JPH11307344A - Stacked inductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate directivity at the time of mounting a stacked inductor and to prevent a Q factor from being deteriorated, by satisfying a specified formula when the length of an element body is set to L1 and the length of one of a pair of drawing parts is set to L5. SOLUTION: A coil part 4 is buried in an element body. The winding axis Z of the coil part 4 and the electrodes 2 and 3 of the element body are constituted to cross one another. Drawing parts 5 and 6 are electrically connected to both ends of the coil part 4. When the length of the element body is set to L1 and the lengths of the drawing parts 5 and 6 to be L5, the formula of L5÷L1<=0.15 is satisfied. When the length of the element body is set to L1, height to L2 and width to L3, the conditions of 0.5 mm<=L1<=1.7 mm, 0.2 mm<=L2<=0.9 mm and 0.2 mm<=L3<=0.9 mm are satisfied. Thus, effect free of directivity and large Q value is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer inductor used for electronic equipment having a high-frequency circuit and the like.

[0002]

2. Description of the Related Art At present, inductors used in high-frequency circuits and the like include: (1) a laminated inductor in which a coil is formed using a laminated pattern; and (2) a conductive film formed on an insulator or a magnetic material. Chip inductors in which spiral grooves are formed in a conductive film (3) Inductors in which a winding is wound around a core are generally used.

[0003] With the downsizing of electronic devices, downsizing and high characteristics of inductors have been demanded, and various improvements have been made.

[0004] In particular, attention has been paid to a multilayer inductor which can manufacture a large number of elements at one time and is stable to some extent in characteristics. As a known example, Japanese Patent Application Laid-Open No. 9-186
No. 017 is known.

[0005]

However, in the above-described configuration, there is a problem that the directionality exists at the time of mounting and the characteristics change depending on the mounting method. Examples of the element having no directivity include elements having the shapes described in (2) and (3) above, but these elements are disadvantageous in terms of productivity and cost as described above.

An object of the present invention is to solve the above-mentioned conventional problems and to provide a laminated inductor having no directivity.

Another object is to provide a laminated inductor having a large Q value.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a laminated inductor in which a winding axis of a coil portion and an electrode intersect, wherein the length of the element body is L1, and the length of one of a pair of lead portions is one. When the length is L5, L5 ÷ L1 ≦ 0.15.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 includes an element body, a coil part embedded in the element body, a pair of lead-out parts electrically connected to the coil part, and the element body. A laminated inductor comprising a pair of electrodes provided on the top and electrically connected to the lead portion, wherein the winding axis of the coil portion intersects with the electrode, wherein the length of the element body is L1; By setting L5 ÷ L1 ≦ 0.15 when one of the pair of lead portions has a length of L5, it is possible to eliminate the directionality when mounting the multilayer inductor, and
Value deterioration can be prevented.

According to the second aspect of the present invention, by setting L5ＬL1 ≦ 0.10 in the first aspect, deterioration of the Q value can be further suppressed.

According to the third aspect of the present invention, by setting L5 ÷ L1 ≦ 0.05 in the first aspect, the Q value hardly deteriorates.

According to a fourth aspect of the present invention, in the first to third aspects, the element body has a columnar shape, electrodes are formed at both end portions and side surfaces of the element body, and the length of the electrode on the side surface portion is set. Is L4, L4 ÷ L1 ≦ 0.25
By doing so, the mountability can be improved, and the mounting density on the circuit board can be improved.

According to a fifth aspect of the present invention, in the first to fourth aspects, the lead-out portion is provided, and the lead-out portion is stepped down from the surface of the element body to form a recess, and the electrode enters the recess. As a result, it is possible to improve the bonding strength between the electrode and the lead portion, and to obtain good conduction.

According to a sixth aspect of the present invention, in accordance with the first to fourth aspects, the lead-out portion is provided, and the lead-out portion is protruded from the surface of the element body and is brought into contact with the electrode. And good conduction can be obtained.

