JPH0562980A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PURPOSE:To enable a semiconductor device to be lessened in size and thickness protecting semiconductor pellets. CONSTITUTION:In a semiconductor device 30, electrode pads 34 are formed on pellets 31 in which electronic circuits are built so as to electrically connect the electronic circuits to the outside, bumps 32 electrically and mechanically connected to a mounting board 11 are provided to the electrode pads 34 protruding, and furthermore a protective layer 41 of insulating resin is formed on all the surface of the semiconductor pellet 31 so as to enable the bumps 32 to be exposed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and a method of manufacturing the same, and more particularly to a technique for realizing small and thin mounting, for example, a semiconductor integrated circuit device (hereinafter referred to as IC) which is surface-mounted on a mounting substrate. () Related to effective technology.

[0002]

2. Description of the Related Art Generally, as a small and thin IC that is surface-mounted on a mounting board, an IC having a leadless chip carrier type package (hereinafter referred to as an LCC IC) and a tape-automated IC are provided. -There is an IC (hereinafter referred to as TAB IC) equipped with a bonding type package.

LCC / IC is a semiconductor pellet (hereinafter referred to as
It is called pellet or chip. ) Is formed on the side surface of the hermetically sealed package or the resin-sealed package in which the outer leads are intimately or substantially intimately contacted,
The outer leads are configured to be surface-mounted by being brought into contact with the lands formed on the mounting surface of the mounting substrate and being reflow-soldered. Since the outer leads are formed so as to be in close contact with the surface of the package, small and thin surface mounting can be realized.

The TAB IC is constructed as follows. A plurality of electrode pads for electrically extracting the electronic circuit to the outside are formed on the pellet in which the electronic circuit is formed, and bumps are provided on the electrode pads, respectively. On the other hand, a lead group made of copper foil is formed on the resin film. And
The pellet is electrically and mechanically connected to the inner portion of the lead group by gang-bonding the bump. Further, resin is potted on the inner portions of the pellets and the lead group, so that the resin-sealed package is formed in a small and thin shape.

In this TAB / IC, the pellets are directly bonded to the leads formed on the resin film by bumps, and the resin-sealed package is formed into a small and thin potting. , It is in a state of being formed in a small size and a thin shape as a whole. As a result, even after mounting on the mounting substrate, small and thin surface mounting can be realized.

By the way, there is a mounting technology by a flip chip method as a technology for mounting an IC on a mounting substrate in a small and thin form and at a high density. What is the flip chip method?
It is a name given by so-called face-down bonding, in which the chip is turned upside down and bonding is performed using the connection terminals formed on the surface or the mounting substrate. The flip chip method includes a ball method in which a metal ball is attached to a chip, a bump method in which a protruding electrode is formed of aluminum or a silver alloy, or a pedestal method in which a pedestal is attached to a mounting substrate, depending on the form of the connection terminal to be formed.

The ball-type flip-chip structure is characterized in that a considerably thick low-melting glass is used as a chip protective film and that bumps for electrode connection (protruding electrodes, Bum) are used.
p) is formed from a solder (Pb-Sn) which covers the surface of a Cu ball plated with Ni and Au. In the manufacturing method, first, the surface of a conventional planar element having an Al electrode is covered with protective glass. Next, the glass film of the electrode portion is removed, an electrode base is formed of a multi-layer metal of Cr-Cu-Au, and Cu balls plated with Ni and Au are placed on the electrode base to form bumps welded by solder. This method is not suitable for a chip having a large number of electrodes because it is connected via Cu balls.

Therefore, as an improved form of this system, there is a controlled collapse reflow bonding system (hereinafter referred to as CCB). This is one in which hemispherical bumps are formed by using Sn-Pb instead of the ball type Cu balls. The bump is a barrier metal (Cr
-Cu-Au) on the Al pad. In order to prevent excessive solder flow during bonding, a chip having a pad that is not connected to internal wiring has been devised.

