JP2009094150A - Planar coil and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable the formation of a planar coil with a single layer pattern, and to enable a large reduction of the manufacturing cost without requiring a lamination process and via formation. <P>SOLUTION: An insulating film substrate 11 on one surface of which a first pattern 15 is formed in a first zone 13 and a second pattern 16 is formed in a second zone 14 is prepared, the film substrate 11 is folded along a bend line L, the first pattern 15 in the first zone 13 and the second pattern 16 in the second zone 14 are so opposed that they form a closed region in a plan view with the insulating film substrate 11 being interposed between them, and respective layers of the film substrate 11 are bonded together and fixed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a planar coil which is one of inductor components mounted on an electronic circuit and a method for manufacturing the same.

  At present, many inductor components are used as electronic components in electronic circuits, and planar coils are used for various applications as inductor components.

  An example of the configuration of a conventional planar coil is shown in FIGS. FIG. 2A is a plan view, and FIG. 2B is a cross-sectional view. A through-hole portion 2 is provided at substantially the center of the sheet-like element body 1, the coil 3 is disposed in the outer peripheral direction of the through-hole portion 2, the terminals 3 A and 3 B are disposed on the outermost peripheral portion of the coil 3, and the plane constituting the coil 3 Vias 4 are respectively formed in the element body 1 between the coils 3AA and 3BB, and a magnetic layer 5 is formed on the upper and lower surfaces of the element body 1 and the inner peripheral surface of the through-hole portion 2. The upper planar coil 3AA is spirally wound in a direction (inner circumferential direction) from the terminal 3A toward the through-hole portion 2, and the innermost circumferential portion of the planar coil 3AA and the innermost circumferential portion of the lower planar coil 3BB are wound. The planar coil 3BB is spirally wound in the direction toward the terminal 3B (periphery direction) by connecting via the via 4, and the coil 3 is configured (see, for example, Patent Document 1).

When manufacturing a planar coil configured as described above, the final product was obtained through a lamination process in which patterning was repeated over a plurality of layers on a substrate using photolithography technology and plating was performed on the inner surface of the through hole. .
JP 2007-227729 A

  However, the method for manufacturing a planar coil described in Patent Document 1 has a problem in that the planar coil is manufactured through a complicated stacking process using a multilayer substrate, so that there are many manufacturing processes and the cost is increased. .

  The present invention has been made in view of the above points, and provides a planar coil and a manufacturing method thereof that can form a planar coil with a single-layer pattern, can eliminate a lamination process and via formation, and can greatly reduce manufacturing costs. The purpose is to provide.

  The planar coil of the present invention includes a foldable and insulating film substrate and a conductor pattern formed on one surface of the film substrate, and the pattern formation region of the film substrate is folded at least once and two layers are formed. Each conductor pattern formed in each layer of the film substrate folded as described above is opposed to form a closed region in plan view.

  According to this configuration, since the planar coil in which the conductor pattern forms a closed region in a plan view can be easily manufactured by folding the film substrate, the laminating process and via formation can be eliminated, and the cost can be reduced.

  According to the present invention, in the planar coil, the film substrate is a part of the film substrate in which the conductor pattern is formed in a first area and a second area adjacent to each other across a linear boundary line. The film substrate is folded by sandwiching a third area different from the first and second areas between the conductor pattern of the first area and the conductor pattern of the second area. Features.

  According to this configuration, a third area that is a part of the film substrate and is different from the first and second areas is sandwiched between the conductor pattern of the first area and the conductor pattern of the second area. Therefore, the back surface of the first area and the second area (the surface on which the conductor pattern is not formed) can be folded so as to be exposed to the outside, so that the conductor pattern is not exposed to the outside.

  In the planar coil, the film substrate may be folded a plurality of times, and the conductive patterns formed on each layer of the film substrate folded into three or more layers may be opposed to each other so that a closed region is formed in plan view. Thereby, since the conductor pattern which comprises a planar coil is piled up in a multilayer, a magnetic force line density can be made high.

  In the planar coil, a plurality of closed regions by the conductor pattern may be connected in series in the film longitudinal direction.

  In the planar coil manufacturing method of the present invention, an insulating film substrate having a conductor pattern formed on one surface is prepared, and the pattern formation region of the film substrate is folded at least once and folded into two or more layers. Each conductive pattern formed on each layer of the film substrate is opposed to form a closed region in plan view, and the layers of the film substrate folded into two or more layers are joined and fixed.

