Electronic package having down-set leads and method
View Patent ↗In one embodiment, a leadless package includes down-set conductive leads having base portions. The base portions include stand-offs that attach to electrodes on an electronic chip using, for example, a solder die attach material. An optional encapsulating layer covers portions of the down-set conductive leads and portions of the electronic chip while leaving pad portions of the down-set conductive leads and a surface of the electronic chip exposed. The pad portions and the surface of the electronic chip are oriented to attach to a next level of assembly.
1. A package structure comprising:
an electronic chip having a first bonding surface with a first electrode, and a second bonding surface opposite the first bonding surface, wherein the electronic chip is bumpless; and
a first down-set conductive lead having a first base portion and a first stand-off, wherein the first stand-off is formed as part of the first base portion, and wherein the first stand-off has an attachment area that corresponds to the area of the first electrode, and wherein the attachment area is smaller than the first electrode, and wherein the first stand-off is connected to the first electrode.
2. The package of claim 1 further comprising an encapsulating layer covering at least a portion of the first down-set conductive lead and at least a portion of the electronic chip.
3. The package of claim 2 , wherein a surface of the first base portion is exposed.
4. The package of claim 2 wherein the first down-set conductive lead includes a first pad portion, and wherein a portion of the first pad portion and the second bonding surface are exposed.
5. The package of claim 2 wherein the encapsulating layer comprises an overmolded encapsulating material.
6. The package of the claim 1 wherein the first electrode comprises a solderable metal.
7. The package of claim 1 wherein at least a portion of the first down-set conductive lead is undulating.
8. The package of claim 1 further comprising a conductive plate coupled to the second bonding surface.
9. The package of claim 1 further comprising a second down-set conductive lead, wherein the second down-set conductive lead includes a second stand-off and a second pad portion, and wherein the electronic chip further includes a second electrode on the first bonding surface, and wherein the second electrode is coupled to the second stand-off.
10. The package of claim 9 further comprising a third down-set conductive lead, wherein the second bonding surface is coupled to the third down-set conductive lead with an attachment structure.
11. The package of claim 10 wherein the attachment structure comprises a clip.
12. The package structure of claim 1 further comprising a second down-set conductive lead spaced apart from the electronic chip, and wherein a connective device couples the second down-set conductive lead to a second electrode on the electronic chip.
13. The package structure of claim 12 wherein the connective device comprises a wire bond.
14. An electronic package structure comprising:
a first down-set conductive lead including a first pad portion and a first base portion having a first raised pedestal;
a second down-set conductive lead including a second pad portion and a second base portion;
a first electronic chip having first and second contacts on a first surface, wherein the first contact is coupled to the first raised pedestal, and wherein the electronic chip is bumpless;
a first connective device coupling the second base portion to the second contact;
a third down-set conductive lead including a third pad portion and a third base portion; and
a second connective device coupling a second surface of the first electronic chip to the third base portion.
15. The electronic package structure of claim 14 further comprising an encapsulating layer covering at least a portion of the first down-set conductive lead and at least a portion of the first electronic chip.
16. The electronic package structure of claim 15 wherein a surface of the first base portion is exposed.
17. The electronic package structure of claim 14 wherein the first connective device comprises a second raised pedestal formed on the second base portion.
18. The electronic package structure of claim 14 wherein the first connective device comprises a wire bond.
19. The electronic package structure of claim 14 further comprising:
a fourth down-set conductive lead including a fourth pad portion and a fourth base portion having a third raised pedestal;
a fifth down-set conductive lead including a fifth pad portion and a fifth base portion;
a second electronic chip having a third contact coupled to the third raised pedestal; and
a second connective device coupling the second electronic chip to the fifth down-set conductive lead.
20. The electronic package structure of claim 14 wherein the second connective device comprises a clip.
21. The electronic package structure of claim 14 wherein a portion of the first down-set conductive lead is undulating.