JP2007311778A - Method of manufacturing circuit board, circuit board manufactured thereby, and apparatus for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the occurrence of disconnection and short circuit caused by an emission failure and the like when a circuit pattern is formed by ejecting minute quantity of solution for conductive patterns and solution for insulating patterns with a liquid discharge head of an ink jet head shape. <P>SOLUTION: In a circuit pattern formation step, a preliminary discharging of a liquid discharge head (610E) for forming a circuit pattern is carried out to a portion (A1), where a circuit pattern (C1) does not exist and the preliminary discharging is carried out at intervals shorter than ejection interrupting time during which the emission failure may occur. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a circuit board widely used in electronic devices and the like, and a manufacturing apparatus and a manufacturing method for forming the circuit board.

  Circuit boards on which semiconductors such as LSIs and various electronic components are mounted are now widely applied as the core elements of various electronic devices, communication devices, computers, and the like. The circuit boards applied to these are mainly those using a composite material of a reinforcing material such as ceramic or glass fiber and a synthetic resin such as epoxy resin as a base material. However, in order to improve mountability in a limited space, circuit boards incorporated in small devices such as mobile phones and cameras should be flexible by using polyester resin or aramid resin as the base material. Some have done.

  Regarding circuit patterns formed on a circuit board, in most cases, one layer is formed on one or both sides of the board. However, at present, the mainstream is a multi-layer configuration such as 8 layers or 16 layers in accordance with the demands for downsizing the devices to be applied and increasing the density of the arrangement of the components. In addition, circuit patterns themselves are rapidly miniaturized and densified as electronic circuits become faster and smaller.

  Various methods have been put to practical use as circuit pattern forming methods on circuit boards, but the mainstream to date is the subtractive method. The subtractive method is a method of forming a circuit pattern by using a copper-clad laminate as a base material and removing unnecessary conductor portions by etching. However, the subtractive method includes many processes such as a hole making process on the base material, an electroless plating process, a patterning process using a dry film, an electrolytic plating process, an etching process, a solder peeling process, and the like. The ratio of processing costs to the cost increases. For this reason, this reduction in processing cost has been a major problem in manufacturing circuit boards. Further, since waste liquid is generated in the plating process and the etching process, waste liquid treatment for reducing the influence on the environment also becomes a problem.

  In order to solve these problems, Patent Document 1 and Patent Document 2 disclose a circuit board forming method that does not depend on the subtractive method. In these documents, a solution in which a conductive component is dissolved (conductive pattern solution) and a solution in which a conductive component is dissolved (insulating pattern solution) are mixed with a substrate by a liquid discharge head using an inkjet method. A method of forming a circuit board by discharging onto a surface is disclosed. Here, Patent Document 1 describes a method of forming a circuit board by alternately laminating conductive patterns and insulating patterns. On the other hand, in Patent Document 2, a conductive pattern solution and an insulating pattern solution are discharged together to form a circuit pattern layer composed of a conductive pattern and an insulating pattern, and a circuit pattern layer is similarly formed on the circuit pattern layer ( A method of forming a circuit board by stacking) is described.

  When a solution such as a conductive pattern solution or an insulating pattern solution is discharged by such a liquid discharge head (hereinafter also simply referred to as a head), there is no problem when the solution is continuously discharged from the nozzle of the head. However, in the case where the discharge of the solution is temporarily stopped and then restarted, there is a discharge failure such as a decrease in the speed or amount of the solution discharged from the nozzle or a change in the discharge direction. Non-ejection may occur. These discharge failures and non-discharges are caused by evaporation of the volatile components (solvents, etc.) in the solution by leaving the solution staying in the nozzle exposed to the outside air when the discharge is stopped, thereby increasing the viscosity of the solution. This is because it becomes difficult to discharge. In particular, in a circuit board manufacturing apparatus to which an on-demand ink jet method is applied, solution discharge from a nozzle may frequently stop depending on a pattern to be formed, and thus there is a sufficient risk that a discharge failure or the like will occur. is there. When a discharge failure or the like occurs, formation of a desired circuit pattern is hindered, and disconnection or a short circuit occurs.

  Therefore, it is desirable to remove the thickening solution staying in the nozzle and refill (refresh) the solution in a preferable viscosity range to the nozzle. For this reason, it is generally known to perform a discharge operation (second discharge operation) not related to pattern formation separately from the original discharge operation (first discharge operation) for forming a conductive pattern or an insulating pattern. This corresponds to an operation referred to as “preliminary discharge” in the ink jet recording technique, and the second discharge operation is hereinafter referred to as preliminary discharge for convenience. This preliminary discharge is conventionally performed in order to remove the thickening solution generated between the actual discharge of the solution and the start of the formation (drawing) of the circuit pattern. Proposals have been made.

  For example, in Patent Document 3, a preliminary discharge area is provided outside the pattern formation region, and preliminary discharge is performed on this area immediately before pattern drawing, thereby discharging the thickening solution and refilling the solution having a preferable viscosity. Thus, it is disclosed that discharge failure is avoided. In Patent Document 4, in the configuration in which preliminary discharge is performed during relative movement between the head and the work on which the pattern is formed, the preliminary discharge area is integrated with the work, and the pattern formation area and the preliminary discharge area are adjacent to each other as much as possible. The discharge failure is effectively prevented.

JP 2003-309369 A JP 11-163499 A JP 2003-282245 A JP 2004-81988 A

  In recent years, when electronic circuits have been highly integrated, the density of circuit boards has been rapidly increasing, and it is essential to make circuit patterns even thinner. For this purpose, it is necessary to reduce the discharge amount per dot of the conductive pattern solution and the insulating pattern solution discharged from the head. In order to reduce the discharge amount, it is effective to reduce the nozzle tip diameter. However, if the nozzle tip diameter is reduced, a discharge defect or the like due to the thickening of the solution in the nozzle is more likely to occur. In particular, in the case of a head that ejects droplets of several pl to several tens of pl, which is likely to be used for forming a circuit board having a high-density pattern, it is only necessary to stop ejection for about 50 to 100 milliseconds. It has been confirmed that a discharge failure occurs.

