JPH073643Y2 - Positioning device for semiconductor substrate - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a positioning device for use in a semiconductor lead bending process using a ceramic substrate.

[Conventional technology]

In manufacturing a semiconductor device using a ceramic substrate, first, a lead frame is attached and fixed on a ceramic semiconductor substrate, and external connection leads of the lead frame are bent into a predetermined shape. Then, after die bonding and wire bonding are performed, it is sealed with a ceramic cover.

In this manufacturing, the bending of the external leads of the leads integrated with the semiconductor substrate is performed using a lead molding die. Then, the semiconductor substrate and the lead frame are relatively positioned so that the leads are properly bent with respect to the semiconductor substrate.

This positioning is performed by the lead frame A as shown in FIG.
For example, the pilot holes P formed at the four corners are used and the pins of the mold are fitted into the pilot holes P. The lead frame A is attached and fixed to a ceramic semiconductor substrate B with molten glass or the like, positioned in the mold using the pilot hole P, and then the external lead a protruding from the semiconductor substrate b is bent and simultaneously piloted. The periphery including the hole P is cut to obtain a product.

[Problems to be solved by the device]

However, when the lead frame A is integrated with the semiconductor substrate B, if the manufacturing accuracy is insufficient, the centers of the lead frames A may be displaced as shown in FIG. 7A. That is, with respect to the center line L of the semiconductor substrate B, the lead frame A
The center line 1 of is shifted to the left, and so on. When the semiconductor substrate B and the lead frame A are displaced as described above, the pilot hole P is opened at a fixed position of the lead frame A, so that the relative position to the mold does not change, but the position of the semiconductor substrate B is displaced. Will end up. Thus, if the lead frame A and the semiconductor substrate B are in the correct positional relationship with each other,
Although the semiconductor substrate B is held at an appropriate position with respect to the mold, the semiconductor substrate B is displaced with respect to the mold because the positional relationship between the two is displaced from the beginning. Therefore, when the external lead a is bent with a die, the lead frame A is biased with respect to the semiconductor substrate B as shown in FIG. 7B, and the bent portion is the semiconductor substrate B.
It is not uniform with respect to the outline of.

In this way, if the lead frame A and the semiconductor substrate B are integrated with each other with high accuracy, the bending of the external lead a based on the lead frame A using the pilot hole P of the lead frame A can be performed without any trouble. . However, if the lead frame A and the semiconductor substrate B are integrated with each other within a tolerance, the semiconductor substrate B will not be set at an appropriate position when positioning in the mold using the pilot hole P. Therefore, in addition to the problem of processing that the outer leads a cannot be smoothly bent, the appearance of the product becomes poor and the yield is reduced.

Therefore, an object of the present invention is to enable a bending process in which the position of the external lead with respect to the semiconductor substrate is proper even if the integration accuracy of the semiconductor substrate and the lead frame is insufficient.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, a semiconductor substrate positioning device of the present invention is a positioning device for a die device in which a ceramic semiconductor substrate is formed in a rectangular shape and external leads of a lead frame integrated with the semiconductor substrate are bent. A positioning block for directing a corner portion of the semiconductor substrate placed on the seat of the mold is provided on an upper mold located above the seat, and the positioning block is formed by an elastic member in the seat direction. It is characterized in that a constraining surface for constraining the corner portion of the semiconductor substrate and the adjacent two sides in the vicinity thereof is formed at the lower end portion of the positioning block which is biased, and the constraining surface is a tapered surface whose lower end side opens.

Further, four positioning blocks are provided on the upper die corresponding to the four corners of the semiconductor substrate, and these positioning blocks can independently move in the seating direction according to the biasing force of the elastic member. You can also

〔Example〕

Hereinafter, the features of the present invention will be specifically described with reference to the embodiments shown in the drawings.

FIG. 1 is a perspective view showing a main part of a positioning device of the present invention, and FIGS. 2 and 3 are sectional views showing a positioning situation.

As shown in FIG. 2, the semiconductor substrate B in which the lead frame A is integrated in advance is placed on the receiving seat 1 of the lead molding die device. The upper die 2 is arranged above the receiving seat 1 so as to be able to move up and down, and positioning blocks 3 for restraining the corners of the four corners of the semiconductor substrate B are provided at four places on the upper die 2. That is, since the semiconductor substrate B is generally a square or a rectangle, the semiconductor block B is positioned by the positioning block 3 by restraining a plurality of corners.

The upper end of the positioning block 3 is slidably accommodated in a chamber 2a provided in the upper mold 2, and the lower end projects from the bottom surface of the upper mold 2. A compression coil spring 2b for urging the positioning block 3 toward the seat 1 is provided in the chamber 2a.

In addition, the portion where the positioning block 3 restrains the corner portion of the semiconductor substrate B forms restraining surfaces 3a and 3b as shown in FIG. These constraining surfaces 3a and 3b are positioned so that they are orthogonal to each other when the plane cross section is cut.
It is formed by stealing meat from the surrounding wall to the inside. The constraining surfaces 3a and 3b are tapered so that the cross section of the opening widens as it goes downward.

The constraining surfaces 3a and 3b having such a shape contact the surfaces b-1 and b-2 of the semiconductor substrate B which are adjacent to each other at right angles and constrain the corner portions, as shown in the drawing. And the positioning block 3 positions with respect to a metal mold | die apparatus by restraining the four corners of the semiconductor substrate B, or the corner part on a diagonal. Also,
By making the constraining surfaces 3a and 3b tapered, one constraining surface 3a can exert a force to push the semiconductor substrate B in the arrow X direction and the other constraining surface 3b in the arrow Y direction in FIG. . This will be described with reference to FIG.