  In the method for manufacturing a planar coil according to the present invention, the film substrate is formed such that the conductor pattern is formed in a first area and a second area adjacent to each other across a linear boundary line, and a part of the film substrate is formed. The film substrate is folded in a state where a third area different from the first and second areas is sandwiched between the conductor pattern of the first area and the conductor pattern of the second area. The conductor patterns in the first and second areas are insulated in the third area.

  According to the present invention, a planar coil can be formed with a single layer pattern, and a laminating process and via formation are not required, and the manufacturing cost can be greatly reduced.

  Hereinafter, a planar coil and a manufacturing method thereof according to an embodiment of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIGS. 1A and 1B are process diagrams showing a method of manufacturing a planar coil according to the first embodiment.
As shown in FIG. 1A, a single layer pattern 12 for forming a planar coil is formed on one film surface of a film substrate 11. The film substrate 11 is made of an insulating flexible film. As the material of the film substrate 11, a material having a heat fusion temperature lower than that of the metal material selected as the conductor material, elasticity that can be freely folded, and functioning as an insulating material is used. For example, polyimide, liquid crystal polymer, or polyethylene can be used. The film substrate 11 has a belt shape extending in one direction with a predetermined width. The single layer pattern 12 is a conductor formed of a metallic material such as silver or copper. As shown in FIG. 1A, a rectangular first that rises from the folding line L in the first area 13 with the center half as the folding line L and the upper half as the first area 13 and the lower half as the second area 14. Pattern 15 is formed, and a rectangular second pattern 16 rising from the folding line L is formed in the second area 14. The periods of the first pattern 15 and the second pattern 16 are shifted by a predetermined amount so as to partially overlap each other. Then, the tip ends of the leg portions 16a and 16b of the second pattern 16 positioned on the fold line L are extended in the opposing direction along the fold line L, and the two first first portions formed adjacent to each other upward. The corresponding ends of the leg portions 15a and 15b of the pattern 15 are connected. One end of the first pattern 15 formed on the leftmost side extends to the outer periphery of the sheet, and one end of the second pattern 16 formed on the rightmost side also extends to the outer periphery of the sheet. As described above, the single-layer pattern 12 forms a continuous conductor pattern by connecting the adjacent rising portions of the first pattern 15 and the second pattern 16.

Next, the procedure of the planar coil manufacturing method will be described.
A first pattern 15 is formed in the first area 13 of the film substrate 11 and a second pattern 16 is formed in the second area 14. That is, the single layer pattern 12 is formed on one surface of the film substrate 11. The first and second patterns 15 and 16 may be formed at the same time in the same process.

  Next, the pattern formation region of the film substrate 11 is folded as shown in FIG. The film substrate 11 is folded at the center along the folding line L so that the first pattern 15 and the second pattern 16 are on the outside, and the opposing surfaces are overlapped, as shown in FIG. The conductor forms a closed region.

  FIG. 2 shows the folding procedure. As shown in FIG. 2, a film substrate 11 having a single layer pattern 12 for forming a planar coil on one film surface is prepared ((A)). Next, the film substrate 11 is folded along the folding line L at the center and folded. As shown in FIG. 2, the back surface (non-pattern-formed surface side) of the second area 14 is folded and folded until the film surfaces come into contact with the back surface (non-pattern-formed surface) of the first area 13 ((B ) To (E)). As a result, the film substrate 11 region of the first area 13 and the second area 14 is sandwiched between the first pattern 15 and the second pattern 16. The folded film substrate 11 is pressed using a press device and heated in this state to heat-bond the film substrate 11 in the first area 13 and the second area 14. The heating temperature at this time is equal to or higher than the fusion temperature of the film substrate 11, but the first and second patterns 15 and 16 are adjusted to a temperature at which the film substrate 11 does not melt. The planar coil 20 shown in FIG. 1B was obtained by heating for a predetermined time and cooling after the back surfaces of the first zone 13 and the second zone 14 were completely heat-sealed. In addition, it can also join using an adhesive agent other than the heat sealing | fusion method.

  As shown in FIG. 1B, the planar coil 20 manufactured by the above manufacturing method has a shape in which the conductors (15, 16) continuously form the closed regions 21a to 21g in a plan view. The planar coil 20 in which the conductors (15, 16) form the closed regions 21a to 21g can have a large inductance value.

  As described above, according to the present embodiment, the single layer pattern 12 for forming the planar coil is formed on one film surface of the film substrate 11, and the film substrate 11 is bent to the side opposite to the single layer pattern 12 side. The first pattern 15 and the second pattern 16 can be disposed close to each other via the film substrate 11 (two layers) serving as an insulating material, and the closed regions 21a to 21g are formed in plan view. The planar coil 20 can be produced. Therefore, the conventionally required lamination process and via formation are not required, and the manufacturing cost can be greatly reduced.

