JP2660732B2 - Semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a technology for manufacturing a semiconductor device, particularly to a technology for improving the heat radiation performance of a pellet.
The present invention relates to a device which is effective when used in a semiconductor integrated circuit device (hereinafter, referred to as an IC) which is required to have a low thermal resistance, a small size and a low price.

[Conventional technology]

Generally, ICs with large power consumption such as so-called power ICs
, A heat sink is built in a resin-sealed package. If a heat sink is incorporated into the package, the heat sink will typically be mechanically and thermally bonded to the back of the tab to which the pellet is bonded.

As an example describing a power IC having a built-in heat sink, there is P135 published by Nikkei McGraw-Hill, Inc., “Microdevices No. 2”, issued on June 11, 1984.

Japanese Patent Application Laid-Open No. Sho 54-54197 discloses a semiconductor device which does not incorporate a heat sink, but is configured to directly contact the heat sink with a tab to which a pellet is bonded.
As described in Japanese Patent Publication No. 128278, there is a resin-sealed package in which a recess is provided on one end surface so as to expose a tab.

Furthermore, high-density, high-speed ICs used in computers require high heat dissipation performance. For example, as described in JP-A-53-110371, a metal plate to which semiconductor pellets are bonded is described. There is used a ceramic package type semiconductor device in which a heat sink is externally mounted.

[Problems to be solved by the invention]

However, as mentioned above, the technology of incorporating a heat sink in the IC package is limited only to ICs with a small number of pins (leads) that have a degree of freedom in the design of the package outer shape due to the limitations of the package outer shape. That is the current situation.

The tab to which the pellet is bonded is formed integrally with the lead frame. This lead frame is required to secure the mechanical strength of the lead, and requires a spring material (iron-nickel alloy, 42 alloy, Kovar, phosphor bronze). The present inventors have clarified that there is a problem that the heat transfer efficiency is low due to the low thermal conductivity of the material due to the fact that the heat transfer is performed using the material.

On the other hand, recently, ICs are becoming more multifunctional, highly integrated, and faster,
Even for ICs with a large number of pins, there is a demand for the development of an IC with a package with a built-in heat sink that has good heat dissipation.

A first object of the present invention is to provide a semiconductor device having high heat dissipation performance.

A second object of the present invention is to provide a semiconductor device which has good productivity and mountability, can be manufactured at a low price, can promote downsizing and increase of pins, and has high heat dissipation performance. is there.

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

[Means for solving the problem]

The outline of a representative invention among the inventions disclosed in the present application will be described as follows.

That is, a semiconductor pellet in which an integrated circuit is formed on the first main surface side, a plurality of leads electrically connected to the integrated circuit of the semiconductor pellet, and a part of the semiconductor pellet and the lead are formed of resin. A semiconductor device having a package to be sealed, wherein a heat sink is joined to the first main surface of the semiconductor pellet via an insulating layer, and the heat sink is implanted in the package with a part thereof being exposed. It is.

[Action]

According to the above-described means, since the heat sink is directly in contact with the first main surface side on which the integrated circuit of the pellet is formed without passing through the tab, the heat generated by the pellet is directly transmitted to the outside through the heat sink. And sufficient heat radiation performance is secured.

In addition, since the heat sink is joined to the first main surface of the pellet by a dedicated planar structure separate from the electrical connection lead, the heat sink has good thermal conductivity separately from the electrical connection lead group. It can be configured using a suitable material. Therefore, the heat radiation performance can be further improved by selecting a material having good thermal conductivity as desired. On the other hand, since the lead group can be formed using a material having high mechanical strength, bending or breakage of the lead group can be prevented.

In addition, since the pellet, the lead group, and the heat sink are resin-sealed by the resin-sealed package, external force due to vibration during transportation when the semiconductor device is mounted on a printed wiring board or after the semiconductor device is mounted is reduced. Even in the case of joining the semiconductor device, it is possible to prevent an accident such as bending of a lead from occurring, and as a result,
Short circuit failure and disconnection failure can be prevented from occurring.

Embodiment 1 FIG. 1 is a partially cutaway front view showing a semiconductor device according to an embodiment of the present invention, and FIGS. 2 to 8 are explanatory views showing a manufacturing method thereof.

