DE19835016B4 - Block-wise manufacturing of inductors with microtechniques - Google Patents

Abstract

method for the production of electrical components that act as an inductance with a conductive Layer include a volume, using spatial pre-patterned substrates (300; 310; 320; 330) having a plurality blanks (R1, R2, R3, R4, R5, R6, R7) in matrix arrangement therethrough characterized in that spatial pre-structured substrates (300; 310; 320; 330) by a plurality parallel sections (A-A, B-B) perpendicular to in a block (400; 410; 420; 430) arranged in parallel electrical conductor tracks (102; 112; 122) are produced.

Description

The The present invention relates to a process for the preparation of inductors from a benefit using microtechniques and a suitable one Coil design. At the inductances these are long coils or electrical ones made of such Components.

A conventional high-frequency coil and a conventional method for their preparation, for example, from DE 691 11 569 T2 known.

Become conventional inductive electrical components in classical wire winding technology over one Ceramic core made because of the design of a long Coil excellent electrical data especially in Hochfrezzbereich achieve. In doing so, the coil becomes mechanical winding technology realized with wire. Coils are in contrast to resistance and Capacitor elements volume-dependent Components, which is why the classic wire winding technique used is to achieve the appropriate electrical properties.

The Production of so-called long coils by means of conventional Wire winding technology, however, leaves no over the order of magnitude of 1 mm × 1 mm × 2 mm miniaturization. Through the serial production the coils by conventional Wire winding technology is also tedious and expensive to manufacture which leads to high production costs.

With ever smaller dimensions of the components, eg. B. for surface mounting technology, are therefore the limits of a serial production of coils in conventional Feinwerktechnik achieved, so that planar Coils were developed on ceramic substrates, which over the Use production in microtechnologies, such as planar thin-film and thick film technology also a cost advantage is achieved. planar However, coils are very much compared to three-dimensional coils much worse high frequency characteristics. The disadvantageous High frequency characteristics of planar coils are due to the increased capacity of the planar ones Design and by the adverse dielectric properties of the Substrates caused. Even conventional from planar elements composite multilayer coils connected to via elements are, have adverse parasitic Values and accordingly low grades.

It was therefore attempting to use pre-structured substrates for the production of "long coils", for example: lithographic techniques can be used, such as For example: in the article "Conformal Coating by Photoresist of Sharp Corners of Anisotropically Etched Trough-Holes in Silicon "in Transducers 97 Proceedings, 209-212 are described.

Under Use of such or similar lithographic techniques, a substrate is prestructured in such a way that that one Variety of similar trained coil elements on tightest Space in a plane arranged in matrix arrangement next to each other are.

The Applicants of the present invention therefore have a method of Production of non-planar, long coils in the benefits of microtechnology proposed in which prestructured substrates are used, in which hole connections between two substrate sides in a separate manner getting produced. A variety of pre-structured coil blanks is doing in batch processing formed to the finished coil. The coil blanks are on tightest Space in a plane next to each other and are after completion separated from each other. The formation of the hole connections between However, the two substrate sides is extremely difficult to achieve the required accuracy produced.

task The present development is therefore a simple and cost-effective Method of inductive basic components formed from a utility to provide, by means of a formation of hole connections between the two sides of the substrate can be avoided. there it should be three-dimensional inductors that are used for industrial Mass production are particularly suitable and the asked high Quality demands full satisfy.

The The above object is achieved according to the invention with the features of the characterizing Part of claim 1 solved. Advantageous versions result from the features of the subclaims and / or the following description. The invention will be described below with reference to exemplary embodiments, which are shown in schematic drawings. This shows:

1a , b and c show a first planar pre-structured substrate according to the invention;

2a and b, a full-surface metallization substrate;

3a and b a first according to the invention block consisting of a plurality of laminated pre-structured substrates of 1 and 2 ;

4a a plan view of a first inventive spatially prestructured substrate, cut from the block of 3 ;

4b an enlarged section 4a with a coil blank rotated by 90 ° according to the invention;

5a a second areal prestructured substrate according to the invention;

5b a modification of the second area prestructured substrate;

5c the second area prestructured substrate with tracks;

6a a passivation layer;

6b a full-surface metallization;

6c a second block according to the invention consisting of laminated prestructured substrates of 5 ;

7a a plan view of a second inventive spatially prestructured substrate, cut from a third block according to the invention, formed from the substrates of 5b ;