In FIG. 3, the semiconductor substrate B integrated with the lead frame A is set on the receiving seat 1 while deviating to the right from the proper position. When the upper mold 2 is lowered during this setting, the positioning block 3 located on the right side in the drawing hits the right end of the semiconductor substrate B, and the left positioning block 3 does not touch the left end of the semiconductor substrate B. Place on the pedestal 1. When the upper mold 2 is further lowered, the left and right positioning blocks 3 are compressed coil springs.
The contraction of 2b causes it to move into the chamber 2a. At this time, the restraining surface 3a of the positioning block 3 on the right side
Is tapered, and the contact surface with the semiconductor substrate B moves to the left as it descends. Therefore, when the upper mold 2 is lowered, the semiconductor substrate B is pushed and moved to the left as shown by the arrow in the figure, and comes into contact with the restraining surface 3a of the left positioning block 3 and stops.

It should be noted that although shown in the drawing as being two-dimensional in the left-right direction, it is needless to say that the four positioning blocks 3 provide a three-dimensional handling that combines movements in the X and Y directions shown in FIG. Is.

By shifting the semiconductor substrate B by the positioning block 3 described above, the semiconductor substrate B can be aligned with the processing core of the mold device, and the molded product can be set with the semiconductor substrate B as a reference.

FIG. 4 is a sectional view of an essential part for explaining the actual bending process of the outer lead a.

In FIG. 4 (a), the semiconductor substrate B with the lead frame A set on the seat 1 is positioned according to the working core of the mold device by the operation of the positioning portion 3 described in FIG. 3. After that, by punching with the punch 4, the unnecessary portion of the lead frame A, that is, the outer lead a is left and the periphery thereof is cut.

Next, as shown in FIG. 2B, the molding blocks 5a and 5b respectively arranged on the seat 1 and the upper mold 2 are raised and lowered, and the tips of the external leads a are bent into the upper mold. After retracting these molding blocks 5a, 5b, a curling molding block 6a is newly set on the receiving seat 1 side as shown in FIG. It is moved to the tip side of the external lead a by descending. The curling molding block 6a promotes the tips of the bent outer leads a and further curls in a U shape.

After curling, the bending blocks 7a and 7b provided on the seat 1 and the upper mold 2 are raised and lowered respectively as shown in FIG.
Is bent to the upper mold 2 side. Further, as shown in FIG. 2E, the molding block 8a on the side of the seat 1 is attached to the upper mold 2
Is moved to the external lead a side by the pressing cam 8b on the side,
The external lead a is bent to a posture that is substantially perpendicular to the semiconductor substrate B.

In addition, the above steps are continuously performed by using a dedicated mold device arranged on the manufacturing line, and the positioning block 3 is provided on the upper mold 2 of each mold device to properly align the machining core. You can

FIG. 5 is a sectional view of a product processed by using the positioning block 3 of the present invention when the lead frame A is biased to the left with respect to the semiconductor substrate B shown in FIG. 7 (a). Positioning with respect to the mold device is performed by aligning the semiconductor substrate B with the processing core of the mold device instead of using the conventional lead frame A as a reference, and therefore, with respect to the external lead a protruding from the periphery thereof. Also, the processing cores of the mold device are aligned. Therefore, the lead frame A with respect to the semiconductor substrate B is
Even if they are integrated by being displaced from each other, the bending process of the left and right external leads a with respect to the semiconductor substrate B becomes symmetrical, and the appearance of the product is not damaged.

[Effect of device]

As described above, in the positioning device of the present invention, positioning is performed with the semiconductor substrate as a reference by the positioning block that restrains the corner portion of the semiconductor substrate. Therefore, even if the semiconductor substrate and the lead frame are not properly integrated with each other, the semiconductor substrate can be aligned with the processing core, and the bending of the external lead can be processed without deviation from the semiconductor substrate. Therefore, compared to the conventional positioning using the pilot hole as a reference for the lead frame, the bending of the external lead and the product shape after processing are improved, and the productivity is reduced without lowering the yield. It is possible to improve.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of a positioning device of the present invention, FIGS. 2 and 3 are sectional views showing a positioning state of a semiconductor substrate by a positioning block, and FIG. 4 is a view showing positioning of a semiconductor substrate to external leads. FIG. 5 is a front view showing a product shape after processing, FIG. 6 is a plan view showing a lead frame having pilot holes, and FIG. 7 (a) shows a semiconductor substrate. FIG. 7 (b) is a plan view showing the deviation from the lead frame and shows a bending defect of the external lead. 1: seat, 2: upper mold 2a: chamber 2b: compression coil spring 3: positioning block, 3a, 3b: constraining surface 4: punch, 5a, 5b: forming block 6a: curling forming block 6b: pressing cam 7a, 7b : Bending forming block 8a: Forming block, 8b: Rolling down cam

Claims (2)

[Scope of utility model registration request] 1. A ceramic semiconductor substrate having a rectangular shape,
A positioning device for a die device for bending an outer lead of a lead frame integrated with the semiconductor substrate, wherein the positioning block oriented to a corner portion of the semiconductor substrate placed on a seat of the die is received by the receiving block. The positioning block is provided on an upper mold located above the seat, and the positioning block is biased by an elastic member in the seating direction. Further, the lower end of the positioning block constrains the corner portion of the semiconductor substrate and the adjacent two sides in the vicinity thereof. A semiconductor substrate positioning device, wherein a constraining surface is formed, and the constraining surface is a tapered surface whose lower end is opened. 2. Positioning blocks are provided on the upper die in correspondence with the four corners of the semiconductor substrate, and four of these positioning blocks independently advance and retreat in the seating direction according to the biasing force of the elastic member. Claim 1 characterized in that it is possible.
A semiconductor substrate positioning device as described above.