JP2004055666A - Substrate with flat coil, multilayer coil, method of manufacturing the same, and oscillating body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To centralize coils to a single board. <P>SOLUTION: In the board with a flat coil, the concave portions are provided on both surfaces of the board, the winding directions of coils embedded to both concave portions are respectively different, and both coils are electrically connected via the through-hole provided to the board. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate with a planar coil and a multilayer coil, a method for producing them, and an oscillator having the substrate with a planar coil.
[0002]
[Prior art]
In recent years, electronic devices have tended to become smaller and thinner each year. Electronic equipment having a drive system is no exception, and the miniaturization and thinning of the drive unit are indispensable conditions, and the miniaturization and thinning of magnetic components such as inductors and transformers are also required. Therefore, there is a limit to the miniaturization of a coil of a winding method in which a conventional ferrite core is wound, and a flat magnetic element combining a planar coil and a magnetic material as a chip inductor instead of the winding method is being proposed. . As the planar coil, a coil having a narrow width and a large thickness in the height direction, that is, a so-called high aspect wiring arranged at a small interval has been required.
[0003]
For example, Japanese Patent Laying-Open No. 05-198449 proposes a method of producing a planar coil by screen printing using a paste on a ceramic substrate. By this method, a thick-film coil can be printed on a substrate, and a planar coil can be manufactured. In order to increase the number of coil turns and reduce the wiring resistance, it is necessary to reduce the gap between the wirings and make the wirings thicker. Then, the aspect ratio of the coil formed of the paste formed at the time of screen printing becomes large, sag occurs before or during firing, and a short circuit occurs between adjacent wirings, thereby lowering the reliability of the coil.
[0004]
Japanese Patent Application Laid-Open No. 5-006832 proposes a method of manufacturing a flat coil having a small gap between coil conductors and having a large thickness. In this method, the gap between the coil conductors can be reduced by forming a groove in the conductor, covering with an insulating film and filling the groove with the conductor, and the coil can be made thicker by forming the groove deeper. However, in order to manufacture a coil, an etching method perpendicular to the conductor surface is selected and a wet etching method capable of etching at a high rate cannot be used because etching proceeds almost isotropically. Therefore, a reactive ion etching method, an ion beam etching method, or the like in which the etching proceeds substantially perpendicular to the conductor surface must be selected as the dry etching method. The choice of conductor material having low resistivity is limited, and copper is generally used as a coil material from the viewpoint of cost and the like.However, reactive gas in which copper is etched at a high rate in reactive ion etching is Nearly nothing. Therefore, the etching time becomes longer to form a deep groove, which causes a problem in throughput. Further, even when the groove is filled with the conductor, as the groove becomes deeper, the possibility that the conductor adheres to the side wall of the resist removed after the filling of the conductor increases. If the conductor adheres to the side wall of the resist, the conductor remains even after the removal of the resist, causing a short circuit between the adjacent conductors, thereby lowering the reliability as a coil.
[0005]
In Japanese Unexamined Patent Publication No. Hei 6-89895, the height t is divided into a plurality of pieces in order to realize a wiring having a high aspect ratio (height t / width W) as shown in FIG. Each time, the surface is covered with a flat covering layer, the portion of the covering layer above the wiring portion is removed, and the next wiring portion is laminated on the exposed wiring. However, in this method, it takes much time to form a wiring having a higher aspect ratio. In addition, since one layer of wiring is formed by lamination of divided wiring, a surface treatment step of the connection surface of the wiring is required for each lamination, and the surface treatment step is omitted particularly when copper is used as the wiring material. And the wiring resistance becomes very high. In addition, when multilayer wiring is performed using this method, the manufacturing time is further increased.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above-mentioned problems of the related art, and has as its object to integrate coils on one substrate.
[0007]
[Means for Solving the Problems]
Therefore, the present invention
A substrate with a planar coil having a planar coil on the substrate,
A first spiral planar coil disposed in a spirally provided recess on one surface of the substrate;
A second spiral planar coil disposed on a concave portion provided in a spiral shape opposite to the spiral shape on the back surface with respect to the one surface,
The substrate has a through-hole penetrating between a spiral center of the first spiral planar coil and a spiral central of the second spiral planar coil,
The first spiral coil and the second spiral coil are connected to each other through the through hole, and a substrate with a planar coil is provided.
