JP2006310872A - Manufacturing apparatus and method for manufacturing circuit forming substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing apparatus for manufacturing a circuit forming substrate with high reliability at low cost in which high positional precision can be achieved with high reproducibility, and to provide a method for manufacturing the circuit forming substrate using it. <P>SOLUTION: It is thought that the amount of the extension of a continuous PET film is changed by the friction coefficient of a first group roll. The friction coefficient is adjusted extremely small when a new film is used. It can be estimated that the amount of the extended PET film is stabilized by not changing the friction coefficient from a time when the film is new until the time of replacement. Particularly, the friction coefficient is not changed at the time of roll replacing, and a dimensional change is stabilized. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a manufacturing apparatus and a method for manufacturing a circuit forming substrate using the manufacturing apparatus.

  As electronic devices have become smaller and higher in density in recent years, the adoption of double-sided and multi-layer boards for circuit-forming boards on which electronic components are mounted has increased from the conventional single-sided board, and more circuits can be integrated on the board. A density circuit forming substrate is being developed.

  For high-density circuit-formed substrates, the use of laser processing methods that enable finer processing at higher speeds instead of drilling holes (through holes) that have been widely used in the past is being considered. (For example, Y. Yamanaka et al., Excimer Laser Processing In The Microelectronics Fields, etc.). There has also been proposed a circuit-formed substrate that performs interlayer connection using a fine hole drilling with a laser and connecting means such as a conductive paste (Japanese Patent Laid-Open No. 6-268345).

  In the technology of forming fine holes and connecting the layers using conductive paste, even if the laser processing machine has high-precision position processing capability, if the dimensions of the substrate itself shrink and fluctuate, the position between the layers An error occurs in the alignment, making the interlayer connection difficult.

  In the above-described conventional technique, the film is attached to the substrate material while applying a tensile tension so that the film does not wrinkle. Therefore, the substrate material is temporarily contracted due to the contraction stress of the film.

  Next, in this state, a via hole is formed in the substrate material together with the film by laser. This film serves as a mask when filling the fine holes with the conductive paste.

  After that, if the role as a mask is completed, the film is peeled off.

  As the film is removed, the shrinkage stress applied to the substrate is removed and the substrate material tries to return to its original size.

  It is difficult to obtain a highly accurate via hole position unless the function of expansion and contraction of the series of substrate materials is constant.

  As shown in the conventional circuit-forming board manufacturing apparatus of FIG. 9, as a method of applying tension to the film material, the leading small-diameter rolls 401a and 401b and then the large-diameter rolls 402a and 402b are connected by a driving belt, and one roller is used. By rotating in synchronization, a constant tension was obtained by utilizing the difference in outer circumference between the rolls.

  This method is very effective as an inexpensive and simple method for obtaining a constant tension.

  However, when the roll is new and when the roll is old, the friction coefficient on the roll surface is different, which causes a difference in the dimensional change of the substrate material as shown in FIG.

  In particular, when the roll is worn and replaced, a friction coefficient of about 1.7 is suddenly used even though a friction coefficient of 0.2 has been used so far, and the dimensional difference becomes large.

  Since the friction coefficient of the roll surface changes with time until the dimensional change is stabilized, the dimension is not stable immediately after the roll replacement as shown in the new roll area of FIG. 6 (for reference, the friction coefficient measurement of FIG. The film 303 used in this construction method is rolled to a roll 302 with an arbitrary length of 5 cm and is wound 90 °, and a weight 304 is hung at one end, and the other end is gently closed with a spring 301. The load (T) when the pulling film is moved is read and substituted into the equation shown in FIG. 8 to calculate μ (friction coefficient).

  In addition, the substrate material is attached to the film by heating and pressing, but after the attachment, the film with the substrate material attached to the third set of rolls 403a and 403b shown in FIG. Dimensional shrinkage is suppressed. However, when the film is continuously operated in a roll-to-roll manner, the third set of rolls 403a and 403b receive heat from the substrate material and become high temperature, and the temperature of the substrate material itself cannot be lowered.