According to a seventh aspect of the present invention, in the first to sixth aspects, the number of sheets is adjusted by forming a coil portion by laminating a laminated sheet having a conductive layer formed on the sheet. Can be changed, so that the inductance value can be easily changed.

According to an eighth aspect of the present invention, in the first to seventh aspects, the element body is formed into a prismatic shape, and the corners of the element body are chamfered, thereby suppressing the occurrence of burrs and cracks in the element body. You can do it.

According to a ninth aspect of the present invention, the generation of burrs and cracks in the element body can be reliably suppressed by setting the chamfer to 0.03 mm or more.

According to a tenth aspect of the present invention, in the first to ninth aspects, when the length L1, height L2, and width L3 of the element body 1 are set to 0.5 mm ≦ L1 ≦ 1.7 mm 0.2 mm ≦ L2 By setting ≦ 0.9 mm 0.2 mm ≦ L3 ≦ 0.9 mm, it is possible to reduce the size and strength of the multilayer inductor to some extent.

Hereinafter, embodiments of the present invention will be described. FIG. 1 is a perspective view showing a laminated inductor according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an element body, in which a coil portion (to be described later) is embedded. Electrodes 2 and 3 are provided at both ends of the element body 1, respectively. The electrodes 2 and 3 are provided on the end surfaces 1a and 1b and on a part of the side surface 1c, respectively.

It is advantageous for miniaturization, element strength, and the like to satisfy the following conditions in which the length L1, height L2, and width L3 of the element body 1 are set.

0.5 mm ≦ L 1 ≦ 1.7 mm 0.2 mm ≦ L 2 ≦ 0.9 mm 0.2 mm ≦ L 3 ≦ 0.9 mm By defining the size of the element body 1 as described above,
Even when the elements are mounted on a circuit board or the like, the mounting area on the circuit board can be reduced, and the size of the circuit board and the size and thickness of an electronic device on which the circuit board is mounted can be reduced.

Further, by defining the size as described above, the number of turns of the coil portion can be secured to some extent, and the inductance value and the like can be matched to the characteristics of the circuit.

A feature of the multilayer inductor element configured as described above is that the axis of the coil portion embedded in the element body 1 intersects the end faces 1a and 1b of the element body 1 (particularly preferably, the axis Z). And the end faces 1a and 1b intersect substantially perpendicularly). With such a configuration, even if any one of the four side surfaces 1c is brought into contact with or opposed to the circuit board, the change in the characteristics of the multilayer inductor becomes extremely small, and the directionality of the multilayer inductor can be eliminated. The performance is improved.

In this embodiment, since the element body 1 is formed in a prismatic shape and L2 = L3, the mountability is further improved. May be a prism having a regular polygonal cross section.

The corners of the element body (side surface 1c and side surface 1c)
, Etc., or where the side surfaces intersect with the end faces 1a, 1b)
By performing chamfering, chipping and cracking of the element body 1 can be prevented. The specific degree of chamfering is preferably 0.03 mm or more. If the chamfering is smaller than 0.03 mm, burrs and the like are likely to occur at corners, and chipping of the element body 1 and the like occur.

Further, it is preferable that the protruding length L4 of the portion protruding from the side surface 1c of each of the electrodes 2 and 3 is L4 ÷ L1 ≦ 0.25 based on the length L1 of the element body 1. When L4 ÷ L1 is larger than 0.25, when the element body 1 is mounted on a circuit board, a bonding material such as solder largely protrudes to the side of the element body 1, and the mounting density can be improved. Can not.

Next, the coil section will be described. FIG. 2 is a sectional view showing the laminated inductor according to one embodiment of the present invention.