  FIG. 20 is a schematic view of a circuit board formed by discharging a conductive pattern solution with a head. A head 1 formed by arranging a plurality of nozzles 2 moves a conductive pattern solution onto a substrate 3 while moving in a direction indicated by an arrow M that is different from the nozzle arrangement direction from the illustrated position. Form. In the case of the configuration shown in this figure, the vertical dimension of the substrate 3 is larger than the nozzle arrangement width. Therefore, while the head 1 is returned to the original predetermined position, the substrate 3 is moved by the nozzle arrangement width in the arrow S direction orthogonal to the head moving direction (M direction), and then the head 1 is moved again in the M direction. By forming the conductive pattern portion, the conductive pattern is formed on the entire surface of the substrate 3.

  In the conductive pattern formation region, there are a region A where no conductive pattern exists, a region B for mounting an electrical component such as an IC, and the like. In the region A, the discharge of the conductive pattern solution may stop while the head passes therethrough, that is, for several tens to several hundreds of milliseconds. Therefore, particularly when a head that discharges micro droplets is used, when the next conductive pattern portion C is formed, ejection failure may occur due to the thickening solution staying in the nozzle.

  As described above, in the formation of the circuit board, there is a possibility that ejection failure may occur even during the operation of forming the circuit pattern. For this reason, as described in Patent Document 3 and Patent Document 4, ejection failure cannot be effectively prevented only by preliminary ejection performed before pattern formation, and a highly reliable circuit board can be formed. become unable.

  The present invention has been made in view of the above-mentioned problems, and when a circuit pattern is formed by discharging a minute amount of solution with a liquid discharge head, occurrence of disconnection or short circuit due to discharge failure or the like is prevented. Accordingly, it is an object to provide a highly reliable and high-density circuit board.

For this purpose, the present invention uses a head that can move relative to a base material, and discharges a solution into a region where a circuit is formed on the base material, thereby forming a pattern for the circuit in the region. A circuit board manufacturing method for forming
A step of performing a first discharge operation for forming the pattern on the substrate by the head;
A step of performing a second discharge operation not related to the pattern formation for keeping the discharge performance in a good state by the head, and
In the course of the first discharge operation, when there is a discharge interruption time that may cause discharge failure, the second discharge is directed toward a range where the pattern formed by the first discharge operation in the region does not exist. It is characterized by performing an operation.

Further, the present invention uses a head that is relatively movable with respect to the substrate, and discharges a solution into an area where a circuit is formed on the substrate, whereby a pattern for configuring the circuit in the area is formed. A circuit board formed,
The pattern formed by the first ejection operation of the head on the substrate;
In order to keep the ejection performance of the head in a good state, a pattern that is formed by a second ejection operation not related to pattern formation of the circuit and does not constitute the circuit;
The pattern that does not constitute the circuit constitutes the circuit formed by the first ejection operation in the region when there is an ejection interruption time during which the ejection failure may occur in the process of the first ejection operation. It is characterized in that it is formed in a range where there is no pattern for doing so.

Furthermore, the present invention uses a head that can move relative to a base material, and discharges a solution into a region where a circuit is formed on the base material, thereby forming a pattern for forming the circuit in the region. A circuit board manufacturing apparatus for forming
Means for causing the head to perform a first discharge operation for forming the pattern on the substrate and a second discharge operation not related to the pattern formation for maintaining a good discharge performance;
In the course of the first discharge operation, when there is a discharge interruption time that may cause discharge failure, the second discharge is directed toward a range where the pattern formed by the first discharge operation in the region does not exist. Means for performing the action;
It is characterized by having.

  In the present invention, in the process of forming the circuit pattern by the first discharge operation of the head, the second discharge operation (preliminary discharge) that is not related to the circuit pattern is performed in a portion where the circuit pattern does not exist. In addition, the preliminary ejection is performed at intervals less than the ejection interruption time at which ejection failure may occur. Thereby, it is possible to effectively prevent the circuit pattern from being disconnected or short-circuited due to ejection failure. In addition, since preliminary ejection can be performed simultaneously in the circuit pattern formation process, throughput is improved.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

(Configuration example of circuit board manufacturing equipment)
FIG. 1 is a schematic perspective view showing a mechanical configuration example of a circuit board manufacturing apparatus to which the present invention can be applied, and FIG. 2 is a block diagram showing a configuration example of its control system.

  On the carriage 109, two heads 610E and 610I (not shown in FIG. 1) for discharging the conductive pattern solution and the insulating pattern solution onto the substrate 3 are mounted. As these heads 610E and 610I, those in which nozzles are arranged in a direction different from the moving direction (M direction) of the carriage 109 on the surface facing the substrate 3 can be used. In the following, these two heads 610E and 610I are referred to as a conductive pattern solution discharge head (corresponding to the first head) and an insulating pattern solution discharge head (corresponding to the second head), or simply as a head, respectively. To tell.

  The carriage 109 can be equipped with two tanks for supplying the conductive pattern solution and the insulating pattern solution to the heads 610E and 610I, respectively. These tanks may be mounted on the carriage 109 and integrated with the head, or may be provided at a fixed portion of the apparatus to supply a solution to each head via a tube or the like.