(Second Embodiment)
The second embodiment has a structure in which a pattern constituting a planar coil is covered with a film substrate and incorporated.

  FIGS. 3A and 3B are process diagrams showing a method of manufacturing a planar coil according to the second embodiment. In addition, the same code | symbol is attached | subjected to the same part as each part of the planar coil shown to Fig.1 (a) (b), and duplication of description is avoided.

  As shown in FIG. 3A, the film substrate 11 forms a third area 17 on the first area 13. The third area 17 is set to have substantially the same width as the first and second areas 13 and 14.

  A first pattern 15 is formed in the first area 13 of the film substrate 11 and a second pattern 16 is formed in the second area 14. That is, the single layer pattern 12 is formed on one surface of the film substrate 11.

  Next, the film substrate 11 is folded in the direction and position shown in FIG. The third area 17 is bent along the folding line L2 to the formation surface side of the first pattern 15 so that the film surface of the third area 17 covers the upper surface of the first pattern 15 ((A), (B)). As a result, the first pattern 15 is sandwiched between the film areas of the first area 13 and the third area 17.

  Next, the film substrate 11 is folded along the folding line L1 so that the second pattern 16 overlaps the back side of the third area 17 ((C), (D)). As a result, the third area 17 is arranged between the first pattern 15 and the second pattern 16, and the first pattern 15 and the second pattern 16 are moved from the outside to the first area 13 and the second pattern 16. It is in a state of being sandwiched between the areas 14. The film substrate 11 bent as described above is pressed using a pressing device and heated in this state to heat-melt the film substrate 11 in the first zone 13, the second zone 14, and the third zone 17. Put on. The planar coil 20 shown in FIG. 3 (b) was obtained by heating for a predetermined time and cooling after the back surfaces of the first zone 13 and the second zone 14 were completely heat-sealed.

  As described above, according to the present embodiment, the planar coil 20 having the coil conductor surface covered with the insulating film substrate 11 can be produced only by adding one folding process of the film substrate 11. It is possible to prevent the surface from being exposed to the outside.

(Third embodiment)
The third embodiment is an example in which a multilayer planar coil is easily created by folding a film substrate in a triple manner.

  FIGS. 5A and 5B are process diagrams showing a method of manufacturing a planar coil according to the third embodiment. The film substrate 11 is divided into a first area 31 to a fifth area 35, and a single layer pattern 30 is formed on the same film surface in the second area 32 to the fifth area 35. No pattern is formed in the first area 31. First to fourth patterns 36, 37, 38, 39 are formed in the second area 32 to the fifth area 35, respectively. In the second area 32, a rectangular first pattern 36 rising downward from the folding line L2 is continuously formed at a predetermined period. The first pattern 36 is open near the center on the folding line L2. In the third area 33, a second pattern 37 composed of connecting conductors 37a and 37b connecting the first pattern 36 and the third pattern 38 is formed. In the fourth area 34, a third pattern 38 having a rectangular shape is continuously formed in the same area as the first pattern 36. The third pattern 38 is open near the center on the third and fourth fold lines L3 and L4. In the third area 33, linear connecting conductors 37a, which connect the opening on the folding line L2 of the first pattern 36 and the opening on the third folding line L3 of the third pattern 38, respectively. 37b is formed in parallel. In the fifth area 35, a fourth pattern 39 having a rectangular shape rising from the fourth fold line L4 is continuously formed with a period slightly shifted from the third pattern 38 in the film longitudinal direction. In the fourth pattern 39, one leg 39a is connected to one end 38a of the opening of the third pattern 38 on the fourth fold line L4, and the other leg 39b is adjacent to the opening of the third pattern 38. Connected to one end 38a. Thus, the single layer pattern 30 formed on one surface of the film substrate 11 is formed as a continuous pattern, and when folded three times, the conductor forms closed regions 30a to 30h in plan view. The first to fourth patterns 36, 37, 38, and 39 are arranged as described above.

The method of manufacturing the planar coil 30 configured as described above is according to the following procedure.
First, the single layer pattern 30 is formed in the second to fifth areas 32 to 35 of the film substrate 11. As described above, the single-layer pattern 30 includes the first to fourth patterns 36, 37, 38, and 39 in which the conductors form the closed regions 30a to 30h in plan view when the film substrate 11 is folded three times. Is done.

