JP2006310758A - Circuit wiring board and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit wiring board which is densified by forming conductors without clearance on the circuit wiring board and to provide its manufacturing method. <P>SOLUTION: The circuit wiring board has several first conductors 103 which are formed with clearances 108 one another on a conductor forming surface 102a of an insulating substrate 102, and first insulators 104 which are formed respectively on first exposed surfaces 103a of the first conductors 103. In this case, second conductors 105 are formed in the clearances 108 and second insulators 106 are formed on second exposed surfaces 105a of the second conductors 105 with fusing with the first insulators 104. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rigid or flexible circuit wiring board and a method for manufacturing the same, and more specifically, a high-density circuit wiring board in which a second conductor is formed in a gap portion sandwiched between adjacent first conductors, and It relates to the manufacturing method.

  In conventional printed circuit wiring boards, regardless of the material of the insulating base such as rigid or flexible, the area between adjacent conductor circuits remains a space so as to be displayed as a line and space (Patent Document) 1). For this reason, the main technique for increasing the density of the circuit wiring board is how to narrow the conductor circuit width and the interval between the conductor circuits.

  In Patent Document 2, a first wiring layer is provided on an insulating substrate, a first wiring protection layer is formed on the outer surface of the first wiring layer, and then the upper end of the first wiring protection layer is formed. After forming the conductor layer over the entire surface to be thicker, and then polishing the entire surface from the upper surface of the conductor layer to the first protective layer, the second wiring protective layer is formed, and then unnecessary portions are removed. An example of forming the second wiring layer is described.

JP 2001-284749 A Japanese Patent Laid-Open No. 2005-5422

  However, since the conventional printed circuit wiring board of Patent Document 1 requires a space between the conductors, there is a limit to increasing the density, and the conductor width and the width of the space are reduced. As a result, there is a problem that the yield is lowered while realizing higher density. Furthermore, regarding the relationship between the conductor thickness and the conductor spacing, the conductor spacing has to be secured approximately twice the conductor thickness due to processes such as etching, and there has been a limit to increasing the density.

  On the other hand, there is a method of forming a conductor circuit by an additive method, but when a conductor is formed by a plating method or the like, a resist layer having a thickness corresponding to that must be formed in order to ensure the plating conductor thickness. However, a considerable resist width is required to maintain such a resist shape. As a result, there was a limit to increasing the density of circuit wiring boards.

  In Patent Document 2, a conductor layer is formed on the front surface so as to be thicker than the upper end of the first wiring protective layer, and then the entire surface from the upper surface of the conductor layer to the first protective layer is polished, The wiring protective layer is then formed, and then the unnecessary portion is removed to form the second wiring layer. Therefore, the polishing of the conductive layer not only increases the elongation of the base material and conductive layer, but also a thin flexible substrate. In the case of wood, there is a problem that it is torn.

  Further, the second conductor layer is formed on the entire surface so as to be thicker than the upper end of the first wiring protective layer, and polishing can be performed only up to the first wiring protective layer. Could not be the same thickness as the first conductor layer, and could not be made even thinner.

  The present invention has been made in order to solve the above-described problems, and provides a circuit wiring board having a high density by forming a conductor on the circuit wiring board without gaps, and a method for manufacturing the circuit wiring board. For the purpose.

  In order to achieve the above object, the present invention is configured as follows.

That is, in the method for manufacturing a circuit wiring board according to the first aspect of the present invention, the first wirings covering the first exposed surface of the first conductor with the first insulating material are arranged on the conductor forming surface of the insulating base material. For circuit wiring boards with multiple gaps,
Forming a second conductor in the gap,
Forming a second insulating material on the second exposed surface of the second conductor while fusing the first insulating material;
It is characterized by that.

  In the first aspect, the first conductor is formed on the conductor formation surface before the second conductor is formed, and after the first conductor is formed, the first exposed surface is formed on the first exposed surface by an electrodeposition coating method. One insulating material may be formed, and after the first insulating material is formed, the first insulating material may be heated and softened to be in close contact with the conductor forming surface.

  Furthermore, the second insulating material may be formed on the second exposed surface by an electrodeposition coating method, and may be fused with the first insulating material by heating after the formation.

  Further, the second insulating material may be formed so as to cover the first insulating material and the second exposed surface, and the second conductor has a thickness and a material different from those of the first conductor. May be formed.