  Here, as the conductive pattern solution, a solution containing a metal colloid such as Al, Ag, SnO2 is generally used from the viewpoint of conductivity, and the particle diameter of the metal colloid is the uniformity and stability of the circuit pattern. The thing of the range of several 10 to several 100 nm is suitable from such viewpoints. As the insulating pattern solution, those containing insulating fine particles such as silica, alumina, calcium carbonate and magnesium carbonate are preferably used. However, the insulating pattern solution is not particularly limited as long as it finally exhibits insulating properties. It is not a thing. Examples of the material of the base material 3 include porous ceramics obtained by sintering alumina, silica, aluminum nitride, barium titanate, zirconia, etc., porous resin films mainly made of polyolefin or inorganic filler, glass fibers, and the like. . However, in this embodiment, since it has a heat fixing step and a firing step as described later, it is desirable to use heat-resistant porous ceramics.

  The carriage 109 can be moved in the M direction in the figure by a driving means (hereinafter referred to as a CR linear motor) 101 in the form of a linear motor, for example, on a stage 103 on which the substrate 3 is mounted. On the other hand, the stage 103 can be moved in the S direction in the drawing orthogonal to the moving direction of the carriage 109 by a driving means (hereinafter referred to as LF linear motor) 102 in the form of a linear motor, for example.

  The LF linear motor 102 is fixed to the surface plate 108 with high rigidity, and the surface of the stage 103 on which the substrate 3 is placed is always kept parallel to the surface of the surface plate even when the stage moves. The CR linear motor 101 is fixed on the surface plate 108 with high rigidity via the bases 104 and 105, and the carriage 109 is adjusted so as to move parallel to the surface of the surface plate, that is, the surface of the stage 103.

  The CR linear motor 101 and the LF linear motor 102 are respectively provided with linear encoders 111 and 112 and origin sensors 106 and 107, which are used as servo control inputs when driving the linear motors. The output of the linear encoder 111 is also used for controlling the discharge timing of the conductive pattern solution discharge head 610E and the insulating pattern solution discharge head 610I. If a linear encoder having a high resolution of about 0.5 μm is used, it is sufficient to form a circuit pattern with a width of several tens of μm.

  The stage 103 supporting the base material 3 can be one in which a heater 620 is embedded. Accordingly, by heating the formed circuit pattern, evaporation of the solvent, that is, fixing of the circuit pattern can be promoted. Note that a temperature sensor for temperature adjustment may be provided in association with the heater 620.

  In FIG. 2, reference numeral 605 denotes a motor driver for driving the CR linear motor 101 and the LF linear motor 102, and 606 denotes a head driving circuit device for driving the heads 610E and 610I. Reference numeral 607 denotes an input / output (I / O) port for receiving signal inputs from the encoders 111 and 112 and the origin sensors 106 and 107 and outputting a drive signal to the heater 620.

  Reference numeral 600 denotes an MPU that controls each unit of the apparatus, and executes a control program corresponding to the control procedure described later with reference to FIG. 6, FIG. 10 or FIG. 19 stored in the program ROM 601 while appropriately using the work RAM 602. . A communication control driver 604 is connected to a computer-type host device 1000 and receives drawing data of a circuit pattern to be formed from the host device 1000 and transmits a status of the circuit board manufacturing apparatus to the host device 1000. The drawing data is developed in the VRAM 603 corresponding to the position on the substrate 3, and based on this, the ejection operation of the heads 610E and 610I and the movement operation of the carriage 109 and the stage 103 are controlled.

That is, based on the circuit pattern drawing data,
An operation of moving the stage 103 to a predetermined position by the LF linear motor 102, and then, a carriage 109 is scanned by the CR linear motor 101, and the heads 610E and 610I are driven in the process to reach a predetermined position on the substrate 3. An operation of discharging the conductive pattern solution and the insulating pattern solution is performed. By repeating these operations as many times as necessary, a circuit pattern composed of a conductive pattern and an insulating pattern can be formed on the substrate 3.

  In the circuit board manufacturing apparatus of this example, since the formed circuit pattern can be quickly fixed by the heater 620, the circuit pattern is continuously laminated on the fixed circuit pattern. A multilayer circuit board having a laminated structure can be formed. However, in the formed circuit pattern, the solvent contained in each solution remains, and the metal colloid for developing conductivity exists as it is. Therefore, with regard to electrical insulation and conductivity, in order to further improve the performance of the circuit board, the solvent in the formed circuit board is completely removed, and the metal colloid is sintered to develop conductivity. Therefore, it is desirable to perform the baking process using a separately provided baking apparatus.

  Hereinafter, several embodiments suitable for achieving the intended object of the present invention for preventing ejection failure during circuit pattern forming operation will be described for the circuit board manufacturing apparatus having the above-described configuration. These embodiments are characterized in that preliminary ejection is performed in the process of forming a circuit pattern. However, when preliminary ejection is performed prior to circuit pattern formation, Japanese Patent Application Laid-Open No. 11-163499 and Japanese Patent Application Laid-Open No. 2004-81988. It is possible to apply the technology described in the publication.

(Embodiment 1)
3A to 3C (hereinafter corrected in the same manner) are schematic diagrams of three consecutive layers when conductive pattern layers and insulating pattern layers are alternately laminated on a substrate. Here, FIGS. 3A and 3C are the upper and lower insulating pattern layers sandwiching the conductive pattern layer of interest (FIG. 3B), respectively. In order to obtain a circuit board having such a multilayer structure, the formation data of the conductive pattern solution and the formation data of the insulating pattern solution may be sequentially applied in the above device configuration.

  3A and 3C showing the insulating pattern layer, the hatched portion 5 represents the insulating pattern, and the white circle portion 6 'represents the via hole. Further, in FIG. 3B showing the conductive pattern layer, a portion 4 indicated by a solid line and a black circle represents a conductive pattern, and a broken line portion represents a portion to which a conductive pattern solution is not applied for mounting an IC or the like.

