Patent Application
20060076104
1. Field of the Invention
The present invention relates to a film peeling apparatus for peeling a carrier film from a board to which an insulating material and associated carrier film has been bonded, and a method of manufacturing a wiring board which includes a step of peeling a carrier film from a board to which an insulating material and associated carrier film has been bonded.
2. Description of the Related Art
Conventionally, a process of manufacturing a build-up multi-layer wiring board includes a step of bonding an insulating material to a surface of a board. Examples thereof include laminating a photosensitive resist film on the surface of the board and laminating an inter-layer film formed of a photosensitive or thermosetting insulating material on the surface of the board. In general, the outer surface of the insulating material is covered with a carrier film made of PET (polyethylene terephthalate). Accordingly, in order to begin processing of the bonded insulating material, the carrier film must be peeled from the surface of the insulating material in advance.
Proposed methods for pealing off such a carrier film include a method of contacting a tacky member such as a tacky roller with a carrier film and peeling off the carrier film in this state, and a method of jetting air against a clearance between a carrier film and an insulating material and pulling off the carrier film by means of force of the air.
In another proposed method for pealing off a carrier film, a portion (pealing initiation portion) where the carrier film is lifted from an insulating material is formed in a peripheral portion of the carrier film, and the carrier film is peeled off from the pealing initiation portion. In one proposed method of forming such a pealing initiation portion, a knurling roll is moved along the surface direction of a carrier film, while being rotated, so as to damage the carrier film and thereby form a pealing initiation portion (see, for example, Patent Document 1). In another proposed method of forming such a pealing initiation portion, a film pressing member is moved along the surface direction of a carrier film so as to lift the carrier film and thereby form a pealing initiation portion (see, for example, Patent Document 2).
[Patent Document 1] Japanese Patent Application Laid-Open (kokai) No. 2000-86080 (FIG. 1, etc.)
[Patent Document 2] Japanese Patent Application Laid-Open (kokai) No. H10-324454 (FIG. 2, etc.)
3. Problems to be Solved by the Invention
However, in the case where a tacky member or air is used (i.e., the case in which a pealing initiation portion is not formed), a carrier film is peeled off in a state in which the entire carrier film closely adheres to the insulating material. In this case, because the carrier film must be peeled off against the adhesion force acting between the carrier film and the insulating material, success in peeling off the carrier film is low.
Meanwhile, in the case where a knurling roll or a film pressing member is moved along the surface direction of a carrier film, the carrier film is peeled off from a pealing initiation portion. At the pealing initiation portion, no adhesion force acts between the carrier film and the insulating material, and therefore, the carrier film is more likely to be peeled off as compared with the case where a pealing initiation portion is not formed. However, if an excessively large force acts on the carrier film when the knurling roll or the film pressing member is moved, the carrier film may be torn to a considerable extent from that portion. As a result, a portion of the carrier film remains on the insulating material without being peeled off.
In addition, if the force acting on the carrier film is excessively strong, the possibility of the insulating material and/or the board being damaged becomes high, resulting in a decrease in yield. Moreover, the insulating material is formed of a fragile material which collapses when it is damaged only slightly. Therefore, the possibility of a portion of the insulating material collapsing to generate debris is high. In addition, if such debris adheres to the insulating material, the thickness of the insulating material becomes non-uniform, which is a cause of reduced yield.
The present invention has been accomplished in view of the above problems of the prior art, and an object of the invention is to provide a film peeling apparatus and a method of manufacturing a wiring board, which apparatus and method can peel off a carrier film at a high success rate while maintaining high yield.
The above objects of the present invention have been achieved by providing a film peeling apparatus for peeling a carrier film from a board to which an insulating material and carrier film has been bonded, the carrier film being arranged on a side of the insulating material opposite the board, the apparatus comprising a board support section for supporting the board; a hole forming jig having a tip-sharpened member for piercing a peripheral portion of the carrier film so as to form a through hole; jig drive means for driving the hole forming jig so as to pierce the carrier film by means of the tip-sharpened member; and a peeling mechanism for peeling off the carrier film, starting from an air pocket formed around the through hole. Notably, a needle or the like is preferably used as the tip-sharpened member.
