JPH0744192B2 - Mold for resin encapsulation molding of semiconductor element - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement in a resin encapsulation molding die for a semiconductor element for producing a semiconductor device by encapsulating an IC, an LSI or the like with a resin,
In particular, the present invention relates to an improved resin encapsulation molding die for a semiconductor element, which is suitable for the case where a large variety of semiconductor devices are produced in small quantities.

(Prior Art) It is widely known today to adopt a transfer resin molding method as a method for manufacturing a semiconductor device. For example, as a mold for resin encapsulation molding using this method, JP-B-58-39889. There is one described in the publication.

This resin encapsulation molding die is mainly intended for high quality and high-efficiency (high-volume) production of semiconductor devices. Therefore, all the resin molding cavities in the cavity block are formed to have the same shape. The cavity block is configured to be fixedly used on the mold base.

That is, since the conventional type has the main purpose of simultaneously molding a large number of semiconductor devices having the same shape at the same time, the conventional cavity block having the same shape of cavity is different from other mold bases. It is not designed to have the positive exchangeability that it is frequently replaced.

(Problems to be Solved by the Invention) In the conventional mold for resin encapsulation molding as described above, there is an improvement in processing technology of the mold itself and complete automation of all resin encapsulation processes. Thus, the objectives of high quality and high efficiency production of semiconductor devices have been sufficiently achieved.

However, at the time of manufacturing a semiconductor device, for example, in the initial stage, since there is a tendency for high-mix low-volume production, in the case where high-mix low-volume semiconductor devices are individually produced, the cavity block There is an adverse effect that the replacement work becomes troublesome and the overall production efficiency is lowered.

It is an object of the present invention to provide a resin encapsulation molding die suitable for producing small quantities of various types of resin encapsulation molded products of semiconductor elements.

Further, in particular, it is an object of the present invention to improve the overall production efficiency by promptly and reliably performing the attachment / detachment work when replacing the cavity block in the resin encapsulation molding die of the semiconductor element.

(Means for Solving the Problems) A resin encapsulation molding die for a semiconductor element according to the present invention for solving the above-mentioned technical problem is provided with both fixed-side and movable-side cavity blocks (7, 8). Are molds (1.2) for resin encapsulation molding of a semiconductor element in which the metal mold bases (3, 4) on both the fixed side and the movable side are detachably mounted to the fitting mounting parts. Then, both cavity blocks (7.
8) At least the tip side (8b, 8d) and the engaging portion (4c, 4e) of at least the cavity block tip side (8b, 8d) in the fitting mounting portion of both mold bases (3.4). A positioning engagement portion (40) for fitting and mounting the cavity block (7.8) at a predetermined fitting mounting position of the mold base (3.4), and the positioning engagement portion (4)
The cavity blocks (7, 8) are removably positioned and locked to the mold bases (3, 4) via the (0).

(Operation) According to the configuration of the present invention, it becomes easy to attach and detach both the fixed side and movable side cavity blocks (7.8) to the fixed side and movable side mold bases (3.4), respectively. The time required to replace the cavity block (7, 8) can be shortened.

The cavity block (7.8) and the fitting mounting portion of the mold base (3, 4) at the predetermined fitting mounting position are the cavity block (7.8) and the fitting mounting portion. The positioning and engagement portions (40) provided on both of the parts make it possible to easily position and securely engage and fix at the predetermined position.

(Example) Next, this invention is demonstrated based on an Example figure.

FIG. 1 shows a main part of a resin encapsulation molding die for a semiconductor element, and this resin encapsulation molding die has a fixed upper die fixed to a stationary platen (not shown) side of an upper end of a frame. 1, a movable lower mold 2 arranged below the upper mold so as to face each other, and the two molds 1
The heat sources 5 and 6 such as oil or a heater arranged on the bases 3 and 4 side of 2 are provided.

A fixed side cavity block 7 is removably fitted and mounted on the upper mold base 3 by a kind of dovetail groove fitting, and a movable side cavity block 8 is similarly mounted on the lower mold base 4 as a kind of dovetail. It is detachably fitted and mounted by groove fitting.

