JPH07254624A - Manufacture of semiconductor device, lead frame therefor and molding equipment - Google Patents

Abstract

PURPOSE:To utilize a resin efficiently while suppressing the difference of filling time in transfer molding. CONSTITUTION:Twelve groups of unit lead frames are arranged in grid of two rows thus preparing a multiple row multiple lead frame 10 where a resin sump 18 is formed in the center of a set of four lead frames 13. An assembly 27, pellet wire bonded to the multiple lead frame 10, is sandwiched by upper and lower dies and both cavities, corresponding to the front unit lead frames 12 of the set 13 of lead frames are filled with resin. Subsequently, both cavities corresponding to the rear unit lead frames are filled with resin through a resin sump cavity 40 corresponding to the resin sump 18. Since the difference of time for filling the front cavities with resin is absorbed by the resin sump cavity, the time difference can be avoided when the rear cavities are filled with resin. Furthermore, the quantity of resin can be saved because the resin is carried through each cavity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for manufacturing a semiconductor device, and more particularly to a technique for molding a resin encapsulation body of a resin encapsulation package, for example, for molding a semiconductor integrated circuit device or a resin encapsulation package of a transistor. Related to effective technology.

[0002]

2. Description of the Related Art Generally, semiconductor integrated circuit devices (hereinafter referred to as I
Called C. ), Or in the field of manufacturing semiconductor devices such as individual semiconductor devices such as transistors, etc., a pellet in which a semiconductor integrated circuit or a transistor circuit is formed and a plurality of electrically connected pellets. A resin-sealed package is widely used as a package for sealing the leads of a book. It is usual that the resin sealing body of this resin sealing package is molded using a transfer molding device.

Then, as a transfer molding apparatus used for molding the resin encapsulation body of the resin encapsulation package, an upper die and a lower die, and a cavity formed on a mating surface of the upper die and the lower die. , A small gate is provided at one end of one side wall of the cavity in either the upper mold or the lower mold, and a runner and a pot fluidly connected to all of the gates are provided. A lead frame is sandwiched between the mold and the pellet so that it fits inside the cavity, and a resin (hereinafter referred to as resin) as a molding material is injected into the cavity through a pot, a runner, and a gate, thereby forming a resin-sealed body. Are configured to mold.

By the way, once used as a molding material, a resin (hereinafter referred to as a resin) cannot be reused. In the conventional transfer molding apparatus as described above, the pot and runner in the central portion are formed to have a large cross-sectional area in order to make the flow pressure of the resin uniform. Therefore, the utilization efficiency of the used resin is extremely low.

Therefore, conventionally, in order to improve the utilization efficiency of the resin, JP-B-61-2755 and JP-A-58-1.
84839, JP-A-61-194730,
JP-A-62-122136, JP-A-63-137
As described in Japanese Patent Publication No. 23, etc., a molding apparatus called a so-called through molding apparatus in which the runner is eliminated or reduced is proposed.

That is, in this through molding apparatus, a plurality of cavities are arranged in series on the mating surface of the molding die, and the downstream cavities connect to the upstream cavities. Each of the cavities is directly fluidly connected to each other, and each cavity is configured so that the resin is injected and filled through the upstream cavity and the communication passage. Further, since the resin is directly injected and filled into each cavity through the communication path, the resin utilization efficiency is improved.

[0007]

However, in such a through-molding apparatus, the resin is sequentially filled while sequentially flowing down a plurality of cavities through the through gates, so that the resin flow is unstable. become,
The present inventor has revealed that there is a problem that a filling time difference occurs between the cavity located at the most upstream and the cavity located at the most downstream.

