JP2000012587A - Electric characteristic inspection and coining method of solder bumps of circuit board for semiconductor chip mounting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable simultaneously electric characteristic inspection of solder bumps and flat press work of the solder bumps which adjusts the heights of top parts of the solder bumps without giving trouble. SOLUTION: In this electric characteristic inspection and coining method, solder bumps 30 are heated at a low temperature and softened, and a planar tip of a tester needle 60 is pressed against top parts of the solder bumps 30 with a specified pressing force. By using the tester needle 60, electric insulation or electric conduction of the solder bumps 30 is inspected. The above softened top parts of the solder bumps 30 are flatly pressed with the planar tip of the tester needle 60, and the heights of the top parts of the solder bumps 30 from the surface of a circuit board body 10 are adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting electrical characteristics and coining (flat pressing) of solder bumps formed on pads formed on a surface of a circuit board for mounting a semiconductor chip on which a semiconductor chip is surface-mounted by a flip chip bonding method. ) Method.

[0002]

2. Description of the Related Art As a circuit board for mounting a semiconductor chip, a circuit board in which a circuit board body 10 as shown in FIGS. 3 and 4 is formed of a resin, or a circuit board as shown in FIGS. A circuit board in which the board body 10 is formed of ceramic is known. In this circuit board, a disc-shaped pad 20 that is electrically connected to an electrode of a semiconductor chip is formed on the surface of the circuit board body 10. In the circuit board shown in FIGS. 3 and 4, the pad 20 is formed by etching a copper foil adhered to the surface of the circuit board body 10. On the other hand, in the circuit board 10 shown in FIGS. 5 and 6, the pads 20 are formed on the surface of the circuit board body 10 using metallization.

In the circuit board shown in FIGS. 3 and 4, the pad 20 is connected to an end of a wiring circuit 40 formed by etching a copper foil adhered to the surface of the circuit board body 10. It is formed. On the other hand, in the circuit board shown in FIGS. 5 and 6, the circuit board is formed so as to be continuous with the upper end of a metallized columnar conductive via 50 penetrating vertically above and below the circuit board body 10.

On the pad 20, a solder bump 30 having a substantially hemispherical shape is formed. Then, the Au formed on the electrode of the semiconductor chip is placed on the top of the solder bump 30.
Bumps such as bumps and solder bumps can be connected by soldering.

In this circuit board, the pad 2
0, an electrical property test for testing the electrical insulation or electrical continuity of the solder bump 30 with respect to the wiring circuit 40 or the conductor via 50 or the like is performed. The electrical characteristic inspection of the solder bump 30 is performed by SOT (short open test).
Called. Then, the quality of the circuit board on which the semiconductor chip is surface-mounted is selected.

In the inspection of the electrical characteristics of the solder bump 30, conventionally, as shown in FIG. 7, a sharply pointed conical tip of a tester needle 60 made of a conductor such as a metal is attached to the top of the solder bump 30. The pressing force is about 20 g. Then, using the tester needle 60, the electrical insulation or electrical conductivity of the solder bump 30 pressed against the tester needle 60 is inspected by a tester (not shown).

[0007]

Since the solder bumps 30 are low in hardness and soft, the tip of the solder bumps 30 is sharply pointed in a conical shape of the tester needle 60 as described above. When the tip was pressed, the top of the soft solder bump 30 was damaged by the tip of the tester needle 60 as shown by the broken line in FIG.
Then, an arc-shaped or the like scratch left on the top of the solder bump 30. As a result, under the influence of the scratch, the bump formed on the electrode of the semiconductor chip may not be reliably soldered and connected to the top of the damaged solder bump 30 by applying a pressure equal to or greater than a predetermined pressing force. Was.

In addition, when the above-mentioned circuit board for mounting a semiconductor chip is manufactured, the solder bumps 30 are heated to about 100 ° C.
Then, the solder bumps 30 are softened by heating at a low temperature, and the tops of the solder bumps 30 are pressed (coined) using a punch or the like. Then, the circuit board body 10 on the top of the solder bump 30
The height from the surface is adjusted. This solder bump 30
The reason for flat pressing the top part is that the semiconductor chip 70 is surface-mounted on the circuit board by the flip-chip bonding method, as shown in FIGS. If the height of the top of the solder bump 30 formed on each of the pads 20 varies,
A pressure equal to or higher than a predetermined pressing force is applied to the top of each of the plurality of solder bumps 30 by a flip chip bonding method by applying a bump 80 formed on each of a plurality of electrodes formed side by side on one surface of the semiconductor chip 70 corresponding thereto. This is because soldering connection cannot be made uniformly and reliably.