Accordingly, in the film peeling apparatus, before the carrier film is peeled off, the hole forming jig is driven so as to pierce the carrier film by use of the tip-sharpened member such as a needle to form a through hole. An air pocket can be formed around the through hole upon removal of the tip-sharpened member from the carrier film. Since no adhesive force acts between the insulating material and the portion of the carrier film where the air pocket is formed, the film peeling mechanism can readily peel off the carrier film, starting from the air pocket. Therefore, the carrier film can be peeled off at a higher success rate than in the case where a through hole is not formed.
In addition, the through hole is not formed by moving the tip-sharpened member, such as a needle, along the surface direction of the carrier film, but rather by driving the hole forming jig so as to pierce the carrier film by means of the tip-sharpened member. Therefore, an area in which the insulating material or the board is damaged by the tip-sharpened member, such as a needle, can be reduced, and lowering of yield can be suppressed. In addition, because the degree of damage to the insulating material decreases, generation of debris due to adulteration of a portion of the insulating material can be suppressed. Therefore, it is possible to suppress lowering of yield caused by the adverse effects of such debris on the insulating material.
The tip-sharpened member refers to a member whose tip has a sharpened shape. Specific examples thereof include a needle and a cutting tool or cutlery such as a knife. That is, the member may assume a bar-like shape or a plate-like shape as a whole, so long as its tip end has a sharp shape. A member having a sharpened tip can concentrate pressure at the tip end to a greater extent as compared with a member which does not have a sharpened tip, and can simply form a through hole with relatively small force. Notably, the most preferable tip-sharpened member is a needle, which can further reduce the area over which the insulating material and the board are damaged.
Example materials which are preferably used to form the carrier film include paper and resin having flexibility. Among these, a material is preferably selected which does not damage the insulating material, is inexpensive, and is strong even when formed into a thin shape. Notably, resin and paper are preferred, from the viewpoint of easiness of reuse. Specific examples of the resin material for use as the carrier film include PET resin (polyethylene terephthalate resin), EP resin (epoxy resin), and PI resin (polyimide resin).
The insulating material and associated carrier film can be formed, for example, by a method of applying a liquid insulating material to the carrier film. A method of laminating a film-shaped insulating material onto a carrier film may also be employed.
Generally, the board is formed of a resin material or a ceramic material. Examples of the board mainly formed of a resin material include an EP resin (epoxy resin) board, a PI resin (polyimide resin) board, a BT (bismaleimide triazine resin) board, and a PPE (polyphenylene ether) board. Alternatively, a board formed of a composite material including one of these resins and glass fiber (glass woven fabric or glass nonwoven fabric) or organic fiber such as polyamide fiber may be used. Alternatively, a board formed of a resin-resin composite material which is formed of a fluorine-based resin matrix having a three-dimensional network structure, such as open-cell PTEE, which is impregnated with a thermosetting resin such as epoxy resin, may be used. Examples of the board mainly formed of a ceramic material include a board formed of alumina, aluminum nitride, boron nitride, silicon carbide, silicon nitride, or other suitable ceramic material.
The board preferably forms a wiring board which has an insulating layer formed from the insulating material and associated carrier film, and semiconductor devices and other electronic components are mounted on such a wiring board.
Preferably, the board support section includes a stop for holding the board in a set position when the jig drive means drives the hole forming jig. By virtue of this structure, a shift in the position of the board can be prevented. Thus, the through hole can be formed at a precise position by piercing the carrier film using a tip-sharpened member such as a needle. Further, the position of the board does not shift in a state where the tip-sharpened member such as a needle has reached the insulating material. Thus, the insulating material is not scratched by the tip-sharpened member and is hardly damaged.
Examples of the stop include a stop which comes into contact with the upper surface or lower surface of the board so as to position the board, and a stop which comes into contact with a leading edge of the board. However, a stop which comes into contact with a leading edge of the board is preferred. In this case, since the stop restricts movement of the board along the surface direction, the board is easily positioned. Further, such stop does not damage the insulating material or the board when positioning the board.
Preferably, the board support section includes a deflection prevention means, operable when a portion of the board deflects downward under the force of gravity, for supporting a portion of the board from the lower side thereof. By virtue of this configuration, the jig drive means can pierce the carrier film by means of the tip-sharpened member such as a needle in a state in which the deflection of the board has been corrected, so that the through hole can be formed at a desired position with greater precision.
A plurality of through holes penetrating the carrier film may be formed in a peripheral portion of the carrier film. The plurality of through holes are preferably formed so as to extend in the thickness direction of the carrier film (Z-axis direction).