An object of the present invention is to suppress the difference in filling time,
It is an object of the present invention to provide a semiconductor device manufacturing method capable of improving the resin utilization efficiency, and a lead frame and a molding device used for the same.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0010]

The typical ones of the inventions disclosed in the present application will be outlined below. That is, a semiconductor pellet in which an electronic circuit is built, a plurality of leads electrically connected to the electronic circuit of the semiconductor pellet, and a package in which the semiconductor pellet and a part of each lead are resin-sealed. A method of manufacturing a semiconductor device, comprising: at least four unit lead frames each having the lead group and an outer frame that integrally supports the lead group. A lead frame preparation step for preparing a multi-row multi-row lead frame in which a unitary lead frame group of four pieces is arranged in series and a resin reservoir is formed in a central portion of the unit lead frame group; An assembly in which a semiconductor pellet is bonded to the multiple multi-row lead frame and electrically connected to each lead is the resin-sealed package. The resin encapsulating body is sandwiched by a molding die for molding, and after each cavity corresponding to the unit lead frame in the front row in the unit lead frame group of four sets is filled with resin, And a molding step of filling the respective cavities corresponding to the unit lead frames in the rear row with the corresponding resin reservoir cavities.

[0011]

According to the above-mentioned means, the resin in the molding process of the resin sealing body is filled in each cavity in the front row and then in each cavity in the back row through the common resin reservoir cavity. . Even if there is a resin filling time difference between the front row cavities, the resin after filling the front row cavities fills the common resin reservoir cavity at the same time, so the filling time difference is It will be resolved once.
Therefore, it is possible to prevent a difference in filling time of the resin between the cavities in the rear row. That is,
Since the stability of the resin flow as a whole is ensured, the quality and reliability of the resin-sealed package can be improved.

Then, the resin is sequentially filled in the cavities and is conveyed to the downstream side through the cavities, and the resin is adjacent to each other corresponding to each unit lead frame of the multi-row multi-row lead frame. Since they are aligned, the amount of resin used is kept low.

Further, by using the multi-row multi-row lead frame and the molding apparatus corresponding thereto, it is possible to manufacture a large number of products by one molding operation. Furthermore, since the resin-sealed package and the cavities are arranged at a high density, the occupied area and the material yield can be improved, and the mold clamping pressure can be reduced.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an exploded perspective view showing essential parts of a multiple-row multi-row lead frame and a molding apparatus according to an embodiment of the present invention. 2 and subsequent drawings are explanatory views showing a method of manufacturing a semiconductor device which is an embodiment of the present invention using the same. FIG. 6 shows a QFP / IC manufactured thereby, and (a)
Is a partially cut front view, and (b) is a partially cut plan view.

In the present embodiment, the semiconductor device manufacturing method according to the present invention is a quad flat package (hereinafter also referred to as QFP) which is an example of an IC having a surface mount type resin-sealed package. .) Is used to manufacture an IC (hereinafter, referred to as QFP / IC). Then, as shown in FIG. 6, the QFP2 of the QFP / IC1 manufactured by this method and the resin sealing body 28 integrally molded using a resin into a relatively thin flat plate shape of a substantially square shape. , And a plurality of outer leads 3 formed in a gull-wing shape. The outer leads 3 are aligned with the four side surfaces of the resin encapsulation body 28, and the outer leads 3 are aligned and projected so that the back surface thereof protrudes slightly more than the back surface of the resin encapsulation body 28.

A QFP.I which is an embodiment of the present invention will be described below.
A method of manufacturing C will be described. In this embodiment, first, a multi-row multi-row lead frame as shown in FIG. 2 is prepared. This multi-row multi-row lead frame 10 is a thin plate made of a copper-based (copper or alloy thereof) material such as phosphor bronze or oxygen-free copper, or an iron-based (iron or alloy thereof) material such as 42 alloy or Kovar. Is integrally formed by a suitable means such as punching press working or etching working. A multiple lead frame 11 is configured by arranging a plurality of unit lead frames 12 in a row in one direction (hereinafter referred to as a left-right direction) in the multiple-row lead frame 10. Continuous lead frame 1
Two rows of 0s are arranged side by side in parallel with each other so as to be integrated. A plurality of sets (hereinafter, referred to as a lead frame set) 13 including four unit lead frames 12 as one set are continuous in the left-right direction. However, in the illustrated example and the following description, only one set in which continuity can be understood is shown. The same applies to other configurations below.