7b a rotated by 90 ° enlarged section of a coil blank of 7a ;

8a , b and c, a third planar pre-structured substrate according to the invention with via elements;

9a and b a fourth block according to the invention consisting of laminated prestructured substrates of 8th ;

10 a fifth block according to the invention consisting of laminated prestructured substrates of 1 ;

The above 1 - 10 are purely schematic explanatory diagrams for a better understanding of the description. In particular, they do not represent a true-to-scale enlargement of the actual dimensions and size ratios. For example, in the figures, the width B of the vertical conductor tracks 102 and 112 and the width of the tracks 104 and 113 opposite the distance G of the vertical conductor tracks 102 shown in a size ratio that does not have to correspond to the size ratio of G and B in the coil design and may differ significantly. This also applies to the thickness of the laminated substrates and to the thickness of the substrates cut from the laminated block. In addition, it will be understood that the invention is not limited to the number of substrates stacked one above the other in the block, as exemplified purely by way of example in the drawings, which may be varied as the number of coil turns per coil, depending on the coil design.

With the method according to the invention can be coils of in 4b produce advantageous shown dimensions:
Length (distance of the straight line CC): 0.1-10 mm, in particular 0.6-1 mm
Width (distance of the line DD): 0.05-5 mm, especially 0.3-0.7 mm
Depth (perpendicular to the paper plane): 0.05-5 mm, in particular 0.3-0.7 mm
Cross section: 0.0025-25 mm ² , in particular 0.25 mm ²
Distance of the conductor tracks G: 0.01-0.1 mm, in particular 0.02-0.04 mm
Cross section of the conductor tracks B: 0.01-0.1 mm, in particular 0.02 mm

Of the The present invention is based on the idea of a method to provide for the manufacture of electrical components, the as inductance with a conductive Layer include a volume, being spatially pre-structured substrates with a variety of blanks used in matrix arrangement be, and according to the invention, the spatially pre-structured Substrates by means of a plurality of parallel sections perpendicular to in a prestructured block arranged in parallel electrical Printed conductors are produced.

there It is particularly advantageous that the block of a variety laminated areal likewise pre-structured substrates is composed.

One inventive method for the production of inductors, with a conductive layer include a volume consists in particular of the following steps:

step 1: Production of the large number of planar prestructured Substrates with the plurality of parallel tracks;

step 2: Production of the three-dimensional invention Blocks by laminating a variety of areal prestructured Substrates one above the other;

Step 3: Production of the plurality of spatially pre-structured substrates according to the invention with a plurality of parallel vertical conductor tracks by cuts from the block perpendicular to the parallel tracks;

step 4: connection of the vertical tracks by means of and bottom of the spatially prestructured substrates in each case arranged in parallel conductor tracks, so that one Variety of coil blanks in a matrix arrangement formed side by side are.

step 5: Separation of the blanks by cuts at the boundaries of the blanks.

L:

Induktivität

N:

Windungszahl

l:

Länge der Spule

A:

Querschnitt

l:

Länge

In principle, coils of suitable quality are three-dimensional components, since the inductance of a coil is given by the following equation: L = μμ 0 (N / l) 2 × A × l (Equation 1)

L:

inductance

N:

number of turns

l:

Length of the coil

A:

cross-section

l:

length

In Equation 1) describes A × l the coil volume, and N / l the technically relevant size number of turns per length. From equation 1) it is apparent that the quality of the inductance of the enclosed coil volume and the number of turns is dependent. Therefore, it is desirable that this enclosed coil volume to be optimized cross-section which may advantageously be square or rectangular, and the turns as symmetrical as possible over the enclosed coil volumes are distributed so that a uniform Gangfortschritt the turns over all turns and trapped volume from the first to is reached to the second coil end.

The Distribution of the walking progress G can be distributed to one or more coil surfaces be, with the distribution on several coil surfaces at fixed Winding distance to reduced slope angles α of the conductor paths per coil side leads and so the angle-related narrowing of the effective path distance b '= (α × cosα) - b with a = path distance and b = line width reduced.

following be advantageous embodiments the invention in which also the above considerations for the dimensions considering the coils find detailed descriptions.