The shape of the through hole can be freely determined and is defined by the shape of the tip-sharpened member, such as a needle, in consideration of the material, thickness, etc., of the carrier film. No particular limitation is imposed on the diameter of the through hole. However, the diameter of the through hole is preferably not less than 0.1 mm but not greater than 1.5 mm, more preferably not less than 0.5 mm but not greater than 1.0 mm. When the diameter of the through hole is less than 0.1 mm, only a small air pocket is formed. As such, the operation of peeling the carrier film, which starts from the air pocket, may not be able to proceed. When the diameter of the through hole is greater than 1.5 mm, a crack may be generated from the edge of the through hole when forming the through hole.
Preferably, the plurality of through holes are arranged in a line along the edge of the leading end of the carrier film, wherein the row of the through holes extends perpendicular to the advancement direction of the board. If a plurality of rows of the through holes extend perpendicular to the advancement direction of the board, the area in which the insulating material and the board are damaged by the tip-sharpened member, such as a needle, increases, so that a portion of the insulating material which is necessary for constructing a wiring board may be damaged by the tip-sharpened member, such as a needle.
Notably, the distance between the centers of adjacent through holes is preferably not less than 1.0 mm but not greater than 10 mm, more preferably not less than 2.5 mm but not greater than 7.5 mm. When the inter-center distance is less than 2.5 mm, only the portions where air pockets are present are peeled off, with increasing possibility that the remaining portion of the carrier film is not peeled off and is left on the insulating material. When the inter-center distance is greater than 7.5 mm, applying an adhesive tape to the entirety of a portion where the air pockets are formed becomes difficult, for example, in the case where the adhesive tape is applied to the portion where the air pockets are formed, and is lifted so as to peel off the carrier film.
A needle, which is a typical example of the tip-sharpened member, is not required to have very high dimensional accuracy. This is because the needle is used to form a through hole to thereby form an air pocket necessary for peeling the carrier film. The cross sectional shape of the needle may be generally circular, generally rectangular, or generally triangular. However, the needle preferably has a generally circular cross section as in the case of an ordinary needle. In this case, the outer circumferential surface of the needle is less likely to be caught by the insulating material, so that the fragile insulating material is unlikely to be damaged by the needle.
The material used for the needle is freely determined in consideration of cost, mechanical strength, etc.; however, a metallic material is preferably used. Examples of the metallic material include high-speed tool steel (SKH steel; hardness HRC 61 to 64) such as SKH51, carbon tool steel (SK steel) such as SK3 and SK5, rolled steel for general structure (SS steel) such as SS400, and carbon steel for machine structural use (SC steel) such as S50C and S55C.
No particular limitation is imposed on the diameter of the needle. However, the diameter of the needle is preferably not less than 0.1 mm but not greater than 1.5 mm, more preferably, not less than 0.5 mm but not greater than 1.0 mm. When the diameter is less than 0.1 mm, the needle is easily broken. When the diameter is greater than 1.5 mm, a crack may be formed in the carrier film when a through hole is formed. The distance between the centers of adjacent needles is preferably not less than 1.0 mm but not greater than 10 mm, more preferably, not less than 2.5 mm but not greater than 7.5 mm. When the inter-center distance is less than 2.5 mm, only the portions where air pockets are present are peeled off. Consequently, the possibility that the remaining portion of the carrier film is not peeled off and is left on the insulating material increases. When the inter-center distance is greater than 7.5 mm, applying an adhesive tape to the entirety of a portion where the air pockets are formed becomes difficult in the case where the adhesive tape is applied to the portion where the air pockets are formed, and is lifted so as to peel off the carrier film.
The projection amount of the needle (specifically, the projection amount of the needle, as measured from a surface of the needle support member from which the needle projects) is preferably set to an amount not less than 5 mm but not greater than 50 mm, particularly preferably not less than 5 mm but not greater than 30 mm. When the projection amount is less than 5 mm, the needle support member may come into contact with the carrier film when the needle pierces the carrier film. When the projection amount is greater than 50 mm, the needle may break when the needle pierces the carrier film.
The piercing depth of the tip-sharpened member, such as a needle, is preferably set such that the tip of the tip-sharpened member passes through the carrier film and reaches the insulating material but does not reach the board. By virtue of this setting, the air pocket is reliably formed as a result of the tip-sharpened member, such as a needle, penetrating the carrier film. In addition, since the piercing depth of the tip-sharpened member, such as a needle, is set such that the tip of the tip-sharpened member does not reach the board, the tip-sharpened member, such as a needle, does not damage the board.
