JP2005175124A - Wiring module and printed circuit board for mounting the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiring module having ease of use and a high degree of freedom, wherein the cost is reduced by decreasing the number of layers of a printed circuit board for an electronic apparatus and high density cross wires are realized, and to provide the printed circuit board for mounting the wiring module. <P>SOLUTION: The wiring module comprises a plurality of pairs, each comprising external connection terminals and wires interconnecting the external connection terminals on an insulation layer. Further, in the wiring module, one part of the external connection terminals is collectively arranged to a prescribed region of the wiring module, and another part of the external connection terminals in pairs, with the one part above, is collectively arranged to the other region. Moreover, in the wiring module, a pair of the external connection terminals and the wires has no electrical connecting part with another pair. Desired wiring is completed for the printed circuit board, by mounting the wiring module onto the printed circuit board, wherein the connection terminals in pairs are provided at positions, straddling at least one or more wires, to connect the connection terminals provided to the printed circuit board to the external connection terminals in the wiring module. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high-density wiring for high-speed signals, a printed wiring board for mounting on a semiconductor device capable of reducing the cost by reducing the number of wiring layers, and a module for complementing the wiring.

In the prior art, when there is a wiring intersection, the number of layers of the printed wiring board is increased, and one wiring is bypassed to another layer. This makes it possible to deal with a case where there are a large number of intersecting wirings, but increasing the number of layers directly increases the cost and may not be applicable depending on the application. On the other hand, when there are few intersecting wirings, a chip type resistor called a jumper chip or a jumper wire is connected. Patent Document 1 is an improvement of a jumper chip that can handle only one intersection with one chip, and is intended to replace a plurality of jumper chips with a multi-pin semiconductor package type ceramic multilayer wiring board. Yes, this is LCC (Leadless Chip)
Carrier) type terminal shape. In Patent Document 2, a plurality of jumper wires are sandwiched and integrated into a film, and end portions of the jumper wires are exposed so that they can be connected.

The known literature is shown below.
Japanese Patent Laid-Open No. 7-50462 Japanese Utility Model Publication No. 5-79971

  When a semiconductor package type ceramic multilayer wiring board is used, the terminal position and size are limited, so it is difficult to use, the terminal pitch is larger than the wiring pitch, and the wiring routing is affected. Ceramic multilayer substrate However, it is expensive. A pitch of 0.5 to 1.27 mm is generally used for terminals of a semiconductor package such as an LCC type. On the other hand, in recent printed wiring boards for electronic devices, where the miniaturization of wiring is progressing, a high-density pattern with a pitch of about 50 μm is generally used, and the pitch is one digit or more coarse compared to that. In such a situation, for example, when 32 wires are crossed together, two rows of 16 to 40 mm wide spaces are required, and a space of 160 to 400 wires with a pitch of 50 μm is required for 32 wires. This is a sacrifice. For this reason, there are many cases where terminals cannot be arranged in an actual wiring pattern. In addition, since the number of wirings on the intersecting side is not determined, it is necessary to prepare a ceramic multilayer substrate of a size that matches that, and it is often cheaper to multilayer the parent substrate side for ease of use and price. Is the situation.

  Separately, multiple jumper wires that are sandwiched between films and integrated so that the ends of the jumper wires can be exposed have advantages in price and flexibility, but they must be connected at a fine pitch. Is difficult to use for high-density wiring boards. Apart from such general applications, polyimide-based semiconductor device substrates on which a plurality of semiconductor elements are mounted are also drawing attention. Currently, it can only be handled by a substrate with wiring formed on both sides, called 2 metal, or it can be handled by a glass-epoxy substrate with 4 or more layers, and 2 metal products are expensive and are used for handling high-speed signals that require characteristic impedance control. Since sufficient performance cannot be ensured with metal, there are an increasing number of examples that support build-up substrates.

  An object of the present invention is to provide a wiring module that realizes cost reduction by reducing the number of layers of recent printed wiring boards for electronic devices whose wiring is miniaturized, high-density cross wiring, and high ease of use. It is intended to provide a printed wiring board equipped with.