Flip chips made of Al or Ag-Sn bumps are easy to work with Al and Ag alloys.
It is used because it is easy to obtain bonding conditions. The manufacturing method is the same as the above-mentioned ball method until the wafer having the internal wiring is covered with the glass film or the SiO ₂ film and the window for the electrode is opened by the photoresist technique. next,
After thinly depositing Cr or Ti as an adhesive metal,
The bump metal is attached and the bump portion is left to be removed by etching. The adhesion thickness of the bump metal is determined by the balance between the etching yield and the bondability, and is generally about 25 μm. Also, the size of the bump is limited by the chip size. There is also a flip chip using solder instead of Al and Ag—Sn.

As an example in which the package technology is described, there is "IC mounting technology" issued by Industrial Research Institute Co., Ltd., issued January 15, 1980, P135-P150.

As an example in which the flip chip technology is described, "IC mounting technology" issued by the Industrial Research Institute Co., Ltd.
Published January 15, 1980 P81, P103 to P10
There are five.

[0012]

[Problems to be Solved by the Invention] However, LCC / IC
In TAB and IC, since leads are interposed between the pellet and the mounting substrate, there is a limit in promoting miniaturization and thinning.

On the other hand, in the mounting technology by the flip chip method, since the pellet is mounted on the mounting substrate as it is, the pellet is damaged depending on the handling at the time of mounting, and the quality and reliability of mounting are deteriorated. There is a point.

The object of the present invention is to protect pellets while
It is an object of the present invention to provide a semiconductor device capable of promoting miniaturization and thinning and a manufacturing method thereof.

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.

[0016]

The typical ones of the inventions disclosed in the present application will be outlined below.

That is, a plurality of electrode pads for electrically pulling out the electronic circuit to the outside are formed on a semiconductor pellet in which the electronic circuit is formed, and each electrode pad is electrically and mechanically mounted on the mounting substrate. Bumps that are electrically connected to each other are projected, and a protective layer made of an insulating resin is exposed on at least the main surface of the semiconductor pellet on which the electrode pad group is formed. It is characterized in that it is formed as follows.

[0018]

According to the above-described means, since the protective layer made of resin having an insulating property is formed so as to expose each bump, on the main surface of the semiconductor pellet on which at least the electrode pad group is formed, The pellet will be sufficiently protected by the protective layer made of resin.

On the other hand, since the semiconductor pellets are mechanically and electrically directly connected to each other by bonding the bumps to the mounting substrate, the mounting state of the semiconductor pellet becomes extremely small and thin.

[0020]

1 is a partially omitted enlarged front sectional view showing a semiconductor device according to an embodiment of the present invention, FIG. 2 is a perspective view thereof, and FIG.
Is a partially omitted front sectional view showing a mounting state on the mounting board, FIG. 4 is a partially omitted perspective view showing a mounting board used therein, FIG. 5 is a partially omitted front sectional view, FIG. 6 and FIG. 7A to 7C are front cross-sectional views showing steps of forming a protective layer in a method for manufacturing a semiconductor device according to an embodiment of the present invention.

In the semiconductor device 30 according to the present embodiment of the present invention, a semiconductor pellet (hereinafter referred to as pellet) 31 in which an integrated circuit is formed is a computer module substrate (hereinafter referred to as substrate) 11 as a mounting substrate. In addition, the plurality of connection terminals 23 formed by the CCB method are configured to be mechanically and electrically connected. The greatest feature of the semiconductor device 30 is that a plurality of electrode pads 34 for electrically pulling out the integrated circuit are formed on a pellet 31 in which an integrated circuit (not shown) as an electronic circuit is formed. In addition, each electrode pad 34 is provided with a bump 32 electrically and mechanically connected to the mounting substrate 11, and the entire surface of the pellet 31 is protected by an insulating resin. The layer 41 is formed so that each of the bumps 32 is exposed.

Before describing the semiconductor device and the method of manufacturing the same according to this embodiment, the structure of the substrate 11 on which the semiconductor device is mounted will be described.