When the tip-sharpened member, such as a needle, is removed, frictional force is produced between the outer circumferential surface of the tip-sharpened member and the carrier film, and the frictional force acts in a direction for lifting the carrier film. Furthermore, in the present invention, since the piercing depth of the tip-sharpened member, such as a needle, is set such that the tip of the tip-sharpened member passes through the carrier film and reaches the insulating material, the frictional force acts on the carrier film over a longer period of time as compared with the case where the tip of the tip-sharpened member merely passes through the carrier film. Therefore, the carrier film is more likely to be lifted, and a larger air pocket can be formed.
Preferably, the hole forming jig includes a support member which removably supports a plurality of tip-sharpened members, and an elastic body disposed at the base end portions of the plurality of tip-sharpened members. In particular, when the tip-sharpened members are needles, preferably, the hole forming jig includes a needle support member which removably supports a plurality of needles, and an elastic body disposed at the base end portions of the plurality of needles. By virtue of this configuration, when the needles have worn out, the needles can be removed through a simple operation of separating the needles from the needle support member. Therefore, the needle exchange operation becomes easier. Further, in the case where the needle support member capable of supporting a plurality of needles is used, even when one or a few needles fail to from through holes, the carrier film can be peeled off if the remaining needles succeed in forming the through holes. Therefore, the carrier film can be peeled off at a higher success rate. In addition, in the case where the projection amounts of the respective needles differ from one another, the differences in projection amount are absorbed through deformation of the elastic body when the needles come into contact with the carrier film. Accordingly, the plurality of needles can be brought into contact with the carrier film with uniform force.
When the jig drive means performs the operation of piercing the carrier film by use of the tip-sharpened member, such as a needle, the jig drive means may advance the tip-sharpened member perpendicular to the surface direction of the carrier film or may advance the tip-sharpened member in a direction inclined with respect to the surface direction of the carrier film. However, advancing the tip-sharpened member perpendicular to the surface direction of the carrier film is preferred. In this case, the tip-sharpened member, such as a needle, does not move along the surface direction of the carrier film, and therefore, the insulating material is not scratched by the tip-sharpened member. Therefore, the area over which the insulating material or the board is damaged by the tip-sharpened member, such as a needle, can be further reduced.
In particular, in the case where the tip-sharpened member is a needle, the jig drive means preferably performs the operation of piercing the carrier film by means of the needle by axially advancing the needle, and performs the operation of removing the needle from the carrier film by axially retreating the needle. In this case, the direction along which the needle is advanced to pierce the carrier film coincides with the direction along which the needle is removed from the carrier film. Therefore, the needle is unlikely to be caught by the insulating material, and damage to the insulating material can be prevented more effectively.
Another means for solving the above-described problems is a method of manufacturing a wiring board having an insulating layer, which comprises an application step of applying an insulating material and carrier film to a board, the carrier film being arranged on a side of the insulating material opposite the board; a through-hole forming step, performed after the application step, of piercing a peripheral portion of the carrier film by use of a tip-sharpened member to thereby form a through hole; and a peeling step, performed after the through-hole forming step, of peeling off the carrier film, starting from an air pocket formed around the through hole to leave the insulating material, which serves as the insulating layer, on the board. Notably, the wiring board may be a build-up multi-layer wiring board having a build-up layer composed of alternately layered inter-layer insulating layers and conductor layers, and the insulating material and associated carrier film may be used to form the inter-layer insulating layers. Notably, preferably a needle or the like is used as the tip-sharpened member.
A method of manufacturing a wiring board will now be described.
First, the application step is performed so as to apply an insulating material and associated carrier film to a board. Notably, the insulating material and associated carrier film is preferably applied to cover the entire surface of the board except for a peripheral region thereof.
After completing the application step, the board, to which the insulating material and associated carrier film has been applied, is conveyed, and then the through-hole forming step is performed. Specifically, the hole forming jig is driven so as to axially advance the tip-sharpened member, such as a needle, from the retreat position to the use position, to thereby pierce a peripheral portion of the carrier film by means of the tip-sharpened member. As a result, a through hole is formed in the peripheral portion of the carrier film. After that, when the tip-sharpened member moves to the retreat position, an air pocket is formed around the through hole, and the tip-sharpened member separates from the peripheral portion of the carrier film.
