JP3002226U - Semiconductor element resin sealing device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a resin sealing device that simplifies the structure of a mold and can easily adjust the lifting speed of the plunger. [Structure] A large number of cavities (9) are arranged in at least a pair of rows in the upper and lower molds (1) and (2). A pot (17) is provided in the middle of a row of cavities forming a pair in the lower die (2) so as to correspond to the cavities (9), and each pot (17) and a pair of corresponding pots (17) are formed. The cavity (9) communicates with the gate (18). A plunger (19) is attached to the bottom of each pot (17), and the lower end of this plunger (19) is attached to the plunger mounting plate (20) via a buffer mechanism (21).
To accept. The plunger mounting plate (20) was configured to be moved up and down by the servo motor (22).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a resin encapsulation device for encapsulating a semiconductor element with a resin, and more particularly to improvement of a press-fitting mechanism for supplying encapsulation resin to a cavity.

[0002]

[Prior art]

 2. Description of the Related Art Conventionally, as a resin encapsulating device for encapsulating and molding a semiconductor element component with a resin, one disclosed in Japanese Patent Publication No. 58-50582 is known. This is because a large number of cavities are provided in the abutting surface so as to face each other, and a plunger insertion hole is directly opened in each cavity, and the plunger insertion hole is used as a pot. The plungers that were fitted and arranged were configured to reciprocate individually by oil pressure from a common oil source.

[0003]

[Problems to be solved by the device]

 However, in this conventional resin sealing device, since many plungers are configured to be driven by the oil pressure from a common oil source, an oil passage must be formed in the mold and the plungers must be formed. Since the cylinder portion must be formed at the lower end of the insertion hole, the structure of the mold becomes complicated, and the manufacturing cost and maintenance cost of the mold increase. Another problem is that adjusting the plunger lifting speed is troublesome because the lifting speed of the plunger is determined by the amount of supplied oil. The present invention has been made paying attention to such a point, and an object thereof is to provide a resin sealing device that simplifies the structure of the mold and that can easily adjust the lifting speed of the plunger.

[0004]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention arranges a large number of cavities in upper and lower molds of a compression molding device in at least one pair of rows and arranges a pot in the middle of a row of cavities paired with a lower mold. Each of the pots and the corresponding cavity are connected by a gate, and a plunger is attached to the bottom of each pot. It is characterized in that it is configured to be received by the plunger mounting plate via a cushioning mechanism using the above, and the plunger mounting plate is driven up and down by a servo motor.

[0005]

[Action]

 In the present invention, since the plunger mounted on the bottom of the pot is configured to be lifted and lowered by the servo motor, it is not necessary to form an oil passage for driving the plunger in the mold, and the structure of the mold is not required. Is simplified. Also, since the lower end of the plunger is received by the plunger mounting plate via a cushioning mechanism, this cushioning mechanism can eliminate pressure differences caused by the filling amount error of the molding material (resin) filled in the pot and the molding error of the gate. It can be absorbed to obtain a homogeneous molded product. In addition, since the servo motor drives the plunger up and down, the resin injection speed from the pot to the cavity can be easily adjusted.

[0006]

【Example】

 FIG. 1 shows an embodiment of the present invention and is a schematic vertical cross-sectional view of a mold device for resin-sealing a semiconductor element. This semiconductor device resin sealing mold device is composed of a fixed upper mold (1), a movable lower mold (2), and a pressing device (3) that supports both molds (1) and (2). In this configuration, a lead frame with a semiconductor chip attached is set on the abutting surfaces of both molds (1) and (2), and the chip is encapsulated with a thermosetting synthetic resin material such as epoxy resin. It was done.

The fixed mold (1) has an upper mold mounting plate (5) attached to the lower surface of the upper fixed frame (4) of the press device (3) via a heat insulating plate, and below the mounting plate (5). Upper ejector plate (7) is placed on the side of the ejector plate (7) via compression springs (6) so that it can be contacted and separated, and the lower part of the ejector plate (7) is maintained with the required thrust distance (H1). The upper die (1) is arranged on the receiving plate (8). Then, a plurality of cavities (9) formed together with a lower mold (2) which will be described later are recessed in a plurality of pairs of rows on the lower surface of the upper mold (1).

In the fixed upper mold (1), ejector pins (10) that are capable of projecting and retracting are arranged in the respective cavities (9), and the ejector pins (10) receive the upper mold receiver. It penetrates the plate (8) and the upper mold (1) and is fixed to the upper ejector plate (7). Moreover, the upper return pin (11) is fixed to the upper ejector plate (7), and the upper return pin (11) penetrates the upper die receiving plate (8) and the tip portion thereof is the upper die receiving plate. It is projected below (8).