Therefore, after passing between the third set of rolls 403a and 403b, the base material is softened, and the dancer roll 404 for adjusting the dimensional change of the substrate material arranged behind the third set of rolls 403a and 403b. As shown in FIG. 7, the dimensional change varies depending on the substrate material temperature. Therefore, it has been difficult to produce a highly accurate circuit forming substrate.
Y. Yamanaka et al. , Excimer Laser Processing In The Microelectronics Fields JP-A-6-268345

  As described above, the purpose of attaching the film to the substrate material is to use it as a mask film for filling a conductive paste for interconnecting circuits formed on the front and back surfaces or the inner layer of the substrate.

  In order to produce a high-density circuit-formed substrate in large quantities, the positional accuracy of the hole processing is very important, and a slight deviation greatly affects the connection reliability between layers. Therefore, it is necessary to reliably drill holes with high accuracy and high reproducibility.

  However, in the current method, there is a possibility that the change in the substrate dimension that occurs when the mask film and the substrate material are pasted, so there is a possibility that vias and lands may be shifted between layers when the circuit forming substrate is multilayered. Problems that adversely affect such as short-circuit between adjacent or open.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a circuit-formed substrate and a manufacturing apparatus therefor, which realizes a high-quality substrate material having fine holes and is low in cost and high in reliability.

In order to solve the above problems, the present invention is composed of a plurality of sets of rolls for attaching a film by passing a sheet-like workpiece between two upper and lower rolls, and at least a first set of rolls. A second set of rolls is provided behind the roll, and the first set of rolls has a stepped structure including an end portion and a portion through which a sheet-like workpiece passes, and the end of the first set of rolls The diameter is larger than the diameter of the portion through which the sheet-like workpiece passes and is the same as the diameter of the second set of rolls, and the outer periphery of the second set of rolls is the sheet shape of the first set of rolls. It is larger than the outer periphery of the part through which the workpiece passes, and the material of the first set of rolls is heat-resistant fluororubber,
A surface friction coefficient of the first set of rolls is 0.15 to 1.0, and the manufacturing apparatus is provided.

Moreover, the manufacturing method of the circuit formation board | substrate of this invention is continuously supplied to a 2nd set roll via the surface of the part through which the sheet-like workpiece of the 1st set roll of the manufacturing apparatus of Claim 1 passes. Pasting the film to be formed on both sides of the sheet-like substrate material, forming a through hole in the substrate material to which the film is pasted, filling the through hole with a conductive paste, and substrate the film A step of peeling from the material, a step of sandwiching the substrate material with a metal foil, heating and pressurizing it, and a step of forming a circuit of the metal foil, and a step of attaching a film to both sides of the substrate material includes: Operation to preheat the material and film-like material without applying pressure or adhesion, and the substrate material is not stretched, and the film-like material is stretched by a certain amount and heated and pressed to attach to the substrate material. It Ru step der kicking consisting of operation is that characterized. With this configuration, the tension applied to the film material in the pasting step of pasting the film-like material on one side or both sides of the substrate for substrate to form a substrate for film with film does not change even when the roll is replaced, By rapidly removing the temperature of the substrate material after the film is attached, a substrate material with a film having a stable dimensional change is obtained.

  According to this method, it is possible to provide a highly reliable circuit forming substrate at a low cost without losing laser processing position accuracy for high-quality hole processing.

  As described above, the variation of the substrate dimensional change can be eliminated by the circuit forming substrate manufacturing apparatus and the manufacturing method using the circuit forming substrate according to the present invention.

  In addition, by reducing the coefficient of friction of the roll from the time of using a new one, it is possible to suppress fluctuations in the dimensional change of the base material during use or replacement of the roll. It is possible to provide a method for manufacturing a highly reliable circuit-formed substrate having accurate dimensions.

  According to the first aspect of the present invention, the first set of rolls is a stepped roll having means for heating, the diameter of the end is large, and the part through which the workpiece passes has a small diameter. For this reason, since a certain gap can be formed in the part through which the workpiece passes when the upper and lower rolls come into contact with each other at the end of the roll, heat can be applied without compressing the workpiece.