[0008]
Also, the present invention
A method for manufacturing a substrate with a planar coil having a planar coil on the substrate,
Providing spiral concavities on the front and back surfaces of the substrate;
Providing a through hole in the substrate;
Obtaining a first spiral planar coil and a second spiral planar coil by forming a coil in each of the spiral concave portions on the front and back surfaces;
The first spiral planar coil and the second spiral planar coil are provided through the through hole penetrating between the spiral central portion of the first spiral planar coil and the spiral central portion of the second spiral planar coil. And a step of connecting to the spiral planar coil.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
The substrate with a planar coil of the present invention has coils on both surfaces of one substrate, and the coils are connected to each other, so that the coils can be integrated on one substrate. Further, the coils can be connected to each other via a through hole provided in the substrate. Further, a multilayer coil can be provided by superposing a plurality of such substrates with a planar coil.
[0010]
Although described below with examples, the substrate with a planar coil of the present invention further includes
(1) It is possible to provide a coil having a high aspect ratio and a narrow space between wirings.
Or (2) a coil having high insulation reliability between coil wirings can be provided;
Alternatively, (3) a substrate with a planar coil having a short manufacturing time can be provided.
[0011]
An oscillator such as an optical deflector using a single-layer coil or using a multilayer coil can be provided.
[0012]
This will be further described below.
[0013]
FIG. 1 is a schematic diagram illustrating a substrate with a planar coil according to the present embodiment from the surface. 101 is a substrate, 102 is a plane coil provided on the front surface side of the substrate, 103 is a plane coil provided on the back surface side of the substrate, 104 is a through hole, and 105 is a conductor layer. On both surfaces of the substrate 101, spiral planar coils 102 and 103 formed of a conductor are formed. The coil patterns of the planar coils 102 and 103 have opposite winding directions toward the same center. Each planar coil is embedded in a concave portion provided on both surfaces of the substrate 101. An insulating film (not shown) is formed between the planar coils 102 and 103 and the inner wall of the concave portion of the substrate. The coil is a fine coil whose width, the distance between the spiral inner coil and the outer coil, or the depth (thickness) embedded in the concave portion is in the range of, for example, 10 μm or more and several hundred μm.
[0014]
Further, a through hole 104 whose inner wall is covered with an insulating film is provided at the center of the spiral, and a conductor layer 105 is formed on the inner wall surface of the through hole. The inner wall surface of the conductor layer 105 itself, that is, the substrate is an insulator, a semiconductor, or a conductor that has been subjected to an insulator treatment at least where both coils are connected.
[0015]
The planar coil 102 embedded on one substrate surface (front surface side) and the planar coil 103 embedded on the other substrate surface (back surface side) are electrically connected by the conductor layer 105 formed on the inner wall surface. Connected to In the present embodiment, the conductor layer 105 is provided on all four surfaces of the inner wall of the through hole as shown in the figure. However, the conductor layer 105 does not necessarily need to be provided on all four surfaces as long as the coils 102 and 104 can be connected.
[0016]
The configuration in which the planar coil is provided on each of the front and back surfaces of the substrate is referred to as a two-layer planar coil. The two-layer planar coil having this configuration forms a concave portion in which coil wiring is buried by performing substrate member removal processing. Thereby, a recess having an aspect ratio of, for example, 10 or more can be formed. Further, even if the interval between the concave portions is small, the substrate between the concave portions is hard, and thus has sufficient mechanical strength.
[0017]
In addition, since the coil is embedded in the substrate, the coil and the substrate are fixed very strongly, and peeling of the coil due to stress can be prevented even when the aspect ratio of the coil increases. The coils formed on both sides of the substrate have the same coil width, number of turns, and coil size, and the position of the coil formed on the substrate surface and the position of the coil formed on the back surface of the substrate are the same in the front and back inward directions. Since it is arranged at the position, there is no warpage of the substrate, so that peeling due to the stress of the coil can be prevented.
[0018]
According to this embodiment, the coils are formed on both sides of the substrate, and the coil on one side and the coil on the other side are electrically connected to form a so-called two-layer planar coil, and the number of turns of the coil on one substrate is increased. be able to.
[0019]
Next, a method for producing the substrate with a planar coil will be described.
[0020]
As the substrate used in the present invention, a glass substrate, a silicon wafer, a glass epoxy substrate, or the like can be used. By using such a rigid substrate, the wall of the concave portion has high strength.