In FIG. 2, reference numeral 4 denotes a coil portion, and the coil portion 4 is buried in the element body 1. As described above, the winding axis Z of the coil portion 4 and the end faces 1a and 1b (or the electrodes 2 and 3) of the element body 1 are configured to intersect (particularly preferably to intersect substantially vertically). Further, lead portions 5 and 6 are electrically connected to both ends of the coil portion 4, respectively, and the lead portions 5 and 6 are respectively connected to the electrodes 2 and 3. The coil unit 4 is configured by laminating sheets as shown in FIG.
In FIG. 3, reference numerals 7 to 10 denote laminated sheets, and laminated sheets 7 to 10 are basically made of a dielectric material, a magnetic material,
Conductive layers 7a to 10a are formed by patterning a conductive material such as a conductive metal such as copper, silver or gold or a conductive alloy on a sheet made of an insulating material or the like.

More specifically, the laminated sheets 7 to 10
The number of windings is determined by the number of the laminated sheets 8 and 9 alternately laminated. For example, laminated sheet 8
The laminated sheet 9 is stacked thereon such that the conductive layers 8a and 9a are not directly opposed. In order to conduct the conductive layer 8a and the conductive layer 9a, the point 8c and the point 9c are electrically connected. As a connection method at this time, for example, the point 9c of the laminated sheet 9 is extended to the back surface (point 8c of the conductive layer 8).
c is exposed), a conductive member is provided in the through hole, and points 8c and 9c are provided.
Are electrically connected. In this manner, one turn of the coil unit 4 is configured by stacking the laminated sheet 8 and the laminated sheet 9,
The number of turns of the coil unit 4 is adjusted by how many sets of the two laminated sheets 8 and 9 are stacked.
At both ends of the coil portion 4, laminated sheets 7 and 10 are provided, respectively, and points 7b and 10b are electrically connected to one of the laminated sheets 8 and 9 respectively.
c and 10c are connected to one of the drawers 5 and 6.

Further, the length L5 of the drawers 5, 6 shown in FIG.
Is based on the length of the element body 1 and 0 <L5 ÷ L1 ≦ 0.
It is preferable to configure so as to satisfy the condition of 15 (preferably 0.1, more preferably 0.05). By satisfying this condition, the Q value of the multilayer inductor can be improved. As shown in FIG.
If it is 15 or less, a sufficient Q value as a laminated inductor can be obtained, and if it is 0.1 or less, a very high Q value can be obtained because the deterioration of the Q value is within 10%. If it is 0.05 or less, almost no deterioration of the Q value occurs. A shown in FIG. 4 indicates that L1 = 1.6 mm, L
2 = L3 = 0.8 mm for a multilayer inductor, B
Is the case of a laminated inductor in which L1 = 1.0 mm and L2 = L3 = 0.5 mm. There is also a case where L5 ÷ L1 is 0, and in this case, there is an embodiment in which the drawers 5 and 6 do not exist. In this case, the electrodes 2 and 3 are directly formed on the exposed laminated sheets with the laminated sheets 7 to 10 exposed on the end surfaces of the element body 1.

Next, the drawers 5, 6 will be described. FIG.
As shown in FIG. 5, the lead portions 5 and 6 are formed by laminating one or a plurality of laminated sheets in which the conductive layer 11 is sandwiched between members made of an insulating material or the like.

As shown in FIG. 6, as the structure of the lead-out portions 5, 6, a through hole 12 is formed in one sheet or a laminated body in which a plurality of sheets are stacked, and a conductive material is embedded in the through hole 12. Alternatively, a method of forming a film of a conductive material on the inner wall in the through hole 12 is considered. The through holes 12 are formed by laser processing or the like.

Next, the relationship between the extraction portions 5 and 6 and the electrodes 2 and 3 will be described. As shown in FIG. 7, the extraction portions 5, 6 are provided with portions depressed from the end surfaces of the element body 1, and the electrodes 2, 3 are inserted into the depressions. To increase the area of joint with electrodes 2, 6
3, the contact area between the electrodes 2, 3 and the extraction portions 5, 6 can be increased, so that the conduction between the electrodes 2, 3 and the extraction portions 5, 6 is good. Can be prevented from deteriorating characteristics (the above structure is
5 and 6 (structure in which conductive material is emphasized in through hole 12)
Corresponding to the structure shown).