As shown in FIGS. 4 and 5, the substrate 11 comprises a base 12 formed of alumina ceramic, the base 12 having a suitable strength so that it can be used as a computer module substrate. And a square board shape having a size. In the present embodiment, alumina ceramic is used as the constituent material of the base 12, but not limited to this, it is possible to use insulating materials such as silicon carbide, ceramics such as mullite and aluminum nitride, and epoxy resin. You can

A first insulating layer 13 is laminated on the base 12, and the first insulating layer 13 is formed in a film shape using a polyimide resin. This first insulating layer 1
A first electric wiring (hereinafter, referred to as a first wiring) 14 is provided on the surface 3.
Are patterned into a desired shape and wired. In the present embodiment, the first wiring 14 is formed by joining a copper foil on the first insulating layer 13 using titanium as an adhesion metal and selectively patterning it by a lithography process.

The second insulating layer 1 is formed on the first insulating layer 13.
5 is laminated, and the second insulating layer 15 is formed in a film shape using a polyimide resin similarly to the first insulating layer 13. A second electric wiring (hereinafter referred to as a second wiring) 16 is patterned and wired in a desired shape on the second insulating layer 15. The second wiring 16 is
It is formed similarly to the first wiring 14.

Further, a plurality of through holes 17 are formed in the second insulating layer 15 by a lithographic process, and each through hole 17 exposes a predetermined electrode portion of the first wiring 14. .. The through-hole conductor 18 is made of the same conductive material as that of the first wiring 14 for each through-hole 17, and a vapor deposition method, a sputtering method,
It is filled by an appropriate means such as a plating method. Then, each through-hole conductor 18 is in a state where one end (hereinafter, referred to as a lower end) is electrically connected to each electrode portion of the first wiring 14 and an upper end thereof is the second insulating layer 1.
5 is exposed.

As shown in FIG. 5, the second insulating layer 1
5, a protective insulating layer 19 is laminated, and the protective insulating layer 19 is made relatively thick by using a polyimide resin which is an example of an insulating material having a small lateral elastic modulus.

The protective insulating layer 19 has a second through hole 2
A plurality of 0s are formed by a lithography process, and each second through hole 20 exposes each through hole conductor 18 of the first wiring 14 and a predetermined electrode portion of the second wiring 16. ing. The second through-hole conductors 21 are filled with the second through-hole conductors 21 by using the same material as that of the wirings 14 and 16 by an appropriate means such as a vapor deposition method, a sputtering method or a plating method. The lower ends of the through-hole conductors 21 are electrically connected to the first through-hole conductors 18 and the electrodes of the second wiring 16, respectively, and the upper ends thereof are exposed on the protective insulating layer 19. It is in a state of being.

CCB pads 22 are formed on the upper ends of the respective second through-hole conductors 21. The pad 22 is formed also as a preliminary solder so that the bump described later has good wettability with the solder of the main body. And each pad 22 is a pellet 3
The bumps 32 in FIG. 1 are arranged so as to correspond to each bump 32, and the arrangement groups are arranged by the number of pellets 31 mounted on the substrate 11.

Next, the semiconductor device 30 according to the present embodiment is
It is manufactured by the following manufacturing method. Hereinafter, a method of manufacturing this semiconductor device will be described. This description clarifies the details of the configuration of the semiconductor device 30.

In this embodiment, the pellet 31 shown in FIGS. 1 and 2 is manufactured. Bumps 3 for forming the connection terminals 23 on the connection-side main surface of the pellet 31.
A plurality of 2 are formed at predetermined intervals. The manufacturing work of the pellets 31 and the bumps 32 is performed in the form of a wafer in a so-called pre-process in the manufacturing process of the semiconductor device. Hereinafter, the manufacturing process of the pellets 31 will be briefly described with a focus on the bump 32 forming process.