  Next, the first section 31 is bent toward the pattern forming surface along the first fold line L1 so as to cover the first pattern 36. Next, the film substrate 11 is folded in the same direction as the first folding direction along the second folding line L2, and the back surface of the first area 31 is overlapped with the pattern forming surface of the third area 33. Next, the film substrate 11 is folded in the same direction as the second folding direction at the third folding line L3 so that the back surface of the second area 32 overlaps the pattern forming surface of the fourth area 34. Next, the film substrate 11 is folded in the same direction as the third folding direction along the fourth folding line L4 so that the back surface of the third area 33 overlaps the pattern forming surface of the fifth area 35. As a result, the first area 31 is disposed between the first pattern 36 and the second pattern 37, and the first pattern 36 and the third pattern 38 pass through the film substrate 11 in the second area 32. Oppositely arranged at the same position across. Further, the fourth pattern 39 is disposed oppositely at the same position across the film substrate 11 in the third area 33. Therefore, the first to fourth patterns 36, 37, 38, and 39 are stacked with the film substrate 11 interposed therebetween. The film substrate 11 bent as described above is pressed using a press device and heated in this state to heat-bond the film substrate 11. It cooled after predetermined time progress and the planar coil shown in FIG.5 (b) was obtained.

  As described above, according to the present embodiment, the single-layer pattern 30 is formed in the second to fifth areas 32 to 35 of the film substrate 11, and the film substrate 11 is folded three times to thereby form the closed regions 30 a to 30. The conductor forming 30h can have a double structure, and the magnetic flux density can be increased.

Next, modifications of the shape of the planar coil will be described.
FIGS. 6A and 6B are views showing a method for manufacturing a planar coil in which the closed region of the conductor forms a polygon that is rounder than a quadrangle. The film substrate 11 is vertically divided from the center into a first area 41 and a second area 42, a first pattern 43 is formed in the first area 41, and a second pattern 44 is formed in the second area 42. Form. In the first pattern 43, each corner of the rectangular pattern is dropped, and the end portions 43a and 43b on the folding line L side are slightly bent inward. The second pattern 44 is formed so as to be shifted in the film longitudinal direction so as to straddle the adjacent first pattern 43. The end portions 44 a and 44 b on the folding line L side of the second pattern 44 are connected to the corresponding end portions 43 b and 43 a of the two corresponding first patterns 43.

  The film substrate 11 is folded along the folding line L so that the back surfaces of the first area 41 and the second area 42 overlap each other. The first zone 41 and the second zone 42 are heat-sealed by heating with a press device. As a result, as shown in FIG. 6B, the closed regions 45a to 45g made of a conductor have a shape close to a circle. The film substrate 11 bent as described above is pressed using a press device and heated in this state to heat-bond the film substrate 11. It cooled after progress for the predetermined time, and the planar coil shown in FIG.6 (b) was obtained.

  FIGS. 7A and 7B are views showing a method for manufacturing a planar coil in which the size of the closed region formed by the conductor is reduced. The height of the first pattern 46 formed in the first area 41 (the dimension in the direction perpendicular to the film longitudinal direction) is half the height of the second pattern 47 formed in the second area 42.

  The film substrate 11 is folded along the folding line L so that the back surfaces of the first area 41 and the second area 42 overlap each other. The first zone 41 and the second zone 42 are heat-sealed by heating with a press device. As a result, as shown in FIG. 7B, closed coils 48a to 48g made of a conductor form a planar coil having a height about half that of the closed regions 21a to 21g shown in FIG. 1B. The film substrate 11 bent as described above is pressed using a press device and heated in this state to heat-bond the film substrate 11. It cooled after progress for the predetermined time, and the planar coil shown in FIG.7 (b) was obtained.

FIGS. 8A and 8B are diagrams showing a method for manufacturing a planar coil in which a closed region formed by a conductor has a semicircular shape.
As shown in FIG. 8A, an oval first pattern 52 in which straight portions on the folding line L are opened is formed at predetermined intervals in the first area 41 of the lower half of the film substrate 11. Further, a rectangular second pattern 51 having one side on the folding line L opened in the second area 42 of the upper half of the film substrate 11 is shifted by a substantially half cycle with respect to the lower first pattern 52 and predetermined. Form at intervals.

  Next, the film substrate 11 is folded so that the back surfaces of the first and second areas 41 and 42 overlap with each other with the fold line L as the center, thereby forming a rectangular second pattern as shown in FIG. 51 and the curved portions of the oval first pattern 52 overlap to form a plurality of planar coils in which semicircular closed regions 53a to 53g continue at a predetermined interval. The film substrate 11 bent as described above is pressed using a press device and heated in this state to heat-bond the film substrate 11. It cooled after predetermined time progress and the planar coil shown in FIG.8 (b) was obtained.