Conventionally, the work of flattening the top of the solder bump 30 is performed separately from the above-described inspection of the electrical characteristics of the solder bump 30, and the manufacture of the circuit board for mounting a semiconductor chip is troublesome and troublesome. I was supposed to.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a solder bump for pressing the tip of a tester needle against the top of a solder bump to check the electrical insulation or electrical conductivity of the solder bump. Of the solder bumps without damaging the tops of the solder bumps, and at the same time, easily perform the flattening work of the solder bumps to adjust the height of the tops of the solder bumps without trouble. It is an object of the present invention to provide a method for inspecting and coining electrical characteristics of solder bumps on a circuit board for mounting a semiconductor chip and a method for coining (electrical characteristic inspection and coining method).

[0011]

In order to achieve the above object, an electric characteristic inspection and coining method according to the present invention provides a method for inspecting a plurality of pads formed side by side on a surface of a circuit board body.
The method is performed on a circuit board for mounting a semiconductor chip on which solder bumps electrically connected to electrodes of the semiconductor chip are formed, and includes the following steps. a. Heating the solder bumps at a low temperature to soften the solder bumps; b. The flattened tip of a tester needle is pressed against the top of the softened solder bump with a predetermined pressing force, and the electrical insulation or electrical conductivity of the solder bump is inspected using the tester needle. And flattening the top of the softened solder bump with the flat tip of the tester needle to adjust the height of the top of the solder bump from the surface of the circuit board body.

In this electrical characteristic inspection and coining method, after the solder bump is heated at a low temperature to soften it, a tester needle having a flat tip is pressed against the top of the solder bump with a predetermined pressing force, and the tester is tested. The top of the solder bump is flattened with the flat tip of the needle, and the height of the top of the solder bump can be adjusted. At the same time, using a tester needle pressed against the top of the solder bump, the tester can inspect the electrical insulation or electrical continuity of the solder bump. The inspection of the electrical properties of the solder bump pressed against the tester needle and the flat pressing of the top of the solder bump can be performed simultaneously without any trouble.

At this time, the flat tip of the tester needle is pressed against the top of the solder bump, so that the tip of the tester needle does not damage the top of the soft solder bump in an arc shape or the like. be able to.

In the electrical characteristics inspection and coining method according to the present invention, a plurality of the tester needles are erected and provided side by side, and the planar tips of the plurality of tester needles are attached to the corresponding circuit board body. Simultaneously pressed with a predetermined pressing force on the top of the softened solder bump formed on each of the pads formed side by side on the surface of the plurality of pads, and using the plurality of tester needles, the plurality of solder bumps Along with inspecting the electrical insulation or electrical continuity of the plurality of tester needles, the flattened tips of the plurality of tester needles simultaneously flatten the tops of the plurality of softened solder bumps, and the plurality of Preferably, the height of the top of each solder bump from the surface of the circuit board body is adjusted.

[0015] In this electrical characteristic inspection and coining method, the plurality of tester needles provided upright and arranged side by side are provided with a plurality of tester needles. Can be simultaneously pressed with a predetermined pressing force to the top of the softened solder bump formed on each pad. Then, by using the plurality of tester needles, the electrical insulation or electrical conductivity of the solder bumps formed on the plurality of pads can be inspected at a time without trouble. At the same time, the flattened tips of the plurality of tester needles simultaneously push the tops of the plurality of softened solder bumps flat, and multiply the height of the tops of the plurality of solder bumps by a trouble. Can be prepared at once without using

In the electrical characteristics inspection and coining method according to the present invention, the flattened tips of the tester needles are softened on a plurality of pads formed on a surface of the circuit board body. With a predetermined pressing force one after another, using the tester needle,
The electrical insulation or electrical continuity of each of the plurality of solder bumps is inspected one after another, and the tops of the plurality of softened solder bumps are successively flattened with the flat tip of the tester needle. Preferably, the height of the top of each of the plurality of solder bumps from the surface of the circuit board body is adjusted one after another.

