Method for Increasing Adhesion of Copper to Polymeric Surfaces

Abstract

Disclosed herein are methods and systems for conditioning a polymeric layer on a substrate to enable adhesion of a metal layer to the polymeric layer. Techniques may include conditioning the polymeric layer with nitrogen-containing plasma to generate a nitride layer on the surface of the polymeric layer. In another embodiment, the conditioning may include depositing a CuN layer using a lower power copper sputtering process in a nitrogen rich environment. Following the condition process, a higher power copper deposition or sputtering process may be used to deposit copper onto the polymeric layer with good adhesion properties.

1 . A system comprising:
 a surface energy chamber comprising:
 a first tray chuck; 
 an electrode adjacent to the first tray chuck, the electrode comprising one or more of the following: parallel plate electrode, a loop antenna, a helical antenna, or a magnetic coil; and 
 a power source in electrical communication with the electrode, the power comprising a radio frequency (RF) source or a microwave source; 
   a metal deposition chamber comprising:
 a second tray chuck; and 
 a metal sputtering target adjacent to the sputter tray chuck; 
   an encapsulated device tray handling system to move a tray of encapsulated electronic devices between the surface energy chamber and the metal deposition chamber.   
     
     
         2 . The system of  claim 1 , wherein the surface energy chamber uses the electrode and the power source to alter a surface energy or a surface state of the encapsulated electronic devices. 
     
     
         3 . The system of  claim 1 , wherein the system comprises a gas delivery system for a nitrogen gas or a noble gas. 
     
     
         4 . The system of  claim 3 , wherein the surface energy chamber can generate a nitrogen-containing plasma. 
     
     
         5 . The system of  claim 1 , wherein the surface energy chamber comprises a plasma etch chamber. 
     
     
         6 . The system of  claim 1 , wherein the encapsulated devices comprise:
 a protective cover that isolates the device from ambient conditions; and   electrical leads that can carry electrical current to or from the encapsulated device.   
     
     
         7 . The system of  claim 1 , wherein the metal target electrode comprises copper. 
     
     
         8 . The system of  claim 1 , wherein the encapsulated devices comprise a printed circuit board or at least two encapsulated devices that are coupled together to form the encapsulated device. 
     
     
         9 . The system of  claim 1 , wherein the encapsulated devices are electrically isolated from each other. 
     
     
         10 . The system of  claim 1 , wherein the tray comprises a JEDEC standard tray. 
     
     
         11 . The system of  claim 1 , wherein the encapsulated devices comprise a polymeric layer. 
     
     
         12 . The system of  claim 1 , wherein the encapsulated devices comprise a silicone impregnated epoxy. 
     
     
         13 . A system, comprising
 a surface treatment component that can improve adhesion of a metal layer to an electronic device by using a nitrogen-containing plasma;   a metal treatment component that can apply the metal layer to the electronic device comprising an electrical communication component; and   a tray movement system that can move a tray including the electronic device between the surface treatment component and the metal treatment component.   
     
     
         14 . The system of  claim 13 , wherein the electrical communication component comprises an electrical lead, a solder joint, or a ball contact 
     
     
         15 . The system of  claim 14 , wherein the electrical lead, the solder joint, or the ball contact is configured to be coupled to a printed circuit board or another electronic device. 
     
     
         16 . The system of  claim 13 , wherein the tray comprises a plurality of electronic devices. 
     
     
         17 . The system of  claim 13 , wherein the electronic device comprises a polymeric layer that is treated in the surface treatment component. 
     
     
         18 . The system of  claim 13 , wherein the electronic device comprises as a protective layer against electro-magnetic interference (EMI). 
     
     
         19 . The system of  claim 13 , wherein the surface treatment comprises a plasma electrode and the metal treatment component comprises a magnetron or a sputter target. 
     
     
         20 . A system, comprising:
 a first chamber comprising a means for altering a surface energy or a surface state of a plurality of encapsulated devices when they are disposed in the first chamber;   a second chamber comprising a means for depositing a metal layer on the plurality of encapsulated devices when they are disposed in the second chamber;   a tray movement apparatus comprising a means for moving a tray between the first chamber and the second chamber, the tray comprising the plurality of encapsulated devices.