JPH077811B2 - Semiconductor mounting board - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a package substrate such as a pin grid array and a hybrid IC substrate as a semiconductor mounting substrate that requires high-density mounting.

(Prior Art) In a semiconductor mounting substrate, a semiconductor element is mounted and fixed on the mounting portion, and this semiconductor element and a conductor circuit formed on the substrate are electrically connected using a bonding wire or the like. And is used as a semiconductor device. By the way, the semiconductor element mounted on this substrate, the conductor circuit and the bonding wire formed on the substrate are very susceptible to external impacts, moisture in the air, etc. The bonding wire must be protected by various methods.

Such protection of semiconductor elements and the like is usually performed as follows. That is, the sealing resin is dropped onto a portion requiring protection (usually in the vicinity of the semiconductor element) or a portion requiring protection is covered with a metal cap. In particular, in the case of covering with a metal cap, the semiconductor mounting substrate and the metal cap are joined via an adhesive layer. The metal cap used in this case is made of a material such as copper alloy or aluminum, and in order to ensure the corrosion resistance of the cap and the insulation with the substrate, the surface of the metal cap is oxidized. A film or resin film is formed.

Conventionally, a sealing structure using a metal cap is as shown in FIG. That is, in the conventional outer shape processing of the semiconductor mounting substrate, the plating lead wire end (23) remains on the outer peripheral edge (29) of the semiconductor element mounting surface side in an exposed state on the outer periphery of the board. . This is necessary for forming the conductor circuit (24) of the semiconductor mounting board, and as shown in the board plan view shown in FIG. 2 and the board sectional view shown in FIG. This is because the lead wire for plating is also cut at the same time as the final outer shape processing.

When the semiconductor mounting substrate has a sealing structure using a metal cap and the clearance between the outer shape of the substrate and the inner wall of the metal cap is small, the plating lead wire and the metal cap on the substrate are The inner wall of the semiconductor device may come into contact with the inner wall of the semiconductor device to cause an electrical short circuit or to easily cause discharge breakdown, which may stop the function of the semiconductor device. However, it is very difficult to increase the clearance between the outer shape of the substrate and the inner wall of the metal cap because this type of semiconductor mounting substrate is small.

(Problems to be Solved by the Invention) The present invention has been made in view of the above circumstances. The problem to be solved is that the end of a plated lead wire on the outer circumference of a substrate on which a conductor circuit is formed is formed. The part is exposed at the outer peripheral edge.

The object of the present invention is, as shown in FIGS. 1 to 3, to positively set a substrate portion including a lead wire for plating, which is a part of a conductor circuit formed on a semiconductor mounting substrate. By cutting the lead wire for plating, which is a part of the conductor circuit, to electrically connect the end portion of the lead wire for plating remaining on the outer peripheral edge of the semiconductor mounting board to the conductor circuit connected to the semiconductor element. The purpose of the present invention is to provide a semiconductor mounting substrate capable of completely preventing an electrical short circuit or the like that deteriorates the function of the semiconductor device by electrically insulating the substrate.

(Means for Solving the Problems) In order to solve the above problems, the means adopted by the present invention is that “a semiconductor element mounted on a substrate is sealed by a metal cap fitted to the outer periphery of the substrate. In the semiconductor mounting substrate, the substrate portion including a part of the conductor circuit formed on the semiconductor mounting substrate is deleted in the vicinity of the end of the substrate where the metal cap of the semiconductor mounting substrate contacts. And a groove portion for partially cutting the conductor circuit is formed.

Hereinafter, this means will be described in detail according to a specific example shown in the drawings.

FIG. 1 is a perspective view showing an embodiment of a semiconductor mounting substrate (1) according to the present invention, which is generally called a pin grid array. This semiconductor mounting substrate (1) has a semiconductor mounting portion and a conductor circuit (4) formed on the upper surface of a substrate made of a resin material. The groove portion (10) is formed by performing groove processing. As a result, in this semiconductor mounting substrate (1), the lead wire for plating, which has been extended to the outer periphery of the substrate as shown in FIG. 2 and is necessary for forming a circuit, is cut near the end (3). The conductor circuit (4) does not reach the outer peripheral edge of the substrate.

The groove processing of the substrate (1) may be performed after the outer shape processing of the substrate (1), but as shown in the substrate plan view of FIG. 2 and the substrate sectional view of FIG. The printed wiring board, in which a large number of semiconductor mounting boards are arranged in a continuous pattern, is grooved in the vicinity of the outline of the semiconductor mounting board so that the plating lead wire and the groove portion of the board are formed. It is also possible to remove the portion to be (10) at the same time and then cut and separate each semiconductor mounting substrate (1).