In the electrical characteristics inspection method and coining method, the flat tip of the tester needle is connected to the softened solder bump formed on each of a plurality of pads formed side by side on the surface of the circuit board body. It can be pressed against the top one after another with a predetermined pressing force. Then, by using the tester needle, the electrical insulation or the electrical conductivity of the solder bumps formed on the plurality of pads can be inspected one by one without error by the tester. At the same time, the tops of the softened solder bumps formed on the plurality of pads can be reliably and flatly pushed one after another one by one with the planar tip of the tester needle. The height of the top of each of the plurality of solder bumps can be adjusted one by one without error.

[0018]

Next, embodiments of the present invention will be described with reference to the drawings. FIGS. 1 and 2 show a preferred embodiment of the electrical characteristics inspection and coining method of the present invention, and FIGS. 1 and 2 are explanatory diagrams of the steps. Hereinafter, the electrical characteristic inspection and coining method will be described.

In the electrical characteristic inspection and coining method shown in the figure, the solder bump 30 is heated to about 100 ° C. at a low temperature to soften the solder bump 30. In this case, the solder bump 30 is replaced with the pad 20 on which the bump is formed.
It is placed in a furnace (not shown) together with the circuit board main body 10 on which the pads are formed, and is heated at a low temperature.

Next, as shown in FIG. 1, the flat tip of the tester needle 60 is pressed against the top of the softened solder bump 30 with a pressing force of about 40 to 50 g. I have. Then, using the tester needle 60, the electrical insulation or electrical conductivity of the solder bump 30 is inspected by a tester (not shown).

At the same time, about 40 to 50 g of the top of the softened solder bump 30 is flattened (coined) with a flat tip of the tester needle 60 with a pressing force of about 40 to 50 g. Then, as shown in FIG.
The height h from the surface of the circuit board body 10 at the top of 0 is adjusted to a constant value.

The electric characteristic inspection and coining method shown in FIGS. 1 and 2 comprises the above steps. In this electric characteristic inspection and coining method, the electric characteristic inspection of the solder bump 30 to which the tester needle 60 is pressed and its The flat pressing operation of the top of the solder bump 30 can be performed simultaneously without any trouble.

At this time, the flat tip of the tester needle 60 is pressed against the top of the solder bump 30, and the tip of the tester needle 60 is softened by the tip of the tester needle 60 so that a circle is formed on the top of the solder bump 30. It is possible to prevent arcuate scratches and the like. In addition, it is possible to prevent the bump formed on the electrode of the semiconductor chip from being unable to be properly soldered and connected to the top of the solder bump 30.

In this electrical characteristic inspection and coining method, as shown in FIG. 1, a plurality of tester needles 60 are provided standing up and arranged, and the plurality of tester needles 6 are provided.
0 may be simultaneously pressed with a predetermined pressing force onto the tops of the softened solder bumps 30 formed on a plurality of pads 20 formed side by side on the surface of the circuit board body 10 corresponding thereto. good. Multiple tester needles 6
0 may be held in an upright state in a grid or the like by using a jig (not shown) made of an insulator. Then, using the plurality of tester needles 60, the electrical insulation or electrical conductivity of the plurality of solder bumps 30 may be inspected. Then, the electrical property inspection of the solder bumps 60 formed on the plurality of pads 20 formed on the surface of the circuit board body 10 may be performed at once without any trouble.

At the same time, the tops of the plurality of softened solder bumps 30 are simultaneously pushed flat by the planar tips of the plurality of tester needles 60, and the tops of the plurality of solder bumps 30 are pressed. The height h from the surface of the circuit board body 10 may be adjusted at a time without trouble.

Alternatively, the flat tip of the tester needle 60 is pressed with a predetermined pressing force onto the top of the softened solder bump 30 formed on each of the plurality of pads 20 formed on the surface of the circuit board body 10. You may press one after another.
Then, using the tester needle 60, the electrical insulation or electrical conductivity of each of the plurality of solder bumps 30 may be inspected one after another. Then, the electrical characteristic inspection of the plurality of solder bumps 30 may be performed one by one without error.

