Method of fabricating an electromagnetic component

• US 9,009,951 B2
• Filed: 04/23/2013
• Issued: 04/21/2015
• Est. Priority Date: 04/24/2012
• Status: Active Grant

• Current Assignee: Cyntec Co. Ltd. (Delta Electronics Incorporated)
• Original Assignee: Cyntec Co. Ltd. (Delta Electronics Incorporated)
• Inventors: Chang, Wei-Chien, Chiang, Lang-Yi, Wu, Tsung-Chan, Wu, Chia-Chi, Yeh, Jih-Hsu
• Primary Examiner(s): Kim, Paul D
• Application Number:
  US13/868,993
• Publication Number:
  US 20130335186A1
• Time in Patent Office: 728 Days
• Field of Search: 296/021, 296/04, 296/06, 296/07, 336/199, 336/200, 336/205, 336/207, 336/208
• US Class Current: 29/607
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 2027/2809 on stacked layers
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 27/292 Surface mounted devices
• CPC Class Codes: H01F 41/04 for manufacturing coils coils for transformer or inductances H01F27/28
• CPC Class Codes: H01F 5/003 Printed circuit coils
• CPC Class Codes: H01F 5/02 wound on non-magnetic supports, e.g. formers
• CPC Class Codes: Y10T 29/49002 Electrical device making
• 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

An electromagnetic component includes a coil portion with a multi-layer stack structure, a molded body encapsulating the coil portion, and two electrodes respectively coupled to two terminals of the coil portion. The coil portion is fabricated using plating, laminating and/or pressing manufacturing techniques.

Claims

1. A method of fabricating an electromagnetic component comprising:

forming a coil portion having a multi-layer stack structure wherein the step of forming the coil portion comprises;

providing a substrate;

forming a first patterned photoresist layer on the substrate, the first patterned photoresist layer comprising an opening;

filling the opening with plated copper, thereby forming a first conductive trace;

removing the first patterned photoresist layer;

covering the first conductive trace with a dielectric layer having thereon a via hole;

plating a copper layer over the dielectric layer, wherein the copper layer fills the via hole;

forming a second patterned photoresist layer on the copper layer; and

etching the copper layer not covered by the second patterned photoresist layer, thereby forming a second conductive trace stacked on the first conductive trace, wherein the first and second conductive traces constitute a winding of the coil portion;

forming a molded body to encapsulate the coil portion, wherein the molded body comprises a magnetic material; and

forming two electrodes to electrically connected to two terminals of the coil portion respectively.

2. The method of fabricating an electromagnetic component according to claim 1 wherein the copper layer not covered by the second patterned photoresist layer is etched using wet etching methods.

3. The method of fabricating an electromagnetic component according to claim 1 wherein the substrate is a copper clad laminate (CCL) substrate.

4. The method of fabricating an electromagnetic component according to claim 1 wherein the second patterned photoresist layer is removed after the formation of the second conductive trace.

5. A method of fabricating an electromagnetic component comprising:

forming a coil portion having a multi-layer stack structure wherein the step of forming the coil portion comprises;

providing a substrate having thereon a first patterned conductive trace;

laminating the substrate with a build-up layer comprising an insulating layer and a copper foil;

forming a blind via in the build-up layer;

forming a plated copper layer on the build-up layer, wherein the plated copper layer fills into blind via to form a via electrically connecting the first conductive trace to the plated copper layer; and

patterning the plated copper layer and the copper foil thereby forming a second patterned conductive trace, wherein the first and second patterned conductive traces constitute a winding of the coil portion;

forming a molded body to encapsulate the coil portion, wherein the molded body comprises a magnetic material; and

forming two electrodes to electrically connected to two terminals of the coil portion respectively.

6. The method of fabricating an electromagnetic component according to claim 5, wherein after forming the second patterned conductive trace, the method further comprises:

removing a portion of the insulating layer and the substrate; and

forming an insulating protection layer.