Method for structuring metal-ceramic substrates, and structured metal ceramic substrate

A method for structuring metal-ceramic substrates, comprising the steps of:

• a) providing a first metal-ceramic substrate and a second metal-ceramic substrate, each comprising
• a ceramic layer,
• a metal layer, and
• a bonding layer located between the ceramic layer and the metal layer, wherein the bonding layer comprises (i) a metal having a melting point of at least 700° C. and (ii) an active metal,
• b) providing an etching solution 1 that is capable of removing the metal from the metal layer and at least partly removing the metal having a melting point of at least 700° C. from the bonding layer,
• c) providing an etching solution 2 that is capable of removing the active metal from the bonding layer,
• d) masking regions on the metal layer of the first metal-ceramic substrate and on the metal layer of the second metal-ceramic substrate that are not intended to be removed,
• e) contacting the first metal-ceramic substrate and the second metal-ceramic substrate with the etching solution 1, and
• f) contacting the first metal-ceramic substrate and the second metal-ceramic substrate with the etching solution 2, wherein the first metal-ceramic substrate and the second metal-ceramic substrate are positioned such that an orthogonal projection of the first metal-ceramic substrate onto a projection plane parallel to the metal layer of the first metal-ceramic substrate shades no more than 60% of the metal layer of the second metal-ceramic substrate.