Further, a plurality of required pots 9 are arranged in the vertical direction in the movable side cavity block 8 described above.
A plurality of required lower mold cavities 10 (two cavities for one pot in the illustrated example) are provided around the pots 9. In the vicinity of the lower mold cavity 10 in the cavity block 8, there is provided a heat source 11 of a heating / adiabatic switching type which will be described later and is formed in a long axis shape. Further, below the cavity block 8, a lower ejector plate 12 having ejector pins 12a for projecting a resin molded body molded in the lower mold cavity 10 and a resin material supplied into the pot 9 are added. Plunger holder 13 with pressure plunger 13a
And the ejector pins 12a.
Is a vertical through hole 14 formed in each lower mold cavity 10
And the plungers 13a are inserted into the lower die base 4 and the ejector plate 12, respectively.
The pots 15 and 16 are inserted and fitted into the pots 9, respectively. Further, at least one vertical screw hole 17 is formed in the fitting dovetail portion 8a of the cavity block 8, and the screw hole 17 is formed in the lower part of the cavity block 8 as shown in FIG. When fitted in predetermined positions of the die base 4, they are provided so as to respectively match with the vertical bolt insertion holes 18 formed in the dovetail groove portion 4a of the lower die base. Therefore, the cavity block 8 can be securely fixed to a predetermined position of the lower mold base 4 by screwing the fixing bolt 19 into the screw hole 17 through the insertion hole 18 described above.

In addition, the heat source 11 of the movable side cavity block 8 described above
Is configured to be heated by a power source (not shown) arranged on the base 4 side after being fitted and mounted on the lower die base 4, and further, in the cavity block heated by the heat source 11. When the temperature of the cavity 10 reaches an arbitrary set temperature, for example, about 180 degrees, the positive and direct heating operation of the cavity 10 by the heat source 11 is stopped, and thereafter the lower mold base 4 side. Only the heating action by the conduction heat of the heat source 6 is continued. As the heat source 11 of such a heating / adiabatic switching type, for example, an electric heater may be adopted for the heat source 11. That is, in this case, the shaft end of the heat source 11 is provided so as to project from the side surface of the cavity block 8, and the lower die base 4 side is electrically connected to the shaft end (connection to the power source side). (Not shown), and the shaft end and the insertion hole are electrically connected to the insertion hole based on the detection signal from the temperature detector of the cavity 10. A temperature controller (not shown) for connecting / disconnecting to and from may be arranged. Therefore, in this case, when the cavity block 8 at room temperature is fitted in a predetermined position on the lower die base 4, the controller first heats the long-axis heat source 11, and then,
The amount of heat heats the cavity block 8. Further, when the cavity 10 in the cavity block 8 reaches the preset temperature by the heat source 11, the controller stops the heating and heating action of the heat source 11 itself, so that the cavity block 8 is heated by the lower mold base. Only the conduction heat from the heat source 6 of the lower mold base 4 is transmitted from the joint surface with the 4 side and the like. At this time, the temperature of the lower mold base 4 is usually set equal to the above-mentioned set temperature (about 180 degrees), so that the cavity block 8 is eventually set.
The cavity 10 part in the above is rapidly heated up to the temperature of the lower mold base 4 side and does not reach a higher temperature, so if the cavity 10 part is maintained at a preset proper resin molding temperature state. The temperature control of the cavity 10 portion is ensured.

By the way, when an electric heater is used for the long-axis heat source 11, for example, the calorific value of the intermediate portion and both end portions thereof may not be constant. Therefore, in this case, each cavity 10 in the cavity block 8 is This will cause variations in the heating of the parts. In order to eliminate such temperature variations during heating, the heat source 11 has
It is preferable to apply a thermopipe (super heat conduction element) that can evenly generate heat over the whole and can evenly heat each of the cavities 10 by the amount of heat.

That is, in this thermopipe, the heat source (11) is, for example, a hollow pipe-shaped container body made of stainless steel or the like,
The heat medium is composed of a heat medium such as mercury (not shown) housed in the main body and is heated by a power source on the side of the base 4. In this case, the heat source itself is
It can be heated in the range of 180 to about 500 degrees. Therefore, when using such a thermopipe, the heat source (11)
Since there is no temperature variation in itself, the cavities 10 of the cavity block 8 can be heated evenly, which has the advantage that the above-mentioned adverse effects of the temperature gradient in the electric heater can be corrected. . The temperature control of each cavity by heating and heat insulation of the thermopipe itself can be surely performed by a controller, like the temperature controller, and the base (3.4) side can be controlled. The heat source (5, 6) may use oil.