In a so-called pre-process of manufacturing a semiconductor device, a desired integrated circuit (not shown) is formed in a wafer form so as to correspond to each pellet 31. Next, in the electric wiring forming step, the electric wiring 34 is formed on the insulating film 33 of the integrated circuit. Aluminum is used for the work of forming the electric wiring 34, and the work is performed by an appropriate thin film forming process such as sputtering or vapor deposition and a lithographic process. A passivation film 35 is deposited on the electric wiring 34. Usually, the passivation film 35 is composed of a hard insulating film such as a silicon oxide film or a silicon nitride film.

The passivation film 35 has a plurality of through holes 36 (eight in this embodiment), which are spaced from each other in the outer peripheral portion of the pellet 31, as shown in FIG. They are arranged in predetermined places and opened respectively. Predetermined electric wiring 34 is exposed on the bottom surface of each opened through hole 36. The operation of opening the through hole 36 is selectively performed by a lithography process.

Thereafter, in the bump forming step, a suitable thin film forming process such as vapor deposition or sputtering and a lithographic process are used to electrically connect the bump 32 to each electric wiring 34 in each through hole 36 of the pellet 31. To be formed respectively. For example, the bump 32 includes a first underlayer 37 made of chromium, a second underlayer 38 made of copper, a third underlayer 39 made of gold, and a solder (Sn).
-Pb) and a main body 40.

As described above, the wafer on which the pellets 31 and the bumps 32 are formed is divided into the pellets 31 in the dicing process. The pellet 31 after being diced is formed into a substantially square minute flat plate shape corresponding to the pellet mounting region on the substrate 21 described above.

Thereafter, as shown in FIGS. 6 and 7, in the potting process, a holding layer 41 is formed on the entire surface of the diced pellet 31, and each bump 32 is formed.
Are formed to be exposed. That is, FIG.
Further, as shown in FIG. 7, the potting resin 42 made of a resin having an insulating property is stored in the processing tank 43. As the potting resin 42, for example, a thermoplastic epoxy resin is used, and is stored as a liquid having a predetermined viscosity in the processing tank 43.

Then, as shown in FIG. 6, the pellet 31 is transported to the processing tank 43 by the handler 45 and immersed in the potting resin 42 while being held by vacuum suction by the processing jig 44. At this time, the processing jig 4
Since the bumps 32 are suction-held by the nozzles 4, the bumps 32 are masked by the processing jig 44.

As shown in FIG. 7, the pellet 31
When is removed from the potting resin 42, the liquid potting resin 42 is in an adhered state on the entire surface of the pellet 31 except for the masked bumps 32. Then, when the potting resin 42 is cured, a protective tank 41 made of the potting resin 42 is formed on the entire surface of the pellet 31 with each bump 32 exposed.

Although one pellet 31 is handled (not shown) in FIGS. 6 and 7,
The plurality of pellets 31 can be configured to be potted together.

The semiconductor device 30 according to this embodiment manufactured as described above has the CCB on the substrate 11 having the above-described structure.
Gang bonding is performed for each group of pads 22 by the method. That is, the semiconductor device 30 is aligned with each pad 22 group row of the substrate 11 and is temporarily bonded in a face-down state in which the bumps 32 are fitted to the pads 22 subjected to the preliminary soldering process.

Thereafter, the solder body 40 of each bump 32 is melted by an appropriate reflow soldering process, so that each connection terminal 23 is simultaneously formed as shown in FIG. The semiconductor device 30 is mechanically connected to the substrate 11 by the group of connection terminals 23, and the integrated circuit of the semiconductor device 30 is connected to the first wiring 14 and the second wiring via the connection terminals 23 and the through-hole conductors 21 and 18. 16 is electrically connected. In this way, the mounting body 10 in which the semiconductor device 30 is mounted on the substrate 11 is manufactured.

According to the above embodiment, the following effects can be obtained.
In the semiconductor device 30, the protective layer 41 made of a resin having an insulating property is formed on the entire surface of the pellet 31 for each bump 32.
Therefore, the pellet 31 is sufficiently protected by the protective layer 41.