  As a result of studying many materials and processes in consideration of the above problems, it was found that an insulating substrate made of polyimide resin or glass epoxy base material (an insulating base material in which a glass fiber cloth is impregnated with an epoxy resin and thermally processed) is used. It has been found that a wiring module in which wiring for crossing and external connection terminals are formed at both ends thereof is optimal for solving the above problems. Insulating films such as low-cost polyimide and glass epoxy base materials have many achievements in TAB and printed wiring boards, and are easily available. Similarly, there is a track record in wiring formation, and in pattern formation using a polyimide film, 30 μm pitch wiring has already been mass-produced for COF (Chip on Film) liquid crystal driver applications, and the wiring capacity per conductor layer Is much higher than other wiring boards. In addition, if the connection terminal is a general and easy-to-use wire bonding method, connection with a pitch of 100 μm or less is possible. Connection of 30-50 μm pitch by TAB method (Tape Automated Bonding) or COF method is also difficult at present, but it is difficult to connect the connection terminals to each other. It is possible to make it correspond.

  The invention according to claim 1 of the present invention is the wiring module in which the wiring layer is laminated on the surface of the insulating layer, wherein the wiring layer includes a pair of external connection terminals and a wiring connecting the external connection terminals. A wiring module characterized in that a plurality of sets are formed.

  In the invention according to claim 2 of the present invention, a part of the plurality of external connection terminals is concentrated in a certain area of the wiring module, and a part of the external connection terminals paired therewith is another constant area. The wiring module according to claim 1, wherein the wiring module is arranged in a concentrated manner.

  The wiring module includes a plurality of connection terminals corresponding to the connection terminals of the parent board and wirings connecting the connection terminals, thereby supplementing the wiring of the parent board, and a fixed region having one or more connection terminals on the wiring module The fixed area where the connection terminals are concentrated is preferably a plurality of fixed areas that are completely independent of other fixed areas. There is no problem even if some of them overlap for reasons such as terminal layout restrictions.

In the invention according to claim 3 of the present invention, the external connection terminals and the wirings connecting the external connection terminals are arranged at substantially symmetrical positions, and the positions and shapes of some of the external connection terminals or wirings are changed. 3. The wiring module according to claim 1, further comprising a portion whose direction can be discriminated by adding a mark other than the wiring.
It is.

  The wiring and the connection terminal are arranged substantially symmetrically with respect to a substantially central point of the wiring module or a line centered on the point, and the device is devised so that the direction can be easily determined. It can be dealt with by shifting the position at a level where a part of the wiring and the connection terminal can be visually recognized, changing the shape, and attaching a mark other than the wiring and the connection terminal.

  The invention according to claim 4 of the present invention is characterized in that the plurality of external connection terminals and wirings formed on the insulating substrate do not have electrical connection portions to each other in the wiring module. Or a wiring module according to 2.

  The invention according to claim 5 of the present invention is the wiring module in which the wiring layers are laminated on the front surface and the back surface of the insulating layer, wherein the pair of external connection terminals are arranged in different wiring layers, and the external terminals are arranged between the external terminals. 4. The wiring module according to claim 1, wherein the wiring to be connected is conducted through a via wiring formed in a via hole penetrating the insulating layer. 5.

  A wiring module that has wiring on the wiring module only on one side or that has wiring on both sides but does not have each electrical connection in the wiring module and has a low number of layers and an inexpensive structure is shown. Is.

  In the invention according to claim 6 of the present invention, the wiring and the external connection terminal are formed of copper, and the external connection terminal portion is covered with a corrosion-resistant metal or a conductive material such as carbon to protect the wiring portion. 6. The wiring module according to claim 1, wherein an insulating film is formed on a portion other than the connection terminal.

  It shows a wiring module that is easy to obtain and manufacture by using commonly used materials. In addition, the insulating film for protecting the wiring and the conductive material covering the external connection terminal may be completely independent or may overlap.

  The invention according to claim 7 of the present invention is a printed wiring board provided with a pair of connection terminals at a position straddling at least one or more wirings, and the wiring module according to any one of claims 1 to 5 is mounted. By doing so, the connection terminal provided on the printed wiring board and the external connection terminal in the wiring module are connected to complete a desired wiring.

