Metal-coated ceramic baseplate and manufacturing method thereof

Abstract

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.

Description

technical field [0001] The invention relates to a metal-clad ceramic substrate and a manufacturing method thereof, belonging to the technical field of semiconductors. technical background [0002] Metal-clad substrates are mainly used in the power electronics industry. In a power module, several power semiconductor chips, such as MOSFET or IGBT chips, and diode chips are integrated and soldered or pasted on the metallized surface of the metal-ceramic substrate. On the other hand, the role of the ceramic substrate is to provide electrical insulation relative to the module bottom plate while ensuring good thermal conductivity. Usually, power electronic devices need to work in a temperature cycle environment from -40°C to 125°C. Since the thermal expansion coefficients of the ceramic substrate and the metal layer do not match, cyclic thermal stress will be generated between the ceramic substrate and the metal layer under temperature cycle conditions , especially the thermal st...

AI Technical Summary

Problems solved by technology

As a result, power electronic devices packaged with untreated aluminum oxide copper-clad substrates cannot be used in occasions with high life expectancy, such as high-power inverters in automotive electronics, solar energy, and wind power generation.

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