Novel methods of preparing a metal bonded substrate. A method may include providing a ceramic substrate, the ceramic substrate comprising a ceramic body. The method may include bonding a thick metal sheet to the ceramic substrate, wherein the bonding comprises forming a metal oxide layer by powder deposition on a metal surface, and bringing the ceramic substrate and thick metal sheet together, wherein the metal oxide layer and the thick metal sheet interact to form an interface layer between the thick metal sheet and the ceramic substrate, after the bonding.