Inductor component and mounting structure of inductor component
An inductor component includes an element body; and a coil on the element body and wound into a spiral shape along an axis. The element body includes a substrate having first and second principal surfaces facing each other. The coil includes at least one first coil wiring on the first principal surface, at least one second coil wiring on the second principal surface, at least one first through wiring penetrating the substrate from the first principal surface to the second principal surface, and at least one second through wiring penetrating the substrate from the first principal surface to the second principal surface, and on a side opposite to the first through wiring with respect to the axis. The first coil wiring, the first through wiring, the second coil wiring, and the second through wiring are connected in sequence to constitute at least a part of the spiral shape.
1 . An inductor component comprising:
an element body including a substrate having a first principal surface and a second principal surface facing each other and an end surface extending in a direction orthogonal to the first principal surface; and
a coil on the element body and wound into a spiral shape along an axis,
wherein
the coil includes at least one first coil wiring on the first principal surface, at least one second coil wiring on the second principal surface, at least one first through wiring which penetrates the substrate from the first principal surface to the second principal surface, and at least one second through wiring which penetrates the substrate from the first principal surface to the second principal surface, and is on a side opposite to the first through wiring with respect to the axis,
the first coil wiring, the first through wiring, the second coil wiring, and the second through wiring are connected in this order to constitute at least a part of the spiral shape,
the at least one second coil wiring includes a both-end connecting coil wiring having a first end portion connected to the first through wiring and a second end portion connected to the second through wiring,
a portion of an outer surface of the both-end connecting coil wiring is exposed to at least an outside, the portion being located on a side opposite to the second principal surface,
an exposed surface of the outer surface of the both-end connecting coil wiring exposed to the outside contains a corrosion-resistant conductive material,
an insulating layer is disposed on the first principal surface,
an external electrode is disposed on the insulating layer such that the insulating layer is disposed between the external electrode and the first coil wiring in the direction orthogonal to the first principal surface, and
the external electrode is electrically connected to the coil via an end surface portion of the external electrode that is exposed to the outside on the end surface of the element body.
2 . The inductor component according to claim 1 , wherein
the corrosion-resistant conductive material is identical to a conductive material configuring an outer surface of the external electrode.
3 . The inductor component according to claim 2 , wherein
the external electrode is on the first principal surface of the substrate.
4 . The inductor component according to claim 1 , wherein
the corrosion-resistant conductive material is Au, Ti, a Ti alloy, Al, or an Al alloy.
5 . The inductor component according to claim 2 , wherein
the corrosion-resistant conductive material is Au, Ti, a Ti alloy, Al, or an Al alloy.
6 . The inductor component according to claim 1 , wherein
the first coil wiring includes one or more conductive layers,
the both-end connecting coil wiring includes two or more conductive layers, and
a number of the conductive layers of the both-end connecting coil wiring is larger than a number of the conductive layers of the first coil wiring.
7 . The inductor component according to claim 1 , wherein
no insulating layer is on the second coil wiring.
8 . The inductor component according to claim 1 , wherein
a conductive material as a main component of the first coil wiring and a conductive material as a main component of the second coil wiring are identical to a conductive material of at least one of the first through wiring and the second through wiring.
9 . The inductor component according to claim 1 , wherein
the first coil wiring is covered with the insulating layer.
10 . The inductor component according to claim 1 , wherein
the second coil wiring includes a main body including a conductive material identical to a conductive material of the first coil wiring, and a covering layer covering the main body and containing the corrosion-resistant conductive material, and
a line width of the main body is smaller than a line width of the first coil wiring.
11 . The inductor component according to claim 10 , wherein
at least a part of the covering layer covers outer surfaces of the main body on both sides in a width direction, and
W1>W21>W221+W222 is satisfied, where W 1 is a line width of the second coil wiring, W21 is the line width of the main body, W221 is a width of the covering layer covering the outer surface of the main body on one side in the width direction, and W222 is a width of the covering layer covering the outer surface of the main body on another side in the width direction.
12 . The inductor component according to claim 10 , wherein
T1>T21>2×T22 is satisfied, where T1 is a thickness of the second coil wiring, T21 is the thickness of the main body, and T22 is a thickness of the covering layer in a direction orthogonal to the second principal surface.
13 . The inductor component according to claim 1 , wherein
the second coil wiring includes a main body including a conductive material identical to the conductive material of the first coil wiring, and a covering layer covering the main body and containing the corrosion-resistant conductive material, and
a thickness of the main body is smaller than a thickness of the first coil wiring.
14 . The inductor component according to claim 1 , wherein
a plurality of the second coil wirings is present, and
an insulating layer is between the second coil wirings adjacent to each other.
15 . The inductor component according to claim 1 , wherein
a plurality of the first coil wirings, a plurality of the second coil wirings, a plurality of the first through wirings, and a plurality of the second through wirings are present,
a pitch between the first through wirings adjacent to each other is from 10 μm to 150 μm, and
a pitch between the second through wirings adjacent to each other is from 10 μm to 150 μm.
16 . A mounting structure of an inductor component, comprising:
a mounting substrate; and
the inductor component according to claim 1 mounted on a mounting surface of the mounting substrate,
wherein the axis of the coil is orthogonal to the mounting surface.
17 . The mounting structure of an inductor component according to claim 16 , wherein
the element body has a length, a width, and a height, and
the inductor component is arranged on the mounting surface in such a manner that a direction of a shortest dimension among the length, the width, and the height of the element body is orthogonal to the mounting surface.
18 . The mounting structure of an inductor component according to claim 16 , wherein
the element body has a length, a width, and a height, and
the inductor component is arranged on the mounting surface in such a manner that a direction of a longest dimension among the length, the width, and the height of the element body is orthogonal to the mounting surface.
19 . A mounting structure of an inductor component, comprising:
a mounting substrate; and
the inductor component according to claim 1 mounted on a mounting surface of the mounting substrate,
wherein the axis of the coil is parallel to the mounting surface.