JPH03109746A - Resin sealing of semiconductor element and resin sealing mold - Google Patents

Abstract

PURPOSE:To prevent frame bending and gate remainder from occurring and improve the quality of a semiconductor which is formed in the frame by providing a pair of upper and lower groove ejector pins which pushes up a groove part in a region where there are no electrode materials and by separating the semiconductor element from a gate within a mold automatically. CONSTITUTION:A mold has a pair of upper and lower body ejector pins 3 and 5 which push up a semiconductor element part and a pair of upper and lower groove ejector pins 4 and 6 which push up a groove part in a region where there are no electrode materials. After the forming is completed, when the mold is separated by a small distance, a pair of body ejector pins 3 and 5 keep pressing the semiconductor part to the other mold and a pair of groove ejector pins 4 and 6 keep pressing the groove part to the other mold so that the semiconductor part and the groove part are separated and the molding process advances in the order of forming, groove separation, and mold release by a double operation of mold release by means of the groove ejector pins 4 and 6 and the body ejector pins 3 and 5, thus preventing frame bending and gate remainder from occurring and improving the quality of the semiconductor element.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a transfer molding mold that allows cutting of a semiconductor element portion and a gate portion within a resin-sealed mold.

(Prior art) Fig. 2 is a general plan view showing a resin-sealed object immediately after resin sealing, and Fig. 3 is a sectional view of a conventional mold. The semiconductor element 23 is not scaled to scale.

FIG. 2 shows a general structure of a resin-sealed electronic part, in which a semiconductor chip 23a is connected to a lead frame (also referred to as a frame) 26 and electrodes of lead wires 26, immediately after sealing.

23 is a semiconductor element in which the semiconductor chip 23a is sealed; 26
24a is a lead frame, and 24a is a gate that fills the semiconductor element with resin from the runner 24.

Conventionally, there is a mold shown in FIG. 3 as a mold for resin-sealing this type of semiconductor element.

In the figure, 1 and 2 are cavity blocks, and the cavity blocks 1 and 2 have cavities 10,
One cavity block 1 is provided with a groove 9 for a runner 24 and a gate 24a. In order to inject the resin into the cavity IO, the bot 28, the runner 24, the gate 24
Resin is sequentially injected into the cavities 10 in the order of a.

Since the cavity block is still heated even after filling is completed, the semiconductor element is molded only after the molten resin is cured by this heat.

After molding is completed, the operation of the mold press (not shown) causes
The upper and lower molds are opened. At this time, the ejector plate 37 which was restrained by the lifter bin 43 due to the force of the spring 41
is pushed out downward, and the semiconductor element 23 and the runner 24 are simultaneously ejected from the cavity 10 by the main body ejector pin 33 fixed to the ejector plate 37 and the groove ejector plate 34, and are left on the cavity block 2 of the lower mold. When the lower mold further descends, the ejector plate 38, which was biased by the spring 42 and positioned by the stopper bolt 44, hits the fixed rod 25, and the main body ejector pin 35 and groove ejector pin 36 fixed to the ejector plate 38 protrude from the cavity. The semiconductor element 2 with the runner 24 attached thereto
3 is released from the mold.

Thereafter, the released semiconductor element 23 with the gate 24 is taken out from the mold, and the gate 24 is separated.

[Problem to be solved by the invention]

However, in such a conventional mold for resin-sealing a semiconductor element, the gate 24a is in close contact with the lead frame 26, so if it is removed from the mold and left to stand, the lead frame will shrink due to the resin shrinking. bending occurs, which has a significant impact on subsequent processes. Furthermore, if the separation method is incorrect because the frame and gate are in close contact with each other, the gate will remain on the frame, resulting in an additional step of removing it in a later process. Therefore, the workability is poor, the working time is long, and it is uneconomical.

An object of the present invention is to separate a gate from a resin-sealed semiconductor element without using a knife or the like inside a mold.

[Means to solve the problem]

In the resin sealing method of invention 1, a cavity for a semiconductor element connected to an electrode material is provided on a separation surface between an upper mold and a lower mold, and a cavity is provided in one of the upper mold or the lower mold continuous with this cavity. In a resin encapsulation method for a semiconductor element using a mold in which a groove formed with a gate and a runner is formed, the mold has a pair of upper and lower body ejector pins that protrude the semiconductor element portion, and a groove formed in an area where the electrode material is not present. and a pair of upper and lower groove ejector pins that protrude the part, and after injecting resin and completing molding, the pair of main body ejector pins press the semiconductor part against the other mold, and the pair of groove ejector pins press the semiconductor part against the other mold. The mold is separated by a minute distance while being held in one of the molds, and the semiconductor portion and the groove portion are separated while remaining in each mold, and then the mold is completely separated. At the same time, the other body ejector pin and the one groove ejector pin are projected and released from the mold.