4 and 5, a semiconductor element (5) is mounted on a semiconductor mounting substrate (1) according to the present invention, and a metal cap (2) is mounted on the substrate (1) to cover the semiconductor mounting substrate (5). ) Is shown in a vertical cross-section. This semiconductor mounting substrate (1) is a substrate made of a resin material on which a semiconductor mounting portion and a conductor circuit (4) for external output are formed. After the semiconductor element (5) is mounted after forming (10) and the conductor circuit (4) on the substrate (1) and the semiconductor element (5) are connected by a bonding wire (6), a metal cap (2) is formed. The structure is sealed by.

(Operation of the Invention) By forming the groove (10) in the vicinity of the outer periphery of the substrate (1), the plating lead wire end (3) extending to the outer periphery and the conductor circuit (on the substrate (1) ( 4) can be electrically insulated from each other, and there is no problem even if the end portion (3) of the lead wire for plating and the inner wall of the metal cap (2) come into contact with each other. Conductor circuit (4)
Is covered with an adhesive layer (7) with the metal cap (2) to further improve the insulating property from the metal cap (2).

Next, the present invention will be described in detail based on the embodiments shown in the drawings.

(Example) Example 1 As shown in FIGS. 2 and 3, a semiconductor mounting portion and a conductor circuit (4) were continuously formed on a glass-epoxy substrate and cut along a cutting line (l). And then the substrate as a single piece (1)
To form. A plastic pin grid array substrate (1) provided with conductor pins (8) as external input / output terminals as shown in FIG. 4 is formed on the substrate (1) as a single piece. Groove processing was performed near the end of the outer shape to form a groove portion (10). After mounting and mounting a semiconductor element on the semiconductor mounting portion of the substrate (1), a metal cap (2) of the type enclosing the outer peripheral edge portion (9) of the substrate (1) from the outside.
It was sealed by. In this case, the plating lead wire end portion (3) exposed at the outer peripheral end portion of the substrate (1) is cut from the conductor circuit (4) by the groove portion (10) to form the adhesive layer (7). The conductor circuit (4) is coated so that the electrical insulation between the metal cap (2) and the conductor circuit (4) is improved.

Embodiment 2 As shown in FIG. 5, a plastic pin grid array substrate (1) in which a semiconductor mounting portion and a conductor circuit (4) are formed of a glass-epoxy substrate and conductor pins (8) are provided as external input / output terminals. 2) was formed, and a groove portion (10) was formed by subjecting the substrate (1) to groove processing in the vicinity of the outer end portion thereof. After mounting and mounting the semiconductor element on the semiconductor mounting portion of the substrate (1), only the semiconductor element mounting surface side was sealed with the metal cap (2). In this case, the plating lead wire end portion (3) exposed at the outer peripheral edge portion of the substrate is cut from the conductor circuit (4) by the groove portion (10), and the conductor circuit (4) is formed by an adhesive layer.
Was coated to improve the electrical reliability of the conductor circuit.

According to the present invention, the semiconductor element (5) is mounted on the substrate (1) on which the conductor circuit (4) is formed, and the semiconductor element (5) is connected by the bonding wire (6) or the like. In the semiconductor mounting substrate (1), even when the metal cap (2) is joined for the purpose of protecting the semiconductor element, the lead wire end portion (3) for plating on the outer circumference of the substrate (1) and the conductor circuit Even if (4) and (4) are cut by the groove (10) and the plating lead wire end (3) and the metal cap (2) come into contact with each other, there is no problem in the conductor circuit (4). The substrate (1) and the metal cap (2)
It is completely insulated by the adhesive layer (7) formed on the joint surface of the.

As a result, it is possible to provide a semiconductor mounting substrate that can completely prevent an electrical short circuit or the like that deteriorates the function of the semiconductor device mounting the semiconductor element.

[Brief description of drawings]

FIG. 1 is a perspective view of a semiconductor mounting substrate according to the present invention, and FIG.
FIG. 3 is a partial plan view showing a state in which the semiconductor mounting substrate is formed, FIG. 3 is a vertical sectional view taken along line III-III in FIG. 2, and FIG. 4 is a semiconductor shown in FIG. An enlarged vertical sectional view of a semiconductor device in which a mounting substrate is covered with a metal cap, FIG. 5 is an enlarged vertical sectional view of another type of semiconductor device, and FIG. 6 is a semiconductor in which a conventional semiconductor mounting substrate is covered with a metal cap. It is an expanded longitudinal cross-sectional view of an apparatus. Explanation of symbols 1 …… Semiconductor mounting board, 2 …… Metal cap, 3 ……
Lead wire end for plating, 4 ... Conductor circuit, 5 ... Semiconductor element, 6 ... Bonding wire, 7 ... Adhesive layer, 8
…… Conductor pin, 10 …… Groove.

Claims (1)

[Claims] 1. A semiconductor mounting substrate in which a semiconductor element mounted on the substrate is sealed by a metal cap fitted to the outer periphery of the substrate, wherein a substrate end portion of the semiconductor mounting substrate, which is in contact with the metal cap. A semiconductor mounting substrate, which is formed in the vicinity of the semiconductor mounting substrate and includes a groove portion for partially cutting the conductor circuit by removing a substrate portion including a part of the conductor circuit. .