[0021]
The substrate preferably has good smoothness. By using a substrate having good smoothness, a shape to be described later can be formed by a process such as semiconductor lithography.
[0022]
As a method of forming a spiral concave portion in the substrate, the spiral concave portion is formed by semiconductor photolithography and etching. For example, a positive resist is applied to the entire surface of the substrate, exposed and developed to expose the substrate surface for providing a spiral pattern at a desired position. Alternatively, a desired spiral pattern may be exposed on the substrate surface by forming a metal film on the substrate surface and similarly removing unnecessary portions from the metal film by semiconductor photolithography and etching.
[0023]
Next, a concave portion is formed by etching the substrate member from the surface of the substrate exposed to the spiral pattern.
[0024]
The etching method may be either wet etching or dry etching. However, in order to manufacture a coil having a narrow wiring, it is desirable to perform etching perpendicular to the substrate surface in order to maintain insulation between the wirings (for example, between the inner and outer wirings of the spiral wiring). preferable. More preferably, a reactive ion etching method or an ion coupling plasma (ICP) method is preferable. The method of forming the concavity of the spiral pattern is not limited to the etching method, and the concavity may be formed by laser processing.
[0025]
If the substrate to be used is a conductor material or a semiconductor material, an insulating layer is formed in the recess of the substrate to electrically insulate between adjacent coil wires, such as between the inner and outer coils of the spiral coil. I do. As a method for forming the insulating layer, a sputtering method, a chemical deposition method, a thermal oxidation method, dipping, or the like can be used. If the substrate to be used is an insulating substrate, this insulating layer forming step can be omitted.
[0026]
As a wiring forming method for forming wiring in the concave portion, electroplating, electroless plating, embedding of a conductive paste, or the like can be used. In the case of using other electroless plating, palladium is first adsorbed on both surfaces of the substrate on which the concave portions and the through holes are formed.
[0027]
As a method of adsorption, sensidizing, which is a general method, is performed, followed by washing with water, immersing in a solution containing palladium ions as an activator, and washing again with water. For the sensitizing, for example, a hydrochloric acid solution of stannous chloride was used. This hydrochloric acid solution may use what is called a sensitizer.
[0028]
Next, a transition metal is simultaneously laminated on the concave portions on both surfaces of the substrate and the inner wall surface of the through hole by electroless plating to form a coil. As the electroless plating material, it is possible to use copper, nickel, gold, iron, silver, cobalt, palladium, tin, platinum and alloys thereof. When using electroplating, a conductive thin film such as chrome or gold thin film is deposited on the surface of the concave insulating film and the inner wall surface of the insulating film of the through hole, and the transition metal is simultaneously applied to the concave surface on both surfaces of the substrate and the inner wall surface of the through hole by electroplating. Lamination is performed by electroplating to form a coil. As the electroplating material, it is possible to use copper, nickel, gold, iron, silver, cobalt, palladium, tin, platinum and alloys thereof. In both the electroless plating and the electroplating, a conductor is formed in an unnecessary portion other than a necessary portion such as a concave portion and an inner wall surface of a through hole. In this case, it is necessary to remove the conductor formed in the unnecessary portion. In this case, for example, the entire surface of the substrate may be removed by polishing.
[0029]
In this way, the concave portion and the through hole are provided in the substrate, and the conductor can be provided in them. By providing the concave portions on the front and back surfaces of the substrate, a substrate with a planar coil (two-layer planar coil) of the present embodiment can be manufactured. The concave portions on the front surface and the rear surface may be formed in different steps. In the recesses on the front and back surfaces, a conductor can be provided in a single step by the above-described various plating methods.
[0030]
In the plating step, a wiring having a high aspect ratio (for example, an aspect ratio of 10 or more) can be manufactured. When a plurality of two-layer planar coils shown in FIG. 1 are formed on the same substrate (not shown), a plurality of two-layer planar coils can be produced simultaneously by using the above-described production method.
