Method of forming an interconnect joint

Abstract

A method of forming an interconnect joint includes providing a first metal layer ( 210, 310 ), providing a film ( 220, 320 ) including metal particles ( 221, 321 ) and organic molecules ( 222, 322 ), placing the film over the first metal layer, placing a second metal layer ( 230, 330 ) over the film, and sintering the metal particles such that the organic molecules degrade and the first metal layer and the second metal layer are joined together.

1 . A method of forming an interconnect joint, the method comprising:
 providing a first metal layer;   providing a film comprising metal particles and organic molecules;   placing the film over the first metal layer;   placing a second metal layer over the film; and   sintering the metal particles such that the organic molecules degrade and the first metal layer and the second metal layer are joined together.   
   
   
       2 . The method of  claim 1  wherein:
 placing the film comprises:
 immersion-coating the metal particles onto the first metal layer; and 
 immersion-coating the organic molecules onto the metal particles. 
   
   
   
       3 . The method of  claim 1  wherein:
 placing the film comprises:
 providing a solvent comprising metal particles coated with organic molecules; and 
 immersion-coating the metal particles coated with organic molecules onto the first metal layer. 
   
   
   
       4 . The method of  claim 1  wherein:
 placing the film comprises spin coating the film onto the first metal layer.   
   
   
       5 . The method of  claim 1  wherein:
 placing the film comprises printing the film onto the first metal layer.   
   
   
       6 . The method of  claim 1  wherein:
 providing the film comprises:
 providing the metal particles to be particles of one of gold, silver, platinum, palladium, and copper; and 
 providing the organic molecules to be organic molecules comprising a first group with an affinity for metals and a second group with an affinity for metals. 
   
   
   
       7 . The method of  claim 6  wherein:
 the first group and the second group are one of thiol, amine, hydroxyl, and carboxyl.   
   
   
       8 . The method of  claim 1  wherein:
 sintering the metal particles comprises exposing the first metal layer, the film, and the second metal layer to electromagnetic radiation.   
   
   
       9 . The method of  claim 1  wherein:
 sintering the metal particles comprises heating the first metal layer, the film, and the second metal layer to a temperature between approximately 100 degrees Celsius and approximately 180 degrees Celsius.   
   
   
       10 . The method of  claim 1  further comprising:
 treating a surface of the first metal layer before placing the film over the first metal layer.   
   
   
       11 . A method of forming an interconnect joint, the method comprising:
 providing a first metal layer;   dispersing a plurality of metal particles in a first solvent;   performing a first immersing step in which the first metal layer is immersed in the first solvent such that the first metal layer is coated with a layer of the metal particles;   dispersing a plurality of organic molecules in a second solvent;   performing a second immersing step in which the first metal layer is immersed in the second solvent such that the layer of metal particles is coated with a layer of organic molecules;   placing a second metal layer over the layer of organic molecules; and   sintering the metal particles such that the organic molecules degrade and the first metal layer and the second metal layer are joined together.   
   
   
       12 . The method of  claim 11  wherein:
 the metal particles are chosen from a group that includes gold, silver, platinum, palladium, and copper; and   the metal particles are between approximately two nanometers and approximately five micrometers in size.   
   
   
       13 . The method of  claim 12  wherein:
 sintering the metal particles comprises exposing the first metal layer, the layer of metal particles, the layer of organic molecules, and the second metal layer to electromagnetic radiation.   
   
   
       14 . The method of  claim 12  wherein:
 sintering the metal particles comprises heating the first metal layer, the layer of metal particles, the layer of organic molecules, and the second metal layer to a temperature between approximately 100 degrees Celsius and approximately 180 degrees Celsius.   
   
   
       15 . The method of  claim 12  further comprising:
 repeating the first immersing step and the second immersing step in alternating fashion until a film is formed between the first metal layer and the second metal layer, the film comprising alternating layers of the metal particles and the organic molecules and having a thickness between approximately two nanometers and approximately ten micrometers.   
   
   
       16 . The method of  claim 15  wherein:
 the organic molecules comprise a carbon chain having a length; and   the method further comprises selecting the length of the carbon chain.