After completing the through-hole forming step, the peeling step is performed. Specifically, the carrier film is peeled off, starting from the air pocket formed around the through hole, whereby the insulating material, which serves as an insulating layer, remains on the board. Preferably, an adhesive tape application step of applying an adhesive tape to a portion of the carrier film where the air pocket is present is carried out between the application step and the peeling step; and in the peeling step, the carrier film is peeled off by lifting the adhesive tape. In the present invention, the adhesive tape application step is performed after the through-hole forming step, and the peeling step is performed after the adhesive tape application step. In this case, the carrier film can be easily peeled off by grasping and pulling the adhesive tape. Further, since heat need not be applied to the carrier film in the peeling step, degradation of the insulating material (e.g., thermal hardening) can be prevented. Moreover, the adhesive tape is preferably taken up by a film take-up means for taking up the carrier film. As a result, the carrier film is completely peeled off, and the insulating material, which serves as an insulating layer of the wiring board, remains on the board. Further, when the adhesive tape is taken up in the form of a roll, the volume of waste can be reduced.
The adhesive tape application step may be performed before the through-hole forming step. That is, the above-mentioned method may be modified such that the adhesive tape application step is performed after the application step; after the adhesive tape application step, the through-hole forming step is performed so as to pierce, by means of a needle, the portion to which the adhesive tape has been applied to thereby form a through hole; and the peeling step is performed after the through-hole forming step.
According to these manufacturing methods, the carrier film can be peeled off at a high success rate. Accordingly, the above-described wiring board can be manufactured efficiently.
Reference numerals used to identify various structural features in the drawings include the following.
An embodiment of the present invention in the form of a film peeling apparatus for wiring board manufacture will be described with reference to FIGS. 1 to 8. However, the present invention should not be construed as being limited thereto.
As shown in
A pair of stopper moving mechanisms 43 are disposed between the two support columns 46 on the support base 45. In the present embodiment, each of the stopper moving mechanisms 43 includes an air cylinder having a vertically movable rod portion 47. A frame 48 having a generally squarish-C-shaped cross section (see
As shown in
Further, the film piercing mechanism 2 has a pair of the punch units 21. The punch units 21 are fixed to an upper-side support beam 22 such that they are located above the corresponding stopper moving mechanisms 43. In the present embodiment, each of the punch units 21 includes an air cylinder 23 (jig drive means), and the above-mentioned hole forming jig 51, which can be moved upward and downward by means of the air cylinder 23. The air cylinder 23 drives the hole forming jig 51 so as to pierce the carrier film 12 by use of the needles 57.
As shown in FIGS. 2 to 4, each hole forming jig 51 is a tool for forming the above-described through holes 16 by piercing a peripheral portion of the carrier film 12. Each hole forming jig 51 has a jig main body 53, and a needle support member 54 is removably attached to the jig main body 53 by use of a knob screw 55 for manual fastening. As shown in
Further, the film piercing mechanism 2 includes a board detection sensor (not shown) disposed in the vicinity of a conveyance path of the board 15. The board detection sensor detects when a leading end portion of the conveyed board 15 has reached a predetermined position. Specifically, the board detection sensor detects that the edge portion 13 (see
Notably, the film piercing mechanism 2 includes solenoid valves (not shown). When the edge portion 13 is determined to have reached a position below the needles 57, through control of the solenoid valves, the stopper moving mechanisms 43 are driven, so that the stops 49 abut the leading end of the board 15.
As shown in FIGS. 2 to 4 and 7, the needles 57 move vertically between a use position (see
As shown in
When the adhesive tape 31 is pulled off as a result of being wound around the film pull off roller 33, the leading end of the carrier film 12 is pulled by means of the film pull-off roller 33, so that the air pockets 17 increase in volume. At that time, the air pockets 17, which are formed around the locations where the through holes 16 are formed in the edge portion 13, expand outward; i.e., toward the end of the edge portion 13. As a result, the air pockets 17 expand over the entire width of the edge portion 13, and finally, the edge portion 13 separates from the inter-layer insulating film 14. A portion of the carrier film 12 peeled off by means of the film pull-off roller 33 is taken up by the film take-up roller 34.
Next, a method of manufacturing a build-up multi-layer wiring board by use of the above-described film peeling apparatus 1 will be described.