In this embodiment, a semiconductor device according to the present invention is a semiconductor integrated circuit device (hereinafter, IC) for realizing high-density mounting.
That. ) Is a resin-sealed small outline
IC with package (hereinafter referred to as SOP / IC or
Sometimes simply IC. ).
This resin-sealed SOP / IC has a silicon semiconductor pellet (hereinafter referred to as a pellet), a plurality of leads arranged around the pellet, and bonding both ends of the pellet to each electrode and each lead. The SOP / IC is provided with a bonding wire that is bridged by being bridged, a heat sink bonded to the first main surface of the pellet, and a package that seals them with a resin. Being manufactured.

Hereinafter, a method of manufacturing the resin-sealed SOP / IC will be described. From this description, the details of the configuration of the SOP / IC will be clarified.

In the present embodiment, a multiple lead frame 1 shown in FIG. 2 is used for a method of manufacturing a resin-sealed SOP / IC. The multiple lead frame 1 is formed by using a thin plate made of a spring material having relatively high mechanical strength such as an iron-nickel alloy or phosphor bronze, and by appropriate means such as punching press processing or etching processing. The multiple lead frames 1 are integrally formed, and the surface of the multiple lead frames 1 is subjected to a plating process using silver (Ag) or the like so that wire bonding described later is appropriately performed. In the multiple lead frame 1, a plurality of unit lead frames 2 are arranged in a row in the horizontal direction.

The unit lead frame 2 includes a pair of outer frames 3 each having a positioning hole 3a. The two outer frames 3 are arranged in parallel at a predetermined interval and extend in series. A pair of section frames 4 are arranged between the adjacent unit lead frames 2 and 2 in parallel with each other between the two outer frames 3 and 3 and are integrally built, and substantially formed by these outer frames and section frames. The unit lead frame 2 is formed in a rectangular frame.

In each unit lead frame 2, tab suspension leads 5 are provided at right angles on both outer frames 3, 3, and tabs 6 are integrally formed at the tips of the leads 5 into a substantially square flat plate shape. . In each unit lead frame 2,
A pair of dam members 7 are arranged inside the two section frames 4 and 4 so as to be parallel to the section frames.
It is erected integrally between them. A plurality of leads 8 for electrical connection are arranged at equal intervals in the longitudinal direction of the dam member 7, and are integrally protruded in parallel with each other and orthogonal to the dam member 7. Are arranged so that the front end surrounds a tab 6 for supporting a pellet described later, thereby forming inner portions 8a. On the other hand, the outer extension of each lead 8 has its tip connected to the section frame 4 to form an outer portion 8b. The portion between the adjacent leads 8, 8 in the dam member 7 substantially constitutes a dam 7a for damping the flow of the resin at the time of package molding described later.

This multiple lead frame 1 is subjected to a pellet bonding operation for each unit lead frame 2 and then to a wire bonding operation.
A bonding operation is performed. These bonding operations are sequentially performed for each unit lead frame 2 by feeding the multiple lead frames 1 in the horizontal direction.

Then, as shown in FIGS. 3 and 4, the pellet 11 as the semiconductor integrated circuit element in which the integrated circuit is formed in the so-called previous process in the manufacturing process of the semiconductor device is formed by the pellet bonding operation, as shown in FIGS. Each unit lead frame 2 is arranged at a substantially central portion on the tab 6 and is bonded by being mechanically fixed by a bonding layer 12 formed between the tab 6 and the pellet 11. As a means for forming the pellet bonding layer, a bonding method using a gold-silicon eutectic layer, a soldering layer, a silver paste adhesive layer, or the like can be used.

Subsequently, as shown in FIGS. 3 and 4, the electrode pads 11a of the pellets 11 bonded on the tabs 6 and the inner portions 8a of the leads 8 in each unit lead frame 2 are formed by wire bonding. The bonding wire 13 is bonded and bridged at both ends by using an appropriate wire bonding device (not shown) such as an ultrasonic thermocompression bonding wire bonding device. . This allows the pellet
The integrated circuit built in 11 is electrically led out through the electrode pad 11a, the bonding wire 13, the inner portion 8a and the outer portion 8b of the lead 8.

In this embodiment, after the wire bonding operation is completed, as shown in FIG. 6, an insulating layer 14 and a bonding layer 15 are interposed on the first main surface side on which the integrated circuit of the pellet 11 is formed. Then, the heat sink 16 configured as shown in FIG. 5 is joined.