  9A and 9B illustrate a method for manufacturing a planar coil in which a closed region formed by a conductor forms a perfect circle. As shown in FIG. 9A, an oval conductor pattern 55 in which straight portions on the folding line L are opened is formed at predetermined intervals in the second area 42 of the upper half of the film substrate 11. In addition, the oval conductor pattern 54 in which the straight line portion on the folding line L is opened in the first area 41 in the lower half of the film substrate 11 is shifted from the second pattern 55 on the upper side by a substantially half cycle to a predetermined interval. Form with.

  Next, by folding the film substrate 11 so that the back surfaces of the first and second areas 41 and 42 overlap with each other about the fold line L, as shown in FIG. A plurality of planar coils in which the curved portions of the conductor pattern overlap and circular closed regions 56a to 56d continue at a predetermined interval are formed. The film substrate 11 bent as described above is pressed using a press device and heated in this state to heat-bond the film substrate 11. It cooled after progress for the predetermined time, and the planar coil shown in FIG.9 (b) was obtained.

  The present invention can be applied to inductor components of electronic circuits and small antenna devices.

(A) The top view which shows the state before bending in the manufacturing method of the planar coil which concerns on 1st Embodiment, (b) The top view which shows the state after bending Explanatory drawing which shows the bending order in the planar coil manufacturing method of 1st Embodiment (A) The top view which shows the state before bending in the manufacturing method of the planar coil which concerns on 2nd Embodiment, (b) The top view which shows the state after bending Explanatory drawing which shows the bending order in the planar coil manufacturing method of 2nd Embodiment (A) The top view which shows the state before bending in the manufacturing method of the planar coil which concerns on 3rd Embodiment, (b) The top view which shows the state after bending (A) The top view which shows the state before bending in the manufacturing method of the planar coil which concerns on the modification which forms a polygonal closed region, (b) The top view which shows the state after bending (A) The top view which shows the state before bending in the manufacturing method of the planar coil which concerns on the modification which forms the closed region of small size, (b) The top view which shows the state after bending (A) The top view which shows the state before bending in the manufacturing method of a semicircle high opening planar coil, (b) The top view which shows the state after bending (A) The top view which shows the state before bending in the manufacturing method of a circular high opening planar coil, (b) The top view which shows the state after bending (A) Plan view of a conventional planar coil, (b) Cross-sectional view of a conventional planar coil

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Film substrate 12, 30 ... Single layer pattern 13, 31, 41 ... 1st area 14, 32, 42 ... 2nd area 15, 36, 43, 46, 52, 54 ... 1st pattern 16, 37 , 44, 47, 51, 55 ... second pattern 17 ... third zone 20 ... planar coil 21a-21g, 30a-30h, 45a-45g, 48a-48g, 53a-53g, 56a-56d ... closed region 33 3rd area 34 ... 4th area 35 ... 5th area 38 ... 3rd pattern 39 ... 4th pattern 40 ... 5th pattern

Claims (6)

A foldable and insulating film substrate, and a conductor pattern formed on one surface of the film substrate,
The pattern formation region of the film substrate is folded at least once, and each conductor pattern formed on each layer of the film substrate folded into two or more layers is opposed to form a closed region in plan view. Planar coil to do.   In the film substrate, the conductor pattern is formed in a first area and a second area adjacent to each other across a linear boundary line, and the film substrate is a part of the film substrate and includes the first and second areas. 2. The planar coil according to claim 1, wherein the film substrate is folded by sandwiching a different third area between the conductor pattern of the first area and the conductor pattern of the second area. .   The film substrate is folded a plurality of times, and the conductive patterns formed on each layer of the film substrate folded into three or more layers are opposed to each other so that a closed region is formed in a plan view. Item 3. The planar coil according to Item 2.   The planar coil according to any one of claims 1 to 3, wherein a plurality of closed regions by the conductor pattern are connected in series in the film longitudinal direction.   An insulating film substrate having a conductor pattern formed on one surface is prepared, and each conductor formed on each layer of the film substrate folded into at least two layers by folding the pattern formation region of the film substrate at least once A method for producing a planar coil, wherein a pattern is opposed so that a closed region is formed in a plan view, and each layer of a film substrate folded into two or more layers is joined and fixed. In the film substrate, the conductor pattern is formed in a first area and a second area adjacent to each other across a linear boundary line, and the film substrate is a part of the film substrate and includes the first and second areas. The film substrate is folded with a different third area sandwiched between the conductor pattern of the first area and the conductor pattern of the second area, and the conductor pattern of the first and second areas is folded. The method for manufacturing a planar coil according to claim 5, wherein the coil is insulated in the third area.

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