Microelectronics package with inductive element and magnetically enhanced mold compound component

• US 10,062,583 B2
• Filed: 10/06/2016
• Issued: 08/28/2018
• Est. Priority Date: 05/09/2016
• Status: Active Grant

• Current Assignee: Qorvo US, Inc. (Qorvo, Inc.)
• Original Assignee: Qorvo US, Inc. (Qorvo, Inc.)
• Inventors: Costa, Julio C., Maxim, George, Leipold, Dirk Robert Walter, Scott, Baker
• Primary Examiner(s): Lee, Kyoung
• Assistant Examiner(s): SYLVIA, CHRISTINA A
• Application Number:
  US15/287,273
• Publication Number:
  US 20170323804A1
• Time in Patent Office: 691 Days
• CPC Class Codes: H01L 21/31051 Planarisation of the insulating layers H01L21/31058 takes precedence
• CPC Class Codes: H01L 21/565 Moulds
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2224/2929 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29318 Zinc [Zn] as principal constituent
• CPC Class Codes: H01L 2224/29323 Magnesium [Mg] as principal constituent
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 23/18 Fillings characterised by the material, its physical or chemical properties, or its arrangement within the complete device
• CPC Class Codes: H01L 23/293 Organic, e.g. plastic
• CPC Class Codes: H01L 23/295 containing a filler H01L23/296 takes precedence
• CPC Class Codes: H01L 23/3114 the device being a chip scale package, e.g. CSP
• CPC Class Codes: H01L 23/3121 a substrate forming part of the encapsulation
• CPC Class Codes: H01L 23/3135 Double encapsulation or coating and encapsulation
• CPC Class Codes: H01L 23/645 Inductive arrangements H01L23/647, H01L23/66 take precedence
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 24/29 of an individual layer connector
• CPC Class Codes: H01L 24/32 : of an individual layer connector
• CPC Class Codes: H01L 24/81 : using a bump connector
• CPC Class Codes: H01L 28/10 : Inductors
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01012 : Magnesium [Mg]
• CPC Class Codes: H01L 2924/0103 : Zinc [Zn]
• CPC Class Codes: H01L 2924/013 : Alloys
• CPC Class Codes: H01L 2924/07025 : Polyimide
• CPC Class Codes: H01L 2924/186 : Material
• CPC Class Codes: H01L 2924/19042 : being an inductor

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.

Claims

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 μ

m and 300 μ

m.

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.