The resin-sealed mold of invention 2 has a cavity for a semiconductor element connected to an electrode material on the separation surface between the upper mold and the lower mold, and a cavity continuous to this cavity provided in one of the upper mold or the lower mold. A mold is formed by forming a groove consisting of a gate and a runner, and the mold has a pair of upper and lower body ejector pins that protrude the semiconductor element portion, and a pair of upper and lower body ejector pins that protrude the groove portion in an area where the electrode material is not present. a groove ejector pin, one of the main body ejector pins and one of the lipor pins are fixed to a first ejector plate provided on the one mold and biased toward the separating surface by a first spring, When the tip of the lipor pin matches the separation surface, the tip of the one main body ejector pin is in a position where resin molding is possible, and the tip is placed on the separation surface side with a gap between the first ejector plate and the anti-separation surface. a second spring biased by a second spring in the direction
One of the grooved ejector pins is fixed to the ejector plate of the invention, and one stopper bolt is provided, and when the second ejector pin plate is biased by the second spring and stops at the one of the bolts, The tip of the one groove ejector pin is in a position where it can be molded with resin, the second spring is weaker than the first spring, is provided on the other mold, and is biased in the direction of the separation surface by a third spring. the other of the grooved ejector pins and the other lipor pin are fixed to a third ejector plate that is attached to the groove, and when the tip of the other lipor pin matches the separation surface, the tip of the other grooved ejector pin can be molded with resin. The main body ejector pin is placed in a position such that a fourth ejector plate is disposed on the side opposite to the bone separation surface with a gap between the third ejector plate and is biased by a fourth spring in the direction opposite to the separation surface. The other is fixed, and the other stopper bolt is provided, and when the fourth ejector plate is urged by the fourth spring and stopped by the other stopper bolt, the tip of the other main body ejector pin can be molded with resin. position, and the fourth
The other mold is provided with an ejector rod that pushes out the fourth ejector plate against a spring.

[Effect]

In invention 1, when the molds are separated by a minute distance after molding is completed, the pair of main body ejector pins keep the semiconductor part pressed by the other mold, and the pair of groove ejector pins keep the groove part pressed by one mold. Therefore, the semiconductor part and the groove part are separated, and then the groove ejector pin and the main body ejector pin release each of them from the mold, which is a double operation, and the mold progresses in the order of molding, groove separation, and mold release. .

Invention 2 is a mold for carrying out the method related to the process of Invention 1, and the molded semiconductor element 23 part has a structure that can be ejected by the zero-body jetter pins 3 and 5, and the gate 24a and the runner 24 are Groove ejector pins 4 and 6
It has a structure that can be ejected (state p+).

When the mold is slightly opened (state Pg), the relative movement of the four types of ejector pins with respect to the mold is such that the main body ejector pin 3 on one side and the groove ejector pin 6 on the other side move, and the gate 24a and the runner 24 move on one side. The groove ejector pin 4 on the other hand and the main body ejector pin 5 on the other hand remain fixed to their respective molds without movement. Such movement of each ejector pin is such that, for example, in one main body ejector pin 3, the first spring 11, one lipor pin 13, the first
The semiconductor element 23 ejected by one main body ejector pin 3 generated by the ejector plate 15 of the cavity 1
The runner 24 that was ejected from the groove ejector pin 6 remains on one mold.

In this way, the semiconductor element 23 remains in the other mold, and the runner 24 remains in the other mold, so that the gate 248 part and the semiconductor element 23 remain in the other mold.
The connecting part (for example, height 0.4 m, width 4 cranes) will be separated, and the separation will be performed inside the mold.

When the mold is further opened (shape GP3 >, one mold has the first
The spring 11 presses the second ejector plate 7 through the first ejector plate 15 and pushes out the groove ejector pin 4 on one side to release the runner 24 with the gate 24a from the mold, while the ejector rod 25 on the other mold is the fourth ejector plate 1
The other main body ejector pin 5 is ejected through the ejector pin 6 to release the semiconductor element 23 from the mold.

〔Example〕

FIG. 1 is a process diagram showing a cross-sectional view of a mold according to an example.

Here, state P+ is a state where molding has been completed, state P! State P3 indicates a state in which the mold is placed at a very small distance, and state P3 indicates a state in which the mold is completely opened. A plan view of only the object to be sealed seen through the mold in state pI is shown in FIG. 2, but it is not to scale.

1 and 2 are the molding cavity 0 and the gate 24a1
a cavity block with grooves 9 for runners 24;
7 and 8 are a second ejector plate and a third ejector plate 15 having a gate 24a, a groove ejector pin 4 on one side and a groove ejector pin 6 on the other side for protruding the runner 24;
and 16 are a first ejector plate and a fourth ejector plate 13 having one body ejector pin 3 and the other body ejector pin 5 from which the semiconductor element 23 is protruded;
is one lipta pin that moves one main body ejector pin 3 to a moldable position during molding.

11 is a first spring for protruding one main body ejector pin 3, 1B is a stopper bolt for stopping one groove ejector pin 4 at a fixed position where it can be formed during molding, and is moved to a fixed position by a second spring 17. There is. Here, the force of the second spring 17 is made weaker than that of the first spring 11.

Reference numeral 19 designates the other lipor pin that moves the other groove ejector pin 6 to a fixed position where it can be molded during molding, and 20
is the third spring that pushes out the other groove ejector pin 6;
4 is the other stopper bolt that moves the other main body ejector pin 5 to a fixed position during molding, and the fourth spring 12
It is operating in a fixed position.