  The insulating pattern layer on the upper layer or the lower layer of the conductive pattern layer needs to be insulated from the conductive pattern 4 except for the via hole 6 ′ for conducting with the conductive pattern layers stacked above and below the conductive pattern layer. Therefore, as shown in FIGS. 3A and 3C, the insulating pattern solution is applied so as to obtain a “solid” pattern except for the portion of the via hole 6 ′. That is, when the insulating pattern layer is formed, the insulating pattern solution is almost continuously discharged, so that the discharge failure of the insulating pattern solution discharge head 610I does not occur during the circuit pattern forming operation.

  On the other hand, in the conductive pattern layer (FIG. 3B), there are no conductive patterns 4 or sparse areas A1 and B1. Accordingly, since the discharge of the conductive pattern solution discharge head 610E is temporarily interrupted in these regions, there is a possibility that a discharge failure may occur in the conductive pattern portion C1 where discharge is resumed next time.

  In view of this, the inventors paid attention to the insulating pattern layers above and below the conductive pattern layer and adopted a new preliminary discharge method. As described above, since the insulating pattern 5 is a “solid” insulating pattern except for the via hole 6 ′, the conductive pattern 4 is completely insulated except for the portion of the via hole 6 ′. Therefore, as shown in FIG. 4, it is possible to perform preliminary discharge of the conductive pattern solution as long as it is within a range (shaded portion in the figure) that is more than a distance that can be electrically separated from the conductive pattern 4. It is. That is, the conductive pattern formed by the preliminary ejection is not particularly problematic because it is electrically independent from the original conductive pattern. Here, the “electrically separable distance” means the electrical characteristics of the circuit board, that is, a distance that satisfies standards such as insulation resistance and withstand voltage. If this distance satisfies this, it will not be a problem on the performance of the circuit board. In addition, the range in which the preliminary ejection can be performed refers to a range surrounded by a pattern for forming a circuit (in this embodiment, a conductive pattern such as the portion C1), but is completely, that is, surrounded by a gap. You don't need to be.

  Here, an important thing as an electrical characteristic of the circuit board is an insulation resistance between wirings. The distance between two wirings necessary to satisfy the standard value of insulation resistance varies greatly depending on the state of the wiring, the potential difference between the wirings, the physical properties (insulation resistance, surface resistance) of the insulation pattern, and the like. For example, the appropriate distance between the wirings varies depending on whether the wiring is exposed as in the surface pattern layer or whether it is covered with the insulating pattern as in the inner layer pattern. In a very general circuit board, a distance between wirings of 100 μm or more is sufficient. Compared to the distance between the wires, the distance that the carriage moves in the discharge interval (discharge stop time) at which discharge failure may occur is large. In a head having a discharge amount of 1 to 10 pl as used in this embodiment, a discharge interruption time in which a discharge failure occurs is about 10 msec to 300 msec. If the carriage on which this head is mounted is scanned at 0.05 to 1 m / s, the distance that the carriage moves at a discharge interval (discharge stop time) at which discharge failure may occur is at least 500 μm. This is greater than a distance of 100 μm that satisfies the electrical characteristics. Therefore, in the present embodiment, the “electrically separable distance” is determined based on the distance at which ejection failure does not occur in the head actually used, and preliminary ejection is performed. In this embodiment, the distance is set to 200 μm in consideration of a margin of 100 μm. However, an optimum distance may be set in consideration of the characteristics of the insulating pattern.

  FIG. 5 shows a pattern finally obtained when the original conductive pattern is formed and the preliminary discharge is performed within the range shown in FIG. 4, that is, the conductive pattern solution is actually discharged. The pattern is shown. Here, for the sake of clarity, only the region A1 and its vicinity in FIG. In this example, the plurality of nozzles 2 arranged in the head 610E are divided into an odd-numbered nozzle group and an even-numbered nozzle group from one end of the arrangement range, and are preliminarily discharged from these alternately in the area A1. A staggered pattern as shown is formed.

  Here, the reference is determined so that the preliminary discharge interval of the odd-numbered nozzle group and the preliminary discharge interval of the even-numbered nozzle group are set to a time shorter than the time when the solution in the nozzle thickens and discharge failure occurs. . Therefore, the conductive pattern solution in each nozzle continues to be refreshed in the region A1, and the ejection performance is always kept stable and good. In addition, the reference is determined so that the interval from the last preliminary discharge in the region A1 to the discharge of the next conductive pattern C1 is set to a time shorter than the time when the discharge failure occurs. Therefore, since discharge is normally performed in the conductive pattern C1, no disconnection or short circuit occurs in the conductive pattern C1.

  In addition, since preliminary ejection can be performed simultaneously in the circuit pattern formation process, throughput is improved. Furthermore, there is no need to provide a preliminary discharge area adjacent to the pattern formation area on the base material or workpiece, or even if this preliminary discharge area is provided, this can be minimized, so the size of the base material can be flexibly changed. It can correspond to.

FIG. 6 is a flowchart showing a control procedure for realizing the above operation.
First, the drawing data of the conductive pattern of the target layer is read (step S1), and based on this, a range that is electrically separated from the conductive pattern is set as a preliminary dischargeable range (step S2). Next, staggered preliminary ejection pattern data that satisfies the above-described criteria is generated from the preliminary ejection range (step S3). Then, by calculating the logical sum of the conductive pattern data (original conductive pattern) read in step S1 and the preliminary discharge pattern data generated in step S3, the actual discharge pattern data defining the actual discharge operation is obtained. Generate (step S4). For these operations, the area of the VRAM 603 can be used as appropriate.

  Then, the head 610E is driven in accordance with the actual discharge pattern data to discharge the conductive pattern solution (step S5), whereby the conductive pattern shown in FIG. 5 is obtained.

  Note that the preliminary ejection pattern (pattern not constituting a circuit) is not limited to that shown in FIG. 5, and the thickening solution accumulated in the nozzle until the next conductive pattern C <b> 1 is ejected. Anything that can be removed is acceptable.

