Bonding tool for mounting semiconductor chips
View Patent ↗A vacuum bonding tool method for pick-and-place and bonding semiconductor chips onto a substrate or onto a previously mounted die to form a die stack includes a shank and a suction part. The shank has a vacuum conduit extending from a first end to a second end of the shank. The shank is adapted for cooperative engagement with the suction part at the second end, and the shank has a plate at the second end to support the suction part. The suction part has a surface for contacting a semiconductor chip during pick-and place operation. According to the invention, the suction part is made of an elastically deformable conductive or non-conductive material. In various embodiments, the chip contacting surface of the elastically deformable suction part flat overall, or is concave, of has a flat central region and concave regions.
1. A method of bonding a semiconductor die, comprising:
providing a die bonding tool having a shank and suction part, the shank having a conduit for drawing a vacuum from a first end of the shank, the suction part being disposed on a second end of the shank and having a die contacting surface, the die contacting surface having a flat portion proximate to a center area of the suction part and a convex portion extending from the flat portion to an outer area of the suction part, the suction part further including an opening on the flat portion and openings on the convex portion, the openings providing pneumatic communication between the conduit of the shank and the die contacting surface;
disposing the die contacting surface on the semiconductor die; and
elastically deforming the suction part so that the convex portion and associated openings flatten to be planar with the flat portion upon application of pressure to the shank to bond to the semiconductor die.
2. The method of claim 1 , wherein the suction part is made with a polymer.
3. The method of claim 2 , wherein the polymer is a silicone-based material.
4. The method of claim 1 , wherein the openings are distributed over the die contacting surface.
5. The method of claim 1 , wherein the outer area of the suction part returns to a convex shape upon removal of the pressure to the shank.
6. The method of claim 1 , wherein a semiconductor die attaches to the die contacting surface when vacuum and pressure are applied, the die contacting surface conforming to the semiconductor die upon removal of the pressure to the shank.
7. A method of bonding a semiconductor die, comprising:
providing a die bonding tool having a shank and suction part, the shank having a conduit for drawing a vacuum from a first end of the shank, the suction part being disposed on a second end of the shank and having a die contacting surface, the die contacting surface having a flat portion proximate to a center area of the suction part and a convex portion extending from the flat portion to an outer area of the suction part, the convex surface having a plurality of openings providing pneumatic communication between the conduit of the shank and the die contacting surface;
disposing the die contacting surface on the semiconductor die; and
elastically deforming the suction part so that the convex surface and openings flatten upon application of pressure to the shank to bond to the semiconductor die.
8. The method of claim 7 , wherein the suction part further includes an opening on the flat portion.
9. The method of claim 7 , wherein the suction part is made with a polymer.
10. The method of claim 9 , wherein the polymer is a silicone-based material.
11. The method of claim 7 , wherein the convex portion has a height of 10-400 micrometers.
12. The method of claim 7 , wherein the openings are distributed over the die contacting surface.
13. The method of claim 7 , wherein the outer area of the suction part returns to a convex shape upon removal of the pressure to the shank.
14. A method of bonding a semiconductor die, comprising:
providing a die bonding tool having a shank and suction part having a die contacting surface, the die contacting surface having a flat portion proximate to a center area of the suction part and a convex portion extending from the flat portion to an outer area of the suction part, the convex surface having a plurality of openings providing pneumatic communication between a conduit of the shank and the die contacting surface;
disposing the die contacting surface on the semiconductor die; and
elastically deforming the suction part so that the convex surface and openings flatten upon application of pressure to the shank to bond to the semiconductor die.
15. The method of claim 14 , wherein the suction part further includes an opening on the flat portion.
16. The method of claim 14 , wherein the suction part is made with a polymer.
17. The method of claim 16 , wherein the polymer is a silicone-based material.
18. The method of claim 14 , wherein the openings are distributed over the die contacting surface.
19. The method of claim 14 , wherein the convex portion has a height of 10-400 micrometers.
20. The method of claim 14 , wherein the outer area of the suction part returns to a convex shape upon removal of the pressure to the shank.
21. A method of bonding a semiconductor die, comprising:
providing a die bonding tool having a shank and suction part, the suction part having a die contacting surface, the die contacting surface having a flat portion proximate to a center area of the suction part and a convex portion extending from the flat portion to an outer area of the suction part;
disposing the die contacting surface on the semiconductor die; and
elastically deforming the suction part so that the convex portion flattens to be planar with the flat portion upon application of pressure to the shank to bond to the semiconductor die.
22. The method of claim 21 , wherein the suction part is made with a polymer.
23. The method of claim 22 , wherein the polymer is a silicone-based material.
24. The method of claim 21 , wherein the convex surface has a plurality of openings providing pneumatic communication between a conduit of the shank and the die contacting surface.
25. The method of claim 21 , wherein the outer area of the suction part returns to a convex shape upon removal of the pressure to the shank.