1 shows a surface prestructured substrate according to the invention 100 made of, for example, polyimide. Polyimide is particularly suitable for spatial structuring and has a dielectric constant which is suitable for volume filling in inductors. In the planar prestructured substrate 100 be on a surface of the substrate 100 initially advantageous parallel trenches 101 formed by means of, for example: laser structuring or molding, and then the parallel trenches filled with a conductive material, whereby a first inventively areal prestructured substrate 100 with parallel tracks 102 provided on a surface.

When Conductive material is advantageous copper in question.

The substrate 100 has in the passage progress of the coil has a thickness in the range of 20μm to 100μm, the parallel tracks a cross section of the order of 20μm × 20μm and a distance of 20μm.

It is clear that the tracks 102 also beneficial to the smooth surface of the substrate 100 Can be applied without the trenches 101 to structure whereby inversely those between the conductor tracks 102 filled in between spaces are filled:
2 shows the substrate according to the invention 200 , made of the same material as the substrate 100 , which, however, is metallized over its entire surface on one surface.

From the substrates 100 and 200 In each case a plurality of identical substrates are produced. 3 shows the block according to the invention 400 consisting of a plurality of superimposed pre-structured substrates 100 and 200 consists, according to the invention a predetermined number of substrates 100 between an upper and lower substrate 200 is arranged. From the block so formed 400 According to the invention along the section line AA and BB, a plurality of identical spatially structured substrates 300 with vertical tracks 102 for the coil turns and for the contact ends 202 cut the coil. The spatially structured substrate has a thickness of 250 .mu.m to 1000 .mu.m.

4a shows the top view of a section of the spatially prestructured substrate 300 with the two coil blanks R1 and R2, with their longitudinal axis in the slice direction S of the block 400 from which the substrate 300 was cut, are directed. The vertical tracks 102 are perpendicular to the substrate 300 formed continuously and on parallel lines D, D parallel to the direction of layering S at equal intervals corresponding to the thickness of the surface prestructured substrate 100 arranged. Perpendicular to the layering direction S, two vertical interconnects lying opposite one another have a spacing from the spacing of the parallel interconnects on the areally prestructured substrate 100 ent speaks. The so spatially pre-structured substrate 300 consists of a plurality of coil blanks R1, R2 arranged side by side in a matrix arrangement, which with their longitudinal axis parallel to the layer direction of the block 400 are aligned. By connecting the vertical tracks 102 on one side of the substrate 300 with to the cross section through the coil blanks R1, R2 parallel first planar conductor tracks 103 and on the other side of the substrate with conductor tracks arranged at an angle to the cross section through the coil blanks R1, R2 104 corresponding to the progress G of the coils and corresponding connections to the metallizations for the end face contacts 202 a plurality of coils arranged in a matrix arrangement on a surface are completed.

By means of vertical sections through the lines CC and DD or CC and D1-D1, a multiplicity of individual finished coils are obtained from the substrate according to the invention 300 cut out. 4b shows the rotated by 90 ° enlarged section of the coil blank R1. The cuts CC advantageously pass through the metallizations for the contact ends 202 , which are halved and form the contact ends of two adjacent coils. The cuts DD advantageously pass through the middle of two opposing rows of vertical tracks 102 , whereby a maximum number of coil yield from the substrate 300 is won. However, slices D1-D1 may also advantageously pass through the centerline of two adjacent opposing rows of vertical traces 102 go, since the coil windings are already isolated by the isolation on their cutting sides, and thus isolated at the interfaces and protected from corrosion.

5 shows the pre-structured areal substrate 110 according to a further advantageous embodiment of the present invention. The substrate 110 corresponds to the substrate 100 from 1 , with the difference that the trenches 111 and the parallel tracks 112 are arranged on both surfaces of the substrate at equal intervals parallel to each other. In the execution of 5a and c are the parallel trenches 111 and tracks 112 placed on the two surfaces exactly opposite each other while in the execution of 5b the parallel trenches 111 and tracks 112 are arranged offset in such a way that a conductor track 112 on the one surface of the substrate 110 exactly between two opposing tracks 112 on the other surface of the substrate 110 to come to rest. Due to the arrangement of 5b can be beneficial to a Passivierungszwischenschicht 210 be dispensed with and also the passage progress G are distributed to two opposite side walls of the bobbin.

