Ceramic-aluminum assembly with bonding trenches

Abstract

A method of joining is provided. the method includes preparing a first member, preparing a second member, and forming at least one trench in at least one of the first member and the second member. The method further includes placing a strip of solid aluminum material between the first member and the second member across the trench, bringing the first member and the second member together to contact the solid aluminum material and to form an assembly, and applying a force and heat to the assembly above a melting point of the solid aluminum material such that the solid aluminum material flows into the trench. Additionally, the method further includes applying additional heat to the assembly at or above a wetting temperature of the member in which the trench is formed to bond the first member to the second member along adjacent faces and cooling the assembly.

What is claimed is: 
     
         1 . A method of joining comprising:
 preparing a first member;   preparing a second member;   forming at least one trench in at least one of the first member and the second member;   placing a strip of solid aluminum material between the first member and the second member across the trench;   bringing the first member and the second member together to contact the solid aluminum material and to form an assembly;   applying a force and heat to the assembly above a melting point of the solid aluminum material such that the solid aluminum material flows into the trench;   applying additional heat to the assembly at or above a wetting temperature of the member in which the trench is formed to bond the first member to the second member along adjacent faces; and   cooling the assembly,   wherein a spacing between the first member and the second member along the adjacent faces is less than 5 μm.   
     
     
         2 . The method according to  claim 1 , wherein preparing the first and second member comprises creating a surface roughness of the adjacent faces of the first and second members between 5 μm and 100 nanometers. 
     
     
         3 . The method according to  claim 1 , wherein the first member and the second member are selected from the group consisting of aluminum nitride (AlN), alumina, zirconia, and silicon carbide (SiC). 
     
     
         4 . The method according to  claim 1 , wherein each of the first member and the second member are each aluminum nitride (AlN). 
     
     
         5 . The method according to  claim 4 , wherein the wetting temperature is above 850° C. 
     
     
         6 . The method according to  claim 1 , wherein a purity of the strip of solid aluminum material is greater than or equal to about 97% and the assembly is heated to a temperature above about 800° C., and the force applied to the assembly is between about 0.1 MPa to 6.5 MPa. 
     
     
         7 . The method according to  claim 1 , wherein the applying additional heat to the assembly comprises heating the assembly to 1100° C. under a vacuum condition of approximately 10 −3  Torr. 
     
     
         8 . The method according to  claim 1 , wherein applying additional heat to the assembly comprises heating the assembly to 800° C. under a vacuum condition of approximately 10 −6  Torr. 
     
     
         9 . The method according to  claim 1 , wherein the solid aluminum material is aluminum foil. 
     
     
         10 . The method according to  claim 1 , wherein the solid aluminum material is applied by a physical vapor deposition (PVD) process. 
     
     
         11 . The method according to  claim 1 , wherein at least one trench is formed with a depth and a width, and the width of the trench is between 5 and 20 times the depth of the trench. 
     
     
         12 . The method according to  claim 1 , wherein each of the first member and the second member are each a flat plate. 
     
     
         13 . The method according to  claim 1 , wherein the first member is a flat plate and the second member is a hollow shaft. 
     
     
         14 . The method according to  claim 1  further comprising forming a plurality of trenches that are spaced a distance apart less than 2 mm. 
     
     
         15 . A method of joining comprising:
 preparing a first member;   preparing a second member;   forming a plurality of trenches spaced a distance apart less than 2 mm in at least one of the first member and the second member,   placing a strip of solid aluminum material between the first member and the second member across the trench;   bringing the first member and the second member together to contact the solid aluminum material and to form an assembly;   applying a force and heat to the assembly above a melting point of the solid aluminum material such that the solid aluminum material flows into the trench;   applying additional heat to the assembly at or above a wetting temperature of the member in which the trench is formed to bond the first member to the second member along adjacent faces; and   cooling the assembly,   wherein a spacing between the first member and the second member along the adjacent faces is less than 5 μm.   
     
     
         16 . The method according to  claim 15 , wherein preparing the first and second member comprises creating a surface roughness of the adjacent faces of the first and second members between 5 μm and 100 nanometers. 
     
     
         17 . The method according to  claim 15 , wherein the first member and the second member are selected from the group consisting of aluminum nitride (AlN), alumina, zirconia, and silicon carbide (SiC). 
     
     
         18 . The method according to  claim 15 , wherein each of the first member and the second member are each aluminum nitride (AlN). 
     
     
         19 . The method according to  claim 15 , wherein the solid aluminum material is aluminum foil. 
     
     
         20 . The method according to  claim 15 , wherein the solid aluminum material is applied by a physical vapor deposition (PVD) process.