  In addition, the roll material is heat-resistant fluororubber, so that the processing conditions can be raised to a high temperature, the processing speed is high, uniform pressure is applied to the work piece, and the physical properties of the roll surface are easily obtained. .

  Moreover, it has the effect | action which reproduces a fixed process condition and reduces the physical property fluctuation | variation of a roll over a long term.

  The second set of rolls has the same outer diameter as the larger diameter of the first set of rolls and has the ability to heat and press the object to be heated, and rotates in synchronization with the first set of rolls. By having a structure that obtains a peripheral speed difference from the narrow diameter portion of the first set of rolls, the stress applied to the workpiece is made constant.

The invention according to claim 2 of the present invention further facilitates the solidified suppress softening of the workpiece by cooling the temperature of the third pair of rolls to below the softening point of the adhesive contained in the workpiece This has the effect of suppressing the dimensional behavior of the workpiece.

  In addition, by flowing water through the third set of rolls, the temperature can be easily and effectively lowered, and by flowing water, it can be reused at low cost.

  Moreover, the manufacturing cost of an installation can also be reduced by using air as the fluid flowing in the third set of rolls.

  In the invention according to claim 3 of the present invention, the gap formed between the first set of rolls is a sheet-like structure having a gap larger than the total thickness of the sheet-like workpiece and the film. It has the effect of preheating without bonding the work piece and the film.

  The invention described in claim 4 of the present invention provides a method capable of surely synchronizing as means for rotating the first set of rolls and the second set of rolls in synchronization.

  Invention of Claim 5 of this invention has the effect | action which lowers | hangs the temperature of a workpiece reliably by providing the apparatus which applies the gas for cooling to a workpiece immediately after a 3rd set of roll.

  In the invention according to claim 6 of the present invention, the apparatus for producing a circuit-formed substrate according to the present invention is applied to an attaching step in which a film-like material is attached to one or both sides of a substrate substrate to form a substrate substrate with a film. By using it, it has the effect | action which can produce the highly accurate circuit formation board | substrate excellent in the dimensional accuracy.

  In addition, the substrate base material is a prepreg made by impregnating a thermosetting resin into a reinforcing material to form a B-stage, and the effect of heat is minimized even when the thermosetting resin contains an uncured part. It has the action that can be done.

  Further, the reinforcing material is a glass fiber woven fabric or a non-woven fabric, and has an effect of reducing unevenness of the inner wall of the hole due to a difference in processing rate between the thermosetting resin and the glass fiber.

  Furthermore, since the reinforcing material is an aromatic polyamide fiber woven fabric or non-woven fabric, the resin can be easily impregnated, and the thermosetting resin sufficiently B-staged can be held, so that the temperature characteristics of the resin can be easily used. Has an effect.

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  1 (a) to 1 (g) are process cross-sectional views of the method for manufacturing a double-sided circuit-formed substrate of the present invention.

  In FIG. 1A, reference numeral 1 denotes a substrate material as an insulating substrate having a 400 mm square and a thickness of about 150 μm. For example, a thermosetting epoxy resin is applied to a nonwoven fabric composed of aromatic polyamide fibers (hereinafter referred to as aramid fibers). A resin-impregnated base material made of a composite material impregnated (hereinafter referred to as an epoxy resin) is used.

  The epoxy resin is not completely cured, and the substrate material 1 in a so-called B-stage state including an uncured portion is usually called a prepreg.

  4a and 4b are releasable resin films having a thickness of about 20 μm with a Si-type release agent applied on one side, and for example, polyethylene terephthalate (hereinafter referred to as PET film) is used. Reference numerals 3a and 3b denote laminating rolls heated to a high temperature, and film lamination is performed by sandwiching and pressing the substrate material 1 sandwiched between the PET films 4a and 4b at about 130 ° C.

  The laminating apparatus of the present invention for attaching the PET films 4a and 4b to the substrate material 1 will be described in detail with reference to FIG.

  101a and 101b are rolls of continuous PET films (hereinafter referred to as PET rolls).