As shown in FIG. 8, when the lead portions 5 and 6 are formed by forming a conductive film on the inner wall of the through hole 12, a part of the electrodes 2 and 3 is formed in the through hole 12. By entering, the bonding strength and good conduction of the electrodes 2 and 3 can be obtained in the same manner as described above.
Corresponding to the structure shown).

Further, as shown in FIG. 9, by forming the lead-out portions 5 and 6 so as to protrude from the end face of the element body 1, it is possible to obtain the bonding strength and the good conduction as described above (the above-mentioned structure has , FIG. 5 and FIG. 6 (corresponding to the structure shown in FIG. 6 (the structure in which the conductive material is emphasized in the through hole 12)).

[0037]

According to the present invention, there is provided a laminated inductor in which a winding axis of a coil portion and an electrode intersect with each other.
When L5 ÷ L1 ≦ 0.15 when the length of one of the pair of drawers is L5, excellent effects such as no directivity and a large Q value are obtained. Can be done.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a laminated inductor according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a multilayer inductor according to an embodiment of the present invention.

FIG. 3 is a plan view showing a laminated sheet constituting the laminated inductor according to one embodiment of the present invention.

FIG. 4 is a graph showing a relationship between L5 ÷ L1 and a Q value of the laminated inductor according to one embodiment of the present invention.

FIG. 5 is a diagram showing a lead portion of the multilayer inductor according to the embodiment of the present invention;

FIG. 6 is a diagram showing another lead portion of the multilayer inductor according to the embodiment of the present invention;

FIG. 7 is a partial cross-sectional view showing a laminated inductor according to an embodiment of the present invention.

FIG. 8 is a partial cross-sectional view showing a laminated inductor according to one embodiment of the present invention.

FIG. 9 is a partial cross-sectional view showing a laminated inductor according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Element body 1a, 1b End surface 1c Side surface 2, 3 Electrode 4 Coil part 5, 6 Lead-out part 7, 8, 9, 10 Laminated sheet 7a, 8a, 9a, 10a Conductive layer 11 Conductive film

Claims (10)

[Claims] An element body, a coil part embedded in the element body, a pair of lead-out parts embedded in the element body and electrically connected to the coil part, and provided on the element body. And a pair of electrodes electrically connected to the extraction portion,
A laminated inductor in which the winding axis of the coil portion and the electrode intersect, wherein the length of the element body is L1, and the length of one of the pair of lead portions is L5, where L5 ÷ L1 ≦
A multilayer inductor, characterized in that the inductor is 0.15. 2. The multilayer inductor according to claim 1, wherein L5 ÷ L1 ≦ 0.10. 3. The multilayer inductor according to claim 1, wherein L5 ÷ L1 ≦ 0.05. 4. An element body having a columnar shape, electrodes formed on both end portions and side faces of the element body, and when the length of the electrode on the side face section is L4, L4 ÷ L1 ≦
4. The method according to claim 1, wherein the value is 0.25.
The multilayer inductor according to any one of the preceding claims. 5. The semiconductor device according to claim 1, wherein a lead portion is provided, and the lead portion is stepped down from the surface of the element body to form a recess, and an electrode is inserted into the recess. The multilayer inductor according to any one of the preceding claims. 6. The multilayer inductor according to claim 1, wherein a lead portion is provided, and the lead portion projects from the surface of the element body and comes into contact with an electrode. 7. A coil part is formed by laminating a laminated sheet having a conductive layer formed on a sheet.
6. The multilayer inductor according to any one of 6. 8. The device according to claim 1, wherein the element body has a prismatic shape, and a corner of the element body is chamfered.
The multilayer inductor according to any one of the preceding claims. 9. The multilayer inductor according to claim 8, wherein the chamfer is 0.03 mm or more. 10. The element body 1 has a length L1, a height L2, and a width L3.
The laminated inductor according to any one of claims 1 to 9, wherein 0.5 mm ≤ L1 ≤ 1.7 mm 0.2 mm ≤ L2 ≤ 0.9 mm 0.2 mm ≤ L3 ≤ 0.9 mm .