The lead frame set 13 is provided with a pair of outer frames 14, and both outer frames extend in parallel in series at predetermined intervals. The outer frame 14 is provided with a circular positioning hole 14a and an oval positioning hole 14b. Four unit lead frames 12 are arranged symmetrically in the front-rear direction and the left-right direction in a substantially square frame body formed by the outer frames 14, 14. The lead frame set 13 and each unit lead frame 12 are configured as follows.

A common frame 15 is provided on the opposite side of the outer frame 14 in the lead frame set 13 in the front and rear unit lead frames 1.
It is formed so that 2 and 12 are common. A pair of section frames 16 are disposed between the left and right unit lead frames 12, 12 so as to be parallel to each other between the outer frame 14 and the common frame 15, and are integrally erected. Further, the unit lead frame 12 is formed in a substantially square frame body (frame) formed by both the section frames 16 and 16. Adjacent lead frame set 1
A series of thermal stress relaxation slits (hereinafter, referred to as end slits) 17a are formed in the front-rear direction between the section frames 16 and 16 adjacent to each other in the lengthwise direction. Further, between the adjacent section frames 16 and 16 in the lead frame set 13, a pair of thermal stress relaxation slits (hereinafter, referred to as central slits) 17b, 17b interrupted in the common frame 15 are provided in front and rear unit leads. Frame 1
It is opened to correspond to 2 and 12, respectively. The portion of the common frame 15 located at the center of the lead frame set 13, that is, both the center slits 17
In the portion where b and 17b are interrupted, the resin reservoir 18 is formed in a square planar shape having a wider plane area than the resin reservoir cavity described later by sharing four suspending members (described later) at the front, rear, left and right. Has been done. The resin reservoir 18 is provided with four circular through holes 18a arranged symmetrically in the front-rear direction and the left-right direction.

In the unit lead frame 12, the outer frame 1
4, the hanging member 1 on the common frame 15 and the section frame 16
9 are respectively formed at the corners and are integrally formed. Each of the suspension members 19 has a tab suspension lead 20.
Are integrally projected in the direction of 45 degrees. At the ends of the four tab suspension leads 20, tabs 21 formed in the shape of a square plate are suspended with their corners connected. The four tab suspension leads 20 are slightly bent in the directions opposite to each other near the base end portion and the tip end portion thereof, and the tabs 21 are lowered from the plane formed by the lead group described later by this bending. So-called tab lowering.

Dam members 22 are arranged on the parallel sides of the suspension members 19 so as to be parallel to the edges of the tabs 21 outside the tabs 21 and are integrally suspended. A plurality of leads 23 are arranged on the dam member 22 at equal intervals in the longitudinal direction, and are integrally projected so as to be parallel to each other and orthogonal to the dam member 22. The tab-side ends of the leads 23 are arranged so that their ends are close to the tabs 21 and surround the tabs 21, thereby forming the inner portions 23a. On the other hand, the extension portion of the lead 23 opposite to the tab side constitutes the outer portion 23b, and the tip end thereof is the outer frame 14,
It is substantially connected to the common frame 15 and the section frame 16. The portion between the adjacent leads 23 of the dam member 22 substantially constitutes a dam 22a that blocks the flow of the resin at the time of molding a resin-sealed package, which will be described later.

Next, the multi-row multi-row lead frame 10 having the above structure is subjected to pellet bonding work and then wire bonding work for each unit lead frame 12. By the way, during these bonding operations, the multiple multi-row lead frame 10 is pitch-fed in the row direction (left-right direction). A pair of front and rear multiple lead frames 1 of the multiple lead frame 10 are provided.
With respect to Nos. 1 and 11, the bonding tool is transported to one pitch relative to each unit lead frame at the position where the pitch feed is stopped, so that the bonding is sequentially performed for each unit lead frame 12.

Then, as shown in FIGS. 1 and 3, the pellet-bonding work causes the multi-row multi-row lead frame 10 to have a moss-type or bipolar-type integrated circuit (not shown) in the previous step. A pellet 25 as a semiconductor integrated circuit element having a built-in chip is arranged in a substantially central portion on the tab 21 of each unit lead frame 12, and a suitable pellet bonding device using a bonding material such as silver paste (see FIG. It is fixed via a bonding layer 24 formed of (not shown).