  The PET rolls 101a and 101b are attached to an unwinding shaft (not shown) and continuously supply a continuous PET film 120 to a laminating apparatus.

  102a and 102b are a first set of rolls made of fluororubber, and as shown in FIG. 4, the shape is a stepped roll having an outer diameter of 99.7 mm, the substrate material 1 and a continuous PET film 120. The portion through which is passed is a roll having an outer diameter of 99.0 mm, the surface friction coefficient adjusted to 0.2 to 0.3, and the temperature adjusted to 110 ° C.

  When the upper and lower rolls are nipped, the upper and lower rolls come into contact with each other at the stepped portion, and the narrow portion is not in contact and a gap is formed. Therefore, the substrate material 1 can be preheated without being pressurized.

  In general, a roll in which a heat-resistant rubber is wound around an iron core is used. Examples of the material of the heat resistant rubber include heat resistant silicon rubber and fluoro rubber.

  Heat resistant silicon rubber is difficult to reduce the surface roughness by machining and has large surface irregularities. And since it is soft, if it suppresses with a surface, a convex part will be crushed, a contact area will spread and a frictional force will become strong.

  On the other hand, fluororubber has the characteristic that the friction coefficient can be easily adjusted because the surface roughness can be reduced by machining.

  Next, 103a and 103b are a second set of rolls made of fluororubber and having the same outer diameter of 99.7 mm as the diameters of the thick portions of the first set of rolls 102a and 102b, the temperature of which is adjusted to 140 ° C. Laminate bonding is performed by heating and pressurizing the PET film 120 continuous with 1.

  Reference numeral 104 denotes an AC servo motor for driving the apparatus connected to the second set of rolls 103a and 103b. Reference numeral 105 denotes rotation of the first set of rolls 102a and 102b and the second set of rolls 103a and 103b. It is a drive belt for synchronizing.

  As the first set of rolls 102a and 102b and the second set of rolls 103a and 103b are synchronized, the outer periphery of the narrow portion of the first set of rolls 102a and 102b is as shown in (Table 1). Since the rolls 103a and 103b are smaller by 2.19 mm per roll rotation, the PET film transport amount on the first set of rolls 102a and 102b is reduced.

  That is, since the second set of rolls 103a and 103b rotates by 2.19 mm per rotation more than the first set of rolls, a continuous PET film between the first set of rolls and the second set of rolls 103a and 103b. 120 is extended by 2.19 mm in calculation.

  Since the substrate material 1 is only subjected to the pressure of the second set of rolls 103a and 103b at this position, it is not stretched (aside from thermal expansion) and is attached to the stretched PET film.

  After passing through the second set of rolls 103a and 103b, the continuous PET film 120 in a state of being adhered to the substrate material 1 turns into shrinkage, so that the substrate material 1 also shrinks due to the stress.

  Until now, the amount of stretch of the continuous PET film is considered to have fluctuated depending on the friction coefficient of the first set of rolls. By eliminating the variation of the friction coefficient from time to time, the stretched amount of the PET film was stabilized, and in particular, the dimensional change was remarkably stabilized by eliminating the variation in the friction coefficient at the time of roll replacement (see FIG. 6). Moreover, it was confirmed that the roll was stable after the roll change even when the friction coefficient became 0.15.

  Next, 106a and 106b in FIG. 3 are a third set of rolls having cooling ability. Reference numeral 107 denotes a third set of roll driving motors that are rotated at the same speed or higher than the speed of the second set of rolls.

  No. 108 circulates a refrigerant for efficiently absorbing and discharging heat by the third set of rolls 106a and 106b even when the substrate material 1 is heated and pressurized by the second set of rolls 103a and 103b to reach a high temperature state. It is piping for.

  Air is passed through the refrigerant, but using water is very effective.

  Further, 109a and 109b are used to cool the substrate material 1 and the third set of rolls 106a and 106b by forcibly blowing air immediately after the substrate material 1 is discharged from the third set of rolls 106a and 106b. It is an air nozzle.

  As a result, the B-stage resin contained in the substrate material 1 can be brought to the softening point temperature or less in a short time, so that the dimensional change of the substrate material 1 can be stabilized (see FIG. 7).