At the same time, the tops of the plurality of softened solder bumps 30 are successively flattened with the flat tip of the tester needle 60, and the circuit board body at the top of each of the plurality of solder bumps 30 is pressed. The heights h from the surface of the ten may be adjusted one by one without error.

[0028]

As described above, according to the electrical characteristic inspection and coining method of the present invention, the flat surface of the tester needle is placed on the top of the softened solder bump formed on the pad formed on the surface of the circuit board body. The tip of the solder bump is pressed, and the tester needle is used to test the electrical insulation or electrical continuity called SOT of the solder bump, and the top of the softened solder bump is placed on the flat surface of the tester needle. The height h of the top of the solder bump from the surface of the circuit board main body can be adjusted to a constant value by flat-pressing with the tip of the solder bump. In addition, the inspection of the electrical properties of the solder bumps and the flattening (coining) work can be performed simultaneously without trouble.

In this case, it is possible to prevent the top of the soft solder bump from being damaged by the tip of the tester needle pressed against it. And under the influence of the wound,
The bump formed on the electrode of the semiconductor chip on the top of the solder bump can be prevented from being accurately soldered and connected.

[Brief description of the drawings]

FIG. 1 is a process explanatory view of an electrical characteristic inspection and coining method of the present invention.

FIG. 2 is an explanatory diagram showing steps of an electrical characteristic inspection and coining method according to the present invention.

FIG. 3 is a partially enlarged plan view of a circuit board.

FIG. 4 is a partially enlarged front view of a circuit board.

FIG. 5 is a partially enlarged plan view of a circuit board.

FIG. 6 is a partially enlarged front sectional view of a circuit board.

FIG. 7 is a process explanatory view of a conventional electrical characteristic inspection method.

FIG. 8 is an explanatory view showing a method of surface mounting a semiconductor chip on a circuit board by a flip chip bonding method.

FIG. 9 is an explanatory view showing a method of surface mounting a semiconductor chip on a circuit board by a flip chip bonding method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Circuit board main body 20 Pad 30 Solder bump 40 Wiring circuit 50 Conductor via 60 Tester needle 70 Semiconductor chip 80 Bump formed on electrode of semiconductor chip

Claims (3)

[Claims] 1. A semiconductor chip mounting circuit board comprising a plurality of pads formed side by side on a surface of a circuit board body and having solder bumps electrically connected to electrodes of the semiconductor chip formed thereon. A method for inspecting and coining electrical characteristics of solder bumps on a circuit board for mounting a semiconductor chip, comprising the steps of: a. Heating the solder bumps at a low temperature to soften the solder bumps; b. The flattened tip of a tester needle is pressed against the top of the softened solder bump with a predetermined pressing force, and the electrical insulation or electrical conductivity of the solder bump is inspected using the tester needle. And flattening the top of the softened solder bump with the flat tip of the tester needle to adjust the height of the top of the solder bump from the surface of the circuit board body. 2. A plurality of tester needles are provided standing up and arranged side by side, and a plurality of tester needles each having a planar tip are arranged on a surface of the circuit board body corresponding to the plurality of tester needles. Simultaneously press against the top of the softened solder bump formed on the pad with a predetermined pressing force, using the plurality of tester needles, electrically insulating or electrically conducting the plurality of solder bumps. And simultaneously pressing the tops of the plurality of softened solder bumps with the planar tips of the plurality of tester needles at the same time, and the circuit board body at the top of each of the plurality of solder bumps 2. The method for inspecting and coining electrical characteristics of solder bumps of a circuit board for mounting a semiconductor chip according to claim 1, wherein the height from the surface of the semiconductor chip is adjusted. 3. A flat tip of the tester needle,
Each of the plurality of solders is pressed against the top of the softened solder bump formed on each of the pads formed side by side on the surface of the circuit board body with a predetermined pressing force, and the tester needle is used. Inspect the electrical insulation or electrical continuity of the bumps one after another, and press the tops of the plurality of softened solder bumps one after another with the flat tip of the tester needle, and press each of the plurality of solder bumps. 2. The method according to claim 1, wherein the height of the top of the solder bump from the surface of the circuit board body is adjusted one after another.