First, drilling is performed for a copper clad laminate by use of a drilling machine, whereby through holes (not shown) are previously formed in the copper clad laminate at predetermined positions. Notably, through holes may be formed in the copper clad laminate by means of laser drilling performed by use of a YAG laser or a carbon dioxide laser. Subsequently, electroless copper plating and copper electroplating are performed in accordance with a conventionally known method, whereby plated through holes are formed. Further, copper foils on the opposite surfaces of the copper clad laminate are etched; i.e., a first conductor layer is patterned by a subtractive method. Specifically, after electroless copper plating is carried out, copper electroplating is performed, while the resultant electroless copper plating layer is used as a common electrode. Further, a dry film is laminated, and is subjected to exposure and development, whereby the dry film is formed into a predetermined pattern. In this state, unnecessary portions of the copper electroplating layer, the electroless copper plating layer, and the copper foils are removed. After that, the dry film is peeled off, whereby the board 15, which is a double-sided board, is obtained. Notably, the board 15 may be formed by a semi-additive method. Specifically, after electroless copper plating is carried out, exposure and development are performed to form a plating resist of a predetermined pattern. In this state, copper electroplating is performed, while the resultant electroless copper plating layer is used as a common electrode. After that, the resist is dissolved and removed, and unnecessary portions of the electroless copper plating layer are removed by etching. As a result, the board 15, which is a double-sided board, is obtained.
Next, an application step is performed by use of a conventionally known laminator whereby the inter-layer insulating film 14 with the carrier film 12 is laminated on the main face of the board 15.
After the application step, the board 15, to which the inter-layer insulating film 14 and associated carrier film 12 has been applied, is conveyed to the film piercing mechanism 2. At that time, the board 15 abuts stops 49 within the film piercing mechanism 2 and stops. Subsequently, a through-hole forming step is performed. Specifically, the air cylinders 23 are driven so as to axially advance the needles 57 from the retreat position (see
After completing the through-hole forming step, an adhesive tape applying step is performed. Specifically, the stopper moving mechanisms 43 are driven so as to lower the stops 49, and the stops 49 are brought out of abutment with the board 15. The board 15 is then conveyed to the film peeling mechanism 4. Subsequently, the tape applicator is operated to apply the adhesive tape 31 such that the adhesive tape 31 adheres to a portion of the carrier film 12 where the air pockets 17 are formed and a peripheral portion of the carrier film 12 of a different board 15 located forward with respect to the advancement direction (see
Next, a peeling step is performed for peeling off the carrier film 12 from the air pockets 17 formed around the through holes 16 and serving as starting points. Specifically, the adhesive tape 31, which has been applied to a portion where the air pockets 17 are present, is pulled off by means of the film pull-off roller 33, whereby the adhesive tape 31 is lifted, and the carrier film 12 is peeled off. As a result, the inter-layer insulating film 14, which serves as an inter-layer insulating layer of a build-up multi-layer wiring board, remains on the board 15. Notably, the peeled portion of the carrier film 12 is taken up by the film take-up roller 34 for collection. Further, the board 15, from which the carrier film 12 has been peeled, is conveyed outside of the film peeling apparatus 1 by means of the board carry-out mechanism 3.
Subsequently, the inter-layer insulating film 14 of the carried-out board 15 is laser beam drilled, thereby forming an inter-layer insulating layer having blind holes (vias) at positions where via conductors are to be formed (inter-layer insulating layer forming step). Notably, in a case where the inter-layer insulating film 14 is formed of photosensitive epoxy resin, an inter-layer insulating layer having blind holes may be formed by exposing and developing the inter-layer insulating film 14. Next, electroless copper plating is carried out in accordance with a conventionally known method (e.g., a semi-additive method), and exposure and development are performed to form a plating resist having a predetermined pattern. In this state, copper electroplating is performed, while the resultant electroless copper plating layer is used as a common electrode, whereby via conductors are formed in the blind holes, and a copper plating layer is formed on the inter-layer insulating layer. After that, the resist is dissolved and removed, and unnecessary portions of the electroless copper plating layer are removed by etching. As a result, a second conductor layer is formed on the inter-layer insulating layer (conductor layer forming step).
Subsequently, the above-described application step to the conductor layer forming step are repeated, whereby the inter-layer insulating layer and the conductor layer are alternately layered. As a result, a build-up layer is formed, and a desired build-up multi-layer wiring board is completed.
Accordingly, the present embodiment provides the following effects.