  Without the third set of rolls, when the substrate material is glass epoxy, not only the dimensions become unstable, but also waviness and warpage are caused, which causes the yield to deteriorate. The third set of rolls has the ability to form while cooling.

  Reference numeral 110 denotes a feed roll, which has a role of smoothly feeding the substrate material with the PET film pasted backward, and 111 is a dancer roll, which has a function of generating tension for adjusting the dimensional change of the substrate material. And a buffer function for adjusting the feeding of the PET film.

  Reference numeral 112 denotes a feed roll, which has a function of smoothly feeding the substrate material on which the PET film is pasted backward.

  113a and 113b are cutting position adjusting rolls that detect the tip of the substrate with a sensor (not shown) in order to form a single wafer in a state where the substrate material sandwiched between continuous PET films is laminated, It is a roll that controls the dancer roll 111 to stop the substrate material and adjust the cutting position.

  Reference numeral 114 denotes a cutting blade that cuts the substrate material positioned by the cutting position adjusting rolls 113a and 113b into pieces. Reference numeral 115 denotes a laminated substrate material cut into sheets, and is stacked on a stocker 117 (not shown) by a take-out machine.

  By using such a construction method and equipment, highly accurate and stable film lamination is performed.

  Through the above steps, the substrate material 1 and the PET films 4a and 4b are bonded under stable conditions as shown in FIG.

  Next, as shown in FIG.1 (c), the through-hole 10 is formed by irradiating the laser beam 9 on the board | substrate material 1 which affixed PET film.

  After the through holes are formed, the substrate material surface and the inside of the through holes are cleaned to clean them (not shown).

  Next, as shown in FIG. 1 (d), the conductive paste 13 is filled into the through hole 10 with the rubber squeegee 11 using printing or the like. Reference numeral 14 denotes a through hole filled with a conductive paste.

  Next, as shown in FIG. 1 (e), after peeling off the PET film, which is the mask film after filling, the substrate material 1 is heated and dried at 60 ° C. for 30 minutes, so that the substrate material 1 releases the shrinkage stress received during film lamination, and the original dimensions Return to.

  FIG. 5 shows the dimensional behavior of the substrate material in each process. If the amount of shrinkage at the time of lamination varies, the amount of elongation (return) after peeling and drying also varies, but the amount of shrinkage (return amount) is stable because the amount of shrinkage is stabilized by the effect of the present invention.

  Next, as shown in FIG. 1 (f), the substrate material 1 is sandwiched between the metal foils 15a and 15b, and heated and pressed using a hot press apparatus (not shown) to form the substrate material 1 and at the same time have conductivity. The metal foil 15a and the metal foil 15b are electrically connected by the through hole 14 filled with the paste.

  Next, the double-sided circuit forming substrate having the circuit pattern 16 as shown in FIG. 1G is obtained by patterning the metal foils 15a and 15b into a desired shape.

  Next, FIG. 2 shows a schematic diagram of the manufacturing process of the multilayer circuit forming substrate.

  FIG. 2A shows paste-filled substrate materials 202a and 202b from which the double-sided circuit forming substrate 201 and the PET film shown in FIG. After each drying, as shown in FIG. 2 (b), the double-sided circuit forming substrate 201 is used as a core, and the upper and lower substrate materials 202a and 202b are positioned and laminated by a method such as pin lamination, and further sandwiched between metal foils 203a and 203b. To do.

  Next, by performing hot pressing, a four-layer plate shown in FIG. 2C is formed, and conduction of all layers is realized by a through hole filled with a conductive paste provided on the substrate material.

  Next, by patterning the metal foils 203a and 203b into a desired shape, a four-layer circuit forming substrate is obtained as shown in FIG.

  Furthermore, it goes without saying that a further multilayer circuit-formed substrate can be obtained by repeating a plurality of times using the four-layer circuit-formed substrate obtained in this step as a core.

  If the dimensions of the substrate material are stable when stacking and positioning are performed, the accuracy at the time of stacking is also stabilized, so that a highly accurate substrate can be produced.