  FIG. 7 is a diagram showing an example thereof, and is an enlarged view of the area A1 and its vicinity in FIG. In this example, preliminary discharge is performed from all the nozzles immediately before the next conductive pattern C1 to form a “solid” pattern, thereby removing all the thickening solution that remains, and immediately thereafter, the conductive pattern C1. Discharging is performed. In this case, the same effect as described above can be obtained. The procedure for forming the preliminary ejection pattern in this case can be the same as the procedure shown in FIG. That is, in step S3, instead of using the staggered pattern as the preliminary ejection pattern, if an image having a “solid” pattern with a predetermined width from the edge portion in the head scanning direction of the preliminary ejection possible range is used as the preliminary ejection pattern, FIG. Can be obtained.

  Moreover, this embodiment illustrated the case where a circuit board was formed by alternately laminating conductive pattern layers and insulating pattern layers. However, the present invention has a basic feature in that preliminary ejection is performed in the process of forming a circuit pattern for the purpose of preventing ejection failure during the circuit pattern forming operation. That is, it does not matter whether the circuit board has a single layer configuration or a multilayer configuration. Therefore, for example, it is effective to apply this embodiment to a circuit board in which only one conductive pattern layer as shown in FIG. 3B is formed on a base material. In short, if there is a part where the conductive pattern does not exist in the conductive pattern layer and there is a range that is separated from the conductive pattern by more than the distance that can be electrically separated, the range is defined as the pre-dischargeable range of the conductive solution. Preliminary discharge can be performed.

(Embodiment 2)
Next, an embodiment in which a circuit board is formed by laminating a circuit pattern layer on which a conductive pattern and an insulating pattern are formed by discharging both a conductive pattern solution and an insulating pattern solution to one layer will be described. To do.

  FIGS. 8A to 8C are schematic views showing three continuous circuit pattern layers when a plurality of circuit pattern layers having both the conductive pattern 4 and the insulating pattern 5 are laminated on the base material 3. . In the present embodiment, the entire region of each circuit pattern layer is filled with the conductive pattern 4 and the insulating pattern 5. The insulating pattern occupies most of the area of the circuit pattern layer of the target layer (FIG. 8B) and the upper and lower layers (FIGS. 8A and 8C). The ejection failure of the liquid solution ejection head 610I does not occur.

  On the other hand, in the conductive pattern portion of the target layer, as in the first embodiment, there are no conductive patterns 4 or sparse regions A2 and B2. Accordingly, since the discharge of the conductive pattern solution discharge head 610E is temporarily interrupted in these regions, there is a possibility that a discharge failure may occur in the conductive pattern portion C2 where discharge is resumed next.

  On the other hand, the upper and lower two layers sandwiching the target layer are all “solid” insulating patterns except for the connection portion 6 which is a conductor portion connecting between the conductor patterns of each circuit pattern layer. All parts except the part 6 are completely insulated. Therefore, as in the first embodiment, as shown in FIG. 4, if the conductive pattern solution is preliminarily discharged within a range that is at least a distance that can be electrically separated from the conductive pattern, There is no problem even if it is formed. Also in this embodiment, “electrically separable distance” has the same meaning as described in the first embodiment.

  FIG. 9 is an enlarged view of the vicinity of the area A2 in FIG. 8B when the preliminary discharge of the present embodiment is performed. In the present embodiment, the conductive pattern solution is partially reserved by the head 610E in the region A2 where the “solid” -shaped insulating pattern is to be formed by discharging the insulating pattern solution by the head 610I. There are staggered patterns formed by ejection.

  Also in this embodiment, the reference is set so that the preliminary discharge interval of the odd-numbered nozzle group and the preliminary discharge interval of the even-numbered nozzle group are set to a time shorter than the time when the solution in the nozzle thickens and discharge failure occurs. Is determined. Therefore, the conductive pattern solution in each nozzle continues to be refreshed in the region A2, and the ejection performance is always kept stable. In addition, the reference is determined so that the interval from the last preliminary discharge in the region A2 to the discharge of the next conductive pattern C2 is also set to a time shorter than the time when the discharge failure occurs. Accordingly, since the ejection is normally performed in the conductive pattern C1, no disconnection or short circuit occurs in the conductive pattern C2.

FIG. 10 is a flowchart showing a control procedure for realizing the above operation.
First, after reading the conductive pattern data of the target layer and the circuit patterns stacked above and below it (step S11), a range within the target layer that is electrically separated from the conductive pattern is set as a predischargeable range. (Step S12). Next, staggered preliminary ejection pattern data is generated in accordance with the above-mentioned criteria within the preliminary ejection possible range (step S13). Then, the logical sum of the conductive pattern data (original conductive pattern) read in step S11 and the preliminary ejection pattern data generated in step S13 is obtained. Thereby, actual ejection pattern data (data for forming a pattern as shown in FIG. 11A) that defines the actual ejection operation of the conductive pattern solution in the target layer is generated (step S14). . Furthermore, data for the actual ejection pattern of the solution for insulating pattern as shown in FIG. 11B for filling the region other than the conductive pattern with the insulating pattern is generated (step S15). The generation of the actual discharge pattern data of the insulating pattern solution can be easily obtained, for example, by inverting the actual discharge pattern data of the conductive pattern solution. In the above operation, it is possible to appropriately use the area of the VRAM 603 and use data developed for each layer, and further for each conductive pattern or insulating pattern.

  Then, the heads 610E and 610I are driven in accordance with the actual discharge pattern data, and the conductive pattern solution and the insulating pattern solution are discharged, respectively (step S15), whereby the conductive pattern shown in FIG. 11A is obtained. .

  Note that the preliminary ejection pattern is not limited to that shown in FIG. 9 as long as the thickening solution accumulated in the nozzle is removed before the next conductive pattern C2 is ejected. Good.