[0031]
Next, the multilayer coil will be described. The multilayer coil is formed by laminating a plurality of the two-layer planar coils. In other words, the configuration is such that a plurality of substrates with coils provided with coils on both surfaces are overlaid. In order to make electrical connection between the substrates with the two-layer planar coils, the end points of the wiring on the front surface of the first two-layer planar coil and the end points of the wiring on the back surface of the second two-layer planar coil are mutually true at the time of lamination. The positions of the end points of each wiring are determined so as to be arranged above. More specifically, in any of the substrates with a two-layer planar coil, the wiring end points of the respective coils on the front and back surfaces are vertically arranged on the substrate surface. Such a substrate with a two-layer planar coil is overlapped as described above, and the substrate on the back side of the other two-layer planar coil substrate facing the wiring end point of the coil on the front side of one of the two-layer planar coil substrates The wiring end points of the coils are disposed so as to face each other in the vertical direction, and can be connected to each other by a conductor.
[0032]
The material of the conductor is not particularly limited as long as it has a low resistance and can make contact with each wiring of the two-layer planar coil-mounted substrate. For example, gold can be used. In this case, gold bumps are formed at the end points of the wiring on the surface of each two-layer planar coil using a Flip-Chip bonder, and the two-layer planar coils are placed one on top of the other, heated and crimped to change the spiral direction on the front and back surfaces. A multilayer coil formed by laminating a plurality of substrates with different planar coils can be obtained.
[0033]
As a result, the manufacturing time is short, and a multilayer coil can be manufactured.
[0034]
【Example】
Hereinafter, the present invention will be described in more detail with reference to Examples.
[0035]
(First embodiment)
In this embodiment, a two-layer planar coil schematically shown in FIG. 2 was designed and manufactured. The two-layer planar coil of this example used a silicon single crystal substrate 201 having a thickness of 200 μm as a substrate. A spiral concave portion and a through hole 202 having a width of 20 μm, a depth of 80 μm, and an interval of adjacent concave portions of 20 μm were formed on both surfaces of the silicon single crystal substrate 201 by ion coupling plasma (ICP). The centers of the spiral patterns of the concave portions on the front surface and the rear surface are the same, and the winding directions are opposite. An SiN film was formed on the surface of the concave portion and the inner wall surface of the through hole by LPCVD to form an insulating film. Copper was buried in the concave portions on both surfaces of the substrate by electroplating to form planar coils 203 and 204 on each surface. The plane coils formed on each surface by the conductor layer 205 made of copper on the inner wall surface of the through hole are electrically connected. That is, the coil formed on the front surface and the coil formed on the back surface are electrically connected in series.
[0036]
Hereinafter, a manufacturing process of the two-layer planar coil of this embodiment will be described. FIG. 3 is a cross-sectional view showing a manufacturing process of the two-layer planar coil of the present embodiment. The cross-sectional view of FIG. 3 corresponds to the cross section AA ′ of FIG. Hereinafter, description will be made with reference to FIG.
[0037]
A positive resist resin (AZP4330, manufactured by Clariant) is applied to both surfaces of the silicon single crystal substrate 301 shown in FIG. 3 (3-a) using a spin coater as shown in FIG. Development is performed to form an opening pattern 302 corresponding to the through hole located at the center of the coil shape. Next, anisotropic dry etching by ICP discharge is performed on the silicon single crystal substrate to form a through-hole-shaped recess 303 as shown in FIG. In the anisotropic dry etching by the ICP discharge, SF6 and C4F8 are alternately used as an etching gas. The recesses on the front and back surfaces are not connected at this time, that is, no through holes are obtained at this time.
[0038]
Next, after removing the resist, a positive resist resin (AZP4330, manufactured by Clariant) is again applied using a spin coater, exposed and developed, and an opening pattern 304 corresponding to the spiral coil shape and the through hole shape is formed. Is formed as shown in FIG. Next, anisotropic dry etching by ICP discharge is performed on the silicon single crystal substrate 301 to form a concave portion 305 and a through hole 306 for embedding a planar coil, and the resist is removed as shown in FIG. A prepared substrate is prepared. Next, as shown by the bold line in FIG. 3F, a SiN film is formed as an insulating film 307 on the substrate surface, in the concave portions, and in the through holes by LPCVD.
[0039]
Next, palladium is adsorbed on both surfaces of the substrate on which the concave portions and the through holes are formed (not shown). As a method of adsorption, a common method is immersion in a tin chloride solution as a sensitizer, followed by washing with water, immersion in a solution containing palladium ions as an activator, and washing again with water. Next, copper is provided on the recess and the inner wall surface of the through hole by electroless plating. The planar coils 308 and 309 and the conductor layer 310 are formed. Next, if there is a laminated conductor other than the recess and the inner wall surface of the through-hole, the conductor is removed by polishing, and a substrate with a planar coil provided with planar coils on both surfaces as shown in FIG. obtain.