The pellet 31 is sufficiently protected by the protective layer 41 so that the substrate 11 can be formed by the CCB method.
Since it is possible to prevent the pellets 31 from being damaged when they are mounted on or when they are handled with respect to other pellets 31, the yield of the semiconductor devices 30 can be improved, and the quality and reliability thereof can be improved. Can be increased.

On the other hand, since the pellets 31 are mechanically and electrically directly connected by the CCBs of the bumps 32 on the mounting substrate 11, the mounting state thereof is extremely small and thin.

In the semiconductor device 30, the pellet 3
Since the entire surface of No. 1 is surrounded by the protective layer 41 made of resin, the mechanical strength of the pellet 31 is enhanced and the electrical insulation is enhanced.

By arranging the bumps 32 on the outer peripheral portion of the pellet 31, it is possible to visually inspect all the states of the connection terminals 23 formed by the CCB method. The reliability can be increased.

FIG. 8 is an enlarged front sectional view showing a semiconductor device according to another embodiment of the present invention, and FIG. 9 and subsequent drawings are explanatory views showing a method for manufacturing a semiconductor device according to another embodiment of the present invention.

The semiconductor device 30A according to the second embodiment differs from the semiconductor device 30 according to the first embodiment in that a protective layer 41A made of an insulating resin is formed by a transfer molding method, and pellets are formed. The heat sink 50 is bonded to the main surface of the electrode 31 opposite to the main surface on which the electrode pad 34 is arranged, and one main surface of the heat sink 50 is exposed to the outside from the protective layer 41A. ..

Next, a method for mounting the heat sink 50 and a transfer molding method for the protective layer 41A will be described. Based on this description, the semiconductor device 30 according to the second embodiment.
Details of the configuration of A are revealed.

In the second embodiment, in the method of manufacturing the semiconductor device 30A, a multiple lead frame (hereinafter referred to as a dedicated multiple lead frame) 51 as a heat sink dedicated planar structure shown in FIG. 9 is used. It is used.
This dedicated multiple lead frame 51 is integrally formed by a suitable means such as punching press working or etching using a thin plate made of a material having relatively good thermal conductivity such as copper (Cu). In this dedicated multiple lead frame 51, a unit lead frame dedicated to a heat sink (hereinafter referred to as a dedicated unit lead frame) 5
2 are arranged in a line in one direction.

The dedicated unit lead frame 52 is provided with a pair of outer frames 53 having positioning holes 53a, and both outer frames 53 are extended in series. A pair of section frames 54 are arranged between the outer frames 53, 53 in parallel with each other between the dedicated unit lead frames 52, 52 adjacent to each other, and are integrally constructed. The dedicated unit lead frame 52 is formed in a substantially rectangular frame body.

In each dedicated unit lead frame 52,
A heat sink suspending member 55 is arranged at each corner portion of the outer frame 53 section frame 54 and integrally protrudes inwardly in a direction of approximately 45 degrees. A heat sink is provided between the tip ends of the heat sink suspending members 55. 50 is bridged and suspended.

The heat sink 50 is formed to be larger than the planar shape of the pellet 31.
A plurality of cutout portions 56 are provided on the outer periphery of the, and are arranged radially inward at substantially equal intervals in the circumferential direction. The cutouts 56 are configured to formally bond the protective layer 41A to the pellet 31 after the protective layer 41A, which will be described later, is formed.

The pellet-bonding work is carried out for each dedicated unit lead frame 52 on the dedicated multiple lead frame 51 thus constructed. This pellet bonding work is sequentially performed for each dedicated unit lead frame 52 by feeding the dedicated multiple lead frames 51 in the lateral direction with a pitch.