  A printed wiring board with connection terminals corresponding to the external connection terminals of the wiring module. By mounting the wiring module on this, the corresponding terminals between the printed wiring board and the wiring module are connected, and the original wiring is completed. By adopting such a form, the characteristic that the object is achieved without increasing the number of layers of the printed wiring board is shown. In addition, the wiring module is not for connecting a plurality of printed wiring boards, but is fixed on one printed wiring board to complement the wiring.

  The invention according to claim 8 of the present invention is the printed wiring board according to claim 7, wherein the printed wiring board is formed of one wiring layer or two wiring layers.

  Among the printed wiring boards, a printed wiring board having a small number of wiring layers, in which the effect of mounting a wiring module appears significantly, is shown.

  The combination of the wiring module according to the present invention and the printed wiring board corresponding to the wiring module makes it possible for an application that conventionally uses a build-up board to be supported by a combination of a cheaper two-metal tape board and a wiring module. In an example in which a metal tape substrate is used, the number of wiring layers can be reduced, such as a combination of one metal tape substrate and a wiring module, and the overall thickness and cost can be reduced. In particular, the cost is reduced to less than half of the conventional cost by using two metal tapes as one metal. Thus, the cost reduction effect by reducing the number of layers is large with respect to the original substrate having a small number of layers.

  In addition, when a solid ground layer is provided on the back surface of the wiring module and a two-metal board with two wiring layers is used as a one-metal board with one wiring layer, not only the effect of reducing the number of layers but also the crossing wiring Since the shield layer by the wiring module of the present invention can be inserted between them, the crosstalk between the intersecting wirings is greatly reduced, and it becomes possible to cope with higher speed signals.

  Embodiments of the present invention will be described in detail. 1A and 1B are partial views showing a wiring module of the present invention, in which FIG. 1A is a plan view and FIG. 1B is a side sectional view. In FIG. 1A, a plurality of external connection terminals 11 are arranged and arranged on one side of an insulating substrate 14, and a pair of external connection terminals 11 are also arranged on one side. The external connection terminal 11 is electrically connected by a wiring 12. The two external connection terminals 11 at both ends of the wiring 12 are electrically connected to the connection terminals in the wiring circuit of the parent substrate, for example, the printed circuit board, thereby completing the wiring circuit. A cross-sectional view of the xx plane in the figure is shown in FIG. In FIG. 1B, a pair of external connection terminals 11 and wirings 12 are formed only on one side of the substrate 14.

  2A and 2B are partial views showing another wiring module of the present invention, in which FIG. 2A is a plan view and FIG. 2B is a side sectional view. In FIG. 2A, a plurality of external connection terminals 11 are arranged and arranged on one side of the insulating substrate 14, and a pair of external connection terminals 11 are also arranged on one side. The external connection terminal 11 is electrically connected by a wiring 12. The two external connection terminals 11 at both ends of the wiring 12 are electrically connected to the connection terminals in the wiring circuit of the parent substrate, for example, the printed circuit board, thereby completing the wiring circuit. A cross-sectional view of the xx plane in the figure is shown in FIG. In FIG. 2B, a pair of external connection terminals 11 and wirings 12 are formed on both surfaces of the substrate 14. That is, the wiring module of the present invention in which front and back two-layer wiring is formed.

  3A and 3B are partial views showing still another wiring module of the present invention, in which FIG. 3A is a plan view and FIG. 3B is a side sectional view. In FIG. 3A, a plurality of external connection terminals 11 are arranged and arranged on one side of the surface of the insulating substrate 14, and a pair of via pads 13 are also arranged on one side. The via pad 13 is electrically connected to the external connection terminal 11 by a wiring 12. The via pad 13 is electrically connected to the external connection terminal 11 disposed on the back surface through a via penetrating the wiring module substrate (not shown in the figure). A cross-sectional view of the xx plane in the figure is shown in FIG. In FIG. 3B, the external connection terminals 11 are arranged on both the front and back surfaces of the substrate 14, the via 15 is formed at the position of the via pad 13, and the external connection terminal 11 on the front surface and the external connection on the back surface through the via 15. The terminal 11 is electrically connected by the wiring 12. That is, the wiring module of the present invention in which the external connection terminals 11 are formed on the front and back surfaces.

  Hereinafter, specific examples of the present invention will be described.