  The circuit wiring board according to the second aspect of the present invention is manufactured by the method for manufacturing a circuit wiring board according to the first aspect.

  According to the manufacturing method of the circuit wiring board of the first aspect of the present invention and the circuit wiring board of the second aspect described above, the second conductor is placed in the gap between the first conductors covered with the first insulating material. Since it is formed, a high-density circuit wiring board can be realized, which can greatly contribute to downsizing and space saving of the wiring board and components.

  Japanese Patent Laid-Open No. 63-301591 discloses that a cover lay as an insulating film is formed on the surface of a conductor. However, after the cover lay is formed, a space between adjacent conductors is formed. Furthermore, the technical idea of forming a conductor is neither disclosed nor suggested. That is, a coverlay is a film coated to insulate and protect the conductor part of a flexible printed wiring board, except that it is removed in the conductor part necessary for connection with other parts such as a land part and a terminal part. (JIS Industrial Glossary Dictionary (5th edition)). Therefore, the above-mentioned cover lay protects the conductor part in order to prevent the conductor part from being deteriorated by other objects coming into direct contact with the conductor part, and is provided at the final stage of circuit formation. is there. Therefore, Patent Document 1 does not disclose or suggest that a conductor is further formed in a space portion between adjacent conductors after the cover lay is formed.

  In the present invention, after the first insulating material is formed on the first conductor, the second conductor is formed as a thin film by any one of electroless plating, sputtering, and vacuum deposition, and the second conductor of the thin film is formed. Portions other than those necessary for formation can be removed by photoetching or polishing. Thereafter, a portion necessary for forming the second conductor can be formed to a necessary thickness by electroplating. Therefore, the thickness of the second conductor can be formed even if it is less than the thickness of the first conductor.

  A circuit wiring board according to an embodiment of the present invention and a method for manufacturing the circuit wiring board will be described below with reference to the drawings. In each figure, the same reference numerals are given to the same components.

  A circuit wiring board 101 according to this embodiment shown in FIG. 1 includes a first conductor 103 formed on a conductor forming surface 102a of a rigid or flexible insulating base material 102, and a first exposed surface of the first conductor 103. 1 insulating material 104, a second conductor 105 formed in a space between adjacent first conductors 103, which is a conductor different from the first conductor 103, and a second exposed surface of the second conductor 105 And a second insulating material 106 to be covered.

  In the circuit wiring board 101 configured as described above, since the second conductor 105 is also formed in the space portion sandwiched between the adjacent first conductors 103, the circuit wiring has a higher density than the conventional circuit wiring. A board is realized, which can greatly contribute to miniaturization and space saving of wiring boards and components.

  In the present specification, the high-density circuit wiring board indicates a conductor width and a gap between conductors, that is, a so-called line and space of about 10 to about 300 μm.

  Below, the manufacturing method of the circuit wiring board 101 is demonstrated with reference to FIG.2 and FIG.3.

  As shown in FIG. 2A, in the rigid or flexible insulating substrate 102, for example, a copper foil 107 as a conductive material is bonded to the entire surface of the conductor forming surface 102a, and the copper foil 107 is dried. By laminating the film and removing unnecessary portions by a photoetching method, the first conductor 103 is formed on the insulating substrate 102 as shown in FIG. 2B and step S1 of FIG.

  Next, a resin material for electrodeposition coating is applied to the first conductor 103 by an electrodeposition coating method, as shown in FIG. 2, (c) and step S2 in FIG. An epoxy resin, a polyimide resin, an acrylic resin, a fluorine resin, or the like is deposited on the entire exposed surface 103a to form the first insulating material 104. In addition, the 1st wiring 114 is formed with the 1st conductor 103 and the 1st insulating material 104 which coat | covered the exposed surface 103a of the said 1st conductor. In FIG. 2C, reference numeral 108 denotes a gap formed between the adjacent first conductors 103 coated with the first insulating material 104, that is, a gap between the adjacent first wirings 114. pointing.

  The following effects can be obtained by using the electrodeposition coating method for forming the first insulating material 104 on the exposed surface 103a of the first conductor 103. That is, when an insulating film is formed on the exposed surface of a conductor using, for example, a photoresist or a printing resist, the distance between the conductor and the position of the insulating film due to expansion / contraction or mechanical accuracy in the insulating base material, the exposure mask, and the printing plate. Therefore, it is difficult to form an insulating film with the minimum necessary width. On the other hand, in the electrodeposition coating method, since the insulating film is deposited only on the conductor through which electricity passes, the positional deviation between the conductor and the insulator does not occur. Therefore, it is possible to reliably form the insulating film with the necessary minimum width. Therefore, the thickness of the second conductor 105 formed on the insulating substrate can be stably secured.

