SMALL SIZE AND FULLY INTEGRATED POWER CONVERTER WITH MAGNETICS ON CHIP

• US 20130056847A1
• Filed: 10/14/2011
• Published: 03/07/2013
• Est. Priority Date: 09/06/2011
• Status: Active Grant

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: CHEN, Baoxing
• Granted Patent: US 8,558,344 B2
• Time in Patent Office: Days
• US Class Current: 257/531
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 2017/0066 with a magnetic layer
• CPC Class Codes: H01F 2017/0086 on semiconductor substrate inductors for integrated circuits H01L28/10
• CPC Class Codes: H01F 27/022 Encapsulation
• CPC Class Codes: H01F 27/24 Magnetic cores
• CPC Class Codes: H01F 27/29 Terminals; Tapping arrangements for signal inductances
• CPC Class Codes: H01F 3/14 Constrictions; Gaps, e.g. air-gaps in magnetic shunt paths H01F3/12
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 23/50 for integrated circuit devices, e.g. power bus, number of leadsH01L23/482 - H01L23/498 take precedence
• CPC Class Codes: H01L 23/5227 Inductive arrangements or effects of, or between, wiring layers other inductive arrangements H01L23/645
• CPC Class Codes: H01L 27/016 Thin-film circuits
• CPC Class Codes: H01L 28/10 Inductors
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49071 by winding or coiling

Abstract

An integrated circuit has a semiconductor die provided in a first IC layer and an inductor fabricated on a second IC layer. The inductor may have a winding and a magnetic core, which are oriented to conduct magnetic flux in a direction parallel to a surface of a semiconductor die. The semiconductor die may have active circuit components fabricated in a first layer of the die, provided under the inductor layer. The integrated circuit may include a flux conductor provided on a side of the die opposite the first layer. PCB connections to active elements on the semiconductor die may progress through the inductor layer as necessary.

Claims

1. An integrated circuit, comprising:

a semiconductor die having active circuit components fabricated in a first surface thereof,

an inductor layer provided over the first surface of the semiconductor die, comprising an inductor with a magnetic core, a winding of the inductor oriented to conduct flux in a direction generally parallel to the first surface of the semiconductor die, and

a flux conductor provided on a second surface of the semiconductor die opposite to the first surface.

2. The integrated circuit of claim 1, wherein the integrated circuit has a package configuration for chip scale packaging.

3. The integrated circuit of claim 1, wherein the integrated circuit has a package configuration size to match a larger area between an area of the active circuit components and the inductor.

4. The integrated circuit of claim 1, further comprising an encapsulant covering the active circuit components and inductor.

5. The integrated circuit of claim 1, further comprising a connector coupling a terminal of the inductor to an active circuit component on the first surface of the semiconductor die.

6. The integrated circuit of claim 1, further comprising a connector extending from a package of the integrated circuit, the connector coupled to a terminal of the inductor.

7. The integrated circuit of claim 6, further comprising a second connector extending from a package of the integrated circuit, the connector coupled to a conductor that passes through the inductor layer and connects to an active circuit component on the first surface of the semiconductor die.

8. The integrated circuit of claim 1, wherein the magnetic core is a solid core.

9. The integrated circuit of claim 1, wherein the magnetic core is multi-segment core having a dielectric material provided in voids between adjacent segments.

10. The integrated circuit of claim 1, wherein the inductor layer includes at least two inductors.

11. The integrated circuit of claim 1, wherein the inductor further comprises a second magnetic core generally aligned with the first magnetic core and the inductor winding is provided as separate spirals around each of the magnetic cores, each spiral generating flux in an opposite direction to the other spiral in response to a common signal through the winding.

12. An integrated circuit, comprising:

a semiconductor die having active circuit components fabricated in a first surface thereof,

an inductor layer provided over a first surface of the semiconductor die, the inductor layer comprising an inductor winding provided around a magnetic core, the winding of the inductor oriented to conduct flux in a direction generally parallel to the first surface of the semiconductor die, wherein the inductor is electrically connected to at least one active circuit component; and

a flux conductor provided on a second surface of the semiconductor die opposite to the first surface.

13. The integrated circuit of claim 12, wherein the integrated circuit has a package configuration for chip scale packaging.

14. The integrated circuit of claim 12, wherein the magnetic core and flux conductor are made of a common material.

15. The integrated circuit of claim 12, further comprising a connector extending from a package of the integrated circuit, the connector coupled to a terminal of the inductor.

16. The integrated circuit of claim 15, further comprising a second connector extending from a package of the integrated circuit, the connector coupled to a conductor that passes through the inductor layer and connects to an active circuit component on the first surface of the semiconductor die.

17. The integrated circuit of claim 12, wherein the magnetic core is a solid core.

18. The integrated circuit of claim 12, wherein the magnetic core is multi-segment core having a dielectric material provided in voids between adjacent segments.

19. The integrated circuit of claim 12, wherein the inductor layer includes at least two inductors.

20. The integrated circuit of claim 12, wherein the inductor further comprises a second magnetic core generally aligned with the first magnetic core and the inductor winding is provided as separate spirals around each of the magnetic cores, each spiral generating flux in an opposite direction to the other spiral in response to a common signal through the winding.

21. An integrated circuit, comprising:

a semiconductor die having active circuit components fabricated in a first surface thereon and having at least one through silicon via (TSV); and

an inductor layer provided over a second surface of the semiconductor die opposite to the first surface, the inductor layer comprising an inductor winding provided around a magnetic core, the winding of the inductor oriented to conduct flux in a direction generally parallel to the first surface of the semiconductor die, wherein the inductor is electrically connected to at least one active circuit component in an electrical path that extends through the TSV.

22. The integrated circuit of claim 21, wherein the integrated circuit has a package configuration for chip scale packaging.

23. The integrated circuit of claim 21, further comprising a connector extending from a package of the integrated circuit, the connector coupled to a terminal of the inductor.

24. The integrated circuit of claim 21, wherein the magnetic core is a solid core.

25. The integrated circuit of claim 21, wherein the magnetic core is multi-segment core having a dielectric material provided in voids between adjacent segments.

26. The integrated circuit of claim 21, wherein the magnetic core is a multi-segment core in which a first portion of the winding spirals around a first segment in a first flux-generating orientation and a second portion of the winding spirals around a second segment in a second flux-generating orientation opposite to the first flux-generating orientation.

27. The integrated circuit of claim 21, wherein the magnetic core is a multi-segment core in which a first portion of the winding spirals around a first segment in a first flux-generating orientation and a second portion of the winding spirals around a second segment in a second flux-generating orientation opposite to the first flux-generating orientation.

28. The integrated circuit of claim 21, wherein the magnetic core is a multi-segment core in which the winding spirals around a first segment to generate flux is a first path, and second and third segments are provided adjacent to the first segment to provide a return flux path.

29. The integrated circuit of claim 21, wherein the magnetic core is a multi-segment core providing a closed loop for flux, wherein an inductor winding is provided on a segment of the core aligned with an easy axis of core material.

30. The integrated circuit of claim 21, wherein the inductor layer includes at least two inductors.