6 shows a schematic representation of the front of a section of a three-dimensional block according to the invention 410 consisting of a predetermined number of superimposed substrates 110 the execution of 5a and c each consisting of an insulating layer between them 210 are separated from each other, and wherein the predetermined number of the laminated substrates 110 between an upper and lower full-surface metallization 212 is arranged for the contact ends of the coils. The insulating layer need not be the substrate thickness of the substrates 110 have and can be, for example: potting compound. According to the invention, the three-dimensional block 410 in the same way as from the block described above 400 a plurality of identical spatially structured substrates (not shown) by means of sections perpendicular to the parallel conductor tracks 112 provided, and from these spatially structured substrates as above 4 described by applying planar conductor tracks and singulation of the coils produced a plurality of coils.

7a shows a spatially structured substrate according to the invention 310 consisting of a block, not shown, of a plurality of superimposed areal prestructured substrates 110 from 5b is cut, wherein in each case a predetermined number of the substrates 110 between an upper and lower full-surface metallization 212 are laminated for the end faces of the coils. With suitable design of the tracks 112 and their distance can be, as in 7a is shown to be dispensed with an intermediate insulating layer. The structure of the spatially pre-structured substrate 310 corresponds to the structure of the spatially pre-structured substrate 300 from 4 with the difference that a vertical trace 112 a series along a straight line D parallel to the layer direction S arranged conductor tracks 112 in the middle between two perpendicular to the direction of layering S opposite conductor tracks 112 is arranged.

The coil blanks R3 and R4 of 7a and b correspond to the coil blanks R1 and R2 of FIG 4a and b and are corresponding to these on the top and bottom of the substrate 310 with planar tracks 113 and 114 provided the vertical tracks 112 with each other and with the metallizations for the contact surfaces 212 The coil blanks R3 and R4 are then separated along lines CC and DD or D1, D1 into individual coils. Unlike the substrate 300 from 4 are at the substrate 310 from 7 the planar tracks 113 and 114 on the top and bottom of the substrate 310 at an angle perpendicular to the coil cross-section corresponding to the progress G of the spool le arranged, which is advantageously distributed in this embodiment on two opposite coil surfaces.

8th shows a further pre-structured planar substrate according to the invention 120 with a variety of parallel tracks 122 at a predetermined distance on the one surface of the substrate 120 as a modification of the substrate 100 from 1 , 8a shows the substrate in perspective, and 8b and c show a top and bottom view. According to the invention are in the substrate 120 a predetermined number of the parallel tracks as via elements 123 formed continuously through the substrate depth, and so on the substrate 120 arranged that a predetermined number of conductor tracks 122 that the conductor tracks 102 from 1 correspond between two via elements 123 to come to rest.

9 shows the block according to the invention 420 , which consists of a multitude of laminar pre-structured substrates 120 consists. The block 420 corresponds to the block 400 from 3 , with the difference that the whole-surface metallizations 123 for the contact surfaces at the coil ends through the superimposed via elements 123 be formed and unlike the block 400 are arranged parallel to the layer direction S. Out of the block 420 will be similar to the block 400 along the lines AA and BB a plurality of identical inventive prestructured substrates 320 cut. R5 indicates a coil blank of a multiplicity of coil blanks juxtaposed in a matrix arrangement, which are different from the spatially pre-structured substrates 300 from 3 and 4 and 310 from 7 with its coil axis perpendicular to the layer direction S of the block 420 to come to rest.

The progress of the coils R5 of 9 is therefore different from the coils R1, R2, R3 and R4 by the distance of the parallel tracks 102 on the surface prestructured substrates 120 determined, and the cross section of the coil R5 is given by the thickness of the layer 120 and 320 while the progress of the coils R1, R2, R3 and R4 is given by the thickness of the substrate 100 and 110 and the cross section of the coils R1, R2, R3 and R4 is given by the thickness of the layers 300 respectively. 320 and the distance between the parallel tracks 102 respectively. 112 on the surface prestructured substrates 100 and 110 ,

