The invention relates to a manufacturing method of a
metal-coated
ceramic baseplate, which is carried out according to the following steps of: (1) cleanly washing the two surfaces of a
ceramic baseplate; (2) directly
welding metal layers on the upper surface and the lower surface of the
ceramic baseplate, or
brazing the
metal layers on the upper surface and the lower surface of the ceramic baseplate, wherein the outer
peripheral surface of each metal layer and the outer
peripheral surface of the ceramic baseplate have a space d; and (3) brushing a
photoresist along the outer
peripheral surfaces of the two metal
layers, forming at least one thinned and annular step surface at the peripheries of the two metal layers through illumination and
corrosion, and manufacturing the metal-coated ceramic baseplate after washing. In the invention, by photoetching and
thinning the thicknesses of the edges of the metal layers on the metal-coated ceramic baseplate, the
heat stress on the two connecting edges of the step surface can be continuously released, so that not only is the metal-coated ceramic baseplate convenient to manufacture, but also the circulating
heat stress among the ceramic baseplate and the metal layers is effectively reduced, the deformation quantity on the edges of a ceramic basal layer combined with the metal layers is greatly decreased, and the temperature-
cycling reliability and the service of the metal ceramic baseplate can be greatly improved and prolonged.