FIG. 4 is a partially enlarged view for explaining the connection between the wiring module and the parent board of Example 1, (a) is a plan view of the surface of the wiring module, and (b) is a plan view of the parent board. (C) is a top view of the state which aligned and bonded together, (d) is a sectional side view in which the wiring module and the parent substrate were connected. Prepare a material that is coated with an adhesive with a thickness of 12 μm on one side of a polyimide tape (UPILEX S, trade name, manufactured by Ube Industries Co., Ltd.) with a thickness of 48 mm and a thickness of 50 μm, and near the widthwise end of the polyimide tape A sprocket hole was drilled in the mold. A copper foil having a width of about 42 mm and a thickness of 12 μm was laminated on the center of the polyimide tape, and the adhesive was cured by placing it in an oven in which the temperature gradually increased to about 180 ° C. After the copper foil surface was washed with acid and dried, a positive liquid resist (PMER-P (trade name), manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied on the copper foil to a thickness of about 5 μm and dried. A desired resist having an external connection terminal and a wiring pattern connected thereto by projecting and developing with an exposure mask having an external connection terminal having a width of 80 μm and a light-shielding portion and a transmission portion with a gap of 20 μm. A pattern was formed. The ferric chloride solution was sprayed to remove the exposed copper from the resist opening, the resist was stripped with a sodium hydroxide solution, and the surface was subjected to electrolytic gold plating to protect the external connection terminals and wiring. Through the above process, a wiring module including the external connection terminal 11 having a copper pattern with a width of about 80 μm and a gap with a width of about 20 μm and a line-symmetrical wiring 12 connected to the external connection terminal 11 was formed (see FIG. 4A).

  Next, an insulating tape-like adhesive (APAS 1592, trade name, manufactured by Sumitomo 3M Co., Ltd.) is laminated on the back surface of the wiring module 10, punched with a mold and separated into individual pieces, and external connection terminals Then, the direction is determined with reference to the fact that the wiring is close to one side, and the wiring is aligned and pasted on the parent substrate 20 in which the wiring is formed on one side prepared separately (see FIGS. 4B and 4C). ). A single-sided printed wiring board having wiring intersections by the wiring module was manufactured by connecting the external connection terminal 11 of the wiring module and the corresponding connection terminal 21 of the parent board by wiring 25 of wire bonding (FIG. 4D). reference).

  FIGS. 5A and 5B are partial enlarged views for explaining the connection between the wiring module and the parent board of the second embodiment. FIG. 5A is a plan view of the surface of the wiring module, and FIG. 5B is a plan view of the parent board. (C) is the top view which aligned and bonded together, (d) is a sectional side view which connected the wiring module and the parent board. Prepare a material (Gould Flex, trade name, manufactured by Japan Energy Co., Ltd.) that has a copper layer with a thickness of 12 μm on both sides of a polyimide tape with a width of 48 mm and a thickness of 50 μm. Sprocket holes were drilled with a mold. After the copper foil surface was washed with acid and dried, a positive liquid resist (PMER-P (trade name), manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied on the copper foil to a thickness of about 5 μm and dried. A desired resist having an external connection terminal and a wiring pattern connected thereto by projecting and developing with an exposure mask having an external connection terminal having a width of 80 μm and a light-shielding portion and a transmission portion with a gap of 20 μm. A pattern was formed. After the PET film was bonded to the back surface, a ferric chloride solution was sprayed to remove copper exposed from the resist opening, and the resist was peeled off with a sodium hydroxide solution. After removing the chromium layer remaining on the polyimide surface after etching with a potassium permanganate solution, the surface was subjected to electrolytic gold plating to protect the external connection terminals and wiring with gold. The back PET film was peeled off to expose the back copper layer. Finally, the wiring module is provided with an external connection terminal 11 comprising a copper pattern having a width of about 80 μm and a gap having a width of about 20 μm, a wiring 12 connected to the external connection terminal 11 and a mark for marking by punching with a die and separating into individual pieces. 10 was formed (see FIG. 5A).