  The first insulating material 104 can be substantially uniform in thickness over the entire surface of the first exposed surface 103a by drying and softening by heating after the electrodeposition in step S3 of FIG. Moreover, the thickness can be controlled. The thickness control operation is called leveling. Moreover, the thickness of the 1st insulating material 104 changes with the components of the resin material for electrodeposition coating. When the components of the electrodeposition coating resin material are the same, the film thickness 1032 of the electrodeposition coating resin material present in the flat portion 1031 of the first conductor 103 shown in FIG. It can be controlled by the heating temperature and heating time of the material. The thickness of the first insulating material 104 becomes thinner as the film thickness 1032 is smaller, the heating temperature is higher, and the heating time is longer. If the thickness of the first insulating material 104 is too thin, the electrical insulation at the corner portion 1033 of the first conductor 103 deteriorates, which is not preferable. Therefore, from the viewpoint of electrical insulation of the first conductor 103, the thickness of the first insulating material 104 is 3 to 50 μm, preferably 5 to 30 μm. In order to obtain such a thickness, for example, the heating temperature is preferably about 150 to 270 ° C., and the heating time is preferably about 10 to 20 minutes. In addition, at the rising portion 1034 of the first conductor 103 that extends substantially perpendicular to the insulating base material 102, the electrodeposition coating resin material droops due to the above-described softening of the electrodeposition coating resin material by heating. . Due to the sagging, the resin material for electrodeposition coating, that is, the first insulating material 104 flows on the conductor forming surface 102a of the insulating base material 102 to form a bottom portion 1036. By forming the bottom portion 1036, the adhesion between the resin material for electrodeposition coating, that is, the first insulating material 104 and the insulating base material 102 can be improved. In addition, at this time, a terminal portion or the like that does not need to be covered with the first insulating material 104 may be masked in advance with a photoresist, ink, tape, or the like so that the first insulating material 104 is not deposited by electrodeposition. . The masking can be peeled off after the first insulating material 104 is formed or before the surface treatment is performed on the terminal portion or the like, or can be removed with a laser. In addition, due to the sagging of the electrodeposition coating resin material, the thickness 1035 of the electrodeposition coating resin material in the rising portion 1034 is equal to the film thickness 1032 of the electrodeposition coating resin material present in the flat portion 1031 of the first conductor 103. 1/2 to 3 times, preferably about 1 to 2 times.

  Next, after forming a thin film by performing electroless copper plating on the conductor forming surface 102a of the insulating base material 102 in which the first conductor 103 is coated with the first insulating material 104, an unnecessary portion of the formed thin film is formed. As shown in FIG. 2 (d), the copper plating of the portion (other than the portion necessary for forming the second conductor 105 of the thin film formed by electroless copper plating) is removed by photoetching or polishing. The copper plated portion 109 is formed only on the conductor forming surface 102a in the gap 108. The electroless plating can be selectively formed at a place other than the first insulating material 104 depending on conditions. However, when the electroless plating is formed on the whole including the insulating base material 102 and the first insulating material 104. The electroless-plated portion that is unnecessary for the formation of the second conductor 105 described below is removed by a physical method such as photoetching or polishing, and then the conductor layer is thickened to the required thickness by electroplating. . Further, a sputtered film or a vapor deposited film can be used instead of the electroless plating. At this time, the second conductor 105 can be formed with a thickness equal to or less than that of the first conductor 103.

  When the thickness of the second conductor 105 is equal to or less than the thickness of the first conductor 103, it is preferable that the thickness of the second conductor 105 is about 3 to 10 μm thinner than the thickness of the first conductor 103. This is due to the following reason. That is, as will be described later, when the second insulating material 106 is formed using an ink or a resin such as a solder resist, the resin does not melt as in the electrodeposition coating method, and therefore the ink or the resin such as a solder resist is applied. In some cases, bubbles may be generated, resulting in poor insulation. Therefore, as shown in FIG. 17, if the thickness of the second conductor 105 is made 3 to 10 μm thinner than the thickness of the first conductor 103 and the thickness of the second insulating material 106 is made thicker by that amount ( In other words, when the second insulating material 106 is formed so that the surface of the second insulating material 106 covering the second conductor 105 and the surface of the first insulating material 104 covering the first conductor 103 are substantially flush with each other), The insulation failure can be prevented. In relation to the thickness, the thickness of the second conductor 105 is preferably 3 μm or more so that conductor cracks due to expansion and contraction and bending do not occur.