(1) In the film peeling apparatus 1 of the present embodiment, before the carrier film 12 is peeled off, the hole forming jigs 51 are driven so as to pierce the carrier film 12 by use of the needles 57, whereby through holes 16 are formed. Thus, portions of the carrier film 12 around the through holes 16 can be lifted so as to form the air pockets 17 (i.e., peeling initiation portion). Since no adhesive force acts between the inter-layer insulating film 14 and the portions of the carrier film 12 where the air pockets 17 are formed, the film peeling mechanism 4 can readily peel off the carrier film 12, starting from the air pockets 17. Therefore, the carrier film 12 can be peeled off at a higher success rate than in the case where the through holes 16 are not formed.
In the case where the through holes 16 are not formed, the possibility of peeling failure where the carrier film 12 cannot be peeled is not less than 40% but not greater than 50%. In contrast, in the case of the present embodiment, when an attempt was made to peel the carrier film 12 from 480 boards 15, the number of the boards 15 from which the carrier film 12 could not be peeled was four. Therefore, the possibility of peeling failure in the present embodiment is about 0.83%, which is very low.
In addition, in the film peeling apparatus 1, the through holes 16 are not formed by moving the needles 57 along the surface direction of the carrier film 12, but by driving the hole forming jigs 51 so as to pierce the carrier film 12 by use of the needles 57. Since the needles 57 are not moved along the surface direction, neither the inter-layer insulating film 14 nor the board 15 is scratched by the needles 57, and an area in which the inter-layer insulating film 14 or the board 15 is damaged can be reduced. Therefore, defective products are hardly produced, and lowering of yield can be suppressed. Since the degree of damage to the inter-layer insulating film 14 decreases, generation of debris stemming from adulteration of a portion of the inter-layer insulating film 14 can be suppressed. Therefore, it is possible to suppress generation of defective products attributable to such debris which adheres to the inter-layer insulating film 14 and makes the thickness of the inter-layer insulating film 14 non-uniform. Thus, lowering of yield can be suppressed.
(2) In the present embodiment, during the piercing operation, the needles 57 move in the thickness direction of the carrier film 12. Therefore, even when a strong force is applied from the needles 57 to the carrier film 12, the areas in which the carrier film 12 is damaged can be minimized (to only the through holes 16). This reduces the possibility of tearing the carrier film 12 from the vicinity of the through holes 16 to a large extent when the carrier film 12 is peeled off. Therefore, the possibility that a portion of the carrier film 12 is not peeled off and left on the inter-layer insulating film 14 can be reduced.
The embodiment of the present invention may be modified as follows.
In the above-described embodiment, the piercing depth of the needles 57 is set such that the tip portions of the needles 57 pass through the carrier film 12 and reach the inter-layer insulating film 14 but do not reach the board 15. However, the piercing depth of the needles 57 may be set such that the tip portions of the needles 57 pass through the carrier film 12 but do not reach the inter-layer insulating film 14.
In the above-described embodiment, the film peeling apparatus 1 is used for forming an inter-layer insulating layer of a build-up multi-layer wiring board. However, the film peeling apparatus 1 may be used for forming an insulating layer of a wiring board other than the build-up multi-layer wiring board.
The film peeling apparatus 1 of the above-described embodiment is used to peel the carrier film 12 from an insulating material (inter-layer insulating film 14), which forms an inter-layer insulating layer of a build-up multi-layer wiring board. However, the film peeling apparatus 1 may be used to peel the carrier film 12 from an insulating material which forms a solder resist or plating resist.
In the film peeling apparatus 1 of the above-described embodiment, the through holes 16 are formed by use of the hole forming jigs 51 having straight needles 57. However, in place of the needles 57 having such a shape, hook-shaped needles may be used.
In the film peeling apparatus 1 of the above-described embodiment, the through holes 16 are formed by use of the hole forming jigs 51 having the needles 57. However, the tip-sharpened member is not limited to the needles 57 and may have any one of the following structures. In another embodiment shown in
Even when the hole forming jigs 51 each equipped with one of the knives 110, 120, 130, and 140 having the above-described structures are used, the through holes 16 can be formed in the carrier film 12 and the air pockets 17 can be formed around the through holes 16.
It should further be apparent to those skilled in the art that various changes involved in detail of the invention as shown and described may be made. It is intended that such changes be included within the spirit and scope of the claims appended hereto.
This application is based on Japanese Patent Application No. 2004-279962, filed Sep. 27, 2004, incorporated herein by reference in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2004-279962 | Sep 2004 | JP | national |