[0040]
As described above, the two-layer planar coil is obtained by forming a concave portion by removing a predetermined portion of the substrate member and embedding the coil wiring in the concave portion. Since the substrate member between the concave portions is hard, it has sufficient mechanical strength. Then, a spiral concave portion having a high concave aspect ratio and a narrow interval between concave portions can be obtained.
[0041]
Also, when the aspect ratio is high, the coil itself has a strong stress. If the coil is provided on the upper surface of the substrate without providing the concave portion, the coil may be separated from the substrate due to the stress. On the other hand, since the planar coil according to the present invention has a structure embedded in the substrate, the coil and the substrate are fixed (particularly, not only the bottom surface of the coil but also the side surface is fixed not only to the inner wall of the recessed portion). And peeling due to stress can be prevented even when the aspect ratio of the coil is increased. In particular, the coil obtained by the plating method is preferable because it can be very firmly fixed to the concave portion of the substrate.
[0042]
The coils formed on both sides of the substrate have the same coil width, number of turns, and coil size, and the position of the coil formed on the substrate surface and the position of the coil formed on the back surface of the substrate are the same in the front and back inward directions. Since it was arranged at the position, the warpage of the substrate was reduced. The coils are formed on both sides of the substrate, and the coil on one side and the coil on the other side are electrically connected to form a so-called two-layer planar coil, so that the number of turns of the coil on one substrate can be increased. .
[0043]
(Second embodiment)
In this embodiment, a multilayer coil schematically shown in FIG. 4 was designed and manufactured. FIG. 5 is a schematic diagram showing the electrical connection of the multilayer coil of FIG. The multilayer coil of this embodiment is configured by stacking a plurality of the two-layer planar coils 401 shown in the first embodiment. The stacked two-layer planar coils are electrically connected by gold bumps 402. More specifically, the end point 501 of the plane coil on the front surface of the two-layer planar coil and the end point 502 of the back surface are respectively referred to as the end point 504 of the planar coil 503 on the back surface of the two-layer plane coil disposed directly above at the time of lamination. And an end point 502 on the back surface is electrically connected to an end point 506 of the planar coil 505 on the surface of the two-layer planar coil disposed immediately below at the time of lamination by a gold bump 507. In order to arrange the two-layer planar coils in parallel at the time of lamination and to increase mechanical strength, gold bumps as spacers 403 are arranged.
[0044]
Hereinafter, a process of manufacturing the multilayer coil of the present embodiment will be described. FIG. 6 is a schematic view showing a manufacturing process of the multilayer coil of the present embodiment. The two-layer planar coil was manufactured in the same manner as in the first embodiment. Gold bumps 601 for electrically connecting the planar coils are formed on the ends of the planar coils formed on the surfaces of the two-layer planar coils by using a flip-chip bonder. Gold bumps having the same shape as the gold bumps formed on the ends of the planar coil are formed as spacers 602 at the four corners of the substrate by the same method. Next, alignment and heating and pressure bonding are performed so that the ends of the planar coil formed on the back surface of the two-layer planar coil to be laminated with the gold bump formed on the end of the planar coil are electrically connected.
[0045]
In the multilayer coil of the present invention, a plurality of two-layer planar coils produced at the same time are laminated on the same substrate via gold bumps to increase the number of turns of the coil wiring, so that the production time is short and the yield is high. Is very good.
[0046]
(Third embodiment)
In this embodiment, an optical deflector schematically shown in FIG. 7 was designed and manufactured. FIG. 7A is a schematic sectional view of the optical deflector, and FIG. 7B is an exploded schematic view of the optical deflector. FIG. 7A shows a BB cross section of FIG. 7B. In the optical deflector of the present embodiment, the scanning mirror 704 is angularly displaced in accordance with the magnetism generated by energizing the two-layer planar coil shown in the first embodiment and the permanent magnet 703 provided in the scanning mirror 704 portion. Then, the scanning mirror 704 reciprocates (oscillates) as shown by an arrow in the figure by means (not shown) for reversing the direction of the magnetic field. As can be seen from FIG. 7B, the scanning mirror 704 is supported on both sides by a support substrate 706 by elastic support portions 705, and can reciprocate around the elastic support portions. In this sense, the present embodiment exemplifies an oscillator including a scanning mirror 704 as a movable plate and a substrate with a planar coil. The scanning mirror 704 includes a reflecting mirror portion 702 on one surface side and a plate-shaped scanning mirror 704 on which a thin-film permanent magnet 703 magnetized on the other surface side is formed. Specifically, it illustrates an optical deflector that can change incident light by reflecting the light with an oscillating reflecting mirror. This optical deflector may be used as an optical deflector driven by resonance. Alternatively, it may be used as a resonance type galvanometer mirror. The frequency for resonance driving is, for example, a frequency (band) of 14 KHz to 25 KHz.