  FIG. 12 is a diagram showing an example thereof, and is an enlarged view of the area A2 in FIG. 8B and the vicinity thereof as in FIG. In this example, preliminary ejection is performed from all nozzles of the head 610E immediately before the next conductive pattern C2 to form a “solid” pattern, thereby removing all the thickening solution that has remained, and immediately thereafter conducting the conductive pattern. The pattern C2 is ejected. In this case, the same effect as described above can be obtained. The procedure for forming the preliminary ejection pattern in this case can be the same as the procedure shown in FIG. That is, in step S13, if the preliminary ejection pattern data having a “solid” pattern with a predetermined width is generated from the edge portion in the head scanning direction of the preliminary ejection possible range, the pattern shown in FIG. 12 can be obtained.

(Embodiment 3)
In the present embodiment, as in the second embodiment, the circuit pattern layer in which the conductive pattern and the insulating pattern are formed by discharging both the conductive pattern solution and the insulating pattern solution to one layer is laminated to form a circuit board. Applicable when forming. However, in this embodiment, attention is paid to the circuit pattern layer forming the connection portion.

  FIGS. 13A to 13C are schematic diagrams showing three continuous circuit pattern layers when a plurality of circuit pattern layers having both the conductive pattern 4 and the insulating pattern 5 are laminated on the base material 3. . In the target layer shown in FIG. 13B, the connection portion 6 is a part of the conductive pattern 4, and the rest is the insulating pattern 5. Therefore, even if an attempt is made to form scattered connection portions as shown in this circuit pattern, there may occur a case where the connection portions cannot be formed due to ejection failure in the head 610E.

  Accordingly, the inventor paid attention to the relationship between the target layer and the upper and lower layers sandwiching the target layer (FIGS. 13A and 13C) and adopted a new method for pre-discharge of the conductive pattern solution. In the target layer, the region other than the connection portion is an insulating layer provided to insulate the upper and lower layers, and in fact, it is not necessary that the entire region be an insulating pattern. This is because, when it is assumed that there is no target layer, the short circuit occurs between the upper and lower two layers only in the portion where the upper and lower conductive patterns overlap.

  FIG. 14A is a diagram in which the upper and lower conductive patterns are overlapped, and the upper and lower conductive pattern portions intersect or the adjacent portions overlap each other as shown by the broken line. It is. As used herein, “overlapping portion” means that when the upper and lower layers are directly stacked, the distance between the conductive patterns is less than the electrically separable distance, that is, the electrical characteristics (insulation resistance, (Withstand voltage, etc.) is close to a distance that does not satisfy the specifications of the circuit board. In such a case, if the conductive pattern exists within a predetermined distance from the portion in the target layer corresponding to the overlapping portion, a short circuit occurs between the upper and lower conductive patterns. In other words, it is possible to appropriately avoid the portion in the target layer corresponding to the overlapping portion, and to pre-discharge the conductive pattern solution to form a conductive pattern at a portion that is a predetermined distance away from the portion. . The “predetermined distance” means “an electrically separable distance” as described above. Further, since the conductive pattern solution cannot be preliminarily discharged within a predetermined distance from the connection portion in the target layer, this region should be appropriately avoided.

  FIG. 14B shows a region (shaded portion) where the conductive pattern solution of the target layer determined for the target layer of FIG. 13B can be preliminarily discharged through the above consideration. As for the preliminary discharge pattern of the conductive pattern solution formed here, the preliminary discharge of the conductive pattern solution is performed on the insulating “solid” pattern portion as in the second embodiment. Or a “solid” pattern as shown in FIG. In short, if the thickening solution staying in the nozzle is removed before the discharge of the original conductive pattern portion to be formed next, it is possible to effectively prevent the defective formation of the connecting portion due to the discharge failure. . The ejection pattern generation method is the same except that the preliminary ejection range is different.

FIG. 15 is a flowchart showing a control procedure for realizing the operation of the present embodiment.
First, after reading the conductive pattern data of the circuit patterns stacked above and below the target layer (step S21), a portion where the conductive patterns of the upper and lower layers overlap is obtained (step S22). Next, after reading the conductive pattern of the target layer (step S23), the region A is determined from the logical sum of the previously obtained overlapping portion data and the conductive pattern data of the target layer (step S24). Then, a range that is electrically separated from the region A is set as a preliminary dischargeable range (step S25). Next, preliminary ejection pattern data for filling the preliminary ejection range with, for example, a staggered pattern according to the same standard as described above is generated (step S26). Next, discharge pattern data for actually discharging the conductive pattern solution to the target layer is generated from the logical sum of the conductive pattern of the target layer read in Step S23 and the preliminary discharge pattern obtained in Step S26 (Step S23). S27). Further, actual ejection pattern data for actually ejecting the insulating pattern solution to other portions is obtained (step S28). The generation of the actual discharge pattern data of the insulating pattern solution can be easily obtained, for example, by inverting the actual discharge pattern data of the conductive pattern solution. In these operations, the region of the VRAM 603 is appropriately used, and data developed for each layer, and further for each conductive pattern or insulating pattern can be used.

  Then, the heads 610E and 610I are driven in accordance with these actual ejection pattern data, and the desired pattern is obtained by ejecting the conductive pattern solution and the insulating pattern solution, respectively (step S29).

(Embodiment 4)
In the present embodiment, attention is paid to a circuit pattern layer for connecting to a power source or a ground. Here, it is assumed that a circuit board is formed by laminating a circuit pattern layer in which a conductive pattern and an insulating pattern are formed by discharging both a conductive pattern solution and an insulating pattern solution to one layer.

