Method of joining metal-ceramic substrates to metal bodies
AssigneeIXYS Semiconductor GmbH
InventorHeiko Knoll
Life of this patent
Estimating the term…
Abstract
A method of joining a metal-ceramic substrate having metallization on at least one side to a metal body by using metal alloy is disclosed. The metal body has a thickness of less than 1.0 mm and the metal alloy contains aluminum and has a liquidus temperature of greater than 450° C. The resulting metal-ceramic module provides a strong bond between the metal body and the ceramic substrate. The resulting module is useful as a circuit carrier in electronic appliances, with the metal body preferably functioning as a cooling body.
Claims21
A method of joining a metal-ceramic substrate to a metal body using a metal alloy, where the metal-ceramic substrate has metallization on at least one side, the method comprising:
- providing the metal body with a thickness of less than 1 mm;
- placing a metal alloy which contains aluminum and has a liquidus temperature of greater than 450° C. between the metal-ceramic substrate and the metal body to form an assembly, wherein the metal-ceramic substrate is adapted to have a semiconductor component disposed on at least one metalized side of the metal-ceramic substrate, and wherein the metal-ceramic substrate includes a ceramic substrate and no more than two metal layers;
- and
- heating the assembly to a temperature of greater than 450° C. such that the at least one metalized side of the metal-ceramic substrate contacts an inert gas atmosphere during heating.
A module comprising:
- (a) arranging a metal alloy between a metal-ceramic substrate and a metal body having a thickness of less than 1 mm, wherein an upper surface of the metal alloy contacts a lower surface of the metal-ceramic substrate, wherein a lower surface of the metal alloy contacts an upper surface of the metal body, wherein the metal alloy comprises aluminum, wherein the metal alloy has a liquidus temperature of at least 450° C., wherein the metal-ceramic substrate is adapted to have a semiconductor component disposed on at least one metalized side of the metal-ceramic substrate, and wherein the metal-ceramic substrate includes a ceramic substrate and no more than two metal layers;
- and
- (b) bounding the metal-ceramic substrate to the metal body such that a peel force for separating the metal-ceramic substrate from the metal body exceeds 3 N/mm, and such that the at least one metalized side of the metal-ceramic substrate contacts an inert gas atmosphere during bonding.
The method of comprising:
- (a) placing an assembly onto a conveyor belt of a furnace having a plurality of heating zones, wherein the assembly comprises a substrate, a first metal layer, and a second metal layer having a thickness of less than 1 mm, wherein the substrate is disposed above the first metal layer such that a lower surface of the substrate contacts an upper surface of the first metal layer, wherein the first metal layer is disposed above the second metal layer such that a lower surface of the first metal layer contacts an upper surface of the second metal layer, wherein the first metal layer comprises aluminum and has a liquidus temperature of at least 450° C., wherein at least one metalized side of the substrate is adapted to receive a semiconductor component, and wherein the substrate includes a ceramic substrate and no more than two metal layers;
- (b) heating the assembly through the plurality of heating zones of the furnace such that the at least one metalized side of the substrate contacts an inert gas atmosphere during heating, wherein the assembly is heated from between 580° C. to 650° C.;
- and
- (c) cooling the assembly to room temperature.
Dependencies are inferred from the claim text.