METHOD OF MANUFACTURING AN INDUCTOR FOR A MICROELECTRONIC DEVICE, METHOD OF MANUFACTURING A SUBSTRATE CONTAINING SUCH AN INDUCTOR, AND SUBSTRATE MANUFACTURED THEREBY

• US 20110302771A1
• Filed: 08/23/2011
• Published: 12/15/2011
• Est. Priority Date: 06/11/2008
• Status: Active Grant

• Current Assignee: Aleksandar Aleksov, Gloria Alejandra Camacho-Bragado
• Original Assignee: Aleksandar Aleksov, Gloria Alejandra Camacho-Bragado
• Inventors: Aleksov, Aleksandar, Camacho-Bragado, Gloria Alejandra
• Granted Patent: US 8,621,744 B2
• Time in Patent Office: Days
• US Class Current: 29/602.1
• CPC Class Codes: H01F 17/0033 with the coil helically wound around a magnetic core
• CPC Class Codes: H01F 17/062 Toroidal core with turns of coil around it
• CPC Class Codes: H01F 2017/0073 with a special conductive pattern, e.g. flat spiral
• CPC Class Codes: H01F 41/046 structurally combined with ferromagnetic material
• CPC Class Codes: H01F 41/16 the magnetic material being applied in the form of particles, e.g. by serigraphy , to form thick magnetic films or precursors therefor H01F41/18 -H01F41/24 take precedence
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 23/498 Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers shape of the substrate H01L23/13
• 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 23/645 Inductive arrangements H01L23/647, H01L23/66 take precedence
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49071 by winding or coiling
• CPC Class Codes: Y10T 29/49073 by assembling coil and core
• CPC Class Codes: Y10T 29/49075 including permanent magnet or core

Abstract

A method of manufacturing an inductor for a microelectronic device comprises providing a substrate (610), forming a first plurality of inductor windings (111, 211, 411, 620, 2030) over the substrate, forming a magnetic inductor core (112, 212, 412, 810) over the first plurality of inductor windings, and forming a second plurality of inductor windings (113, 213, 413, 1010) over the magnetic inductor core. In another embodiment, the method comprises forming the inductor on a sacrificial substrate (1610) such that the inductor can subsequently be mounted onto a carrier tape (1810). In yet another embodiment, a method of manufacturing a substrate for a microelectronic device comprises forming an inductor within a build-up layer (101, 102, 103, 104) of a substrate.

Claims

1. A method of manufacturing an inductor for a microelectronic device, the method comprising:

providing a substrate;

forming a first plurality of inductor windings over the substrate;

forming a magnetic inductor core over the first plurality of inductor windings; and

forming a second plurality of inductor windings over the magnetic inductor core.

2. The method of claim 1 wherein:

forming the first plurality of inductor windings comprises;

depositing a metallic seed layer on the substrate;

patterning the metallic seed layer in order to define a plating region on the metallic seed layer; and

plating an electrically conductive material onto the metallic seed layer such that the electrically conductive material is located only in the plating region.

3. The method of claim 1 wherein:

forming the magnetic inductor core comprises;

depositing a magnetic material;

patterning the magnetic material in order to define a core region; and

shaping the magnetic material such that it is confined to the core region.

4. The method of claim 3 wherein:

patterning the magnetic material comprises;

depositing a photoresist mask on the magnetic material; and

thermally treating the photoresist mask such that the photoresist mask assumes a rounded shape; and

shaping the magnetic material comprises;

conformally etching the magnetic material such that the magnetic material also assumes a rounded shape.

5. The method of claim 3 wherein:

patterning the magnetic material comprises;

depositing a photoresist mask on the magnetic material using an ink-jet spraying procedure to deposit the photoresist mask with a rounded shape; and

shaping the magnetic material comprises;

conformally etching the magnetic material such that the magnetic material also assumes a rounded shape.

6. The method of claim 1 wherein:

forming the magnetic inductor core comprises;

using an ink-jet spraying procedure to deposit a nano-composite ink over the first plurality of inductor windings; and

transforming the nano-composite ink into a magnetic material having a rounded shape.

7. The method of claim 1 wherein:

forming the second plurality of inductor windings comprises;

forming a metallic seed layer;

patterning the metallic seed layer in order to define a plating region on the metallic seed layer; and

plating an electrically conductive material onto the metallic seed layer such that the electrically conductive material is located only in the plating region.

8. The method of claim 1 further comprising:

depositing a first electrically insulating material between the first plurality of inductor windings and the magnetic inductor core; and

depositing a second electrically insulating material between the magnetic inductor core and the second plurality of inductor windings.

9. The method of claim 8 further comprising:

patterning the second electrically insulating material.

10. A method of manufacturing a substrate for a microelectronic device, the method comprising:

providing a build-up layer of the substrate, the build-up layer comprising an electrically insulating material;

forming a first plurality of inductor windings in the build-up layer;

forming a magnetic inductor core over the first plurality of inductor windings;

forming a second plurality of inductor windings over the magnetic inductor core; and

forming a top layer of the substrate over the build-up layer.

11. The method of claim 10 wherein:

the build-up layer is one of;

a first-level die-side build-up layer of the substrate; and

a second-level die-side build-up layer of the substrate.

12. The method of claim 10 wherein:

forming the first plurality of inductor windings comprises;

forming a first metallic seed layer in the build-up layer;

patterning the first metallic seed layer in order to define a first plating region on the first metallic seed layer; and

plating a first electrically conductive material onto the first metallic seed layer such that the first electrically conductive material is located only in the first plating region; and

forming the second plurality of inductor windings comprises;

forming a second metallic seed layer in the build-up layer over the first metallic seed layer;

patterning the second metallic seed layer in order to define a second plating region on the second metallic seed layer; and

plating a second electrically conductive material onto the second metallic seed layer such that the second electrically conductive material is located only in the second plating region.

13. The method of claim 12 wherein:

forming the magnetic inductor core comprises;

depositing a magnetic material;

patterning the magnetic material in order to define a core region; and

shaping the magnetic material such that it is confined to the core region.

14. The method of claim 12 wherein:

forming the magnetic inductor core comprises;

using an ink-jet spraying procedure to deposit a nano-composite ink over the first plurality of inductor windings; and

transforming the nano-composite ink into a magnetic material having a rounded shape.

15. A method of manufacturing an inductor for a microelectronic device, the method comprising:

providing a sacrificial substrate;

forming a first metallic seed layer on the sacrificial substrate;

patterning the first metallic seed layer in order to define a first plating region on the first metallic seed layer;

plating a first electrically conductive material onto the first metallic seed layer in order to form a first plurality of inductor windings in the first plating region;

forming a magnetic inductor core over the first plurality of inductor windings;

forming a second metallic seed layer over the magnetic inductor core;

patterning the second metallic seed layer in order to define a second plating region on the second metallic seed layer;

plating a second electrically conductive material onto the second metallic seed layer in order to form a second plurality of inductor windings in the second plating region;

removing at least portions of the first and second metallic seed layers in order to complete a formation of the inductor;

encapsulating the inductor in a mold compound;

separating the inductor from the sacrificial substrate; and

placing the inductor onto a carrier tape.

16. The method of claim 15 wherein:

forming the magnetic inductor core comprises;

depositing a magnetic material;

patterning the magnetic material in order to define a core region; and

shaping the magnetic material such that it is confined to the core region.

17. The method of claim 15 wherein:

forming the magnetic inductor core comprises;

using an ink-jet spraying procedure to deposit a nano-composite ink over the first plurality of inductor windings; and

transforming the nano-composite ink into a magnetic material having a rounded shape.