  FIGS. 16A to 16C are schematic views showing three continuous circuit pattern layers when a plurality of circuit pattern layers are stacked on the substrate 3. FIG. 16B shows a target layer of this example, which is a circuit pattern layer for connecting to a power source or a ground, and is sandwiched between two upper and lower circuit pattern layers (FIGS. 16A and 16C). It is. This layer of interest is divided into three power planes 8 (conductive “solid” patterns) by a linear insulating pattern 5. Therefore, in this target layer, there is a risk that ejection failure of the head 610I may occur when attempting to form a linear insulating pattern.

  Therefore, the inventor pays attention to the relationship between the target layer (FIG. 16B) and the upper and lower two layers (FIGS. 16A and 16C) sandwiching the target layer, and a new method for preliminarily discharging the insulating pattern solution. It was adopted. Since the target layer is a layer for power supply and ground connection, the connection portion 6 is provided in the upper and lower circuit patterns with respect to the power plane 8. Since the connection portion of the target layer is connected to the upper and lower layers, it is impossible to replace it with an insulating pattern. However, there is no problem even if the other portion is replaced with an insulating pattern as long as it satisfies the electrical characteristics as a power plane. Therefore, the range in which the insulating pattern solution can be preliminarily discharged in the target layer is a hatched portion shown in FIG. However, it must meet the electrical characteristics of the power plane. Therefore, in this embodiment, the preliminary discharge pattern of the insulating pattern solution is formed as a dispersion pattern. Specifically, by simultaneously driving a plurality of nozzles every predetermined number (for example, four) in the arrangement direction and driving every four dots (for example) in the scanning direction while shifting the simultaneous driving unit, A dispersion pattern as shown in FIG. With such a pattern, the power supply plane is not electrically disconnected, and electrical characteristics such as the allowable current and voltage drop of the power supply plane, which are standards in the specifications of the circuit board, can be satisfied.

FIG. 19 is a flowchart showing a control procedure for realizing the operation of this embodiment.
First, after reading the conductive pattern data of the circuit pattern layers stacked above and below the target layer (step S31), a connection portion is detected from each conductive pattern, and a portion other than the connection portion is set as a preliminary dischargeable range. (Step S32). Next, preliminary discharge pattern data of an insulating pattern solution for filling the preliminary discharge range with the dispersion pattern according to the above-described standard is generated (step S33). Next, after reading the insulation pattern data of the target layer (step S34), the logical sum of the insulation pattern data and the preliminary ejection pattern data is obtained, and an actual pattern for forming an insulation pattern as shown in FIG. Discharge pattern data is generated (step S35). Next, actual ejection pattern data for forming a conductive pattern as shown in FIG. 18B is generated from other portions (step S36). The generation of the actual discharge pattern data of the conductive pattern solution can be easily obtained, for example, by inverting the actual discharge pattern data of the insulating pattern solution. Of course, for example, the area of the VRAM 603 can be appropriately used for these operations.

  Then, the heads 610E and 610I are driven in accordance with the actual discharge pattern data, and the desired pattern as shown in FIG. 18C is obtained by discharging the conductive pattern solution and the insulating pattern solution, respectively (step S37). Will be obtained.

  As described above, in this embodiment, the dispersion pattern as shown in FIG. 18A is adopted within the preliminary discharge range shown in FIG. 17 to perform preliminary discharge of the insulating pattern solution. As a result, the discharge interval for each nozzle of the solution discharge head for the insulation pattern can be made shorter than the time when the solution in the nozzle thickens and discharge failure occurs, and a short circuit between the power planes caused by the insulation pattern failure is prevented. It can be effectively prevented.

(Other)
In the above embodiment, the circuit board manufacturing apparatus including the carriage 109 that moves with the heads 610E and 610I mounted thereon and the stage 103 that moves while holding the base material is used. However, it is also possible to use a circuit board manufacturing apparatus in which one of the heads 610E and 610I and the base material is fixed and the other is relatively movable in two dimensions. Further, not a so-called serial scan type apparatus such as these, but a line type having means for moving the substrate relative to this head using a head provided with nozzles over a range corresponding to the width of the substrate. It is also possible to use this device.

  In addition, the preliminary discharge of the conductive solution to the placement areas A1 and B1 such as the IC chip as shown in FIG. 3B is problematic if the placement area and the mounting surface of the chip (the surface in contact with the placement area) are insulative. Can be done without. That is, by performing preliminary discharge of the conductive solution on the region, a pattern that does not constitute a circuit can be formed, and a chip can be placed on the pattern. For example, a capacitor has an insulating property other than its electrode portion, and therefore it is possible to perform preliminary discharge of a conductive liquid solution to a portion where the capacitor is disposed. Further, when the insulating solution is preliminarily discharged in such an arrangement region, the arrangement region and the electrode portion of the chip may be prevented from being blocked. Further, in the case where the chip mounting surface is not in contact with the arrangement area, it is possible to perform preliminary discharge to the chip arrangement area without any problem, whether it is a conductive solution or an insulating solution.

