Granted Patent B2

US 7,749,882 · App. 11/509,441 · Granted Jul 6, 2010

Assignee: Micron Technology, Inc.

Abstract

Claims (47)

1. A method of forming a plurality of microelectronic devices on a semiconductor workpiece having a plurality of microelectronic dies, the method comprising:

attaching a plurality of first solder ball interconnect elements on corresponding terminals of the semiconductor workpiece;

molding a protective layer onto the workpiece with the layer covering only a portion of individual first solder ball interconnect elements;

reconfiguring the first solder ball interconnect elements without removing material from the first solder ball interconnect elements, such that a top surface of the plurality of first solder ball interconnect elements located opposite the corresponding terminals is reconfigured to include a flat surface spaced apart from the protective layer; and

after reconfiguring the first solder ball interconnect elements, attaching a plurality of second solder ball interconnect elements on the flat surface of corresponding first solder ball interconnect elements.

2. The method of claim 1 wherein reconfiguring the first solder ball interconnect elements comprises heating the first solder ball interconnect elements.

3. The method of claim 1 , further comprising forming an alignment feature on the workpiece before reconfiguring the first solder ball interconnect elements.

4. The method of claim 1 , wherein reconfiguring the first solder ball interconnect elements comprises reshaping the first solder ball interconnect elements without grinding the first solder ball interconnect elements.

5. The method of claim 1 wherein the semiconductor workpiece comprises a first side and a second side opposite the first side, and wherein the method further comprises:

marking the first side of the workpiece with a first alignment feature; and

placing a second alignment mark on the protective layer.

6. The method of claim 1 wherein:

attaching the plurality of first solder ball interconnect elements comprises placing the plurality of first solder ball interconnect elements on a side of a semiconductor workpiece;

reconfiguring the first solder ball interconnect elements comprises reshaping the first solder ball interconnect elements by heating the first solder ball interconnect elements; and

attaching the plurality of second solder ball interconnect elements on corresponding first solder ball interconnect elements comprises coupling the second solder ball interconnect elements to corresponding first solder ball interconnect elements.

7. The method of claim 6 wherein:

the semiconductor workpiece comprises a redistribution structure on the dies, the redistribution structure including a plurality of terminals;

attaching the first solder ball interconnect elements on the workpiece comprises forming the first solder ball interconnect elements on corresponding terminals of the redistribution structure;

the first solder ball interconnect elements individually comprise a proximal end at the side of the workpiece and a distal end opposite the proximal end;

reconfiguring the first solder ball interconnect elements comprises forming the flat surface at the distal end of the individual first solder ball interconnect elements;

coupling the second solder ball interconnect elements comprises attaching the second solder ball interconnect elements to the flat surfaces of the corresponding first solder ball interconnect elements; and

the method further comprises (a) cutting the semiconductor workpiece to separate the dies after coupling the second solder ball interconnect elements, and (b) attaching a separated die to a support member with the second solder ball interconnect elements attached to corresponding pads on the support member.

8. The method of claim 6 wherein:

the first solder ball interconnect elements individually comprise a proximal end at the side of the workpiece and a distal end opposite the proximal end; and

reconfiguring the first solder ball interconnect elements comprises forming the flat surface at the distal end of the first solder ball interconnect elements.

9. The method of claim 6 wherein reconfiguring the first solder ball interconnect elements comprises reconfiguring the first solder ball interconnect elements without removing material from the first solder ball interconnect elements.

10. The method of claim 6 wherein reconfiguring the first solder ball interconnect elements comprises reconfiguring the first solder ball interconnect elements without removing material from the layer.

11. The method of claim 6 wherein:

the semiconductor workpiece comprises a redistribution structure on the dies, the redistribution structure including a plurality of terminals; and

attaching the first solder ball interconnect elements on the workpiece comprises forming the first solder ball interconnect elements on corresponding terminals of the redistribution structure.

12. The method of claim 6 wherein:

the plurality of dies have an integrated circuit and a plurality of terminals operably coupled to the integrated circuit; and

attaching the first solder ball interconnect elements on the workpiece comprises forming the first solder ball interconnect elements on corresponding terminals of the dies.

13. The method of claim 6 wherein:

the plurality of dies having an integrated circuit and a plurality of terminals operably coupled to the integrated circuit;

attaching the first solder ball interconnect elements on the workpiece comprises forming the first solder ball interconnect elements on the side of the workpiece with the first solder ball interconnect elements electrically connected to corresponding terminals on the dies; and

the method further comprises cutting the workpiece to separate the dies after coupling the detached second solder ball interconnect elements.

14. The method of claim 6 wherein:

forming the layer comprises constructing the layer with an end portion of the first solder ball interconnect elements projecting a first distance from the layer; and

reconfiguring the first solder ball interconnect elements comprises reconfiguring the first solder ball interconnect elements with the end portion of the first solder ball interconnect elements projecting a second distance from the layer, the second distance being less than the first distance.

15. The method of claim 1 wherein reconfiguring the first solder ball interconnect elements without removing material from the first solder ball interconnect elements comprises heating the first solder ball interconnect elements and contacting the first solder ball interconnect elements with a press.

16. A method of forming microelectronic devices on a semiconductor workpiece, comprising:

attaching first solder ball interconnect elements to terminals of the semiconductor workpiece;

depositing mold compound onto a surface of the semiconductor workpiece;

clamping the semiconductor workpiece in a mold, the mold comprising a first mold portion having a compressible release tape configured to contact the mold compound and deform around a portion of the first solder ball interconnect elements, and a second mold portion configured to contact an opposite side of the semiconductor workpiece, wherein clamping the semiconductor workpiece in the mold comprises spreading the mold compound across the surface of the semiconductor workpiece to form a protective layer on the workpiece, and wherein the first solder ball interconnect elements protrude from the protective layer;

reconfiguring the first solder ball interconnect elements without removing material from the first solder ball elements to have a flat top surface spaced apart from an exposed surface of the protective layer in a different plane;

after reconfiguring the first solder ball interconnect elements, attaching second solder ball interconnect elements on the flat surface of the first solder ball interconnect elements.

Assignments (8)

Continuity (1)