10 shows a further advantageous embodiment of the present invention in a modification of 1 , Similar to the execution of 1 are a variety of similar planar prestructured substrates 100 with parallel tracks 102 to a block according to the invention 430 laminated, however, in the block 430 no substrates 200 are present with full-surface metallizations. Similar to the block 400 be out of the block 430 along the lines AA and BB, a plurality of identical spatially pre-structured substrates according to the invention 330 cut. The peculiarity of the execution of 10 is that here the metallization ends for the coil contact surfaces in the block 430 and in the spatially pre-structured substrate 330 with vertical tracks 102 not yet available. As a result, here advantageously the coil blanks R6, R7 with their longitudinal axis parallel to the layer direction S as the coil blanks R1, R2, R3 and R4 of 4 and 7 and also perpendicular to the layer direction S as the coil blank R5 of 9 to be ordered. Planar traces on the top and bottom of the substrate 330 holding the vertical tracks 102 are applied according to the desired orientation of the coil blanks R6, R7 according to the embodiments described above. Subsequently, the completed substrate 330 along the lines EE or FF are cut into a plurality of elongate strips consisting of a series of parallel continuous coil blanks R6, R7 so that two opposite side surfaces of the elongated strips consist of a plurality of juxtaposed opposing contact surfaces of the coils R6 and R7. The elongated strips are then rotated 90 ° and the two sides with the contact surfaces metallized over the entire surface (eg: by sputtering). Then the coils are separated from the strips by cuts.

It is clear that the various embodiments of the invention can be easily combined with one another by a person skilled in the art, for example: the areally prestructured substrate 110 from 5a with the block construction 430 without full-surface intermetallization of 10 or with via elements 123 from 9 ,

According to a further advantageous embodiment of the present invention, a three-dimensional block such as: the block 400 from 3 produced by pultrusion analogous to the ribbon cable production. In this case, a plurality of, for example, copper wires are pulled in parallel in a predetermined 3-D matrix arrangement and encapsulated during stranding the copper wires with insulating plastic. The further steps of producing a spatially prestructured substrate to the separation of the completed coils is analogous to the above-described embodiments.

According to the invention, in the methods and bobbins described above, the vertical conductor tracks on the one hand and the plana On the other hand, the conductor tracks and metallization ends on the top and bottom sides of the prestructured substrate each consist of different conductive materials.

Desirable is that the different materials an approximately same conductivity exhibit. By cross-sectional variation of vertical and planar Cable paths (eg: over the planar track height) let yourself the total serial resistance of both types of railway under cost and electrical Optimize aspects.

When Material for the coil turns, for example, is a conductive polymer, higher melting Thick-film conductor pastes or electrodeposited copper a whole area deposited and structured start metallization, e.g. B: platinum, into consideration.

When Material for For example, the substrate 1 is polyimide due to its dielectric constant particularly according to the invention suitable.

By the blockwise preparation according to the invention from spatially pre-structured substrates become higher vertical tracks Precision on simple inexpensive Made way. Furthermore is the disadvantageous separate production of hole connections between avoided on both sides of the substrate.

With The above-described inventive method can be coils produce benefits in batch processing, resulting in significant cost advantages and time savings are achieved. In addition, by the method according to the invention achieved a significant increase in miniaturization, as it is made possible RF coils of appropriate inductance and quality at a distance of the order of magnitude in the range of a few 100 microns between opposite Tracks and winding distances of 10 μm manufacture.

Claims (15)