[0047]
This optical deflector can reduce power consumption and apply a large magnetic field to the permanent magnet formed on one side of the scanning mirror because the coil wiring is configured with a high aspect ratio and a narrow space between wirings. The scanning mirror could be displaced angularly. Further, since the coils are formed on both sides of the substrate, the number of turns on one substrate can be increased, and the size of the optical deflector can be reduced.
[0048]
(Fourth embodiment)
In this embodiment, an optical device using the optical deflector shown in the third embodiment will be described. FIG. 8 is a diagram illustrating an example of an image display device as an optical device. 8, reference numeral 801 denotes an optical deflector group 801 in which two optical deflectors shown in FIG. 7 are arranged so that their deflection directions are orthogonal to each other. In this case, an optical scanner device that raster-scans incident light in horizontal and vertical directions Used as 802 is a laser light source. Reference numeral 803 denotes a lens or a lens group, 804 denotes a writing lens or a lens group, and 805 denotes a projection surface. The laser light incident from the laser light source 802 undergoes predetermined intensity modulation related to the timing of optical scanning, and is two-dimensionally scanned by the optical deflector group 801. The scanned laser beam forms an image on the projection surface 805 by the writing lens 804. Note that, of the two optical deflectors, only one optical deflector in the third embodiment may be used. In that case, it is preferable to use it as a deflector for moving light in the horizontal scanning direction on the projection surface.
[0049]
FIG. 9 is a diagram showing an example in which the optical deflector of the present invention is used in an electrophotographic image forming apparatus. In FIG. 9, reference numeral 901 denotes the optical deflector shown in FIG. 7, which is used as an optical scanner for scanning incident light one-dimensionally. 902 is a laser light source. Reference numeral 903 denotes a lens or a lens group, 904 denotes a writing lens or a lens group, and 906 denotes a photoconductor. The laser light emitted from the laser light source undergoes predetermined intensity modulation related to the timing of optical scanning, and is one-dimensionally scanned by the optical deflector 901. The scanned laser beam forms an image on the photoconductor 906 by the writing lens 904. The photoconductor 906 is uniformly charged by a charger (not shown), and the light is scanned thereon to form an electrostatic latent image. It is formed. Next, a toner image is formed on the image portion of the electrostatic latent image by a developing device (not shown), and this is transferred and fixed to, for example, a paper (not shown), thereby forming a visible image on the paper.
[0050]
【The invention's effect】
As described above, the substrate with a planar coil of the present invention can have a coil with a large number of turns on one substrate by providing the coil on the front and back surfaces and connecting them to each other.
[0051]
Alternatively, the two-layer planar coil can be formed even if the recess has a high aspect ratio and the gap between the recesses is narrow because the recess is formed by removing the substrate and embedding the coil wiring. Since the coil is embedded in the substrate, the coil and the substrate are very firmly fixed to each other, and even if the aspect ratio of the coil is increased, peeling due to stress can be prevented. In addition, since coils of the same pattern are arranged on both surfaces of the substrate, there is no warpage of the substrate, so that peeling due to coil stress can be prevented. Coil is formed on both sides of the board, and the coil on one side and the coil on the other side are electrically connected to form a so-called two-layer planar coil, so the number of coil turns can be increased with respect to the board area It is. Since the relationship between the width l and the depth h of the coil wiring is l <h, the electric resistance of the coil can be reduced, and a strong magnetic field can be generated with low power consumption when a current flows through the coil. be able to. Further, since the two-layer planar coil can be formed by laminating the conductor once, the manufacturing time can be reduced.
[0052]
Since a plurality of two-layer planar coils produced at the same time are laminated on the same substrate via gold bumps to increase the number of turns of the coil wiring, the production time is short and the yield is very good.
[Brief description of the drawings]
FIG. 1 is a diagram showing one embodiment of a two-layer planar coil.
