Chip package and fabrication method thereof

• US 10,049,252 B2
• Filed: 12/11/2015
• Issued: 08/14/2018
• Est. Priority Date: 12/15/2014
• Status: Active Grant

• Current Assignee: Xintec Incorporated
• Original Assignee: Xintec Incorporated
• Inventors: Ho, Yen-Shih, Chang, Shu-Ming, Liu, Tsang-Yu, Shen, Hsing-Lung
• Primary Examiner(s): Nguyen, Hoai-An D
• Application Number:
  US14/967,153
• Publication Number:
  US 20160171273A1
• Time in Patent Office: 977 Days
• Field of Search: 324500, 324519, 324548, 324600, 324649, 324658, 324661, 324662, 324663, 324669, 324671, 324684, 324686, 32475017, 702 47, 702 52, 345173, 345174
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: H01L 2224/141 Disposition
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation

Abstract

A chip package includes a substrate, a capacitive sensing layer and a computing chip. The substrate has a first surface and a second surface opposite to the first surface, and the capacitive sensing layer is disposed above the second surface and having a third surface opposite to the second surface, which the capacitive sensing layer includes a plurality of capacitive sensing electrodes and a plurality of metal wires. The capacitive sensing electrodes are on the second surface, and the metal wires are on the capacitive sensing electrodes. The computing chip is disposed above the third surface and electrically connected to the capacitive sensing electrodes.

Claims

1. A chip package, comprising:

a substrate having a first surface and a second surface opposite to the first surface;

a capacitive sensing layer disposed below the first surface and having a third surface opposite to the first surface, the capacitive sensing layer comprising;

a plurality of capacitive sensing electrodes disposed on the third surface, and

a plurality of metal wires disposed on the capacitive sensing electrodes

a computing chip disposed above the capacitive sensing layer and electrically connected to the capacitive sensing electrodes; and

a recess extending from the second surface to the first surface to expose the metal wires, and the computing chip is in the recess.

2. The chip package of claim 1, further comprising a through hole extending from the second surface to the first surface to expose the metal wires.

3. The chip package of claim 2, further comprising:

an isolation layer disposed above the second surface and extending into the through hole to cover sidewalls of the through hole;

a redistribution layer disposed above the isolation layer and extending into the through hole to contact the metal wires;

a passivation layer disposed above the redistribution layer, and the passivation layer having a plurality of first openings and second openings exposing the redistribution layer;

a plurality of first external conductive connections respectively in the first openings to contact the redistribution layer; and

a plurality of second external conductive connections respectively in the second openings to contact the redistribution layer.

4. The chip package of claim 3, wherein the computing chip is disposed above the second surface and the second external conductive connections.

5. The chip package of claim 4, wherein the first external conductive connections are electrically connected to the computing chip via the redistribution layer and the second external conductive connections.

6. The chip package of claim 1, further comprising:

an isolation layer disposed above the second surface and extending into the recess to cover sidewalls of the recess;

a redistribution layer disposed above the isolation layer and extending into the recess to contact the metal wires;

a passivation layer disposed above the redistribution layer, and the passivation layer having a plurality of first openings exposing the redistribution layer above the second surface;

a plurality of first external conductive connections respectively in the first openings to contact the redistribution layer, and the first external conductive connections being electrically connected to the computing chip; and

a plurality of second external conductive connections in the recess to contact the redistribution layer.

7. The chip package of claim 6, wherein the computing chip is disposed above the second external conductive connections.

8. The chip package of claim 7, wherein the first external conductive connections are electrically connected to the computing chip via the redistribution layer and the second external conductive connections.

9. The chip package of claim 7, further comprising a protecting layer in the recess to cover the computing chip and the second external conductive connections.

10. The chip package of claim 1, wherein the substrate comprises silicon.

11. A method of fabricating a chip package, comprising:

receiving a substrate having a first surface and a second surface opposite to the first surface;

forming a capacitive sensing layer below the first surface, and the capacitive sensing layer having a third surface opposite to the first surface, the capacitive sensing layer being formed by;

forming a plurality of metal wires below the first surface; and

forming a plurality of capacitive sensing electrodes below the metal wires;

forming a computing chip above the capacitive sensing layer to electrically connect the capacitive sensing electrodes and the computing chip; and

forming a recess extending from the second surface to the first surface to expose the metal wires, and the computing chip being formed in the recess.

12. The method of fabricating the chip package of claim 11, further comprising:

forming a through hole extending from the second surface to the first surface to expose the metal wires.

13. The method of fabricating the chip package of claim 12, further comprising:

forming an isolation layer above the second surface and in the through hole;

removing a portion of the isolation layer to expose the metal wires;

forming a redistribution layer above the isolation layer and extending into the through hole to contact the metal wires;

forming a passivation layer above the redistribution layer;

removing a portion of the passivation layer to form a plurality of first openings and second openings exposing the redistribution layer;

forming a plurality of first external conductive connections respectively in the first openings; and

forming a plurality of second external conductive connections respectively in the second openings, and the computing chip being formed above the second external conductive connections.

14. The method of fabricating the chip package of claim 13, wherein the first external conductive connections and the second external conductive connections are simultaneously formed in the same process step.

15. The method of fabricating the chip package of claim 13, further comprising dicing the substrate and the capacitive sensing layer along a scribe line to form the chip package.

16. The method of fabricating the chip package of claim 11, further comprising forming a recess extending from the second surface to the first surface to expose the metal wires, and the computing chip being formed in the recess.

17. The method of fabricating the chip package of claim 16, further comprising:

forming an isolation layer above the second surface and in the recess;

removing a portion of the isolation layer to expose the metal wires;

forming a redistribution layer above the isolation layer and extending into the recess to contact the metal wires;

forming a passivation layer to cover the redistribution layer above the second surface;

removing a portion of the passivation layer to form a plurality of first openings exposing the redistribution layer above the second surface;

forming a plurality of first external conductive connections respectively in the first openings; and

forming a plurality of second external conductive connections in the recess, and the computing chip being formed above the second external conductive connections.

18. The method of fabricating the chip package of claim 17, wherein the first external conductive connections and the second external conductive connections are simultaneously formed in the same process step.

19. The method of fabricating the chip package of claim 17, further comprising forming a protecting layer in the recess to cover the computing chip and the second external conductive connections.

20. The method of fabricating the chip package of claim 19, further comprising dicing the substrate and the capacitive sensing layer along a scribe line to form the chip package.