Further, between the bonding pad 25a of the pellet 25 fixedly mounted on the tab 21 and the inner portion 23a of the lead 23 in each unit lead frame 12, a wire 26 made of a copper-based material is provided between the nail heads. Wire bonding device such as ball type (not shown)
By using, the both ends are respectively bonded and bridged. This allows the pellet 2
The integrated circuit built in 5 is electrically pulled out to the outside through the bonding pad, the wire 26, the inner portion 23a and the outer portion 23b of the lead 23.

1 and 4, a resin encapsulant group for resin encapsulation for each unit lead frame is provided in the assembly 27 in which pellets and wire bonding are carried out on a multi-row multi-row lead frame, as shown in FIGS. A transfer molding device is used to simultaneously mold the unit lead frame group.

A transfer molding apparatus 30 according to an embodiment of the present invention shown in FIGS. 1 and 4 is provided with a pair of an upper die 31 and a lower die 32, and the upper die 31 and the lower die 3 are provided.
2 are attached to an upper mounting unit and a lower mounting unit that are clamped to each other by a cylinder device or the like (not shown). As shown in FIGS. 1 and 4, the upper mold cavity concave portion 33a and the lower mold cavity concave portion 33b cooperate with each other on the mating surface of the upper mold 31 and the lower mold 32 to form the cavity 33. It is respectively buried so as to form. When the resin-sealed body is transfer-molded by using the multiple-row multi-row lead frame 10 having the above-described structure, the cavities 33 in the upper die 31 and the lower die 32 include the leads in the multiple-row multi-row lead frame 10. Corresponding to the frame set 13, four sets are configured as one set. Further, the cavities 33 are arranged vertically and horizontally so as to correspond to the spaces between the pair of dam members 22 in the unit lead frame 12, respectively.

In the present embodiment, a resin reservoir cavity 40 is formed in a circular hole shape in the center of a square area formed by a set of four cavity recesses 33b on the mating surface of the lower die 32. Therefore, the depth of the resin reservoir cavity 40 is set to be shallower than the sum of the lower mold cavity recess 33a and the lower mold cavity recess 33b, that is, the height of the cavity 33. In addition, an air vent 4 having a substantially semicircular shallow groove shape is formed at the opening edge of the resin reservoir cavity 40 on the mating surface of the lower mold 32.
The pair of air vents 41, 41 are arranged so as to be symmetric with each other, and both of the air vents 41, 41 are partially opened to the resin reservoir cavity 40 so that air is evacuated from the resin reservoir cavity 40.

On the mating surface of the upper die 31, there is one pot 34 for each of the four cavities 33 corresponding to the lead frame set 13, and a pair of cavities 3 positioned in the front row of each set.
It is placed at a front position opposite to the central position between 3 and 33. A plunger 35, which is advanced and retracted by a cylinder device (not shown), is inserted into the pot 34 so that a resin (hereinafter, referred to as a resin) as a molding material can be fed. On the mating surface of the lower die 32, a cull 36 is disposed at a position facing the pot 34 and is recessed, and at the mating surface of the lower die 32, an escape recess 37 (omitted for convenience in FIG. 1). .) Is a rectangle that is slightly larger than the outer shape of the multiple-row multi-row lead frame 10 so that the lead frame can escape the thickness of the lead frame, and is buried at a constant depth of a dimension approximately equal to the thickness.

On the mating surface of the lower mold 32, a pair of runners 38 is provided to one cull 36, and the runners 38 are recessed at the front positions facing the pair of cavities 33, 33 located in the front row of each set. Are connected to the cull 36, and the other ends of both runners 38, 38 are connected to the corners of the left and right cavity recesses 33b, 33b arranged in the front row. Gates 39 are formed at the connecting portions of the runners 38 in the left and right cavity recesses 33b in the front row so that the resin can be effectively injected into the cavities.