FIG. 2 is a diagram showing another embodiment of a two-layer planar coil.
FIG. 3 is a diagram showing one embodiment of a method for manufacturing a two-layer planar coil.
FIG. 4 is a perspective view showing one embodiment of a multilayer coil.
FIG. 5 is a perspective view illustrating electrical connection of a multilayer coil.
FIG. 6 is a diagram illustrating an embodiment of a method for manufacturing a multilayer coil.
FIG. 7A is a diagram showing an embodiment of an optical deflector using a two-layer planar coil. FIG. 7B is an exploded view of the optical deflector of FIG.
FIG. 8 is a diagram showing an embodiment of an optical device using an optical deflector.
FIG. 9 is a diagram showing another embodiment of an optical device using an optical deflector.
FIG. 10 is a diagram showing an example.
[Explanation of symbols]
101 substrate
102 Flat coil (substrate surface)
103 flat coil (back side of substrate)
104 Through hole
105 conductor layer 201 silicon single crystal substrate
202 through hole
203 Planar coil (substrate surface)
204 plane coil (back side of substrate)
205 Conductive layer
301 silicon single crystal substrate
302 Through-hole opening pattern
303 recess with through-hole shape
304 spiral coil pattern
305 recess for embedding flat coil
306 Through hole
307 insulating film
308 Flat coil (substrate surface)
309 Flat coil (back side of substrate)
310 conductor layer
401 two-layer planar coil
402 Gold Bump
403 spacer
501 End point of the planar coil on the surface
502 End point of flat coil on the back
503 Flat coil on the back
504 End point of flat coil on the back
505 Surface coil
506 End point of planar coil on surface
507 Gold bump
601 Gold bump
602 spacer
701 2-layer planar coil
702 Reflecting mirror
703 permanent magnet
704 scanning mirror
801 Optical deflector
802 laser light source
803 lens group
804 writing lens group
805 Projection plane
901 Optical deflector
902 Laser light source
903 lens group
904 writing lens group
906 photoconductor

Claims (10)

A substrate with a planar coil having a planar coil on the substrate,
A first spiral planar coil disposed in a spirally provided recess on one surface of the substrate;
A second spiral planar coil disposed on a concave portion provided in a spiral shape opposite to the spiral shape on the back surface with respect to the one surface,
The substrate has a through-hole penetrating between a spiral center of the first spiral planar coil and a spiral central of the second spiral planar coil,
The substrate with a planar coil, wherein the first spiral coil and the second spiral coil are connected via the through hole. The substrate with a planar coil according to claim 1, wherein the substrate is an insulating substrate. The substrate with a planar coil according to claim 1, wherein the substrate is a silicon single crystal substrate. 2. A plurality of the substrates with planar coils according to claim 1, wherein the substrates with planar coils are arranged so as to face each other, and the spiral coils of the opposing substrates are connected to each other at a spiral outer end. A multilayer coil characterized by: 2. A multi-layer coil comprising: a plurality of the planar coil-attached substrates according to claim 1 facing each other; and a step of connecting the spiral coils of the opposed substrates to each other at a spiral outer end. Production method. 2. A substrate having the planar coil according to claim 1, and a movable plate having a permanent magnet, both sides of which are supported by a shaft and provided to face the substrate with the planar coil, and which is movable about the axis. Oscillator characterized by the following. The oscillating body according to claim 6, wherein the movable plate has a mirror. A method for manufacturing a substrate with a planar coil having a planar coil on the substrate,
Providing spiral concavities on the front and back surfaces of the substrate;
Providing a through hole in the substrate;
Obtaining a first spiral planar coil and a second spiral planar coil by forming a coil in each of the spiral concave portions on the front and back surfaces;
The first spiral planar coil and the second spiral planar coil are passed through the through-hole penetrating between the spiral central portion of the first spiral planar coil and the spiral central portion of the second spiral planar coil. And a step of connecting the spiral flat coil to the substrate. The method for manufacturing a substrate with a planar coil according to claim 8, wherein the substrate is an insulating substrate, and further comprising a step of providing a conductor on the wall of the recess and the through hole. 9. The method according to claim 8, wherein the substrate is a silicon single crystal substrate, comprising a step of providing an insulating film on the concave portion and the wall surface of the through hole, and a step of forming a conductive film on the insulating film. 10. Of manufacturing a substrate with a planar coil.

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