That is, an insulating layer 14 is applied on the first main surface of the pellet 11 by using a resin or metal or the like so as to overlap with the protective film, and a bonding layer 15 is formed on the insulating layer 14 by heat conduction. And a material having good bonding properties is used for both the insulating layer 14 and the heat sink 16, and they are applied in layers. These insulating layer 14 and insulating layer 15 are
May be formed in advance in a so-called pre-process in which the semiconductor device is manufactured, or may be formed after a wire bonding operation. However, when the bonding layer 15 is formed after the wire bonding operation, it is necessary to consider the insulation between the wires 13. Therefore, in this case, the bonding layer 15 may be formed on the heat sink 16 side.

The heat sink 16 is made of a material having good heat conductivity such as copper and the like, and as shown in FIG.
It is formed in a rectangular flat plate shape larger than 11,
A joint 17 is integrally formed on the surface of the heat sink 16 to be joined to the pellet 11. The bonding portion 17 has a plane shape which is a bonding pad on the first main surface of the pellet 11.
It is formed so as to have a smaller size than the empty space surrounded by the group 11a, and so that its height can avoid interference with the wire 13. An annular groove 18 as an engagement portion is provided on the outer peripheral surface of the heat sink 16. The annular groove 18 is form-coupled to a resin sealing package described later, thereby securely fixing the heat sink 16 and providing a leak path. Is made longer. further,
Fins 19 for heat radiation are formed on the upper surface of the heat sink 16 in an uneven shape, and the fins 19 are exposed to the outside of the resin-sealed package to form a large heat radiation area of the heat sink 16, thereby increasing the heat radiation efficiency. It is becoming even higher.

The heat sink 16 thus configured is connected to its joint 17
At the first principal surface of the pellet 11. At this time, the bonding between the heat sink 16 and the pellet 11 is performed by the bonding layer 15. As the joining means, a method of welding by heating the heat sink 16 to melt the joining layer 15 or the like can be applied. Further, the heat sink 16 and the pellet 11 are electrically insulated by the insulating layer 14.

In the multiple lead frame 1 in which the heat sink is joined to the first main surface of the pellet in this way, a package group for resin sealing for each unit lead frame is formed by transfer molding as shown in FIG. The unit 30 is used to simultaneously mold the unit lead frames.

The transfer molding apparatus shown in FIG. 7 includes a pair of an upper mold 31 and a lower mold 32 which are mutually clamped by a cylinder device or the like (not shown). On the mating surface, a plurality of sets of upper mold cavity recesses 33a and lower mold cavity recesses 33b are respectively provided so as to cooperate with each other to form a cavity 33. A pot 34 is opened on the mating surface of the upper die 31, and a plunger 35 moved forward and backward by a cylinder device (not shown) is provided in the pot 34.
Are inserted so that resin (hereinafter, referred to as resin) as a molding material can be fed. On the mating surface of the lower mold 32, a cull 36 is disposed at a position facing the pot 34 and is laid down, and a plurality of runners 37 are radially disposed so as to be connected to the pot 34 and laid down. ing. The other end of each runner 37 is connected to the lower cavity recess 33b, and a gate 38 is formed at the connection so that the resin can be injected into the cavity 33. Also, on the mating surface of the lower mold 32, the escape recess 39 is a rectangle slightly larger than its outer shape, and is immersed to a certain depth of a dimension substantially equal to the thickness so that the escape recess 39 can escape the thickness of the lead frame. I have.

When a resin-sealed package is transfer-molded using the multiple lead frame according to the above configuration, each cavity 33 in the upper die 31 and the lower die 32 is formed between a pair of dam members 7 in each unit lead frame 2. Each corresponds to a space.

At the time of transfer molding, the multiple lead frame 1 according to the above configuration is provided with the relief recess 39 immersed in the lower die 32.
The pellets 11 in each unit lead frame 12 are arranged and set so as to be accommodated in the respective cavities 33. At this time, the pellet 11 and the heat sink 16
Are held in the cavity 33 while being joined to each other. Subsequently, the upper mold 31 and the lower mold 32 are clamped, and a resin 40 as a molding material is fed from the pot 34 to the respective cavities 33 through the runner 37 and the gate 38 by the plunger 35 and press-fitted.

After injection, the resin is cured by heat
When the mold 20 is formed, the upper mold 31 and the lower mold 32 are opened, and the group of packages 20 is released by ejector pins (not shown). In this manner, as shown in FIG. 8, the multiple lead frame 1 in which the packages 20 are formed is detached from the transfer forming apparatus 30.

The pellet 11, the inner portion 8a of the lead 8, the bonding wire 13, and a part of the heat sink 16 are sealed with the resin inside the resin-molded package 20. In this state, the fins 19 on the upper surface of the heat sink 16 are exposed from one end surface of the resin sealing package 20.

Thereafter, in the lead cutting and forming step, the outer frame, the section frame and each dam 7a are cut off by a lead cutting device (not shown) in the lead cutting and forming step. Equipment (not shown)
As a result, the outer portion 8b of the lead 8 is bent into a gull wing shape as shown in FIGS. 9 and 10.

The resin-sealed SOP / IC 21 manufactured as described above is mounted on a printed wiring board as shown in FIG. 9 and FIG.

In FIGS. 9 and 10, the printed wiring board 22 has a plurality of lands 23 and a resin-sealed SOP to be mounted.
・ It is arranged to correspond to each lead 8 in IC21,
It is formed in a substantially rectangular thin plate shape using a solder material. The group of leads 8 of the IC 21 is aligned and abutted on the land 23, and each lead 8 and the land 23 are formed by reflow soldering. It is electrically and mechanically connected by a solder pile layer (not shown).

Then, if necessary, the SOP / IC 21 is mounted on the printed circuit board by a heat sink 16 using a holding member (not shown).
It is held down by 22 and fixed.

In this mounting state, when the IC 21 is operated and the pellet 11 generates heat, the heat is directly conducted to the heat sink 16 from the first main surface of the pellet 11 and the heat sink 16
Since the heat is radiated to the outside air from the large surface of the pellets 16, the pellets 11 are relatively sufficiently cooled. In the case where the heat sink 16 is provided with a radiating fin, a holding member, or the like, the heat of the heat sink 16 is conducted to a wider range through the radiating fin, the holding member, or the like. Get higher.

 According to the above embodiment, the following effects can be obtained.

(1) By directly joining the heat sink to the first main surface of the pellet, heat generated on the first main surface of the pellet can be directly transmitted to the heat sink and effectively released to the outside of the package. High heat dissipation performance can be secured.

(2) Aside from the leads for electrical connection, by bonding the pellet to a heat sink formed of a material having good thermal conductivity, the heat radiation performance of (1) can be further improved.

(3) On the other hand, the lead for electrical connection is formed by using a material having high mechanical strength separately from the heat sink, whereby the lead group can be prevented from being bent or damaged. According to (2), high heat dissipation can be ensured.

(4) Since the pellet, the lead group, and a part of the heat sink are resin-sealed with a resin-sealed package, it is possible to prevent an accident such as bending of the lead, so that short-circuit failure or disconnection failure can be prevented. Occurrence can be avoided beforehand.

Embodiment 2 FIG. 11 is a partially cutaway front view showing a semiconductor device according to another embodiment of the present invention, FIG. 12 is an external perspective view thereof, and FIGS.
FIG. 17 is an explanatory view showing the manufacturing method.

In the present embodiment, the semiconductor device according to the present invention is configured as an IC (hereinafter, referred to as IC) including a surface-mounted resin-sealed package. The package of this IC is formed in a substantially square flat plate shape, and a plurality of outer portions of a lead group are protruded from near the lower end sides of four sides of the package. In this IC, the pellets are tape-automated and bonded to the leads, and heat sinks are bonded to both the front and back surfaces of the pellets. These pellets, some of the leads, and some of the heat sinks Are sealed with a resin sealing package. This IC is manufactured by the manufacturing method described below.

Hereinafter, a method of manufacturing an IC having a surface-mount type resin-sealed package according to a second embodiment of the present invention will be described. This description clarifies the details of the configuration of the IC.

In this embodiment, the IC 41 has a pellet and a lead group mechanically and electrically connected by tape automated bonding. That is, the carrier tape 42 is integrally formed using an insulating resin such as polyimide so that the same pattern is continuous in the longitudinal direction as shown in FIG. However, the description and illustration are given for only one unit. Feed holes 43 used for pitch feed are opened at equal pitches at both side edges in the width direction of the carrier tape 42, and window holes 44 are formed at equal pitches between the feed hole groups on both sides.
It is arranged and arranged in column. The window hole 44 is formed in a substantially square shape, and the size thereof is set to be sufficiently larger than the outer shapes of the pellet and the heat sink described later, and slightly larger than the length between the tips of the leads facing each other.

A plurality of leads 45 for electrically pulling out the integrated circuit to the outside are arranged on one side plane (hereinafter, referred to as a first main surface) of the carrier tape 42, and are made of a conductive material such as a copper foil. And is fixedly attached by an appropriate means such as welding or bonding. The lead 45 group is divided into four sides of the window hole 44 and disposed so as to penetrate the window hole 44 in the radial direction. The leads 45 are formed so that the leads 45 are electrically disconnected from each other. I have. Window hole at the inside tip of lead 45 group
The inner leads 46 are arranged so as to protrude into the inside 44 and to be arranged on the edge of the square, and the inner end portion forms an inner lead 46 as an inner portion. The outer tip of the lead 45 group is extended to the outside of the window hole 44 and aligned so as to be aligned on the edge of the square, and the outer lead as an outer portion is formed by a portion near the inside of the edge of the window hole 44 in each lead.
47 are configured. A test terminal portion 48 is formed on a terminal portion of each lead 45 fixed on the carrier tape 42, and a tin plating film (not shown) is formed on the surface of the lead 45 group to enhance solderability. Has been adhered.

On the other hand, although a detailed description is omitted, a desired integrated circuit is appropriately formed in a wafer state in the pellet 51 used in the IC 41 in a so-called pre-process in a semiconductor device manufacturing process. Then, the pellet 51 in which the integrated circuit (not shown) is formed is diced into small pieces of a substantially square shape slightly larger than the distance between the inner ends of the inner leads 46 facing each other. , A first main surface), a bump formed using a gold-based material
52 is a plurality, each inner lead on the carrier tape 42
It is arranged and projected to match 46.

When the pellets 51 are subjected to inner lead bonding to the leads 45, the carrier tape 42 is stretched between a plurality of sprockets (not shown) and is intermittently fed in one direction. Then, in the inner lead bonding stage provided in the middle of the stretched carrier tape 42, the pellets 51 are accommodated in the window holes 44 from below as shown in FIG. The 52 is aligned with each of the inner leads 46 and thermocompression-bonded by a bonding tool 53 to be assembled to the carrier tape 42.
That is, since a eutectic of gold-tin is formed between the tin plating film adhered to the surface of the lead 45 and the bump 52 made of a gold-based material, the inner lead 46 of the lead 45 and the bump 52 They will be joined together.

In the present embodiment, after the inner bonding operation is completed, as shown in FIG. 15, an insulating layer 54 and a bonding layer 55 are provided on the first main surface side where the integrated circuit of the pellet 51 is formed. And the heat sink 56A is joined to the second main surface via a joining layer 55A. That is, an insulating layer 54 is applied on the first main surface of the pellet 51 by using a resin or a metal so as to overlap the protective film, and a bonding layer 55 is formed on the insulating layer 54 by heat conduction. And a material having good bonding properties is used for both the insulating layer 54 and the heat sink 56, and they are overlaid. These insulating layer 54 and bonding layer 55 are pellets.
It may be formed in advance in a so-called pre-process in which the 51 is manufactured, or may be formed after the inner bonding operation. However, when the bonding layer 55 is formed after the inner bonding operation, it is necessary to consider the insulation between the leads 45. Therefore, in this case, the bonding layer 55
May be formed on the heat sink 56 side.

First heat sink bonded to the first main surface of pellet 51
56 is made of a material having good thermal conductivity such as copper,
It is formed in a square flat plate shape larger than the pellet 51, and a joint 57 is integrally formed on a joint surface of the heat sink 56 with the pellet 51. The joint 57 has a planar shape smaller than an empty space surrounded by the bumps 52 on the first main surface of the pellet 51, and its height avoids interference with the lead 45. It is formed so that it can be performed. An annular groove 58 as an engaging portion is provided on the outer peripheral surface of the heat sink 56, and the annular groove 58 is provided.
Engages with a resin-sealed package described later to securely fix the heat sink 56 and lengthen the leak path. Further, fins 59 for heat dissipation are formed on the upper surface of the heat sink 56 in an uneven shape, and the fins 59 are exposed to the outside of the resin-sealed package to form a large heat dissipation area of the heat sink 56 so that heat dissipation is achieved. Efficiency is further enhanced.

On the other hand, the second heat sink 56A joined to the second principal surface of the pellet 51 is the same as the first heat sink 56A except that the joint 57 is not provided.
The configuration is substantially the same as the structure of the heat sink 56.

Then, the first heat sink 16 configured as described above is used.
Is joined to the first main surface of the pellet 51 at the joint 17. At this time, the bonding between the heat sink 56 and the pellet 51 is performed by the bonding layer 55. As the joining means, a method in which the heat sink 56 is heated to fuse the joining layer 55 to perform welding can be applied. The insulating layer 54
Thereby, the heat sink 56 and the pellet 51 are electrically insulated. The second heat sink 56A has its fin 59
Is joined to the second main surface of the pellet on a plane opposite to the first surface. As a bonding means, a method of bonding a heat sink to a pellet by using an adhesive having good thermal conductivity for the bonding layer 55A can be applied.

In this way, the pellet 51 and the lead 45 group are tape-automated and bonded, and the carrier tape 42 in which the heat sinks 56 and 56A are respectively bonded to both surfaces of the pellet 51 is provided with an insulating material such as epoxy resin. 60 resin-sealed packages made of conductive resin
The pellets 51 are simultaneously molded using a transfer molding apparatus 70 as shown in FIG.

The transfer molding apparatus shown in FIG. 16 includes a pair of an upper mold 71 and a lower mold 72 which are mutually clamped by a cylinder device or the like (not shown). On the mating surface, a plurality of sets (only one set is shown) are recessed so that the upper mold cavity concave portion 73a and the lower mold cavity concave portion 73b cooperate with each other to form the cavity 73. I have. A pot 74 is opened on the mating surface of the upper mold 71, and a plunger 75 which is advanced and retracted by a cylinder device (not shown) feeds a resin (hereinafter, referred to as a resin) as a molding material to the pot 74. Has been inserted to get. On the mating surface of the lower mold 72, a cull 76 is disposed at a position facing the pot 74, and is submerged.
77 are arranged radially so as to be connected to the pots 74 and are submerged. The other end of each runner 77 is connected to the lower cavity recess 73b, and a gate 78 is formed at the connection so that the resin can be injected into the cavity 73. Also, on the mating surface of the upper die 71, a relief recess 79 is a rectangle slightly larger than the outer shape of the carrier tape 42 so that the escape recess 79 can escape the thickness of the carrier tape 42, and has a constant depth of a dimension substantially equal to the thickness. It has been submerged.

When transfer molding a resin-sealed package using the carrier tape 42 according to the above configuration, each cavity 73 in the upper mold 71 and the lower mold 72 is
Correspond to the space of the window hole 44 in FIG.

At the time of transfer molding, the carrier tape 42 according to the above-described configuration is set in the escape recess 79 submerged in the upper die 71 so that each pellet 51 is accommodated in each cavity 73. You. Subsequently, the upper die 71 and the lower die 72 are clamped, and the resin 80 is fed from the pot 74 to the respective cavities 73 through the runner 77 and the gate 78 by the plunger 75 and is press-fitted.

After injection, the resin is cured by heat
When the mold 60 is formed, the upper mold 71 and the lower mold 72 are opened, and the package 60 group is released by ejector pins (not shown). In this way, as shown in FIG. 17, the carrier tape 42 in which the packages 60 are formed is detached from the transfer forming apparatus 70.

The inside of the resin molded package 60 includes the pellet 51, the inner portion 46 of the lead 45 group, and the heat sinks 56 and 56A joined to the first main surface and the second main surface of the pellet 51, respectively. Part of the resin is sealed. In this state, the ends of the heat sinks 56 and 56A opposite to the pellet mounting surface are respectively exposed from the surface of the package 60, and the leads 45
The outer portion 47 of the group projects in a direction perpendicular to the side surface of the package 60.

IC molded with resin-sealed package 60 in this way
41 is shipped after undergoing an inspection such as an electrical characteristic test while being attached to the carrier tape 42.

Then, the shipped IC41 is shown in FIG. 18 in a state where it is attached to the carrier tape 42 or in a state where it is cut at an outer position of the resin-sealed package 60 and is individually separated from the carrier tape 42. As described above, the first heat sink 56 is disposed on the printed wiring board 61 with the first heat sink 56 facing upward, and the space between the outer lead 47 and the land pad 62 is subjected to reflow soldering. At this time, since the tin plating film is adhered to the surface of the lead 45, the solderability is favorably performed.

In this mounting state, when the IC 41 is operated and the pellet 51 generates heat, the heat is transferred from the pellet 51 to the heat sinks 56 and 56.
A directly conducts heat to A and heat sinks 56 and 5
Since the heat is radiated to the outside air from the large surface area of 6 A, the pellets 51 are relatively sufficiently cooled. Also, heat sink 56,
When the radiating fins and holding devices are connected to the 56A, the heat of the heat sinks 56 and 56A is transferred to a wider area through the radiating fins and holding devices, so the heat radiation effect is even higher. Become.

According to the second embodiment, the following effects can be obtained in addition to the effects of the first embodiment.

(1) By tape-automated bonding of a pellet to a lead group, a reduction in size and weight and an increase in the number of pins can be promoted, and mountability and productivity can be improved. In this case, it is also possible to reduce the price.

(2) By attaching a heat sink also to the back surface of the pellet, the heat of the pellet can be conducted directly to the heat sink on the front and back surfaces, so that the heat radiation performance can be further improved, and ICs with TAB structure etc. Also, it is possible to realize a low thermal resistance.

(3) By sealing the pellet, the lead group, and the heat sink with a resin-sealed package, a sufficiently satisfactory sealing performance can be ensured even in a semiconductor device having a TAB structure, and the outer leads are sealed with a resin. Since it can be retained by the stop package, its strength can be increased.

Although the invention made by the inventor has been specifically described based on the embodiment, the present invention is not limited to the embodiment, and it is needless to say that various modifications can be made without departing from the gist of the invention. Nor.

For example, it may be configured as shown in FIG. 19, or FIGS. 20 and 21.

In FIG. 19, instead of a second heat sink being joined to the second main surface of the pellet 51, a heat sink 56 is attached to the first main surface.
The pellet 51 bonded to the main surface is accommodated in a concave portion 64 immersed in the mounting substrate 65, and is bonded by the bonding layer 65, and each lead 47 is electrically connected to the land 66. The resin sealing package 67 is mounted on the recess 64 and the heat sink 56 by appropriate means such as potting.
It is molded to fill around.

In FIG. 20, the pellet 11 is
And the bonding pad of the pellet 11 by the wire bonding operation.
Bonding wire 1 between 11a and wiring 68 of mounting board 63
3 are bridged. Thereafter, the heat sink 16 is bonded onto the first main surface of the pellet 11 via the insulating layer 14 and the bonding layer 15, and then the resin sealing package 69 is mounted on the concave portion 64 and the heat sink 16 by appropriate means such as potting. It is molded to fill around.

In other words, the present invention is not limited to the configuration in which the heat sink is attached to the pellet after the pellet is wire-bonded or inner-bonded to the lead group. Good.

In addition, the method of attaching the heat sink to the front and back surfaces of the pellet is not limited to using a bonding method using a bonding material such as a silver paste or a solder material, but also using a fixing method using a gold-silicon eutectic layer or the like. Good.

The shape, size, structure, etc. of the heat sink correspond to various requirements such as required heat dissipation performance, mounting form (for example, whether or not holding tools and fastening bolts are used), pellet performance, size, shape, structure, etc. It is desirable to select the radiating fins, and if necessary, radiating fins, bolt insertion holes, internal threads, and the like can be provided.

The material for forming the heat sink is not limited to a copper-based material, but may be another metal material having good thermal conductivity such as an aluminum-based material. In particular, it has excellent thermal conductivity like silicon carbide (Sic),
It is desirable to use a material having a coefficient of thermal expansion substantially equal to that of silicon as a material of the pellet.

In the above description, the case where the invention made by the present inventor is mainly applied to an IC having a surface mount type resin-encapsulated package, which is a field of application in the background, has been described, but the invention is not limited thereto. The present invention can be applied to a resin-sealed power transistor and other general electronic devices. In particular, an excellent effect can be obtained when used in a semiconductor device that is small, lightweight, has many pins, is inexpensive, and requires high heat radiation performance.

〔The invention's effect〕

The effect obtained by the representative one of the inventions disclosed in the present application will be briefly described as follows.

By attaching a heat sink to the first main surface of the pellet, the heat of the pellet can be directly conducted to the heat sink, so that the heat radiation performance can be improved,
Low thermal resistance can be realized even in an IC or the like with a high degree of integration.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing a semiconductor device according to an embodiment of the present invention, FIG. 2 is a partially omitted plan view showing a multiple lead frame, and FIG. Plan view, FIG. 4 is a longitudinal sectional view of FIG. 3, FIG. 5 is a perspective view showing one embodiment of a heat sink, FIG. 6 is a longitudinal sectional view showing a heat sink bonding step, and FIG. FIG. 8 is a longitudinal sectional view showing a molding operation, FIG. 8 is a plan view showing a state after the package is molded, FIG. 9 is a perspective view showing a mounting state of the semiconductor device, and FIG. FIG. 11 is a partially cut front view showing a semiconductor device according to another embodiment of the present invention, FIG. 12 is an external perspective view thereof, FIG. 13 is a partially omitted plan view showing a carrier tape, FIG. FIG. 15 is a longitudinal sectional view showing a heat sink joining process, FIG. 16 is a partially omitted longitudinal sectional view showing a resin-sealed package molding operation, and FIG. 17 is a longitudinal sectional view showing an inner lead bonding operation. FIG. 18 is a perspective view showing a mounted state of the semiconductor device. FIG. 19 is a partially cut front view showing another embodiment of the present invention, and FIGS. 20 and 21 are longitudinal sectional views showing another embodiment of the present invention. 1 ... multiple lead frame, 2 ... unit lead frame, 3 ... outer frame, 4 ... section frame, 5 ... tab suspension lead, 6 ... tab, 7 ... dam member, 7a ... dam, 8
…… lead, 11 …… pellet, 12 …… bonding layer,
13 ... bonding wire, 14, 54 ... insulating layer, 15, 55
... joining layer, 16, 56 ... heat sink, 17, 57 ... joining part, 18, 58 ... engaging groove, 19, 59 ... fin, 20, 60, 6
7, 69: Resin-sealed package, 21: SOP / IC (semiconductor device), 22: Printed wiring board, 23: Land pad, 30, 70: Transfer molding device, 31, 71: Upper die , 32, 72… Lower mold, 33, 73… Cavity, 34, 74
…… Pot, 35, 75 …… Plunger, 36, 76 …… Cul,
37, 77 ... runner, 38, 78 ... gate, 39, 79 ... recess, 40, 80 ... resin, 41 ... IC (semiconductor device) with TAB structure, 42 ... carrier tape, 43 ... Feed hole, 44: Window hole, 45: Lead, 46: Inner lead, 47: Outer lead, 48: Test terminal, 51: Pellet, 52:
Bump, 53 ... Bonding tool, 56A ... Heat sink.

 ──────────────────────────────────────────────────の Continued on the front page (72) Kazuo Yamazaki, 111 Nishiyokote-cho, Takasaki-shi, Gunma Co., Ltd. Inside the Takasaki Plant of Hitachi, Ltd. (72) Akira Muto 111-111 Nishiyokote-cho, Takasaki-shi, Gunma, Co. Inside Hitachi, Ltd. Takasaki Plant (72) Inventor Toshiharu Takahashi 111, Nishiyokote-cho, Takasaki-shi, Gunma Co., Ltd. (72) Inventor: Masatoshi Takemura 111, Nishiyokote-cho, Takasaki City, Gunma Prefecture Takasaki Plant, Hitachi, Ltd.

Claims (3)

(57) [Claims] A semiconductor pellet having an integrated circuit formed on a first principal surface thereof, a plurality of leads electrically connected to the integrated circuit of the semiconductor pellet, and one of the semiconductor pellet and the lead. And a package for resin-sealing a portion, wherein a heat sink is joined to a first main surface of the semiconductor pellet via an insulating layer, and the heat sink is partially exposed to the package. A semiconductor device characterized by being implanted. 2. A heat sink is also joined to the second main surface of the semiconductor pellet, and the heat sink is implanted in the package with a part thereof being exposed. 2. The semiconductor device according to claim 1. 3. The semiconductor device according to claim 1, wherein said lead group is integrated by a carrier tape, and said semiconductor pellet is electrically connected to each lead by tape automated bonding. 13. The semiconductor device according to claim 1.