JP2006088260A - Method of perforating flexible resin substrate with adhesive layer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of continuously perforating or cutting a flexible resin substrate having an adhesive layer attached thereto, which is free from a fear of defective cutting at the adhesive layer, and eliminates burrs and deposition of burr waste at a cut surface. <P>SOLUTION: According to the method when the flexible resin substrate having the adhesive layer (4) attached thereto is continuously perforated by using a press machine consisting of a punch (1) and a die (2), a distance (D) from a cutting completion point of the resin substrate by the punch (1) to a lower dead point (A) of the punch (1) in a through hole formed in the die (2), is set in the range of 0.5 mm to 1.0 mm. Further after performing a predetermined number of times of punching, it is preferred that the distance (D) from the cutting completion point to the lower dead point of the punch is extended, and therefore a cut residue remaining in the through hole in the die (2) can be removed by the punch (1). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for punching a flexible resin substrate that is used to obtain a semiconductor package having a metal reinforcing plate bonded thereto and provided with an adhesive layer.

  In order to reduce the size and thickness of electronic devices such as semiconductor devices or various electronic devices to which they are assembled, flexible substrates and TAB (Tape Automated Bonding) mounted thin packages are used as semiconductor packages. As a base material of the semiconductor package, for example, a flexible resin substrate made of polyimide or the like in a desired shape such as a tape is used. However, the flexible resin substrate has a problem that a semiconductor chip or other electronic components cannot be mounted on the flexible resin substrate with good flatness.

  Also, with the recent increase in pin count and density, the mounting of semiconductor packages on circuit boards is more representative of BGA (Ball Grid Array) than the conventional lead-type mounting represented by QFP (Quad Flat Package). Accordingly, the above-described flexible resin substrate has been widely used as a base material for BGA.

  In the case of grid terminal arrangement type mounting, a circuit board such as a mother board and a semiconductor package are contacted by solder balls arranged in a grid pattern. For this reason, the BGA semiconductor package is required to have better flatness than the conventional QFP semiconductor package or the like. A BGA semiconductor package using a flexible resin substrate is generally called T-BGA (Tape-BGA).

  As described above, when an electronic component is mounted on a flexible resin substrate, a metal reinforcing plate or the like is joined to the flexible resin substrate in order to provide good flatness. This bonding is usually performed by applying an adhesive layer. As the adhesive, the types and purposes required of semiconductor packages from acrylic pressure-sensitive types, epoxy-based thermosetting types, polyimide-based thermoplastic types, etc. Is selected as appropriate.

  Below, the outline | summary of an example of the manufacturing method of the wiring board for T-BGA is shown.

(1) A polyimide tape is used as a resin substrate, and an adhesive is laminated on one side of the polyimide tape in layers.

(2) A copper foil is laminated on the obtained adhesive layer.

(3) A resist layer is provided on the surface of the copper foil, patterning is performed using a mask having a desired pattern, an etching mask is created, the exposed portion of the copper foil is dissolved and removed, and the remaining resist layer is removed. Then, a wiring part is formed.

(4) A desired resist portion of the obtained wiring portion is plated, and then a solder resist layer is provided.

(5) Adhesive is provided in layers on the surface of the polyimide tape opposite to the wiring portion, and the obtained adhesive layer is joined while applying pressure and temperature with a roll laminator or the like.

(6) A device hole for housing the semiconductor chip and a hole necessary for the peripheral portion of the pattern are opened using a press machine including a punch and a die.

(7) A T-BGA wiring board is completed by cutting into a predetermined size and attaching a metal reinforcing plate or the like of a predetermined size to the adhesive layer obtained in (5). Alternatively, after providing a device hole or the like, a metal reinforcing plate or the like is bonded to the adhesive layer obtained in (5) above, and then cut into a predetermined size to complete a T-BGA wiring board. Let

  In addition, as another manufacturing method of the wiring board for T-BGA, an adhesive layer is provided on the surface of the metal reinforcing plate instead of the above (5) to (7), and the above (1) to (4) The obtained wiring part may be joined to a resin substrate that has been formed.

  As described in (5) above, pressure and temperature are applied to the adhesive layer provided for bonding the resin substrate and the metal reinforcing plate by roll lamination or the like, and the semiconductor chip is stored as in (6) above. Device holes to be used and holes required in the periphery of the pattern are formed by pressing or cut into a predetermined size. At this time, the adhesive layer is extremely soft compared to a resin substrate such as a polyimide film, so that the adhesive layer is liable to be cut poorly, and burrs are generated on the cut surface of the resin substrate. There is a problem that deposits such as burrs are generated on the surface.

  As a countermeasure against such a problem, for example, Japanese Patent Application Laid-Open No. 2000-6096 discloses an apparatus for removing the adhering matter by suction, but it is difficult to remove burrs including an adhesive and the like. However, there was a problem that operation and maintenance were expensive.