  Next, a conductive paste (DBC120DV, trade name, manufactured by Panasonic Factory Solutions Co., Ltd.) is applied to the back surface of the wiring module 10 with a dispenser, and aligned on a separately prepared parent substrate on which wiring is formed on both sides. They were pasted together (see FIGS. 5B and 5C). By hardening the conductive paste, electrical connection with the ground pattern 22a of the parent substrate and bonding of the wiring module were performed at the same time.

  By connecting the connection terminal 21 of the printed wiring board corresponding to the external connection terminal 11 of the wiring module by the wiring 25 of the wire bonding, the electrical interference between the signal line formed on the parent substrate and the wiring of the wiring module shape is prevented. There was almost no double-sided printed wiring board corresponding to high-speed signals having wiring intersections with the mounted wiring module (see FIG. 5D).

6A and 6B are partial enlarged views for explaining the connection between the wiring module and the parent board of the third embodiment. FIG. 6A is a plan view of the front surface of the wiring module, and FIG. 6B is a plan view of the back surface of the wiring module. FIG. 3C is a side sectional view of the wiring module and the parent substrate connected to each other. Prepare a material in which a polyimide tape with a thickness of 12 μm is coated on one side of a polyimide tape (UPILEX S, trade name, manufactured by Ube Industries Co., Ltd.) having a width of 48 mm and a thickness of 50 μm. A sprocket hole and a via for connecting a solder ball were drilled with a mold. Thereafter, a wiring pattern was formed in substantially the same process as in Example 1 except that a PET film was attached to the back surface and etched, and the PET film was peeled off. At this time, a dummy land for specifying the direction was provided in the wiring pattern.

  Next, solder balls were inserted into the via holes 16 on the back surface of the wiring module and reflowed to form solder balls as external connection terminals. A wiring module is aligned on a separately prepared parent board and reflowed again to connect the external connection terminal 11 of the wiring module and the connection terminal 21 of the corresponding printed wiring board. The printed wiring board which has a part was manufactured (refer FIG.6 (c)).

  FIG. 7 is a partially enlarged view for explaining the connection between the wiring module and the parent substrate of Example 4, wherein (a) is a plan view of the surface of the wiring module, and (b) is a wiring module and the parent substrate. FIG. The wiring module 10 manufactured by the same process as in Example 3 except that the via for ball connection is not formed is bonded to the upper surface of the semiconductor element 30 that is flip-chip connected to the parent substrate 20 with the insulating adhesive 8. The external connection terminal 11 on the wiring module and the connection terminal 21 of the parent substrate were connected by wire bonding wiring 25 and sealed with resin (see FIG. 7B).

  In another example, a material (Gould Flex, trade name, manufactured by Japan Energy Co., Ltd.) in which a copper layer having a thickness of 12 μm is formed on one side of a polyimide tape having a width of 70 mm and a thickness of 50 μm is prepared. A sprocket hole was drilled with a mold near the end in the direction. After the copper foil surface was washed with acid and dried, a positive liquid resist (PMER-P (trade name), manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied on the copper foil to a thickness of about 5 μm and dried. Projection exposure was performed with an exposure mask for a parent substrate provided with a light-shielding portion of the connection terminal and the wiring pattern and a transmission portion around the connection terminal, and development was performed, thereby forming a desired resist pattern having the external connection terminal and the wiring pattern connected thereto. . The ferric chloride solution was sprayed to remove copper exposed from the resist opening, and the resist was stripped with a sodium hydroxide solution. After removing the chromium layer remaining on the polyimide surface after etching with the potassium permanganate solution, the cover resist 1 was printed, and the connection terminal 21 was subjected to electrolytic gold plating to complete the parent substrate. Moreover, the wiring module was similarly formed using the same polyimide tape. A tape-like adhesive having a thickness of 12 μm was laminated on the back surface of the parent substrate, and a heat sink having a thickness of 100 μm was aligned and bonded, and then the wiring module was similarly aligned and bonded to the parent substrate. After die bonding of the semiconductor element, the electrode of the semiconductor element whose thickness is cut to 100 μm and the connection terminal of the parent board are connected by wire bonding, and at the same time, the external connection terminal of the wiring module and the connection terminal of the parent board are connected by wire bonding. did. At this time, the semiconductor element and the wiring module are arranged so as not to overlap each other. Finally, the surface on which the semiconductor element was mounted was collectively transfer molded to complete the card type memory module. The total thickness of the substrate at this time was less than 80 μm, and the thickness of the substrate was reduced to ¼ or less compared to the thickness of 340 μm in the conventional configuration using the four-layer substrate.

