Microelectronics package with inductive element and magnetically enhanced mold compound component

Patent metadata

Field	Value
Publication number	US-2017323804-A1
Application number	US-201615287273-A
Country	US
Kind code	A1
Filing date	Oct 6, 2016
Priority date	May 9, 2016
Publication date	Nov 9, 2017
Grant date	—

Abstract

The present disclosure relates to a microelectronics package with an inductive element and a magnetically enhanced mold compound component, and a process for making the same. The disclosed microelectronics package includes a module substrate, a thinned flip-chip die with an upper surface that includes a first surface portion and a second surface portion surrounding the first surface portion, the magnetically enhanced mold compound component, and a mold compound component. The thinned flip-chip die is attached to the module substrate and includes a device layer with an inductive element embedded therein. Herein, the inductive element is underlying the first surface portion and not underlying the second surface portion. The magnetically enhanced mold compound component is formed over the first surface portion. The mold compound component is formed over the second surface portion, not over the first surface portion, and surrounding the magnetically enhanced mold compound component.

First claim

What is claimed is:

1 . A method comprising:
providing a precursor package including a module substrate and a thinned flip-chip die with an upper surface that includes a first surface portion and a second surface portion surrounding the first surface portion, wherein the thinned flip-chip die is attached to the module substrate and comprises a device layer with a first inductive element that is embedded in the device layer, underlying the first surface portion, and not underlying the second surface portion; providing a first mold compound component over the second surface portion such that the first mold compound component does not cover the first surface portion; and providing a first magnetically enhanced mold compound component over the first surface portion to form a microelectronics package, wherein the first magnetically enhanced mold compound component is surrounded by the first mold compound component.

2 . The method of claim 1 wherein providing the precursor package comprises:
attaching a flip-chip die to an upper surface of the module substrate;
applying a second mold compound over the upper surface of the module substrate to encapsulate the flip-chip die;
curing the second mold compound to form a second mold compound component;
thinning the second mold compound component down to expose a back side of a silicon handle layer of the flip-chip die; and
removing substantially the entire silicon handle layer to form the thinned flip-chip die with the upper surface at a bottom of a first cavity.

3 . The method of claim 2 wherein applying the second mold compound is provided by one of a group consisting of sheet molding, overmolding, compression molding, transfer molding, dam fill encapsulation, and screen print encapsulation.

4 . The method of claim 1 wherein the precursor package further comprises a second mold compound component that resides over an upper surface of the module substrate, surrounds the thinned flip-chip die, and extends beyond the upper surface of the thinned flip-chip die to form a first cavity within the second mold compound component, wherein the upper surface of the thinned flip-chip die is exposed at a bottom of the first cavity.

5 . The method of claim 4 wherein providing the first mold compound component over the second surface portion comprises:
placing a molding block within the first cavity and over the first surface portion such that the first surface portion is blocked and the second surface portion is exposed to the first cavity;
applying the first mold compound to substantially fill the first cavity and directly contact the second surface portion;
curing the first mold compound to form the first mold compound component; and
removing the molding block to form a second cavity and expose the first surface portion at a bottom of the second cavity.

6 . The method of claim 5 further comprising thinning the first mold compound component to expose an upper surface of the molding block before removing the molding block.

7 . The method of claim 5 wherein the molding block is formed from polyimide with a thickness between 2 μm and 300 μm.

8 . The method of claim 5 wherein applying the first mold compound is provided by one of a group consisting of sheet molding, overmolding, compression molding, transfer molding, dam fill encapsulation, and screen print encapsulation.

9 . The method of claim 5 wherein providing a first magnetically enhanced mold compound component over the first surface portion comprises:
applying the first magnetically enhanced mold compound to substantially fill the second cavity and directly contact the first surface portion;
curing the first magnetically enhanced mold compound to form a first magnetically enhanced mold compound component; and
planarizing an upper surface of the first magnetically enhanced mold compound component such that the upper surface of the first magnetically enhanced mold compound component and the upper surface of the first mold compound component are coplanar.

10 . The method of claim 9 wherein applying the first magnetically enhanced mold compound is provided by one of a group consisting of sheet molding, overmolding, compression molding, transfer molding, dam fill encapsulation, and screen print encapsulation.

11 . The method of claim 4 wherein providing the first mold compound component over the second surface portion comprises:
applying the first mold compound to substantially fill the first cavity and directly contact the upper surface of the thinned flip-chip die;
curing the first mold compound to form the first mold compound component; and
removing a portion of the first mold compound component to form a second cavity, wherein the first surface portion is exposed at the bottom of the second cavity and the second surface portion is not exposed to the second cavity.

12 . The method of claim 11 further comprising planarizing an upper surface of the first mold compound before removing the portion of the first mold compound.

13 . The method of claim 11 wherein removing the portion of the first mold compound is provided by a laser ablation system.

14 . The method of claim 11 wherein applying the first mold compound is provided by one of a group consisting of sheet molding, overmolding, compression molding, transfer molding, dam fill encapsulation, and screen print encapsulation.

15 . The method of claim 11 wherein providing a first magnetically enhanced mold compound component over the first surface portion comprises:
applying the first magnetically enhanced mold compound to substantially fill the second cavity and directly contact the first surface portion;
curing the first magnetically enhanced mold compound to form a first magnetically enhanced mold compound component; and
planarizing an upper surface of the first magnetically enhanced mold compound component such that the upper surface of the first magnetically enhanced mold compound component and the upper surface of the first mold compound component are coplanar.

16 . The method of claim 15 wherein applying the first magnetically enhanced mold compound is provided by one of a group consisting of sheet molding, overmolding, compression molding, transfer molding, dam fill encapsulation, and screen print encapsulation.

17 . The method of claim 1 wherein the first magnetically enhanced mold compound component is formed from polymer mixed with at least one magnetically enhanced powder.

18 . The method of claim 17 wherein the at least one magnetically enhanced powder is ferro-magnetic material or ferri-magnetic material.

19 . The method of claim 17 wherein the at least one magnetically enhanced powder is sintered Magnesium-Zinc.

20 . The method of claim 1 wherein the first mold compound component has a thermal conductivity between 2.5 w/m·k and 50 w/m·k.

21 . The method of claim 1 wherein the thinned flip-chip die further comprises a dielectric layer over the device layer and a plurality of interconnects extending from a lower surface of the device layer and coupled to the module substrate.

22 . The method of claim 21 wherein the upper surface of the thinned flip-chip die is an upper surface of the dielectric layer.

Assignees

• Qorvo Us Inc

Inventors

• Costa Julio C
• Maxim George
• Leipold Dirk Robert Walter
• Scott Baker

Classifications

• H10W42/287

  materials for magnetic shielding, e.g. ferromagnetic materials · CPC title

• H10W42/284

  shielding resins · CPC title

• H10P95/06

  Planarisation of inorganic insulating materials · CPC title

• H10W90/734

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title