The arrangement of the upper die base 3, the fixed side cavity block 7 and its heat source (21) is substantially the same as the arrangement of the lower die base 4, the movable side cavity block 8 and its heat source 11. .

That is, the fixed cavity block 7 is provided with a plurality of required upper mold cavities 20 so as to face the lower mold cavities 10, and in the vicinity of the cavities 20, a long-axis heating / adiabatic switching is provided. A flexible heat source 21 is provided. An upper ejector plate 22 having an ejector pin 22a is provided above the cavity block 7,
A support pin 22b of the upper ejector plate 22 and a spring 23 that pushes down the upper ejector plate 22 via the support pin 22b are provided.

As shown in FIG. 1, each of the ejector pins 22a described above is fitted in a vertical insertion hole 25 formed in a cull portion 24 facing the upper mold cavity 20 portion and each pot 9 on the lower mold 2 side. It is equipped. In addition, the above ejector plate 22
When the mold is opened as shown in FIG. 1, the resin is hardened in the upper mold cavity 20 and the cull part 24 and the gate part 26 that connects the upper mold cavity 20 and the cull part 24 by being pushed down by the elasticity of the spring 23. Each of the resin molded bodies is ejected.

At this time, the lower ejector plate 12 is pushed up by the ejector bar 12b, and similarly the resin molded body in the lower mold cavity 10 is projected. However, when the lower mold 2 side is raised and both molds (1, 2) are clamped at the parting line (P, L) surfaces, the above-mentioned upper and lower ejector plates (22, 12)
The upper and lower return pins (not shown) arranged to face each other retract the ejector plates (22, 12) upward and downward, respectively.

Therefore, a semiconductor element (not shown) on the lead frame is set at a predetermined position in both upper and lower cavities 20 and 10 by its attaching / detaching mechanism, and then a resin material is supplied into the lower mold pot 9 so that both molds (1 When the mold material of (2) is clamped and then the resin material in the lower mold pot 9 is pressed by the plunger 13a, the resin material is heated and melted and the upper mold cull portion 24
Also, transfer resin molding in which pressure is injected into both upper and lower cavities 20 and 10 through the gate portion 26 to seal the semiconductor elements in both cavities with resin can be performed.

Further, the fixed cavity block 7 is provided with the same configuration (the dovetail portion 7a and the dovetail groove portion 3a) as the dovetail portion 8a and the dovetail groove portion 4a in the movable cavity block 8 and the lower die base 4, and the The same structure as the fixing means including the hole 17, the insertion hole 18, and the bolt 19 is provided.

Further, the structure of the heat source 21 of the fixed side cavity block 7,
Regarding the positional relationship between the heat source 21 and the power source on the upper mold base 3 side and the temperature control of the upper mold cavity 20 in the cavity block 7, the same structure as that on the lower mold 2 side described above (illustration) None).

To attach and detach the cavity block 8 on the lower die 2 side, for example, the cavity block 8 and the lower ejector plate 12 may be integrally fitted and detached at the same time while the plungers 13a are moved downward. Good. In addition, the attachment / detachment of the cavity block 7 on the upper mold 1 side is
For example, with the upper ejector plate 22 and its support pins 22b removed, the cavity block 7
The upper ejector plate 22 and the upper ejector plate 22 may be integrated and disengaged at the same time.

That is, the cavity block (7, 8) is the base (3
• It can be securely and easily attached / detached by a simple means of fitting to 4).

3 to 6 show the cavity block (7.
In the case of attaching and detaching 8) to and from the base (3, 4), in particular, a configuration example for easily fitting and mounting the cavity block and securely locking it at a predetermined position is shown. Since this structure can employ substantially the same structure in both upper and lower molds (1 and 2), only the lower mold 2 will be described below.

As described above, the cavity block 8 and the lower mold base 4 are detachably configured by a kind of dovetail groove fitting (8a, 4a), but as shown in FIG. 8a and the dovetail groove 4a on the base side are formed as follows.