Method for producing electrical components which include a volume as an inductance with a conductive layer, using spatially pre-structured substrates (US Pat. 300 ; 310 ; 320 ; 330 ) with a multiplicity of blanks (R1, R2, R3, R4, R5, R6, R7) in matrix arrangement, characterized in that the spatially pre-structured substrates ( 300 ; 310 ; 320 ; 330 ) by means of a plurality of parallel cuts (AA, BB) perpendicular to in a block ( 400 ; 410 ; 420 ; 430 ) parallel electrical conductor tracks ( 102 ; 112 ; 122 ) getting produced. Method according to claim 1, characterized in that the block ( 400 ; 410 ; 420 ; 430 ) from a multiplicity of laminated areally prestructured substrates ( 100 . 200 ; 110 . 210 . 221 ; 120 ) consists. Method according to claim 2, characterized by the steps: Step 1: Production of the plurality of areal prestructured substrates ( 100 . 200 ; 110 . 210 . 212 ; 120 ) with the multiplicity of parallel conductor tracks ( 102 ; 112 ; 122 ); Step 2: Making the block ( 400 ; 410 ; 420 ; 430 ) by laminating a plurality of areal prestructured substrates ( 100 . 200 ; 110 . 210 . 212 ; 120 ) one above the other; Step 3: Production of the multiplicity of spatially pre-structured substrates ( 300 ; 310 ; 320 ; 330 ) with a plurality of parallel vertical tracks ( 102 ; 112 ; 122 ) by cuts (AA, BB) from the block ( 400 ; 410 ; 420 ; 430 ) perpendicular to the parallel tracks ( 102 ; 112 ; 122 ); Step 4: Connection of the vertical tracks ( 102 ; 112 ; 122 ) by means of on the top and bottom of the spatially pre-structured substrates ( 300 ; 310 ; 320 ; 330 ) each arranged in parallel planar conductor tracks ( 103 . 104 ; 113 . 114 ), so that a plurality of blanks (R1, R2, R3, R4, R5, R6, R7) are formed in matrix arrangement next to each other. Step 5: Singulation of the blanks (R1, R2, R3, R4, R5, R6, R7) by cuts (CC, DD, D1-D1) at the boundaries of the blanks (R1, R2, R3, R4, R5, R6, R7). Method according to Claim 2 or 3, characterized in that the parallel conductor tracks ( 102 ; 112 ; 122 ) on a surface of the areally prestructured substrates ( 100 ; 110 ; 120 ) and in the block ( 400 ; 410 ; 420 ; 430 ) a predetermined number of areal prestructured substrates ( 100 ; 110 ; 120 ) are arranged one above the other. Method according to Claim 4, characterized in that the parallel conductor tracks ( 102 ; 112 ; 122 ) on both surfaces of the planar prestructured substrates ( 100 ; 110 ; 120 ) and in the block ( 400 ; 410 ; 420 ; 430 ) a predetermined number of areal prestructured substrates ( 100 ; 110 ; 120 ) are arranged one above the other. Method according to Claim 5, characterized in that the parallel conductor tracks ( 102 ; 112 ; 122 ) on both surfaces of the planar prestructured substrates ( 100 ; 110 ; 120 ) are formed opposite each other, and in the block ( 400 ; 410 ; 420 ; 430 ) between two areal prestructured substrates ( 100 ; 110 ; 120 ) an insulation layer ( 210 ) is arranged. Method according to Claim 5, characterized in that the parallel conductor tracks ( 102 ; 112 ; 122 ) on both surfaces of the planar prestructured substrates ( 100 ; 110 ; 120 ) are formed such that a parallel conductor track ( 102 ; 112 ; 122 ) on the one upper side of the areally prestructured substrates ( 100 ; 110 ; 120 ) between two parallel interconnects on the other upper side of the planar prestructured substrates ( 100 ; 110 ; 120 ) is arranged. Method according to one of Claims 4-7, characterized in that in the block ( 400 ; 410 ; 420 ; 430 ) a layer ( 200 ) with full-area metallization alternately with a predetermined number of areal prestructured substrates ( 100 ; 110 ; 120 ) is arranged. Process according to one of Claims 47, characterized in that in the areally prestructured substrates ( 100 ; 110 ; 120 ) with the parallel tracks ( 102 ; 112 ; 122 ) parallel through via elements ( 123 ) are formed. Method according to one of the preceding claims 2-9, characterized in that in each case two opposite parallel conductor tracks ( 102 ; 112 ; 122 ) of the spatially pre-structured substrates ( 300 ; 310 ; 320 ; 330 ) on the top or the bottom of the substrates ( 300 ; 310 ; 320 ; 330 ) with planar conductor tracks ( 103 . 104 ) get connected. Method according to claim 10, characterized in that the coil blanks (R1, R2; R3, R4; R5; R6, R7) are arranged with their longitudinal axis in the layer direction (S) or perpendicular to the layer direction (S) of the block (FIG. 400 ; 410 ; 420 ; 430 ) are arranged. Method according to claim 1, characterized in that the block ( 400 ; 410 ; 420 ; 430 ) by means of pultrusion of a plurality of suitably arranged arranged conductive wires and simultaneous plastic sheathing of the wires is produced, wherein the parallel conductor tracks ( 102 ; 112 ; 122 ) are provided by the wires. A coil produced by the method according to one of the preceding claims, characterized in that the coil has a rectangular or square cross-section, and mutually opposite parallel conductor tracks ( 102 ; 112 ; 122 ) are arranged on two opposite lateral surfaces of the coil. Coil according to claim 13, characterized in that on three lateral surfaces of the coil, the conductor tracks ( 102 ; 112 ; 122 ) are formed in a plane parallel to the coil cross section. Coil according to claim 13, characterized in that on the two other lateral surfaces of the coil the planar conductor tracks ( 113 ; 114 ) are formed at an angle to the coil cross section.