  The copper plating portion 109 is necessary when the second conductor 105 is formed by plating. For example, when the second conductor 105 is formed by a printing method or a dispenser using a metal-containing ink or paste. No need to form.

  Next, electrolytic copper plating is performed on the copper plating portion 109 in the gap 108, and as shown in FIG. 2 (e) and step S4 in FIG. 3, the first conductor 103 coated with the first insulating material 104 is applied. The second conductor 105 is formed between each other, that is, between the first wirings 114. As described above, in this embodiment, since the copper plating portion 109 is formed on the entire surface of the adjacent first conductor 103 between the first insulating materials 104, the second conductor 105 in the present embodiment is The both sides are formed in contact with the first insulating material 104. However, the formation of the second conductor 105 is not limited to this form, and the copper plating portion 109 and the second conductor 105 are formed so that both sides of the second conductor 105 do not contact the first insulating material 104. May be. Further, the thickness II of the second conductor 105 from the conductor forming surface 102a is the same as the thickness of the first conductor 103, but may be a different thickness. The resistance values of the first conductor 103 and the second conductor 105 can be made different by changing the thickness of the conductor. The second conductor 105 can also be formed by embedding a metal-containing ink or paste in the gap 108 by a printing method or a dispenser. The material of the second conductor 105 may be the same as the material of the first conductor 103, but may be different. For example, the first conductor 103 is made of copper, and the second conductor 105 is made of nickel. Thus, the resistance value can be changed as necessary by changing the materials of the first conductor 103 and the second conductor 105.

  Next, as shown in FIG. 2, (f) and step S5 of FIG. 3, the exposed surface 105a of the formed second conductor 105 is coated with an epoxy resin, a polyimide resin, an acrylic resin, a fluorine resin by an electrodeposition coating method. And the like, and then heated to form a uniform second insulating material 106. In the present embodiment, the second insulating material 106 is formed so as to have the same height as the first insulating material 104 from the conductor forming surface 102a. In addition, after the second insulating material 106 is formed, the second insulating material 106 is heated, so that the second insulating material 106 is fused to the first insulating material 104 that covers the adjacent first conductor 103. Thereby, the insulation of the 2nd conductor 105 can be improved. The heating temperature for the second insulating material 106 is about 150 to 270 ° C., and the heating time is preferably about 10 to 20 minutes. The heating temperature and time for the second insulating material 106 may be equal to the heating temperature and time for the first insulating material 104.

  In addition, the formation of the second insulating material 106 is not limited to the electrodeposition coating method, but can also be formed with ink, resin, coverlay film, or the like using a solder resist or the like. In short, the second conductor 105 can be selectively covered. If it is. On the other hand, as shown in FIG. 5, not only the second conductor 105 but also the first insulating material 104 of the first conductor 103 is entirely covered, using a solder resist or the like with ink, resin, coverlay film, etc. The second insulating material 106 can also be formed.

  With the above operation, as shown in FIG. 6, a high-density circuit wiring board 101 in which the second conductor 105 is formed between the adjacent first wirings 114 is manufactured on the insulating base 102. In addition, terminal portions 111 are formed at end portions of the first conductor 103 and the second conductor 105. The terminal portion 111 masks a part of the first conductor 103 and the second conductor 105 when the first insulating material 104 and the second insulating material 106 are formed in the above-described steps S2 and S5. As shown in FIG. 7, the first conductor 103 and the second conductor 105 are exposed without forming the first insulating material 104 and the second insulating material 106. As shown in FIG. 8, at the end portions of the first conductor 103 and the second conductor 105, a gap 112 is provided between the first conductor 103 and the second conductor 105, and the first conductor 103 and the second conductor 105. It is also possible to take a shape with a wider interval. Further, the first conductor 103 and the second conductor 105 including the first insulating material 104 and the second insulating material 106 are not limited to those extending linearly, but have a bent shape as shown in FIG. May be.