That is, as shown in the figure, the width W of the upper portion of the cavity block 8 is narrower than the width W ₁ of the fitting portion of the base.
It will be in a free state when attaching or detaching.

Further, the tip portion 8b of the dovetail portion 8a of the cavity block 8 and the dovetail groove portion 4a of the base fitted with the tip portion 8b.
The width W ₂ with the fitting portion 4c of is formed with high precision so that both fitting portions (8b and 4c) form the positioning engaging portion 40 of the cavity block 8 and the rear portion of the dovetail portion 8a. The width W ₃ between the end portion 8c and the fitting portion 4d of the dovetail groove portion 4a that is fitted with the end portion 8c also constitutes the positioning engagement portion 40 ₁ that is also formed with high precision. Both mating parts (8b
・ 4c, 8c and 4d) are closely fitted and mounted.

Further, the width W ₂ of the tip portion 8b is narrower than the width W ₃ of the rear end portion 8c, and a space between the tip portion 8b and the rear end portion 8c is free with respect to the dovetail groove portion 4a. It is provided in the state. Therefore, the cavity block 8 can be simply fitted into the base 4 in a free state, and
The fitting at a predetermined position is in a state of being securely mounted by the positioning engaging portions (40, 40 ₁ ) at the front end and the rear end which are provided with high accuracy.

Further, instead of the positioning engaging portion 40 formed by the tip portion 8b and the fitting portion 4c, or together with the positioning engaging portion 40, a positioning protrusion 8d provided on the tip end surface of the cavity block 8 and the base 4 side. The positioning engagement portion 40a may be formed by the provided positioning protrusion 8d and the engagement recess 4e.

Further, as a positioning means for the cavity block 8, balls 35a provided between the cavity block 8 and the base 4 side, a ball spring 35b, and a fixture 35c are provided.
A positioning member 35 composed of, for example, may be provided together. A configuration may be adopted in which the tip of the fixture 35c is directly inserted into and removed from a hole (not shown) for confirming a predetermined position provided on the side surface of the dovetail portion 8a.

Further, after fitting the cavity block 8 in a predetermined position of the base 4, a stopper pin 36 fitted in the cavity block 8 is formed in the base 4 as shown in FIGS. 3 and 4. The cavity block 8 is configured to be prevented from coming off by engaging with the engaging hole 4f. Further, as shown in FIG. 4, the shaft diameter of the stopper pin 36 is formed smaller than the hole diameter of the engagement hole 4f, which is, as described above, the cavity 10 portion of the cavity block 8. This is because when the temperature is raised to a predetermined temperature, the cavity block 8 and the base 4 are satisfactorily fitted by utilizing their thermal expansion.

Further, in addition to the above-described configuration of the positioning engaging portions 40, 40 ₁ , 40 ₂ and the positioning member 35, as shown in FIG. 4, the cavity block 8 is provided on both the dovetail portion 8a and the dovetail groove portion 4a.
Tapered surface 37 that inclines so that it becomes narrower toward the tip side of
By forming the above, the cavity block 8 and the base 4 may be fitted smoothly. Further, as shown in FIG. 5, the taper surface 37a on the side of the dovetail groove 4a is located at a plurality of places which are fitted to the taper surface 37b on the side of the dovetail portion 8a when the cavity block 8 and the base 4 are fitted. It may be formed only on the end face. Further, the plurality of tapered surfaces 37a are tapered surfaces 37b on the dovetail side.
However, instead of such a tapered surface 37a, a horizontal surface 37c as shown in FIG. 6 may be formed. In this case, the taper surface 37b on the side of the dovetail portion comes into line contact (in this case, a similar horizontal surface may be formed on the corresponding surface on the side of the dovetail portion 8a). The fitting operation can be smoothly performed when fitting the cavity block 8 to the base 4, and the cavity block 8 is fitted to the base 4 with high accuracy and tightly only when the fitting is performed at a predetermined position. It can be attached.