At the diagonal position with respect to the gate 39 in each lower mold cavity recess 33b in the front row, the front side connecting passage 42 is opened in the extension direction of the diagonal so that the resin can be effectively led out from the cavity 33 in the front row. Has been done.
Each of the front side communication paths 42 is provided at a position opposite to the opening edge of the resin reservoir cavity 40 which is recessed rearward, at the air vent 41.
Are connected so as not to interfere with. Then, the front side through gate 43 is connected to the resin reservoir cavity 40 in the front side communication passage 42 connected to the resin reservoir cavity 40, and the front through gate 43 transfers the resin sent through the front side communication passage 42 to the resin reservoir cavity 40. It is formed so that it can be effectively injected into.

At the extension line positions of both front side through gates 43, 43 in the resin reservoir cavity 40,
Each rear communication path 44, 44 is opened so that the resin can be effectively extracted from the resin storage cavity 40.
Both rear side connecting paths 44, 44 are connected to the corners of the left and right lower mold cavity recesses 33b, 33b, respectively. Then, the lower mold cavity recess 33 in the rear row
A rear side through gate 45 is provided at a connection portion of the rear side communication path 44 connected to the b with the lower mold cavity recess 33b.
Cavity 3 is the resin that has been sent through the rear communication path 44.
3 is formed so that it can be effectively injected.

Next, Q which is an embodiment of the present invention when the transfer molding apparatus having the above-mentioned structure is used
A molding method for a resin-sealed package of FP / IC will be described. Here, molding of a set of four resin-sealed packages will be described.

At the time of transfer molding, as shown in FIGS. 1 and 4, the assembly 27 having the above-mentioned structure as the work of the transfer molding operation is formed by the pellets 25 and the bonding wires 26 on each unit lead frame 12. Are positioned in the respective cavity recesses 33b, the upper mold 31 and the lower mold 32 are combined and clamped by the mold opening / closing cylinder device to form the respective cavities 33. .

Subsequently, the tablets preformed with the molding material and put into the pot 34 are pushed out to the left and right runners 38, 38 by the plunger 35 advanced by the transfer cylinder device (not shown). The tablet is heated and melted by a heater (not shown) to become a liquid resin (hereinafter referred to as a resin). The resin 46 is transferred through the runners 38, 38 and injected into the left and right cavities 33, 33 in the front row from the respective gates 39.

The resin 46 injected into the left and right cavities 33, 33 in the front row is filled inside the cavities 33 along a diagonal line, and the front side connecting passage 42 opened at a diagonal position of the gate 39. Are derived from each. The resin 46 reaching each front side communication path 42 is injected into the rear resin storage cavity 40 from each through gate 43, 43.

The resin 46 injected from the left and right through gates 43, 43 into the resin reservoir cavity 40 fills the inside of the resin reservoir cavity 40 in the diagonal direction, and opens at the left and right diagonal positions, respectively. They are led out from the left and right rear connecting paths 44, respectively. The resin 46 reaching the left and right rear communication paths 44, 44 is injected from the through gates 45 into the left and right cavities 33, 33 in the rear row, respectively. The resin 46 injected into the left and right cavities 33, 33 in the rear row fills the inside of each cavity 33 along a diagonal line.

Even if there is a time difference when the resin 46 is injected into the resin reservoir cavity 40 from the left and right front through gates 43, 43, 2
Since the resin 46 from the system is filled in the resin reservoir cavity 40 at the same time, when the resin 46 is led out from the left and right rear side connecting paths 44, 44, the time difference is eliminated and the resin 46 is led out at the same time. become. As a result, when the right and left cavities 33, 33 in the rear row are respectively injected from the through gates 45, the resin 46 is simultaneously injected without a time difference, so that the molding conditions for the left and right cavities 33, 33 in the rear row are the same. And the molding condition is good.

Since the air vent 41 is provided in the resin reservoir cavity 40, voids (not shown) in the resin 46 are filled in the resin reservoir cavity 40 when the resin reservoir cavity 40 is filled. Will be effectively discharged together with the air (not shown). Therefore, in the through molding method, the cavities 33, 3 in the rear row located on the downstream side where voids are likely to occur
Also in 3, the void-free resin-sealed package is molded.

After the injection, when the resin 46 is thermally cured, the resin sealing body 28 of the package 2 is molded.
At this time, the resin sealing body 28 contracts, but since the slits 17a and 17b are provided between the unit lead frames 12, the contraction is caused by the slits 17a and 17b.
will be absorbed by b. Further, the multi-row multi-row lead frame 10 expands and contracts when heated and cooled to generate stress, and this stress also occurs in the slits 17.
absorbed by a and 17b. By the way, the central slit 1 at a position corresponding to the resin reservoir cavity 40.
Since 7b and 17b are interrupted at the position of the resin reservoir cavity 40, the resin 46 and air do not leak into the slits 17b and 17b.

Further, since the resin reservoir portion 18 of the multi-row multi-row lead frame 10 is provided with four through holes 18a, the resin 4 filled in the resin reservoir cavity 40 is formed.
6 will be filled in each through hole 18a. Therefore, the resin 46 filled in the resin reservoir cavity 40 is
The resin reservoir resin body 28A molded by
Resin portion 18 in which resin 46 filled in 8a is cured
The unit lead frame 12 is held by b. Therefore, the resin reservoir resin body 28A does not accidentally drop off from the multi-row multi-row lead frame 10.

When the resin encapsulant 28 is cured, the upper mold 31
The lower mold 32 is opened, and the resin sealing body 28 is released by the ejector pin. In this way, as shown in FIG. 5, the molded product 29 molded with the resin sealing body 28 is removed from the transfer molding device 30. The tab 21, the pellet 25, and the lead 23 are provided inside the resin sealing body 28 resin-molded in this way.
The inner portion 23a and the wire 26 are resin-sealed.

As described above, the molded product 29 on which the resin sealing body 28 has been molded is subjected to a plating process (not shown), and then a lead cutting device (not shown) is used to remove the molded product 29. Outer frame 1 sequentially for each unit lead frame
4 and the dam 22a are cut off, and the outer portion 23b of the lead 23 is gulled by a lead forming device.
The outer lead 3 is substantially molded by being bent into a wing shape. This results in Q, as shown in FIG.
The FP2 is formed and the QFP / IC1 is manufactured.

Here, the molded product 29 in which the resin encapsulant 28 is molded can be stacked to reduce the occupied area until it is cut and molded in the lead cutting and molding process after being removed from the transfer molding device. Many. At this time, in this embodiment, since the thickness of the resin reservoir cavity 40 is set to be thinner than the height of the cavity 33 for molding the resin sealing body 28, as shown in FIG. Article 29
It is possible to prevent the resin reservoir resin body 28A from interfering with the resin encapsulation body 28 when the layers are vertically stacked. As a result, it is possible to prevent the load from collapsing even when the molded products 29 are stacked in multiple stages.

According to the embodiment described above, the following effects can be obtained. (1) By filling the respective cavities in the front row with the resin in the molding process of the resin encapsulation body and then filling the respective cavities in the rear row through the common resin reservoir cavity, the cavities Even if there is a difference in resin filling time between the cavities, the resin after filling each cavity in the front row fills the common resin reservoir cavity at the same time, so the filling time difference can be eliminated once. it can. as a result,
Since the difference in resin filling time between the cavities in the rear row is prevented from occurring, it is possible to ensure the stability of the resin flow as a whole, and thus the quality and reliability of the resin encapsulant. Can be increased.

(2) In the above (1), the resin is sequentially filled in each cavity and is conveyed to the downstream side through each cavity, and each unit lead frame of the multi-row lead frame is also used. Since they are aligned next to each other in correspondence with, it is possible to reduce the amount of resin used.

(3) Further, by using the multi-row multi-row lead frame and the molding apparatus corresponding thereto,
A large number of products can be manufactured by a single molding operation, and the resin encapsulation body and cavities of the resin encapsulation package are arranged at high density, so the occupation area and material yield can be improved. It is possible to reduce the mold clamping pressure.

(4) By opening an air vent in the resin reservoir cavity, the voids in the resin are effectively discharged together with the air in the resin reservoir cavity when the resin reservoir cavity is being filled. Therefore, even in the rear row cavity located on the downstream side where voids are likely to occur in the through molding method,
A void-free resin encapsulant is molded.

(5) By forming a slit between each unit lead frame, it is possible to absorb the shrinkage of the resin encapsulant and to prevent thermal stress generated during heating and cooling of the multi-row lead frame. Can be absorbed.

(6) In the above (5), by interrupting the central slit at the position of the resin reservoir cavity, it is possible to prevent the resin and air from leaking to this slit, so that the resin sealing body It is possible to avoid secondary obstacles to the molding of the.

(7) By forming a through hole in the resin reservoir portion of the multi-row multi-row lead frame, the resin reservoir resin body molded by the resin reservoir cavity is held by the filled resin portion filled in each through hole. Therefore, it is possible to prevent the situation where the resin reservoir resin body is accidentally dropped from the assembly of the molded product.

(8) A molded product in which the resin encapsulant is molded in the multi-row lead frame by setting the thickness of the resin reservoir cavity to be thinner than the height of the cavity for molding the resin encapsulant. It is possible to prevent the resin reservoir resin body from interfering with the resin encapsulant when the products are stacked one above the other, so it is possible to prevent the load from collapsing even when the molded products are stacked in multiple stages. can do.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, the pot and cull are not limited to one for every four cavities, but may be shared by two or more cavities. Further, the upper die and the lower die are not limited to be configured to handle one assembly as a work, and may be configured to simultaneously handle a plurality of assemblies.

The gate is not limited to being opened in the lower mold, but may be opened in the upper mold. Further, the gate is not limited to being opened in only one of the upper mold and the lower mold, and both the upper mold and the lower mold are opened. May be opened in

It is desirable that the cross-sectional areas of the flow passages such as the connecting passages and the through gates be executed for each specific example of molding conditions by using an empirical method such as computer simulation or experiment.

In the above description, the invention made by the present inventor is a field of application which is the background of the invention.
The case of application to an IC has been described, but the present invention is not limited to this, and the present invention can be applied to general molding techniques for resin-sealed packages in QFJ-ICs, QFI-ICs, and other electronic devices.

[0056]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

In the case where the resin in the molding step of the resin encapsulation body is filled in each cavity in the front row and then in each cavity in the back row through the common resin reservoir cavity, the cavities in the front row should be filled. Even if there is a difference in resin filling time between the cavities, the resin after filling each cavity in the front row fills the common resin reservoir cavity at the same time, so the filling time difference can be eliminated once. it can. As a result, the difference in resin filling time between the cavities in the rear row is prevented, so that the resin flow as a whole can be stabilized, and the quality of the resin encapsulant can be ensured. And reliability can be increased.

The resin is sequentially filled in the cavities, is transported to the downstream side through the cavities, and is aligned next to each other corresponding to each unit lead frame of the multi-row lead frame. Therefore, the amount of resin used can be reduced.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing main parts of a multiple-row multi-row lead frame and a transfer molding apparatus according to an embodiment of the present invention.

FIG. 2 is a partially omitted plan view showing a multi-row multi-row lead frame that is an embodiment of the present invention.

FIG. 3 shows a state after pellet and wire bonding, (a) is a partially omitted plan view, and (b) is an enlarged sectional view taken along line bb.

FIG. 4 shows a molding process of a resin-sealed package, (a)
Is a side sectional view through the diagonal of the resin reservoir cavity,
(B) is a side sectional view passing through the front and rear cavities.

FIG. 5 is a side sectional view through a diagonal line of the resin reservoir cavity resin portion showing a resin-sealed package after molding.

6A and 6B show a QFP / IC manufactured by a manufacturing method according to an embodiment of the present invention, in which FIG. 6A is a partially cut front view and FIG. 6B is a partially cut plan view.

[Explanation of reference numerals] 1 ... QFP / IC (semiconductor device), 2 ... QFP (resin-sealed package), 3 ... Outer leads, 10 ... Multiple lead frame, 11 ... Multiple lead frame, 12 ... Unit lead frame , 13 ... Four unit lead frame groups in front, back, left and right, 14 ... Outer frame, 15 ... Common frame, 16 ... Section frame, 17a, 17b ... Thermal stress relaxation slit, 18 ... Resin reservoir, 18a ... Through hole, 18b ... Through-hole resin filling part, 1
9 ... Suspension member, 20 ... Tab suspension lead, 21 ... Tab, 2
2 ... Dam member, 22a ... Dam, 23 ... Lead, 23a ...
Inner part, 23b ... Outer part, 24 ... Bonding layer,
25 ... Pellet, 26 ... Wire, 27 ... Assembly, 28 ...
Resin sealing body, 29 ... Molded product, 30 ... Transfer molding device, 31 ... Upper mold, 32 ... Lower mold, 33 ... Cavity, 3
3a ... upper mold cavity recess, 33b ... lower mold cavity recess, 34 ... pot, 35 ... plunger, 36 ... cull, 37 ... escape recess, 38 ... runner, 39 ... gate, 4
0 ... Resin storage cavity, 41 ... Air vent, 42 ...
Front side connecting path, 43 ... Through gate, 44 ... Rear side connecting path,
45 ... through gate, 46 ... resin.

Front Page Continuation (72) Inventor Tomio Sakamoto 5-20-1 Kamimizuhoncho, Kodaira-shi, Tokyo Inside the Semiconductor Business Division, Hitachi, Ltd. (72) Inventor Yasuhiro Koyama 5-20, Kamimizumoto-cho, Kodaira, Tokyo No. 1 Incorporated company Hitachi, Ltd. Semiconductor Division (72) Inventor Takumi Soba 5-20-1 Kamimizuhonmachi, Kodaira-shi, Tokyo Within Hitachi Ltd. Semiconductor Division

Claims (7)

[Claims] 1. A semiconductor pellet in which an electronic circuit is formed, a plurality of leads electrically connected to the electronic circuit of the semiconductor pellet, the semiconductor pellet and a part of each lead are resin-sealed. In the method for manufacturing a semiconductor device, the unit group includes at least four unit lead frames each having the lead group and an outer frame that integrally supports the lead group. The unit lead frame group has two rows. A lead frame in which a multi-row multi-row lead frame is prepared in which a resin reservoir is formed in the central portion of a unit lead frame group of four pieces arranged in a grid and arranged in series. In a preparatory step, an assembly in which semiconductor pellets are bonded to the multi-row multi-row lead frame and electrically connected to each lead is formed in the resin-sealed package. The resin encapsulating body is sandwiched between molding dies and each cavity corresponding to the unit lead frame in the front row in the unit lead frame group of four pieces is filled with resin. And a molding step of filling the respective cavities corresponding to the unit lead frames of the rear row with resin through the resin reservoir cavities corresponding to the parts. 2. At least four unit lead frames each having a lead group and an outer frame for integrally supporting the lead group are provided, and the unit lead frame groups are arranged in a two-row grid pattern and continuously arranged in series. In addition, a multi-row multi-row lead frame is characterized in that a resin reservoir is formed in a central portion formed by a set of four unit lead frames. 3. The multi-row multi-row lead frame according to claim 2, wherein a through hole is opened in the resin reservoir. 4. A thermal stress relaxation slit is provided for each unit lead frame that is continuous to the left and right, and a slit located in the resin reservoir is interrupted by the resin reservoir. The multi-row multi-row lead frame according to claim 2 or claim 3. 5. At least four cavities are formed in a molding die, and the cavities are arranged in a two-row grid pattern so as to correspond to each unit lead frame of a multi-row multi-row lead frame. And the resin reservoir cavities are formed in the central portion of the cavity group of four pieces, and each of the four cavity groups is connected to the resin reservoir cavity. A molding apparatus, wherein a pair of cavities in the front row of the group of four cavities are connected to a pot. 6. The molding apparatus according to claim 5, wherein an air vent is provided in the resin reservoir cavity. 7. The molding apparatus according to claim 5, wherein the thickness of the resin reservoir cavity is set thinner than the thickness of the molding cavity.