JP2002324964A - Multi-unit wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that an automatic machine for mounting electronic parts misreads a defective wiring board region as a normal wiring board region, and as a result, a defective electronic device is manufactured. SOLUTION: In a multi-unit wiring board, a plurality of wiring board regions 2 are arranged with a plurality of metal bumps 6 for connecting electrodes of electronic parts on an upper face of an insulation base 4, and the regions 2 are integrally and vertically laterally arrayed in a sheet-like mother board 1. A defective wiring board region 2D of the respective wiring board regions 2 is flattened so that at least one 6M of the metal bumps 6 has a height of 3/4 of the other metal bumps 6. The flattened metal bump 6M is measured by a height measuring device, whereby go or no go of the respective wiring board regions 2 can be reliably determined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a large number of wiring board regions, which are used as wiring boards for mounting electronic components such as semiconductor elements and piezoelectric vibrators, arranged in a matrix on a wide area. The present invention relates to a multi-cavity wiring board.

[0002]

2. Description of the Related Art A wiring board for mounting an electronic component such as a semiconductor element or a piezoelectric vibrator is formed, for example, on an insulating base made of a substantially square plate-like ceramic on which an electronic component is mounted at the center of the upper surface. A plurality of metallized wiring conductors extending from the upper surface to the lower surface of the base are arranged. The portion of the metallized wiring conductor protruding on the upper surface of the insulating base is an electronic component connection pad to which electrodes of the electronic component are electrically connected, and the portion protruding on the lower surface of the insulating base is an external connection connected to an external electric circuit board. Pads are formed. In addition,
The electrical connection between the electrodes of the electronic component and the electronic component connection pads of the wiring board has recently been made through metal bumps made of solder, gold, or the like, and via such metal bumps. In general, metal bumps are generally attached to respective electronic component connection pads of a wiring board in advance to facilitate connection. Then, each electrode of the electronic component is electrically and mechanically connected to the electronic component connection pad of the wiring board via a metal bump previously attached thereto, and then the electronic component is covered on the upper surface of the wiring board. Then, a sealing resin or a lid is fixed, and the electronic component is hermetically sealed, whereby an electronic device as a product is obtained.

Incidentally, such a wiring board has recently become extremely small with a size of about several mm square in accordance with a recent demand for miniaturization of electronic devices. And in order to make such a miniaturized wiring board easy to handle and high in manufacturing efficiency,
It is manufactured in the form of a so-called multi-cavity wiring board in which a large number of small wiring boards are simultaneously and intensively obtained from one large-area mother board.

In such a multi-cavity wiring board, a large number of wiring board areas, each of which is a small wiring board, are divided by dividing lines in a large-area mother board, and are vertically and horizontally arranged integrally. In each wiring board region, a wiring conductor extending from the upper surface to the lower surface is formed, and a metal bump is attached to an electronic component connection pad of the wiring conductor. Then, the electronic component is mounted and fixed on each wiring board area so that each electrode thereof is electrically connected to the electronic component connection pad via a metal bump, and each wiring board area is covered so as to cover this electronic component. A sealing resin or a lid is fixed on the upper surface of the substrate, and thereafter, the mother substrate is divided along the dividing lines, whereby a large number of electronic devices are manufactured simultaneously and intensively.

[0005] In such a multi-cavity wiring board, in order to mount electronic parts on each wiring board area, for example, an automatic machine equipped with a three-dimensional dimension measuring device using laser light is used. The positions and heights of the metal bumps in each wiring board area are measured by a three-dimensional dimension measuring device of an automatic machine, and based on the information, each electrode of the electronic component and the metal bumps are aligned and mounted automatically. The method has been adopted.

