Thin film coil, method of manufacturing the same, coil structure, and method of manufacturing the same

• US 7,307,503 B2
• Filed: 06/21/2005
• Issued: 12/11/2007
• Est. Priority Date: 07/01/2004
• Status: Expired due to Fees

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: Kaji, Rina, Kamijima, Akifumi, Aoki, Susumu, Takeo, Kenji, Sato, Yoshikazu
• Primary Examiner(s): MAI, ANH T
• Application Number:
  US11/156,526
• Publication Number:
  US 20060001520A1
• Time in Patent Office: 903 Days
• Field of Search: 336/200, 336/223, 336/232
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• CPC Class Codes: H01F 2017/0093 Common mode choke coil
• CPC Class Codes: H01F 27/34 Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
• CPC Class Codes: H01F 41/041 Printed circuit coils apparatus or processes for manufacturing printed circuits in general H05K3/00
• CPC Class Codes: H01L 28/10 Inductors

Abstract

The present invention provides a coil structure capable of improving a differential transmission characteristic by reducing capacitance as much as possible. A common mode choke coil is constructed so that a section of each of two coil patterns constructing a thin film coil has an inverted trapezoid shape which is bilaterally asymmetrical. Because of the structural characteristic that the section of each of the two coil patterns has an inverted trapezoid shape which is bilaterally asymmetrical, the facing area of the two coil patterns contributing to capacitance is minimized. Thus, the capacitance of the thin film coil can be reduced as much as possible.

Claims

1. A thin film coil including a first coil pattern and a second coil pattern which are provided on a predetermined underlayer and turn spirally in parallel with each other around a predetermined center position,

wherein the first coil pattern and the second coil pattern exist separately and are provided on the same level,

each of a section of the first coil pattern and a section of the second coil pattern has a trapezoid shape having one side positioned on the side far from the underlayer and specifying two base angles as a longer one of a set of opposite sides which are parallel to each other and the other side positioned on the side close to the underlayer as a shorter one of the set of opposite sides,

wherein a shape of the section of the first coil pattern and a shape of the section of the second coil pattern match each other in an arbitrary turn position,

wherein a first inner-side base angle positioned on the side close to the center position and a first outer-side base angle positioned on the side far from the center position out of the two base angles are different from each other in the section of the first coil pattern, and

a second inner-side base angle positioned on the side close to the center position and a second outer-side base angle positioned on the side far from the center position out of the two base angles are different from each other in the section of the second coil pattern.

2. A thin film coil according to claim 1,

wherein the first outer-side base angle is larger than the first inner-side base angle in the section of the first coil pattern, and

the second outer-side base angle is larger than the second inner-side base angle in the section of the second coil pattern.

3. A thin film coil including a first coil pattern and a second coil pattern which are provided on a predetermined underlayer and turn spirally in parallel with each other around a predetermined center position,

wherein the first coil pattern and the second coil pattern exist separately and are provided on the same level, and

each of a section of the first coil pattern and a section of the second coil pattern has a trapezoid shape having one side positioned on the side far from the underlayer and specifying two base angles as a longer one of a set of opposite sides which are parallel to each other and the other side positioned on the side close to the underlayer as a shorter one of the set of opposite sides,

wherein a shape of the section of the first coil pattern and a shape of the section of the second coil pattern are different from each other in an arbitrary turn position,

wherein a first inner-side base angle positioned on the side close to the center position and a first outer-side base angle positioned on the side far from the center position out of the two base angles match each other in the section of the first coil pattern, and

wherein a second inner-side base angle positioned on the side close to the center position and a second outer-side base angle positioned on the side far from the center position out of the two base angles match each other in the section of the second coil pattern.

4. A coil structure in which a thin film coil is buried between two magnetic substrates via an insulating layer,

wherein the thin film includes a first coil pattern and a second coil pattern which are provided on a predetermined underlayer and turn spirally in parallel with each other around a predetermined center position,

the first coil pattern and the second coil pattern exist separately and are provided on the same level,

each of a section of the first coil pattern and a section of the second coil pattern has a trapezoid shape having one side positioned on the side far from the underlayer and specifying two base angles as a longer one of a set of opposite sides which are parallel to each other and the other side positioned on the side close to the underlayer as a shorter one of the set of opposite sides,

wherein a shape of the section of the first coil pattern and a shape of the section of the second coil pattern match each other in an arbitrary turn position,

wherein a first inner-side base angle positioned on the side close to the center position and a first outer-side base angle positioned on the side far from the center position out of the two base angles are different from each other in the section of the first coil pattern, and

a second inner-side base angle positioned on the side close to the center position and a second outer-side base angle positioned on the side far from the center position out of the two base angles are different from each other in the section of the second coil pattern.

5. A coil structure in which a thin film coil is buried between two magnetic substrates via an insulating layer,

wherein the thin film includes a first coil pattern and a second coil pattern which are provided on a predetermined underlayer and turn spirally in parallel with each other around a predetermined center position,

the first coil pattern and the second coil pattern exist separately and are provided on the same level, and

each of a section of the first coil pattern and a section of the second coil pattern has a trapezoid shape having one side positioned on the side far from the underlayer and specifying two base angles as a longer one of a set of opposite sides which are parallel to each other and the other side positioned on the side close to the underlayer as a shorter one of the set of opposite sides,

wherein a first inner-side base angle positioned on the side close to the center position and a first outer-side base angle positioned on the side far from the center position out of the two base angles match each other in the section of the first coil pattern,

wherein a second inner-side base angle positioned on the side close to the center position and a second outer-side base angle positioned on the side far from the center position out of the two base angles match each other in the section of the second coil pattern, and

wherein a shape of the section of the first coil pattern and a shape of the section of the second coil pattern are different from each other in an arbitrary turn position.