Encapsulated stack of dice and support therefor
Systems and methods for encapsulating a stack of semiconductor dice are described. A stack of semiconductor dice may be formed, for example by attaching die to flexible printed circuit supports attached to frames and stacking the supports, and then encapsulated by flowing a liquid encapsulant around the stack of dice and solidifying the liquid encapsulant. The die supports may contain encapsulant flow openings, such as rectangular slits, that allow the liquid encapsulant to flow around the stack of dice.
1. A device comprising:
a first die attached to a first printed circuit stacked over a second die attached to a second printed circuit, at least one of the first printed circuit and the second printed circuit having an encapsulant flow opening; and
an encapsulant over the first printed circuit, over the first die, continuously through the encapsulant flow opening from one side of the printed circuit to another side of the printed circuit, over the second printed circuit, and over the second die,
wherein the first printed circuit and the second printed circuit each comprise a flexible sheet attached to a frame, and wherein each of the frames has an alignment opening to accommodate a jig to allow the first die to be aligned relative to the second die.
2. The device of claim 1 , wherein the first printed circuit and the second printed circuit each have signaling mediums, and wherein the encapsulant flow opening includes a slit.
3. The device of claim 2 , wherein a width of the slit is between 0.5–2 millimeters, and wherein a length of the slit is greater than 2 millimeters.
4. The device of claim 1 , wherein the encapsulant is on a surface of the second die.
5. The device of claim 1 , wherein the first die is attached to the first printed circuit at a position that depends on defect information.
6. The device of claim 1 , further comprising Flash memory, and wherein the device is included in a cellular phone.
7. The device of claim 1 , wherein the device comprises a package having a thickness of less than one millimeter.
8. A device comprising:
stacked dice;
an encapsulant around the stacked dice including contiguously through an encapsulant flow opening in a printed circuit support from one side of the printed circuit support to another side of the printed circuit support;
a plurality of encapsulant flow openings on opposite sides of a die attach position, wherein the plurality of encapsulant flow openings comprise slits on all four sides of the die attach position.
9. The device of claim 8 , wherein the dice are stacked based on die attach position defect information and die defect information.
10. The device of claim 8 , further comprising Flash memory, and wherein the device is included in a cellular phone.
11. The device of claim 8 , wherein a thickness of the encapsulated stacked dice is less than one millimeter.
12. A device comprising:
a printed circuit;
a die attach position on the printed circuit; and
a plurality of encapsulant flow openings through the printed circuit to allow a liquid encapsulant to flow from one side of the printed circuit to another,
wherein the plurality of encapsulant flow openings include a plurality of elongated rectangular slits proximate the die attach position along a plurality of sides of the die attach position.
13. The device of claim 12 , wherein the printed circuit comprises a flexible printed circuit.
14. The device of claim 12 , wherein a slit comprises a width that is between 0.5–2 millimeters and a length that is greater than 2 millimeters.
15. The device of claim 12 , wherein the slits are on opposite sides of the die attach position.
16. The device of claim 15 , wherein the slits are on all four sides of the die attach position.
17. The device of claim 12 , further comprising:
a plurality of die attach positions; and
a plurality of encapsulant flow openings proximate each of the plurality of die attach positions.
18. The device of claim 12 , further comprising:
a frame having a plurality of alignment teeth; and
a plurality of openings of the printed circuit corresponding to the plurality of alignment teeth.