JP 2000-6096 A

  The present invention provides a method in which, when continuously drilling or cutting a flexible resin substrate provided with an adhesive layer, the adhesive layer does not have cutting defects and does not generate deposits such as burrs. The purpose is to do.

  The method of the present invention is a method of continuously drilling a flexible resin substrate provided with an adhesive layer using a press machine comprising a punch and a die, and the cutting completion point of the resin substrate by the punch The distance from the bottom dead center of the punch in the insertion hole of the die to 0.5 mm to 1.0 mm.

  Furthermore, it is desirable to remove the cut material remaining in the insertion hole of the die with the punch by increasing the distance from the cutting completion point to the bottom dead center of the punch after a predetermined number of punches.

  According to the present invention, when the flexible resin substrate provided with the adhesive layer is continuously drilled or cut, the adhesive layer does not have a cutting failure, and the cut surface of the resin substrate has a burr. , Or burrs can be prevented from adhering.

  Burr due to defective cutting basically occurs due to the state of the cutting edge of the mold and the clearance between the die and the punch. In other words, if a proper clearance can be secured, or if the state of the cutting edge can be properly maintained by regrinding or the like, it is possible to maintain a good state with no problems.

  However, according to the observation of the present inventor, the adhesive scraped by the side surface of the punch when the punch is lowered adheres to the side surface of the punch, and the surface to be cut when the punch is lifted up. It was found that it occurs by reattaching to the surface. Accordingly, it has been found that the time and distance at which the punch contacts the adhesive may be shortened in order to prevent the sticking of burrs, and the present invention has been completed.

  In the method of the present invention, when a punching and die press machine is used to continuously drill a hole in a flexible resin substrate provided with an adhesive layer, the cutting completion point of the resin substrate by the punch is determined. The distance from the bottom dead center of the punch in the insertion hole of the die to 0.5 mm to 1.0 mm. If it is shorter than 0.5 mm, the cutting is often incomplete and unsuitable. On the other hand, when the length is longer than 1.0 mm, the occurrence of burr dust adhesion becomes significant.

  In the implementation of the method of the present invention, so-called clogging is likely to occur in which the cut material remains in the insertion hole of the die. Therefore, in order to prevent clogging of the discharge port of the punched portion due to the scrap, after a predetermined number of punches, the punch is inserted deeper than the above setting, and the cut material remaining in the through hole of the die is removed. The number of times the predetermined punching is performed is also affected by the properties of the adhesive to be punched, and is set as appropriate after checking in advance.

  On the other hand, when the cut product is a semiconductor package, any conventional collecting means may be employed as appropriate.

Example 1
A general T-BGA material was prepared as follows, and a hole having a diameter of 0.5 mm was continuously formed. FIG. 1 is a cross-sectional view showing a state in which a punching process is performed on a flexible resin substrate provided with an adhesive layer.

  A 75 μm thick polyimide film (Ube Industries, Upilex S) (3), a 38 μm thick PET film (5) and a 50 μm thick adhesive (4) (Toray Industries, Inc. TSA61) was laminated.

  Next, using a 3 μm clearance mold consisting of a punch (1) and a die (2), immediately after regrind, the distance (D) from the cutting completion point to the bottom dead center is set to 0.5 mm, and 100 pcs continuous. In the processing, punching was performed for 8 hours.

  There was no uncut piece from the start to the end of processing, and no burr was attached to the cut surface of the resin substrate.

(Example 2)
Punching was performed in the same manner as in Example 1 except that the distance (D) from the cutting completion point to the bottom dead center was 1.0 mm. There was no uncut piece from the start to the end of processing, and no burr was attached to the cut surface of the resin substrate.

(Comparative Example 1)
Punching was performed in the same manner as in Example 1 except that the distance (D) from the cutting completion point to the bottom dead center was 0.4 mm. About 20% of uncut pieces were seen from the start to the end of processing.

(Comparative Example 2)
Punching was performed in the same manner as in Example 1 except that the distance (D) from the cutting completion point to the bottom dead center was 1.1 mm. From the start to the end of processing, the adhesion of burrs to the cut surface of the resin substrate was remarkable.

It is sectional drawing which shows a mode that a punching process is carried out to the flexible resin substrate to which the adhesive bond layer was provided.

Explanation of symbols

1 Punch 2 Die 3 Resin substrate 4 Adhesive layer 5 Cover film A Bottom dead center B Top dead center D Distance from cutting completion point to bottom dead center

Claims (2)

  In a method of continuously drilling a flexible resin substrate provided with an adhesive layer by using a press consisting of a punch and a die, the insertion hole of the die is used from the point of completion of cutting the resin substrate by the punch. The distance from the bottom dead center of the punch is set to 0.5 mm to 1.0 mm.   2. The method according to claim 1, wherein after a predetermined number of times of punching, the cut material remaining in the insertion hole of the die is removed by the punch by increasing the distance from the cutting completion point to the bottom dead center of the punch. .

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