The ejector rod 25 is used to protrude the semiconductor element 23 from the cavity in the final step (state P3), and has the role of pushing up the fourth ejector pin plate 16. Condition P! is a state in which the molds are separated by a minute distance at the separation surface after molding, the first ejector plate 15 is lowered by the first spring 11, and the semiconductor element 23 portion is ejected by one main body ejector pin 3. It turns out.

However, if the gate 24a falls down together with the semiconductor element 23 during this operation, the gate cannot be separated. The groove ejector pin 6 is raised to prevent the gate 24a and runner 24 portions from falling, and the semiconductor element 23 portion and the gate 24a portion are separated.

In state P3, state P2 is further advanced, and the runner 24 with the gate 24a is ejected by one of the groove ejector pins 4 through the force of the first spring 11. At the same time, the semiconductor element 23 portion buried in the cavity block 2 by the ejector rod 25 is ejected by the other main body ejector pin 5 and released from the mold. Note that other electrode materials can be used instead of the lead frame 26 of the embodiment.

[Effects of the Invention] Since the resin sealing method and resin sealing mold for semiconductor elements according to this group of inventions are configured as described above,
It has the following effects.

Since the semiconductor element and the gate are automatically separated inside the mold, the frame bending and remaining gates that occur with conventional methods are eliminated, and the quality of the semiconductor element molded into the frame is improved, resulting in easier post-processing. Problems in the process will be improved. In addition, conventionally, the semiconductor element was removed from the mold and the gate was cut manually or by machine.
This step is eliminated, simplifying the production process and making it easier for one person to operate multiple mold presses.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing a cross-sectional view of the mold of the example, and FIG. 2 is a general plan view of the object to be sealed immediately after resin sealing. FIG. 3 is a sectional view of a conventional mold. 1.2... Cavity block, 3, 33... One main body ejector pin, 4, 34... Other groove ejector pin, 5.35... Other main body ejector pin,
6.36...Other groove ejector pin, 11...First spring, 12...Fourth spring, 13.19.43.
...Lifter pin, 14.18.44...Stopper bolt, 17...Second spring, 20...Third spring, 2
3...Semiconductor element, 24...Runner, 25...Ejector rod, 28...Pot. Figure Figure F8 Figure

Claims (1)

[Claims] 1) A cavity for a semiconductor element connected to an electrode material is provided on the separation surface between the upper mold and the lower mold, and a cavity is provided in one of the upper mold and the lower mold, continuous with this cavity. In a resin encapsulation method for a semiconductor element using a mold in which a groove formed with a gate and a runner is formed, the mold has a pair of upper and lower body ejector pins that protrude the semiconductor element portion, and a groove formed in an area where the electrode material is not present. and a pair of upper and lower groove ejector pins that protrude the part, and after injecting resin and completing molding, the pair of main body ejector pins press the semiconductor part against the other mold, and the pair of groove ejector pins press the semiconductor part against the other mold. The mold is separated by a minute distance while being held in one of the molds, and the semiconductor portion and the groove portion are separated while remaining in each mold, and then the mold is completely separated. A method for resin-sealing a semiconductor element, characterized in that the other body ejector pin and the one groove ejector pin are released from the mold by protruding. 2) A groove consisting of a cavity for a semiconductor element connected to an electrode material on the separation surface between the upper mold and the lower mold, and a gate and a runner continuous with this cavity and provided in one of the upper mold or the lower mold. The mold includes a pair of upper and lower body ejector pins that protrude the semiconductor element portion, and a pair of upper and lower groove ejector pins that protrude the groove portion in an area where the electrode material does not exist, and the mold includes: One of the main body ejector pins and one of the lipor pins are fixed to a first ejector plate provided on one mold and biased toward the separation surface by a first spring, and the tip of the one lipor pin is attached to the separation surface. , the tip of the one main body ejector pin is in a position where it can be molded with resin, and is disposed on the separation surface side with a gap between the first ejector plate and a second spring in the direction opposite to the separation surface. second energized
One of the grooved ejector pins is fixed to the ejector plate, and one stopper bolt is provided, and when the second ejector plate is biased by the second spring and stops at the one stopper bolt, The tip of the groove ejector pin is in a position where it can be molded with resin; The other of the grooved ejector pins and the other Liptor pin are fixed to the ejector plate of No. 3, and when the tip of the other Liptor pin matches the separation surface, the tip of the other grooved ejector pin is in a position where resin molding can be performed. The other of the main body ejector pins is fixed to a fourth ejector plate that is disposed on the anti-separation surface side through a gap in the third ejector plate and is biased in the anti-separation surface direction by a fourth spring. At the same time, another stopper bolt is provided, and when the fourth ejector plate is urged by the fourth spring and stops at the other stopper bolt, the tip of the other main body ejector pin is in a position where resin molding is possible. A resin-sealed mold for a semiconductor element, wherein the other mold is provided with an ejector rod that pushes out the fourth ejector plate against the fourth spring.