a second metal directly onto the first adhesion layer on the first and second surface of the semiconducting thermoelectric conversion material element, iii) depositing a second adhesion layer of a third metal directly onto the diffusion barrier layer of the non-metallic compound of the second metal on the first and second surface of the element of the semiconducting thermoelectric conversion material, - the deposition chamber is either a chemical vapour deposition chamber, a physical vapour deposition chamber, or an atomic deposition chamber, and the deposition of the different layers of steps i) to iii) is obtained by feeding pre-cursor gases with varying chemical composition into the deposition chamber, - the non-metallic compound of the second metal is either a nitride or an oxide of the second metal, - depositing a first bonding layer of a metal A directly onto the second adhesion layer on the first and second surface of element of the semiconducting thermoelectric conversion material, and - depositing a second bonding layer of a metal B directly onto the first bonding layer the on the first and second surface of the element of the semiconducting thermoelectric conversion material, wherein - the melting point of metal A is higher than metal B and metal B is chemically reactive towards metal A at their common interface when subject to heating above the melting point of metal B forming an intermetallic compound by solid-liquid interdiffusion.