[0006]

However, according to such a multi-cavity wiring board, some of the large number of wiring board regions arranged and formed in the mother board due to manufacturing variations and defects. In some cases, a defective wiring board region having a defect such as disconnection, short circuit, adhesion of foreign matter, dirt, stain, scratch, chipping or the like may be included. When such a defective wiring board area is included, a mark is made on the upper surface of the defective wiring board area with, for example, an oil-based paint, and the mark is recognized by a three-dimensional dimension measuring device. When an electronic component is mounted on the wiring board area by an automatic machine, the marked wiring board area is determined to be defective, and the defective wiring board area is programmed so as not to mount the electronic component. I was

However, when a mark is made with an oily paint on the upper surface of the defective wiring board area, if the paint is thin and the thickness is insufficient, the mark can be reliably recognized by the three-dimensional dimension measuring device. In some cases, an automatic machine may mistake a defective wiring board area as a normal wiring board area and mount electronic components on the defective wiring board area. In this case, a defective electronic device is manufactured. Had the problem that

The present invention has been devised in view of such a conventional problem, and has as its object to prevent the mounting of electronic components in a defective wiring board area and to provide a large number of non-defective electronic devices only. Another object of the present invention is to provide a multi-piece wiring board that can be manufactured simultaneously and intensively.

[0009]

A multi-piece wiring board according to the present invention comprises a plurality of wiring board areas, each of which has a plurality of metal bumps on an upper surface of an insulating base to which electrodes of electronic components are connected, and is provided with a plurality of wiring board areas. A multi-cavity wiring board formed integrally and vertically arranged in a matrix mother board, of each wiring board area,
The defective wiring board region is characterized in that at least one of the metal bumps is crushed so as to have a height of ３ or less of the other metal bumps.

According to the multi-cavity wiring board of the present invention, the defective wiring board area is crushed so that at least one of the metal bumps is ３ or less the height of the other metal bumps. By measuring the crushed metal bumps with a three-dimensional dimension measuring apparatus of an automatic machine, it is possible to reliably determine whether or not the area is a defective wiring board area.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a multi-cavity wiring board according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a top view showing an embodiment of a multi-cavity wiring board according to the present invention, and FIG. 2 is a cross-sectional view. In these figures, 1 is a ceramic mother board, and 2 is a wiring board area. It is.

The ceramic mother substrate 1 is a substantially rectangular flat plate made of a ceramic material such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, or a glass-ceramic. A large number of wiring board regions 2 each of which becomes a small wiring board are partitioned by virtual dividing lines 3 and are integrally arranged vertically and horizontally.

Each wiring substrate region 2 arranged and formed on the ceramic mother substrate 1 has an insulating base 4 made of a ceramic material.
A plurality of metallized wiring conductors 5 made of metal powder of metal such as tungsten, molybdenum, copper, silver or the like are arranged from the upper surface to the lower surface.

The insulating substrate 4 functions as a supporting member for supporting the electronic components and also as a holding member for electrically insulating and holding the metallized wiring conductors 5 from each other, and the electronic components are mounted on the upper surface thereof. Is done.

The metallized wiring conductor 5 functions as a conductive path for electrically connecting an electronic component mounted on the upper surface of the insulating base 4 to an external electric circuit board.
An electronic component connection pad 5a connected to an electrode of an electronic component is formed on a portion led out on the upper surface of the substrate, and an external connection pad 5b connected to an external electric circuit is formed on a portion led out on a lower surface of the insulating base 4.

Further, a metal bump 6 made of, for example, a solder such as a lead-tin alloy or a silver-tin alloy, gold, or the like is attached to the electronic component connection pad 5a of each wiring board region 2.

The metal bump 6 functions as a connecting member for electrically and mechanically connecting the electrode of the electronic component and the metallized wiring conductor 5. The components are mounted and fixed on each wiring board area 2 and the electrodes of the electronic components and the metallized wiring conductors 5 are electrically connected.

Incidentally, such a ceramic mother substrate 1
For example, an appropriate punching process is performed on the ceramic green sheet, and a metallized paste for the metallized wiring conductor 5 is printed and applied on the ceramic green sheet in a predetermined pattern by a screen printing method, and then fired at a high temperature. When the metal bump 6 is made of, for example, solder, the metal component 6 is coated with a metal having excellent wettability with solder, such as nickel or gold, on the electronic component connection pad 5a by a plating method, and a ball-shaped metal bump 6 is formed thereon. When the solder is made of gold, for example, a nickel plating layer is formed on the electronic component connection pad 5a by placing the solder in the form of paste or paste, heating and melting the solder at a temperature equal to or higher than the melting temperature of the solder, and then cooling. It is attached by applying a gold plating layer as a base to a thickness of about 10 to 100 μm.