  As described above, the circuit-forming board manufacturing apparatus and the manufacturing method using the same according to the present invention can eliminate the variation in the dimensional change of the base material and provide a high-density circuit-forming board on which electronic components are mounted. .

Sectional drawing of the process of the manufacturing method of the circuit formation board in embodiment of this invention Sectional drawing of the process of the manufacturing method of the circuit formation board in embodiment of this invention 1 is a schematic configuration diagram of an apparatus for manufacturing a circuit board according to an embodiment of the present invention. The schematic block diagram of the 1st set roll of the manufacturing apparatus of the circuit formation board in embodiment of this invention The figure which shows the dimensional change of the board | substrate material in embodiment of this invention. The figure which shows the dimensional change of the board | substrate material in embodiment of this invention. The figure which shows the dimensional change of the substrate material temperature and substrate material in embodiment of this invention Schematic showing how to measure the coefficient of friction Schematic configuration diagram of a conventional circuit forming board manufacturing apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate material 3a, 3b Laminate roll 4a, 4b PET film 9 Laser beam 10 Through hole 11 Squeegee 13 Conductive paste 14 Through hole 15a, 15b Metal foil 16 Circuit pattern 101a, 101b PET film roll 102a , 102b First set of rolls 103a, 103b Second set of rolls 104 Motor 105 Drive belt 106a, 106b Third set of rolls 107 Motor 108 Refrigerant piping 109a, 109b Cooling air nozzle 110 Feed roll 111 Dancer roll 112 Feed roll 113a , 113b Cutting position adjusting roll 114 Cutting blade 115 Laminated substrate material 201 Core substrate 202a, 202b Paste filled substrate material 203a, 203b Metal foil

Claims (6)

It is composed of a plurality of sets of rolls to which a film is attached by passing between two rolls having a sheet-like work piece in the upper and lower two sets,
A second set of rolls at least behind the first set of rolls;
The first set of rolls is a stepped structure including an end portion and a portion through which a sheet-like workpiece passes,
The diameter of the end of the first set of rolls is larger than the diameter of the portion through which the sheet-like workpiece passes, and is the same as the diameter of the second set of rolls;
The outer periphery of the second set of rolls is larger than the outer periphery of the portion through which the sheet-like workpiece of the first set of rolls passes,
The material of the first set of rolls is heat resistant fluororubber,
The manufacturing apparatus according to claim 1, wherein a surface friction coefficient of the first set of rolls is 0.15 to 1.0. The manufacturing apparatus of Claim 1 provided with the 3rd set roll provided with the cooling means behind the 2nd set roll. The difference between the diameter of the end of the first set of rolls and the diameter of the part through which the sheet-like workpiece passes is larger than the sum of the thickness of the sheet-like workpiece and the thickness of the film to be attached. 2. The apparatus for producing a circuit forming substrate according to 1. As means for rotating the first set of rolls and the second set of rolls in synchronization, a motor is connected to the first set or the second set of rolls to provide rotational driving, and the first set and the second set of rolls. The manufacturing apparatus according to claim 1, wherein the power is transmitted through a belt or a gear. 4. The manufacturing apparatus according to claim 3, further comprising means for applying a cooling gas to the sheet-like workpiece immediately after the third set of rolls. The film continuously supplied to the second set of rolls through the surface of the portion through which the sheet-like workpiece of the first set of rolls of the manufacturing apparatus according to claim 1 passes on both sides of the sheet-like substrate material. Pasting process,
Forming a through hole in the substrate material to which the film is attached;
Filling the through hole with a conductive paste;
Peeling the film from the substrate material;
Sandwiching the substrate material with a metal foil, heating and pressing it,
Forming a circuit of the metal foil,
The process of attaching a film to both sides of the substrate material is as follows:
The operation of preheating the substrate material and the film-like material without pressurizing or adhering them, and the operation of attaching the substrate material to the substrate material by heating and pressurizing the film-like material without stretching the substrate material and by a certain amount. A process for producing a circuit-formed substrate, characterized in that

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