Method for bonding semiconductor substrates and devices obtained thereof

A method for thermo-compressing bonding a first substrate to a second substrate, the method comprising:

• providing a first semiconductor substrate and a second semiconductor substrate, wherein the first semiconductor substrate and the second semiconductor substrate each comprise at least one metal contact structure on a surface thereof;
• planarizing surfaces of the at least one metal contact structures;
• positioning the second semiconductor substrate in a proximity of the first semiconductor substrate, thereby aligning the at least one metal contact structure of the first semiconductor substrate with the at least one metal contact structure of the second semiconductor substrate, and bringing in contact the at least one metal contact structure of the first semiconductor substrate with the at least one metal contact structure of the second semiconductor substrate;
• mechanically scrubbing the surface of the at least one metal contact structure of the first semiconductor substrate against the surface of the at least one metal contact structure of the second semiconductor substrate, thereby cleaning the surfaces;
• bonding the first semiconductor substrate to the second semiconductor substrate using a thermal compression bonding, thereby forming a semiconductor substrate stack;
• and
• thermally annealing the semiconductor substrate stack, thereby creating an interface diffusion between the at least one metal contact structure of the first semiconductor substrate and the at least one metal contact structure of the second semiconductor substrate.