In the multi-cavity wiring board of the present invention, if there is a defective wiring board area 2D among the wiring board areas 2 arranged and formed on the ceramic mother substrate 1, the defective wiring board area One of the metal bumps 6M in the region 2D is crushed so as to be 3/4 or less the height of the other metal bumps 6. In this example, one 6M of the metal bumps 6 in the defective wiring board area 2D is crushed, but two or more of the metal bumps 6 in the defective wiring board area 2D may be crushed. Absent. As described above, since at least one of the metal bumps 6M of the defective wiring board area 2D is crushed so as to have a height of 3/4 or less of the other metal bumps 6, the mounting of each wiring board area 2 is performed. When electronic parts are mounted on the part 4a by an automatic machine, the height of the metal bumps 6 of each wiring board area 4 is measured by a three-dimensional dimension measuring device of the automatic machine, so that the automatic machine can use the wiring board area 2
Can be reliably determined, and as a result, no electronic component is mounted on the defective wiring board area 2D.

The height of the crushed metal bump 6M in the defective wiring board area 2D is 3/3 of the height of the other metal bumps 6.
If it exceeds 4, it will be difficult to reliably determine the difference in height when measuring with a three-dimensional dimension measuring device. Therefore, it is specified that the crushed metal bump 6M in the defective wiring board region 2D is crushed so as to have a height of ／ or less of the other metal bumps 6.

Further, in order to crush the metal bumps 6 in the defective wiring board area 2D, the metal bumps 6 are softened by heating at a temperature lower than the melting temperature of the metal bumps 6 by, for example, a heating device using a pulse heating method. For example, a method of pressing the softened metal bump 6 from above with a metal bar having a flat lower surface is adopted.

After the electronic components are mounted on all of the normal wiring board regions 2, the upper surface of each of the wiring substrate regions 2 on which the electronic components are mounted is covered with a sealing resin or lid so as to cover the electronic components. After fixing the body, the ceramic motherboard 1
Is divided along the division line 3, only a large number of non-defective electronic devices are manufactured simultaneously and collectively. In order to divide the ceramic mother substrate 1, a method of cutting the mother substrate 1 along a division line 3 using a diamond cutter or a laser cutter to divide the ceramic mother substrate 1 is adopted. Alternatively, the mother board 1
A dividing groove is formed by making a small cut along the dividing line 3 on the upper surface and / or lower surface of the ceramic green sheet for use, and a method of breaking along the dividing groove is adopted.

The present invention is not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present invention.

[0025]

According to the multi-cavity wiring board of the present invention,
Since the defective wiring board region is crushed so that at least one of the metal bumps has a height of 高 or less of the other metal bumps, the crushed metal bump is measured by a three-dimensional dimension measuring apparatus of an automatic machine. By performing the measurement, it is possible to reliably determine whether or not the area is a defective wiring board area. As a result, electronic components are not mounted on the defective wiring board area, and therefore, only a large number of good electronic devices are provided. It is possible to manufacture individual and simultaneous intensive products.

[Brief description of the drawings]

FIG. 1 is a top view showing an example of an embodiment of a multi-cavity wiring board according to the present invention.

FIG. 2 is a sectional view of the multi-cavity wiring board shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Mother board 2 ... Wiring board area 2D ... Defective wiring board area 4 ... Insulating base 6 ... Metal bump 6M ... Crushed metal bump

Claims (1)

[Claims] 1. A large number of wiring board regions each having a plurality of metal bumps to which electrodes of an electronic component are connected on an upper surface of an insulating base are integrally and vertically arranged in a plate-shaped mother substrate. A multi-cavity wiring board, wherein a defective wiring board area of each of the wiring board areas is crushed so that at least one of the metal bumps has a height of ／ or less of the other metal bumps. A multi-cavity wiring board characterized in that: