JPH04299839A - Circuit wiring board provided with intermediate terminal for circuit-component connection and its manufacture - Google Patents

Abstract

PURPOSE:To provide a circuit wiring board provided with an intermediate terminal for circuit-component connection which is constituted so as to be capable of absorbing a starin caused by the difference in a coefficient of thermal expansion between a circuit component and the circuit wiring board by providing the intermediate terminal arranged and mounted between the circuit component such as an IC chip or the like and the circuit wiring board and to provide a manufacturing method suitable for it when the circuit component is mounted on the circuit wiring board. CONSTITUTION:The following are provided: a circuit wiring board provided with a pad 3, for connection use, which is bonded electrically to a circuit wiring board 2 formed on one face of an insulating base material 1; and an intermediate terminal 4, for circuit-component connection use, which is provided with a solder bump 8 for connection use and with a pad 10 for connection use which are passed individually through island-shaped base materials 7, 9 formed on both faces of an island-shaped electrode 6 and which are bonded individually to the island-shaped electrode 6. The intermediate terminal 4 for circuit-component connection use is mounted on the circuit wiring board in such a way that the solder bump 8 for connection use is connected to the pad 3 for connection use of the circuit wiring board.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is a method of flip-chip mounting circuit components such as ICs on a circuit wiring board using solder bumps, etc., in order to improve the bonding reliability of the bumps. The present invention relates to a circuit wiring board provided with intermediate terminals for connecting circuit components disposed between the circuit board and a method for manufacturing the same.

0002

[Background Art] In recent years, the area of ICs has become larger and the number of electrodes has increased.
As density increases, the difference in coefficient of thermal expansion between circuit components such as IC chips and circuit boards causes distortion in bump portions and, in severe cases, may cause disconnection, which adversely affects connection reliability. To solve this problem, an effective method is to increase the height of the bump by arranging this type of circuit component mounting intermediate board between the circuit component and the circuit board.

Various conventional structures have been proposed for such intermediate boards with terminals for connecting circuit components. - A conductive pin of about 0.2 mm is embedded in the insulating material so as to protrude from the insulating material, and a hole is formed at a predetermined position in the insulating film as in JP-A-1-72537. a certain amount of pages
There is one in which solder strips are held by printing means. Furthermore,
As shown in Japanese Unexamined Patent Publication No. 62-18049, a through hole is formed in a ceramic green sheet and fired, and copper paste or the like which is wettable with solder is inserted into the through hole. Next, a non-wettable tungsten paste or the like is inserted on top of this copper layer and fired, then a wettable copper paste or the like is inserted on top of the tungsten layer and fired, and the final Another method is to melt and bond a solder ball to the copper part of the upper surface.

0004

[Problems to be Solved by the Invention] In such intermediate substrates for mounting circuit components, as the wiring density of IC chips becomes higher and the diameter of the solder bumps decreases accordingly, it becomes necessary to use high-definition connection terminals. It becomes difficult to manufacture an intermediate board for mounting circuit components having the above-mentioned characteristics. Furthermore, it becomes increasingly difficult to align the electrodes of the IC chip and the connection terminals of the intermediate board for mounting circuit components.

On the other hand, in the conventional method, the difference in the coefficient of thermal expansion of the insulating base material existing between each connection terminal causes distortion in the connection terminals made of solder, etc., so circuit components will become more dense and larger in the future. This may make reliable implementation difficult.

[0006]

[Means for Solving the Problems] The present invention improves reliability by suitably absorbing distortion caused by a difference in coefficient of thermal expansion between the circuit components and the circuit board when mounting circuit components such as IC chips on a circuit board. The present invention provides a circuit wiring board equipped with intermediate terminals for connecting circuit components, which enables high-performance flip-chip mounting, and a method for manufacturing the same.

For this reason, in the circuit wiring board provided with intermediate terminals for connecting circuit components of the present invention, an island-shaped insulating base material is provided on one side of the island-shaped electrode, and one end of the island-shaped electrode is electrically connected. an intermediate terminal for connecting a circuit component configured to be connected to the insulating base material and having a connecting solder bump whose other end protrudes to the outside through the island-shaped insulating base material; has a required circuit wiring pattern, one end of which is electrically connected to the circuit wiring pattern, and the other end of which extends through the insulating base material and protrudes to the outside. The circuit wiring board is provided with a circuit wiring board configured as shown in FIG. It is configured such that terminals are arranged in at least one stage.

[0008] Here, in the intermediate terminal for connecting circuit components, another island-shaped insulating base material is provided on the other side of the island-shaped electrode, and one end thereof is electrically connected to the island-shaped electrode. It is also possible to provide another connection pad whose other end protrudes to the outside through the other island-shaped insulating base material. It is preferable that the melting temperature of the connecting solder bumps of the intermediate terminal for connecting circuit components as described above is higher than the melting temperature of the solder bumps formed on circuit components such as ICs. The solder bumps for connection as described above can be provided on the circuit wiring board side or on the intermediate terminal side for connecting circuit components, and in this case, the terminals to be bonded to such solder bumps for connection are A pad structure having a ring-shaped protuberance on the outer periphery is suitable for terminal alignment.

[0009] Furthermore, as a method for manufacturing a circuit wiring board equipped with intermediate terminals for connecting circuit components as described above,
Arranged between the circuit component and the circuit wiring board so as to electrically connect the electrode of the circuit component such as an IC to the circuit wiring pattern of the circuit wiring board disposed opposite to the electrode. manufacturing an intermediate board for mounting a circuit component, which has an intermediate terminal for connecting a circuit component formed to electrically connect a first surface and a second surface of an insulating base material; After mounting at least one stage of the intermediate board for mounting circuit components on the circuit wiring board, the intermediate board for mounting circuit components is formed by irradiating excimer laser light onto the intermediate board for mounting circuit components. A step of removing the insulating base material between the intermediate terminals for connecting each circuit component can be adopted.

0010

[Embodiments] The present invention will be further explained below with reference to the illustrated embodiments. Fig. 1 conceptually shows the main parts of a circuit wiring board equipped with intermediate terminals for connecting circuit components according to an embodiment of the present invention. FIG. In the figure, reference numeral 1 is an insulating base material such as polyimide, which has a required circuit wiring pattern 2 on one side, and this circuit wiring pattern 2.
One end is electrically connected to the insulating bar, and the other end is connected to the insulating bar.
A connection pad 3 is formed to penetrate the base material 1 and protrude to the outside. A circuit component connecting intermediate terminal 4, which will be described below, is connected to the connecting pad 3 so as to be electrically conductive to the circuit wiring pattern 2 via the connecting pad 3. Such a connection pad 3 can have a structure in which its outer peripheral portion is raised in a ring shape as shown in the figure. A surface protective layer 5 is formed on the surface of the circuit wiring pattern 2 by laminating a polyimide film with adhesive or by coating with polyimide varnish.

The intermediate terminal 4 for connecting circuit components has an island-shaped electrode 6 made of a conductive metal such as copper foil, and a first island-shaped electrode made of polyimide or the like is provided on the first surface of the island-shaped electrode 6. An insulating base material 7 is provided, one end of which is electrically connected to the first surface of the island-shaped electrode 6, and the other end extends through the first island-shaped insulating base material 7 and projects to the outside. It has a solder bump 8 for connection such as solder, and this solder bump 8 is connected to the connection pad 3 of the circuit wiring board. Furthermore, a second island-shaped insulating base material 9 made of polyimide or the like is provided on the second surface of the island-shaped electrode 6, and one end is electrically connected to the second surface of the island-shaped electrode 6. and a second connection pad 10 whose other end protrudes outside through the second island-shaped insulating base material 9, and this connection pad 10 has a ring-shaped protuberance on its outer periphery. is configured to do so.

FIG. 2 shows a connection configuration diagram between a circuit wiring board having the above-described intermediate terminals for connecting circuit components and an IC chip with solder bumps. In the figure, 11 indicates an IC chip, and 12 are solder bumps connected to the electrodes of the IC chip 11, and these solder bumps 12 are connected to the connection pads 10 of the intermediate terminals 4 for connecting circuit components. Since the melting temperature of the solder bumps 12 provided on the IC chip 11 side is lower than that of the connecting solder bumps 8 of the circuit component connecting intermediate terminals 4, the IC chip 11 as a circuit component It is possible to stably mount circuit components without melting the connection solder bumps 8 of the circuit component connection intermediate terminals 4 even depending on the temperature when mounting the circuit component on a circuit wiring board.

FIGS. 3(1) and 3(2) show one manufacturing process diagram of a circuit wiring board provided with the intermediate terminal 4 for connecting circuit components of the above embodiment. As shown in FIG. 1 (1), first, a circuit wiring board 21 is manufactured so as to include an insulating base material 1, a circuit wiring pattern 2, a connection pad 3, and a surface protection layer 5.
An intermediate substrate 22 for mounting circuit components is manufactured, on which an insulating base material 7A of a required size is formed, in which the first island-shaped insulating base material 7 of the intermediate terminal 4 for connecting circuit components is uniformly continuous, and then the circuit component mounting intermediate board 22 is manufactured. The circuit component mounting intermediate board 22 is mounted on the circuit wiring board 21 by a normal method in such a manner that the solder bumps 8 of the circuit component mounting intermediate board 22 are connected to the connection pads 3 of the wiring board 21. Therefore, when the metal mask 23 is placed above the circuit component mounting intermediate board 22 and the excimer laser beam A is irradiated from above the metal mask 23, as shown in FIG. Since the insulating base material existing between the terminals 4 can be removed by ablation, it is possible to form an island-shaped insulating base material 7 on the intermediate terminal 4 for connecting circuit components, and ultimately separate the insulating base material 7. By removing the metal mask 23 of the body and the unnecessary burrs 24 of the insulating base material, a circuit wiring board having intermediate terminals 4 for connecting circuit components as shown in FIG. 1 can be manufactured.

When removing unnecessary portions of the insulating base material 7A as described above, a separate metal mask 23 is used.
In addition to methods that use excimer laser light to ablate only unnecessary parts, there is also a method of focusing and projecting excimer laser light to ablate only unnecessary parts, and rectangular excimer laser light is applied to the entire surface of the intermediate board 22 for mounting circuit components from above. A method of irradiating light over a wide area can also be adopted.

[0015]

[Effects of the Invention] The circuit wiring board provided with the intermediate terminal for connecting circuit components according to the present invention can be constructed so that no insulating base material is present around the intermediate terminal for connecting circuit components.
It is possible to suitably absorb the strain caused by the difference in thermal expansion coefficient between circuit components such as ICs and circuit wiring boards, making it possible to achieve highly reliable connections with large-area circuit components. be.

Furthermore, according to the manufacturing method of the present invention, a large number of intermediate terminals for connecting circuit components can be bonded to a circuit wiring board at one time, so that it is possible to efficiently manufacture a circuit wiring board equipped with such intermediate terminals for connecting circuit components. It can be manufactured stably.

[Brief explanation of drawings]

FIG. 1 is a conceptual enlarged cross-sectional perspective view of essential parts of a circuit wiring board equipped with intermediate terminals for connecting circuit components, constructed according to an embodiment of the present invention.

FIG. 2 is a conceptual enlarged cross-sectional perspective view of essential parts showing an example of connection and mounting between a circuit wiring board equipped with intermediate terminals for connecting circuit components of the present invention and an IC chip;

[Fig. 3] (1) and (2) of Fig. 3 are manufacturing process diagrams of a circuit wiring board equipped with intermediate terminals for connecting circuit components according to an embodiment of the present invention.

[Explanation of symbols]

1 Insulating base material 2 Circuit wiring pattern 3 Connection pad 4 Intermediate terminal for connecting circuit components 5　　　　　Surface protective layer 6 Island-shaped electrode 7 First island-shaped insulating base material 8 Solder bump for connection 9 Second island-shaped insulating base material 10 Other connection pads 11 IC chip 12 Solder bump 21 Circuit wiring board 22 Intermediate board for mounting circuit components 23 Separate metal mask 24 Bali

Claims (4)

[Claims] Claim 1: An island-shaped insulating base material is disposed on one side of an island-shaped electrode, one end of which is electrically connected to the island-shaped electrode, and the other end of which is connected to the island-shaped insulating base material. An intermediate terminal for connecting a circuit component configured to have a solder bump for connection that penetrates and protrudes to the outside, has a required circuit wiring pattern on an insulating base material, and has a required circuit wiring pattern on the insulating base material. a circuit wiring board configured such that one end thereof is electrically connected to the insulating base material and the other end thereof has a connection pad penetrating the insulating base material and projecting to the outside; putter
a circuit component connecting intermediate terminal configured to arrange at least one stage of the circuit component connecting intermediate terminal on the circuit wiring board so that the circuit component connecting intermediate terminal is electrically conductive between the circuit component connecting intermediate terminal and the circuit component connecting intermediate terminal; circuit wiring board. 2. Another island-shaped insulating base material is provided on the other side of the island-shaped electrode in the intermediate terminal for connecting circuit components, and one end thereof is electrically connected to the island-shaped electrode. 2. A circuit wiring board equipped with intermediate terminals for connecting circuit components according to claim 1, further comprising another connection pad whose other end extends through said other island-shaped insulating base material and projects to the outside. 3. The method according to claim 1 or 2, wherein the melting temperature of the connecting solder bumps of the intermediate terminal for connecting circuit components is higher than the melting temperature of solder bumps formed on circuit components such as ICs. A circuit wiring board equipped with intermediate terminals for connecting circuit components. 4. Connecting the circuit component and the circuit wiring board such that the electrode of the circuit component such as an IC and the circuit wiring pattern of the circuit wiring board placed opposite to the electrode are electrically connected. A circuit component mounting intermediate having a circuit component connecting intermediate terminal formed to electrically connect the first surface and the second surface of the insulating base material. After manufacturing a board and mounting at least one stage of the circuit component mounting intermediate board on the circuit wiring board, the circuit component mounting intermediate board is irradiated with an excimer laser beam. A method for manufacturing a circuit wiring board having intermediate terminals for connecting circuit components, characterized in that a portion of the insulating base material between the intermediate terminals for connecting circuit components formed on the intermediate substrate is removed.