  The high-density circuit wiring board 101 manufactured in this way also has power supply leads 115 formed on the insulating base material 102 from the respective terminals 111 as shown in FIG. The first conductor 103, the first insulating material 104, the second conductor 105, and the end portion 116 of the second insulating material 106 are cut and separated at the time of outer shape processing or the like.

  Further, as shown in FIG. 10, the through hole 113 may be formed in a necessary portion, for example, in the vicinity of the terminal portion 111. In the case where the through hole 113 is formed, as a matter of course, a conductor portion that is electrically connected by the through hole 113 is formed in a portion corresponding to the through hole 113 on both the front and back surfaces of the insulating base material 102. When forming the through hole 113 in the first conductor 103, before forming the first conductor 103, a hole for the through hole 113 is formed through the insulating base material 102, and the hole is further formed by through hole plating. Conductors are formed inside, and the front and back conductors are connected. Thereafter, as described above, the first conductor 103 and then the first insulating material 104 are formed, and the first conductor 103 and the first insulating material 104 are also formed on the inner surface of the hole. Further, when forming the through hole 113 in the second conductor 105, after forming the first insulating material 104 and before forming the second conductor 105, it penetrates the insulating base material 102 and is used for the through hole 113. A hole is formed. Thereafter, as described above, the second conductor 105 and then the second insulating material 106 are formed, and the second conductor 105 and the second insulating material 106 are also formed on the inner surface of the hole. The through hole 113 can also be formed in the conductor exposed portion of the terminal portion 111. In this case, of course, no insulating material is formed in the through hole 113.

  By forming the circuit wiring board 101 as described above, the gap between the first conductors 103 covered with the first insulating material 104, that is, the gap 108 formed between the first wirings 114 is changed. Since the two conductors 105 are formed, a high-density circuit wiring board can be realized, which can greatly contribute to downsizing and space saving of the wiring board and components.

  The first conductor having a width of about 80 μm and a length of 100 mm is obtained by laminating a dry film on a flexible substrate material in which 9 μm of copper is bonded to a 25 μm-thick polyimide base film corresponding to the insulating base material 102, and by photoetching. 100 lines 103 having a line and space of 200 μm are formed. Such a group of first conductors 103 is referred to as a first conductor circuit.

  Next, a masking tape for plating is applied to both end portions 3 mm in the length direction of each first conductor 103 to mask the terminal portion 111, and then a modified epoxy resin for electrodeposition coating is applied at a voltage of 200 V for 30 seconds. Then, the first insulating material 104 is formed on the exposed surface 103a of the first conductor 103 by an electrodeposition coating method. Thereafter, the first insulating material 104 was dried at 190 ° C. for 10 minutes, softened, melted and leveled, and the film thickness 1032 of the flat portion 1031 was 20 μm, and the thickness 1035 of the rising portion 1034 was 30 μm.

  Thereafter, the masking tape of the terminal part 111 is peeled off and electroless copper plating is applied to the whole. Next, the electroless copper plating formed on the portion where the first insulating material 104 is formed and the portion other than the portion where the second conductor 105 is formed is etched and removed by a photoetching method. Next, 9 μm of electrolytic copper plating was formed on the remaining portion where the second conductor 105 was to be formed, and 99 second conductors 105 were formed. The second conductor 105 group is referred to as a second conductor circuit.

  Next, a masking tape for plating is applied to both terminal portions 3 mm in the length direction of each second conductor, and then a modified epoxy resin for electrodeposition coating is applied to the exposed surface 105 a of the second conductor 105 at a voltage of 200 V for 30 seconds. Then, the second insulating material 106 was formed by electrodeposition, dried at 190 ° C. for 10 minutes, softened, melted and leveled to form the second insulating material 106 having a thickness of 20 μm. At the same time, integration with the first insulating material 104 was attempted.

  Thereafter, the masking tape was peeled off, nickel gold plating was applied to the terminal portion 111, and the outer shape was pressed to obtain a high-density flexible circuit wiring board 101 having a width of 20.5 mm, a length of 100 mm, and 199 circuits.

  In the flexible substrate material in which 9 μm copper is bonded to both sides of a 25 μm thick polyimide base film corresponding to the insulating base material 102, the through hole 113 is provided in a necessary portion where the first conductor 103 is to be formed. Drill a hole. Then, copper plating is formed at 12 μm by electroless copper plating and electrolytic copper plating including the holes. Next, the dry film is laminated, and 100 first conductors 103 having a width of about 80 μm and a length of 100 mm are formed on one side of the flexible substrate material by a photoetching method with a line and space of 200 μm. Note that both end portions of the first conductor 103 were extended by 50 mm and formed in a fan shape with a width of about 80 μm as a line and space of 400 μm. Simultaneously with the formation of the first conductor 103, 100 first conductors 103 having a width of about 80 μm and a length of 8 mm were formed on the other surface of the flexible substrate material. Note that both ends of the first conductor 103 formed on the front and back surfaces of the flexible substrate material are formed in the same shape and the same size so as to correspond to each other.

  Thereafter, a dry film is laminated on both sides of the flexible substrate material, and the masking dry film is developed and left on both ends 3 mm of the first conductor 103 on both sides of the flexible substrate material by photolithography. The terminal portions 111 on both sides of the mask are masked. Thereafter, a modified epoxy resin for electrodeposition coating is applied at a voltage of 200 V for 30 seconds, and the epoxy resin is electrodeposited on the exposed surfaces 103a of the first conductor 103 on both surfaces of the flexible substrate material, thereby forming the first insulating material 104. . Thereafter, the first insulating material 104 is dried at 190 ° C. for 10 minutes, softened, dissolved, and leveled, and the film thickness 1032 of the flat portion 1031 of the first conductor 103 on both sides of the flexible substrate material is 20 μm, and the rising portion 1034 A first insulating material 104 having a thickness of 30 μm was formed. Thereafter, the masking dry film of the terminal portion 111 was peeled off with a chemical.

  Next, at the location where the second conductor 105 is to be formed, a hole is formed on the flexible substrate material where a through hole is required, and electroless copper plating is performed on both sides of the flexible substrate material including the hole, The electroless copper plating on the surface other than the portion to be the second conductor 105 is etched away by etching. Subsequently, 9 μm of electrolytic copper plating was applied to the remaining electroless copper plating portion to form 99 second conductors 105. Thereafter, a coverlay film having a thickness of 12.5 μm was thermocompression-bonded as an insulating layer to a necessary portion other than the terminal portion 111 including the surfaces of the second conductor 105 and the first conductor 103. Thereafter, nickel gold plating was applied to the terminal portion 111, and the outer shape was pressed to obtain a high-density flexible circuit wiring board 101 having a maximum width of 43 mm, a length of 200 mm, and a circuit number of 199 with widened circuits at both ends.

  Furthermore, the circuit wiring board 101 described with reference to FIGS. 1 to 10 and the manufacturing method thereof can be applied to adopt the following configuration.

  That is, as described above, the first conductor 103 and the second conductor 105 including the first insulating material 104 and the second insulating material 106 may be bent as shown in FIG. As shown in FIG. 11, the first conductor 103 and the second conductor 105 may be arranged in a spiral shape, and the coil 120 may be configured by the first conductor 103 and the second conductor 105. The shape of the coil 120 is not limited to the circular shape as shown in FIG. 11, but may be a square as shown in FIG. Such a coil 120 can be used for, for example, an inductor, a small motor, a solenoid, an antenna, and the like.

  Furthermore, as shown in FIG. 13, the coil member 121 which formed the coil 120-1 and the coil 120-2 with the 1st conductor 103 and the 2nd conductor 105 can also be formed in the front and back both surfaces of the insulation base material 102. FIG. . In FIG. 13, in the thickness direction 102 b of the insulating base material 102, the coil 120-1 and the coil 120-2 make the first conductor 103 and the first conductor 103 face each other, and the second conductor 105 and the second conductor 105 are made to face each other. Although they are arranged to face each other, that is, they are arranged to face the same type of conductor, but not limited to this, the first conductor 103 and the second conductor 105 are placed, that is, different kinds of conductors are faced to each other. May be.

  Furthermore, as shown in FIG. 14, a coil assembly 123 formed by bonding a plurality of the coil members 121 with an adhesive 122 can be formed. Also in the coil assembly 123, not only a configuration in which the same kind of conductors are opposed to each other between the coil members 121 but also a configuration in which different kinds of conductors are opposed may be adopted. Such a coil assembly 123 can be used for, for example, an inductor, a small motor, a solenoid, an antenna, and the like.

  Furthermore, as a modification of the coil assembly 123, a form such as a coil assembly 123-1 shown in FIG. The coil assembly 123-1 has a configuration in which the coil 120 is stacked with the adhesive 122 on the coil 120-1 in one coil member 121. The number of coils 120 to be stacked is not limited to one and may be plural. The conductors facing each other between the coils 120 may be the same type or different types.

  When the coil 120 is stacked on the coil 120-1, an insulating material 124 is formed on the coil 120-1 as in the coil assembly 123-2 shown in FIG. You may form the 1st conductor 103 and the 2nd conductor 105 in the process mentioned above. Of course, the number of layers of the coil 120 may be one or plural.

  By producing the coil by the above-described method, the second conductor is formed in the gap between the first conductors covered with the first insulating material, so that a high-density coil can be realized. This can greatly contribute to miniaturization, space saving, and improvement of coil performance.

  Examples of the coil 120 described above will be described below.

  A dry film is laminated on a flexible substrate material of 9 μm copper bonded to a 25 μm thick polyimide base film corresponding to the insulating base material 102, and the first is about 100 μm wide by a photoetching method with a conductor spacing of 150 μm. The conductor 103 is spirally formed for five turns. Thereafter, a masking tape for plating is applied to 3 mm in the length direction at the beginning and end of winding of the coil, and after masking the terminal portion 111, a modified epoxy resin for electrodeposition paint is applied at a voltage of 200 V for 30 seconds, The first insulating material 104 is formed on the exposed surface 103a of the first conductor 103 by an electrodeposition coating method. Thereafter, the first insulating material 104 was dried at 190 ° C. for 10 minutes, softened, melted and leveled, and the film thickness 1032 of the flat portion 1031 was set to 30 μm, and the thickness 1035 of the rising portion 1034 was set to 25 μm.

  Thereafter, the masking tape of the terminal part 111 is peeled off and electroless copper plating is applied to the whole. Next, the electroless copper plating formed on the portion where the first insulating material 104 is formed and the portion other than the portion where the second conductor 105 is formed is etched and removed by a photoetching method. Next, 18 μm of electrolytic copper plating is formed on the remaining portion where the second conductor 105 is to be formed, and the second conductor 105 is spirally formed for 4.5 revolutions with a width of 100 μm.

  Next, a masking tape for plating is applied to both terminal portions 3 mm in the length direction of each second conductor, and then a modified epoxy resin for electrodeposition coating is applied to the exposed surface 105 a of the second conductor 105 at a voltage of 200 V for 30 seconds. Then, the second insulating material 106 was formed by electrodeposition, dried at 190 ° C. for 10 minutes, softened, dissolved, and leveled to form the second insulating material 106 having a thickness of 30 μm. At the same time, integration with the first insulating material 104 was attempted.

  Thereafter, the masking tape was peeled off, nickel gold plating was applied to the terminal portion 111, and the outer shape was pressed to obtain a coil 120 having an outer diameter of 8.5 mm.

  Examples of the coil member 121 described above will be described below.

  In the substrate material corresponding to the insulating base material 102, which is obtained by bonding 18 μm of copper to both sides of a glass epoxy substrate having a thickness of 0.2 mm, a portion necessary for connection of the terminal portion of the coil formed on both sides, A hole for the through hole 113 is made. Thereafter, copper plating is formed at 25 μm by electroless copper plating and electrolytic copper plating including the holes. Next, the dry film is laminated, and the first conductor 103 is spirally formed on one surface of the substrate material by a photo-etching method in a spiral shape with a width of 100 μm and a conductor interval of 150 μm. Similarly, the first conductor 103 is spirally formed on the other surface of the substrate material for five revolutions with a width of 100 μm and a conductor interval of 150 μm.