The movable lower mold (2) is provided with a lower ejector plate (15) via a heat insulating plate (14) on a base frame (13) fixed to a lower slide table (12) of a pressing device (3). The lower die receiving plate (16) is placed above the lower ejector plate (15) via a spring, and the lower die (2) is placed above the lower die receiving plate (16). There is a thrusting interval (H2) between the lower die support plate (16) and the lower die (2).

As shown in FIG. 2, cavities (9) formed together with the above-mentioned upper mold (1) are recessed in a plurality of pairs of rows on the upper surface of the lower mold (2). At the same time, pots (17) for injecting the molding resin material are recessed in the middle portion of each pair of cavity rows by the number of cavities forming each cavity row. A gate (18) is formed from each pot (17) toward the cavity (9) corresponding to the pot (17).

Plungers (19) are arranged facing the bottom of each pot (17), and the lower end of each plunger (19) is attached to a plunger mounting plate (20) by a pressure buffering mechanism (21). Are connected through. The plunger mounting plate (20) is supported on the slide table (12) so as to be able to move up and down, and is configured to be moved up and down by the operation of the servo motor (22) arranged on the lower surface of the slide table (12). There is.

As shown in FIG. 3, the pressure buffering mechanism (21) arranged between the lower end of the plunger (19) and the plunger mounting plate (20) has a disc spring (23) arranged in parallel with each other. Are combined in four stages in series. The pressure buffer mechanism (23) may be constructed by using a coil spring (24) as shown in FIG.

The power transmission mechanism from the servo motor (22) to the plunger mounting plate (20) is composed of a speed reducer that reduces the output of the servo motor (22), a belt transmission device, and a ball screw mechanism. In addition, a load cell is arranged between the ball screw mechanism and the connecting rod (25) drawn downward from the plunger mounting plate (20). Further, the lifting / lowering drive mechanism of the slide table (12) is configured by transmitting the output of another servo motor to the ball screw mechanism via the timing belt mechanism.

In the above embodiment, the pots (17) are provided on the upper surface of the lower mold (2) so as to correspond to the pair of cavities (9), respectively. You may make the connection through a narrow communication passage.

[0015]

[Effect of device]

 In the present invention, since the plunger mounted on the bottom of the pot is configured to be lifted and lowered by the servo motor, it is not necessary to form an oil passage for driving the plunger in the mold, and the structure of the mold is not required. Can be simplified. Also, since the lower end of the plunger is received by the plunger mounting plate via the buffer mechanism, the pressure difference caused by the filling amount error of the molding material (resin) filled in the pot and the molding error of the gate is buffered. It can be absorbed by the mechanism to make the applied pressure uniform and obtain a homogeneous molded product. Furthermore, since the servo motor drives the plunger up and down, the resin injection speed from the pot to the cavity can be easily adjusted.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a mold device that seals a semiconductor element with a resin.

FIG. 2 is a plan view of a lower mold.

FIG. 3 is an enlarged vertical sectional view of a pressure buffer mechanism.

FIG. 4 is an enlarged vertical sectional view showing another embodiment of the pressure buffer mechanism.

[Explanation of symbols]

1 ... Upper mold, 2 ... Lower mold, 9 ... Cavity, 17 ... Pot, 18 ... Gate, 19 ... Plunger, 20 ... Plunger mounting plate, 21 ... Buffer mechanism, 22 ... Servo motor, 23 ... Disc spring.

Claims (2)

[Scope of utility model registration request] 1. Upper and lower molds (1) and (2) having a plurality of cavities (9) concavely formed on the abutting surface so as to face each other are configured to be movable toward and away from each other, and a pot is provided in each cavity (9). In a resin sealing device for a semiconductor element, in which a large number of semiconductor elements are simultaneously resin-sealed by press-fitting a synthetic resin from the portion (17), a plurality of cavities (9) are provided in the upper and lower molds (1) and (2). ) Are arranged in at least a pair of rows, and a pot (17) is provided in each of the cavities (9) in the middle of the row of cavities that are paired with the lower mold (2).
The pots (17) and the pair of cavities (9) corresponding to the pots (17) communicate with each other through the gates (18), and the plungers (1) are attached to the bottoms of the pots (12).
9) and attach the lower end of this plunger (19) to the buffer mechanism (2
A resin sealing device for a semiconductor element, characterized in that it is received by a plunger mounting plate (20) via 1), and the plunger mounting plate (20) is driven up and down by a servomotor (22). 2. A disc spring (30), which is a parallel combination of buffer mechanisms (21) arranged between the lower end of the plunger (19) and the plunger mounting plate (20), is arranged in series. The resin sealing device for a semiconductor element according to claim 1.