Incidentally, projections 8d and recess 4e in the positioning engagement portion 40 ₂ described above, the positioning member 35, a stopper mechanism comprising a stopper pin 36 and the engaging hole 4f or the like, each tapered surface provided in the dovetail portion and the dovetail groove portion ( 37, 37a, 37b) and the horizontal plane 37c are arranged relative to each other between the cavity block (7.8) and the base (3.4). It can be appropriately and arbitrarily changed in accordance with the design and manufacture of the mold for sealing molding or the actual usage thereof.

In addition, reference numeral 39 in the drawing indicates the cavity block (7.
8 shows a block for fixing both ends of the tip of 8).

As described above, according to the above-described embodiment, it becomes easy to attach and detach both the fixed side and movable side cavity blocks (7.8) to the fixed side and movable side bases (3.4), respectively.
Therefore, it is possible to shorten the time required to replace the two cavity blocks.

Further, when replacing both the cavity blocks (7, 8), the cavity blocks can be easily and surely locked and mounted at predetermined positions of the base (3, 4).

(Advantageous Effects of Invention) According to the configuration of the present invention, since the cavity block has a positive exchangeability such that the cavity block is frequently exchanged with respect to the mold base, both the fixed-side and movable-side mold bases are provided. On the other hand, it is most suitable as a resin encapsulation mold for semiconductor elements for the purpose of high-mix low-volume production of semiconductor devices in which both fixed and movable cavity blocks are frequently replaced.

Further, according to the configuration of the present invention, when exchanging the cavity block with respect to the mold base, the attachment / detachment work can be performed simply, quickly and surely. It has an excellent practical effect that can be solved.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a partially cut-away schematic vertical front view showing a main part of a resin sealing molding die according to the present invention, and FIG. 2 is the resin sealing molding. FIG. 3 is a partially cutaway plan view showing an essential part of the lower mold in the resin sealing molding mold, and FIG. 4 is a dovetail part of the lower mold cavity block and the lower mold base. FIG. 5 and FIG. 6 are exploded front views showing the dovetail groove portion of FIG. 5 and FIG. 6 and FIG. (Explanation of symbols) 1 ... Fixed upper mold 2 ... Movable lower mold 3 ... Upper mold base 3a ... Dovetail groove 4 ... Lower mold base 4a ... Dovetail groove 4c ... Fitting part 4d ... Fitting Part 4e ...... Engagement recess 4f ...... Engagement hole 5 ...... Heat source 6 ...... Heat source 7 …… Upper mold cavity block 7a …… Dove part 8 …… Lower mold cavity block 8a …… Dove part 8b …… Tip Part 8c …… Rear end part 8d …… Positioning projection 9 …… Pot 10 …… Lower mold cavity 11 …… Heat source 12 …… Lower ejector plate 12a …… Ejector pin 12b …… Ejector bar 13 …… Plunger Holder 13a …… Plunger 14 …… Insertion hole 15 …… Insertion hole 16 …… Insertion hole 17 …… Screw hole 18 …… Bolt insertion hole 19 …… Fixing bolt 20 …… Upper cavity 21 …… Heat source 22… … Upper ejector plate 22a …… Ejector pin 22b …… Support pin 23 …… Ring 24 …… Cull section 25 …… Insertion hole 26 …… Gate section 35 …… Positioning member 35a …… Ball 35b …… Ball spring 35c …… Fixing tool 36 …… Stopper pin 37 …… Tapered surface 37a …… Tapered surface 37b …… Tapered surface 37c …… Horizontal surface 39 …… Block 40 …… Positioning engagement part 40 ₁ …… Positioning engagement part 40 ₂ …… Positioning engagement part W …… Width W ₁ …… Width W ₂ …… Width W ₃ ...... width

Claims (1)

[Claims] 1. A resin encapsulation molding of a semiconductor element, wherein both fixed and movable cavity blocks are detachably mounted to a fitting mounting portion provided on both fixed and movable mold bases. The mold is a mold, and the cavity block is fitted to the mold base in a predetermined manner at an engaging portion of at least the tip side of both the cavity blocks and at least the tip side of the cavity block in the fitting mounting portions of the mold bases. A semiconductor device characterized in that a positioning engaging portion for fitting and mounting is formed at a mating mounting position, and the cavity blocks are removably positioned and locked to the mold bases through the positioning engaging portion. Mold for resin encapsulation molding of elements.