  Thereafter, a dry film is laminated on both surfaces of the substrate material, and a masking dry film is developed and left on both ends 3 mm of the first conductor 103 on both surfaces of the glass epoxy substrate material by a photolithography method. Mask the terminal portions 111 on both sides of the material. Thereafter, a modified epoxy resin for electrodeposition coating is applied at a voltage of 200 V for 30 seconds, and the epoxy resin is electrodeposited on the exposed surfaces 103a of the first conductor 103 on both surfaces of the glass epoxy substrate material to form the first insulating material 104. To do. Thereafter, the first insulating material 104 is dried at 190 ° C. for 10 minutes, softened, melted, and leveled, and the film thickness 1032 of the flat portion 1031 of the first conductor 103 on both surfaces of the glass epoxy substrate material is 30 μm, and the rising portion 1034. A first insulating material 104 having a thickness of 25 μm was formed. Thereafter, the masking dry film of the terminal portion 111 is peeled off with chemicals, and then electroless copper plating is applied to both surfaces, and electroless copper plating on the surface other than the portion to be the second conductor 105 is performed by a photoetching method. Etch away. Next, 18 μm of electrolytic copper plating is applied to the remaining electroless copper plating portion, and the second conductor 105 is spirally formed with a width of 100 μm for 4.5 revolutions. Thereafter, the exposed surface 105a of the second conductor 105 is electrodeposited by applying a modified epoxy resin for electrodeposition coating at a voltage of 200 V for 30 seconds to form the second insulating material 106, and then dried at 190 ° C. for 10 minutes, The second insulating material 106 having a thickness of 30 μm was formed by softening, melting, and leveling. At the same time, integration with the first insulating material 104 was attempted.

  Thereafter, nickel gold plating was applied to the terminal portion 111, and the outer shape was pressed to obtain a coil 121 having an outer diameter of 9 mm.

  The present invention is applicable to a rigid or flexible circuit wiring board and a manufacturing method thereof.

It is sectional drawing of the circuit wiring board which is embodiment of this invention. It is a figure which shows the manufacturing process of the circuit wiring board shown in FIG. It is a flowchart which shows the manufacturing process of the circuit wiring board shown in FIG. It is an enlarged view of the 1st conductor part in the circuit wiring board shown in FIG. It is sectional drawing in the modification of the circuit wiring board shown in FIG. It is a top view of the circuit wiring board shown in FIG. It is sectional drawing in the II section shown in FIG. It is a top view in the modification of the circuit wiring board shown in FIG. It is a top view in another modification of the circuit wiring board shown in FIG. It is a top view in the other modification of the circuit wiring board shown in FIG. It is a top view of the coil which is another modification of the circuit wiring board shown in FIG. It is a top view in the modification of the coil shown in FIG. It is sectional drawing in another modification of the coil shown in FIG. It is sectional drawing in the modification of the coil shown in FIG. It is sectional drawing in the modification of the coil shown in FIG. It is sectional drawing in another modification of the coil shown in FIG. It is sectional drawing of the circuit wiring board which is a modification of embodiment of this invention shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Circuit wiring board, 102 ... Insulating base material, 103 ... 1st conductor, 103a ... Exposed surface,
104 ... first insulating material, 105 ... second conductor, 105a ... exposed surface,
106: second insulating material, 108: gap, 111: terminal portion.

Claims (8)

First wiring (114) formed by covering the first exposed surface (103a) of the first conductor (103) with the first insulating material (104) is formed on the conductor forming surface (102a) of the insulating base (102). For circuit wiring boards formed with a plurality of gaps (108),
Forming a second conductor (105) in the gap;
Forming a second insulating material (106) on the second exposed surface (105a) of the second conductor while fusing the first insulating material;
A method of manufacturing a circuit wiring board, comprising: Before the formation of the second conductor, the first conductor is formed on the conductor forming surface, and after the formation of the first conductor, the first insulating material is formed on the first exposed surface by an electrodeposition coating method,
The method for manufacturing a circuit wiring board according to claim 1, wherein after the formation of the first insulating material, the first insulating material is heated and softened to be in close contact with the conductor forming surface.   3. The method of manufacturing a circuit wiring board according to claim 1, wherein the second insulating material is formed on the second exposed surface by an electrodeposition coating method, and is fused with the first insulating material by heating after the formation.   The circuit wiring board manufacturing method according to claim 1, wherein the second insulating material is formed to cover the first insulating material and the second exposed surface.   The second conductor is formed of a thin film by any one of electroless plating, sputtering, and vacuum deposition after the first insulating material is formed on the first conductor, and the second conductor of the formed thin film is formed. The portion other than the portion necessary for formation is removed by photoetching or polishing, and then the portion necessary for forming the second conductor is formed by electroplating with a thickness different from that of the first conductor. The manufacturing method of the circuit wiring board in any one of 1-4.   The method for manufacturing a circuit wiring board according to claim 1, wherein the second conductor is formed of a material different from that of the first conductor.   A circuit wiring board manufactured by the method for manufacturing a circuit wiring board according to claim 1.   The circuit wiring board according to claim 7, wherein the first conductor and the second conductor are formed in a spiral shape to constitute a coil.

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