Flexible diode package and method of manufacturing
View Patent ↗A single step packaging process that both melts a solder and also cures an adhesive about a microelectronic circuit. The process finds technical advantages by simplifying packaging of a die that may be coupled to a planar flexible lead, which leads to a lower production cost and quicker manufacturing time. The planar flexible lead may be adapted to bend and flex during mechanical stress and during extreme temperature cycling, and allow direct mounting of the device to a member by easily welding or soldering. The invention may comprise a flexible solar cell diode that can be closely positioned on solar panels at an extremely low cost.
1. A method of packaging an integrated circuit with a first lead and a second lead, the method comprising the steps of:
disposing a first member upon the first lead to define a recess;
disposing a first solder preform in the recess; disposing a die upon the first solder preform;
disposing a second solder preform upon the die;
disposing a second member upon the first member;
disposing the second lead upon the second member and over the die; and
heating all of the above elements at a predetermined temperature to simultaneously both melt the first and second solder preforms and also seal the first and second members to each other to form a seal about the die in a single step.
2. The method as specified in claim 1 wherein at least one of the first or second members comprises a polymide.
3. The method as specified in claim 2 wherein the polymide includes an adhesive.
4. The method as specified in claim 3 wherein the adhesive is an acrylic based adhesive.
5. The method as specified in claim 1 wherein both the first and second members comprise a polymide.
6. The method as specified in claim 5 wherein both of the first and second members comprise an adhesive.
7. The method as specified in claim 6 wherein both the first lead and the second lead are planar flexible leads.
8. The method as specified in claim 7 further comprising disposing a spacer member upon the second solder preform.
9. The method as specified in claim 8 further comprising disposing a third solder perform upon the spacer member.
10. The method as specified in claim 7 wherein further comprising disposing a third member between the first member and the second member.
11. The method as specified in claim 10 wherein the first member is bonded to the first planar flexible lead, and the second member is bonded to the second planar flexible lead, before the third member is disposed between the first member and the second member.
12. The method as specified 11 wherein the first member, the second member, and the third member are comprised of polymide.
13. The method as specified in claim 12 wherein the third member includes an adhesive.
14. The method as specified in claim 13 wherein the adhesive is an acrylic adhesive.
15. The method as specified in claim 7 wherein the die is a solar diode.
16. The method as specified in claim 6 wherein the predetermined temperature is greater than a melting temperature of the solder preforms and the adhesive.
17. The method as specified in claim 16 wherein the predetermined temperature is greater than about 300 degrees Centigrade.
18. The method as specified in claim 1 wherein the first lead comprises a cathode and the second lead comprises an anode.
19. The method as specified in claim 1 wherein all the elements are compressed in a stack while heated.
20. The method as specified in claim 1 wherein all the elements are assembled in an assembly fixture.