It is the fragmentary figure which shows the wiring module of this invention, (a) is a top view, (b) is a sectional side view. It is the fragmentary figure which shows the wiring module of this invention, (a) is a top view, (b) is a sectional side view. It is the fragmentary figure which shows the wiring module of this invention, (a) is a top view, (b) is a sectional side view. BRIEF DESCRIPTION OF THE DRAWINGS It is the elements on larger scale explaining the connection of the wiring module of Example 1 of this invention, and a parent board, (a) is a top view of the surface of a wiring module, (b) is a top view of a parent board, (c) is a plan view of the alignment and pasting, and (d) is a side sectional view of the wiring module and the parent substrate connected to each other. It is the elements on larger scale explaining the connection of the wiring module of Example 2 of this invention, and a parent board, (a) is a top view of the surface of a wiring module, (b) is a top view of a parent board, (c) is a plan view of the alignment and bonded together, and (d) is a side sectional view of the wiring module and the parent substrate connected to each other. It is the elements on larger scale explaining the connection of the wiring module of Example 3 of this invention, and a parent board, (a) is a top view of the surface of a wiring module, (b) is a top view of the back surface of a wiring module. (C) is the sectional side view which connected the wiring module and the main board | substrate. It is the elements on larger scale explaining the connection of the wiring module of Example 4 of this invention, and a mother board, (a) is a top view of the surface of a wiring module, (b) is the connection of a wiring module and a mother board. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Cover resist 2 ... Opening part 8 of cover resist layer ... Insulating adhesive 9 ... Conductive adhesive 10 ... Wiring module 11 ... External connection terminal 11a ... (on the back surface) External connection terminal 12 ... Wiring 12a ... (on the back surface) ) Wiring 13 ... via pad 14 ... insulating substrate 15 ... via 16 ... via hole 17 ... solder ball 20 ... parent substrate 21 ... (parent substrate) connection terminal 22 ... (parent substrate) wiring 22a ... (parent substrate) ) Ground pattern 24... (Insulating substrate) 25 (parent substrate)... Wire bonding wiring 30... Semiconductor element 31.

Claims (8)

  In a wiring module in which a wiring layer is laminated on the surface of an insulating layer, the wiring layer includes a plurality of pairs each including a pair of external connection terminals and a wiring connecting the external connection terminals. A featured wiring module.   A part of the plurality of external connection terminals is concentrated in a certain area of the wiring module, and a part of the external connection terminal paired therewith is concentrated in another constant area. The wiring module according to claim 1.   The external connection terminals and the wiring that connects them are arranged in almost symmetrical positions, changing the position and shape of some of the external connection terminals or wiring, or adding a mark other than the external connection terminals or wiring in that direction The wiring module according to claim 1, wherein the wiring module has a distinguishable portion.   The wiring module according to claim 1 or 2, wherein the plurality of external connection terminals and wirings formed on the insulating substrate do not have electrical connection portions to each other in the wiring module.   In the wiring module in which wiring layers are laminated on the front surface and the back surface of the insulating layer, the pair of external connection terminals are arranged in different wiring layers, and the wiring connecting the external terminals is a via penetrating the insulating layer. 4. The wiring module according to claim 1, wherein the wiring module is electrically connected through a via wiring formed in the hole.   The wiring and the external connection terminal are formed of copper, the external connection terminal portion is covered with a corrosion-resistant metal or a conductive material such as carbon, and an insulating film for protecting the wiring portion is a portion other than the connection terminal The wiring module according to claim 1, wherein the wiring module is formed as described above.   In the printed wiring board which provided the connecting terminal used as a pair in the position which straddles at least 1 or more wiring, by mounting the wiring module of any one of Claims 1 thru | or 5, the said provided in the printed wiring board A printed wiring board comprising: a connection terminal connected to an external connection terminal in the wiring module to complete a desired wiring.   The printed wiring board according to claim 7, wherein the printed wiring board is formed of one wiring layer or two wiring layers.

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