Inductor element and method of manufacturing the same

• US 7,701,319 B2
• Filed: 09/12/2007
• Issued: 04/20/2010
• Est. Priority Date: 10/04/2006
• Status: Expired due to Fees

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Yamaguchi, Yoshinori, Kitamura, Kazumasa
• Primary Examiner(s): NGUYEN, TUYEN T
• Application Number:
  US11/853,860
• Publication Number:
  US 20080084265A1
• Time in Patent Office: 951 Days
• Field of Search: 336/65, 336/83, 336/200, 336206-208, 336232-234, 257/531
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 2017/002 Details of via holes for interconnecting the layers
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 41/0233 Manufacturing of magnetic circuits made from sheets magnetic cores made from sheets H01F27/245; soft magnetic alloys in the form of sheets H01F1/16
• CPC Class Codes: H01F 41/043 by thick film techniques
• CPC Class Codes: H01F 41/046 structurally combined with ferromagnetic material

Abstract

An inductor element comprises: a ceramic base member; and a coil composed of a conductor having a shape complementary to the ceramic base member. In the inductor element, a prescribed plural number of steps are formed on at least an inner wall surface of the ceramic base member facing to the coil in one direction.

Claims

1. An inductor element, comprising:

a ceramic base member; and

a coil composed of a conductor having a shape complementary to the ceramic base member,

wherein a predetermined number of steps are formed on at least an inner wall surface of the ceramic base member facing to the coil in one direction to form a cavity; and

wherein said coil substantially fills said cavity.

2. The inductor element according to claim 1, wherein a cutout is formed beneath of each of the steps in the same direction as a depth direction of each of the steps.

3. The inductor element according to claim 2, wherein the cutout has a dimension that is ⅕

to 1/200 of the maximum width of the ceramic base member in the same direction as a depth direction of the cutout.

4. The inductor element according to claim 2, wherein the cutout has a dimension of 2 to 20 μ

m.

5. The inductor element according to claim 3, wherein the cutout has a dimension of 2 to 20 μ

m.

6. The inductor element according to claim 1, wherein the inductor element has a square spiral shape.

7. The inductor element according to claim 1, wherein a ratio of a length of each of the predetermined number of steps in another direction different from the one direction in which the predetermined number of steps is formed to a length of each of the predetermined number of steps in the one direction is 0.4 to 1.0.

8. The inductor element according to claim 6, wherein a ratio of a length of each of the predetermined number of steps in another direction different from the one direction in which the predetermined number of steps is formed to a length of each of the predetermined number of steps in the one direction is 0.4 to 1.0.

9. The inductor element according to claim 1, wherein the ceramic base member is a magnetic ceramic base member composed of a magnetic member.