It is a typical perspective view which shows the mechanical structural example of the circuit board manufacturing apparatus which can apply this invention. It is a block diagram which shows the structural example of the control system of the circuit board manufacturing apparatus of FIG. (A)-(c) concerns on the 1st Embodiment of this invention, and is a schematic diagram of 3 continuous layers at the time of laminating | stacking a conductive pattern layer and an insulating pattern layer on a base material alternately. It is a schematic diagram which shows the preliminary dischargeable range of the solution for conductive patterns on the attention layer according to the 1st Embodiment of this invention. FIG. 5 is a schematic diagram showing a pattern finally obtained when the original conductive pattern is formed and preliminary ejection is performed within the range shown in FIG. 4, and is a partially enlarged view of FIG. It corresponds. It is a flowchart which shows the control procedure for implement | achieving the operation | movement of 1st Embodiment. FIG. 5B is a schematic diagram showing a pattern finally obtained when the original conductive pattern is formed within the range shown in FIG. 4 and preliminary discharge different from FIG. 4 is performed. This corresponds to a partially enlarged view of. (A)-(c) is related with the 2nd Embodiment of this invention, and is a schematic diagram of 3 continuous layers at the time of laminating | stacking multiple circuit pattern layers which have both a conductive pattern and an insulating pattern on a base material. It is. FIG. 9 is an enlarged view showing the vicinity of a region A2 in FIG. 8B when preliminary discharge according to the second embodiment is performed. It is a flowchart which shows the control procedure for implement | achieving the operation | movement of 2nd Embodiment. (A) And (b) is a schematic diagram for demonstrating the operation | movement in the execution process of the procedure of FIG. FIG. 9 is an enlarged view showing the vicinity of a region A2 in FIG. 8B when preliminary ejection according to a modification of the second embodiment is performed. (A)-(c) is related with the 3rd Embodiment of this invention, and is a schematic diagram of 3 continuous layers at the time of laminating | stacking multiple circuit pattern layers which have both a conductive pattern and an insulating pattern on a base material. It is. (A) And (b) is a schematic diagram for demonstrating the determination aspect of the preliminary discharge possible range in 3rd Embodiment. It is a flowchart which shows the control procedure for implement | achieving the operation | movement of 3rd Embodiment. (A)-(c) is related with the 4th Embodiment of this invention, and is a schematic diagram of 3 continuous layers at the time of laminating | stacking a plurality of circuit pattern layers. It is a schematic diagram for demonstrating the determination aspect of the preliminary discharge possible range in 4th Embodiment. (A)-(c) is a schematic diagram for demonstrating the operation | movement in the execution process of the procedure of FIG. It is a flowchart which shows the control procedure for implement | achieving the operation | movement of 4th Embodiment. In order to explain the problem to be solved by the present invention, it is a schematic view of a circuit board formed by discharging a conductive pattern solution with an inkjet head.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,610E, 610I Liquid discharge head 2 Nozzle 3 Base material 4 Conductive pattern 5 Insulation pattern 6 'Via hole 6 Connection part 7 Overlap part 8 Power supply plane 101 CR linear motor 102 LF linear motor 103 Stage 104, 105 Base 106, 107 Origin sensor 108 Surface plate 109 Carriage 111, 112 Linear encoder 600 MPU
601 ROM
603 VRAM
1000 Host device (computer)

Claims (10)

Manufacture of a circuit board that uses a head that can move relative to a base material, and discharges a solution into an area where a circuit is formed on the base material, thereby forming a pattern for configuring the circuit in the area. A method,
A step of performing a first discharge operation for forming the pattern on the substrate by the head;
A step of performing a second discharge operation not related to the pattern formation for keeping the discharge performance in a good state by the head, and
In the course of the first discharge operation, when there is a discharge interruption time that may cause discharge failure, the second discharge is directed toward a range where the pattern formed by the first discharge operation in the region does not exist. A method of manufacturing a circuit board, comprising performing an operation.   The method for manufacturing a circuit board according to claim 1, wherein the circuit board has a laminated structure in which a plurality of the patterns are laminated. The solution includes at least one of a conductive solution for forming a conductive pattern and an insulating solution for forming an insulating pattern;
The pattern includes at least one of a conductive pattern and an insulating pattern,
The head includes at least one of a first head for discharging the conductive solution to form the conductive pattern and a second head for discharging the insulating solution to form the insulating pattern. Item 3. A method for manufacturing a circuit board according to Item 1 or 2. The head that performs the second ejection operation is the first head,
The method for manufacturing a circuit board according to claim 3, wherein the range in which the second ejection operation is performed is a range that is separated from the conductive pattern by a distance that is electrically separable.   5. The circuit according to claim 4, wherein the circuit board has a stacked structure in which a plurality of the patterns are stacked, and the range is insulated by insulating patterns of upper and lower layers corresponding to the range. A method for manufacturing a substrate. The head that performs the second ejection operation is the second head,
The circuit board has a laminated structure in which a plurality of the patterns are laminated,
The range in which the second ejection operation is performed is a portion other than the portion connected to the conductive pattern of the upper and lower layers corresponding to the range, and the second ejection operation is performed by the conductive pattern formed by the first head. 4. The method of manufacturing a circuit board according to claim 3, wherein the method is performed so as not to disturb the electrical characteristics of the circuit board. A circuit board on which a pattern for configuring the circuit is formed in the region by discharging a solution into the region where the circuit is formed on the substrate, using a head that can move relative to the substrate. There,
The pattern formed by the first ejection operation of the head on the substrate;
In order to keep the ejection performance of the head in a good state, a pattern that is formed by a second ejection operation not related to pattern formation of the circuit and does not constitute the circuit;
The pattern that does not constitute the circuit constitutes the circuit formed by the first ejection operation in the region when there is an ejection interruption time during which the ejection failure may occur in the process of the first ejection operation. A circuit board, wherein the circuit board is formed in a range in which no pattern is present.   The circuit board according to claim 7, wherein the range is a range surrounded by a pattern for configuring the circuit.   9. The circuit board according to claim 7, wherein a chip is arranged on a pattern that does not constitute the circuit. A circuit board that uses a head that can move relative to a base material, and discharges a solution into an area where a circuit is formed on the base material, thereby forming a pattern for configuring the circuit in the area. Manufacturing equipment,
Means for causing the head to perform a first discharge operation for forming the pattern on the substrate and a second discharge operation not related to the pattern formation for maintaining a good discharge performance;
In the course of the first discharge operation, when there is a discharge interruption time that may cause discharge failure, the second discharge is directed toward a range where the pattern formed by the first discharge operation in the region does not exist. Means for performing the action;
An apparatus for manufacturing a circuit board, comprising:

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