Then, as shown in FIG. 10, the pellet 31 manufactured in the same manner as in the first embodiment is concentrically formed on the heat sink 50 of each dedicated unit lead frame 52 by the pellet bonding operation. It is arranged and bonded by being mechanically fixed by a bonding layer 57 formed between the heat sink 50 and the pellet 31. As a means for forming the pellet bonding layer 57, a bonding method using a gold-silicon eutectic layer, a soldering layer, a silver paste adhesive layer, etc. can be used. However, it is desirable to form the bonding layer 57 so as not to act as a barrier for heat transfer from the pellet to the heat sink, if necessary.

For the dedicated multiple lead frame 51 thus pellet-bonded, the protective layer 41A group is used for each unit lead frame 52, and the transfer molding device 60 as shown in FIG. 11 is used. The unit lead frame group is simultaneously molded.

The transfer molding apparatus shown in FIG. 11 includes a pair of upper mold 61 and lower mold 62 which are clamped together by a cylinder device or the like (not shown). A plurality of sets of cavities 63 are sunk in the mating surface with. A plurality of recesses 70 are formed on the bottom surface of the cavity 63 so as to correspond to the bumps 32 of the pellet 31, respectively. A pot 64 is provided on the mating surface of the upper die 61, and a plunger 65 that is moved forward and backward by a cylinder device (not shown) is provided in the pot 64 as an epoxy resin (hereinafter referred to as a resin) as a molding material. ) Has been inserted so that it can be sent.

On the mating surface of the lower mold 62, a cull 66 is arranged at a position facing the pot 64 and is sunk.
A plurality of runners 67 are radially arranged so as to be connected to the pots 64 and are recessed. The other end of each runner 67 is connected to the cavity 63,
A gate 68 is formed at a connection portion of the cavity 63 with the runner 67 so that a resin can be injected into the cavity 63. Further, in order to allow the escape recess 69 to escape the thickness of the dedicated multiple lead frame 51 on the mating surface of the lower mold 62, it is a rectangle slightly larger than its outer shape, and has a constant depth of a dimension substantially equal to the thickness thereof. It is buried.

When the protective multiple layer lead frame 51 having the above structure is used to transfer-mold the protective layer 41A, the opening edges of the cavities 63 in the lower mold 62 are the outer frame 53 of each dedicated unit lead frame 52 and The sections correspond to the inner and outer sides of the section frame 54.

At the time of transfer molding, the dedicated multiple lead frame 51 according to the above-described structure is placed in the escape recess 69 which is recessed in the lower die 62, and the pellet 31 of each dedicated unit lead frame 52 is placed in each cavity 63. It is arranged and set so as to be housed in each. At this time, the pellet 31 is held in the cavity 33 while being bonded to the heat sink 50. The bumps 32 of the pellet 31 are housed in the recesses 70 that are recessed in the bottom surface of the cavity 63.

Subsequently, the upper die 61 and the lower die 62 are clamped, and the resin 71 as a molding material is fed from the pot 64 to the respective cavities 63 through the runner 67 and the gate 68 by the plunger 65 and press-fitted. ..

After the injection, the resin is heat-cured to protect the protective layer 41.
When A is molded so as to entirely surround the pellet 31, the upper mold 61 and the lower mold 62 are opened, and
The ejector pins (not shown) release the protective layer 41A group. In this manner, the dedicated multiple lead frame 51 in which the protective layer 41A is formed on substantially the entire surface of the pellet 31.
Is removed from the transfer molding device 60.

The pellet 31 is resin-sealed inside the protective layer 41A thus resin-molded. In this state, one end surface of the heat sink 50 is exposed from the main surface of the protective layer 41A opposite to the bump 32 group. Further, at a position corresponding to each bump 32, a convex portion 75 is formed by each concave portion 70 that is recessed in the bottom surface of the cavity 63.

Thereafter, in the bump repairing process shown in FIGS. 12 and 13, the protective layer 41A is subjected to an etching process and a thick film forming process. That is, first, as shown in FIG. 12, the masking jig 73 is brought into contact with the bump-side main surface of the protective layer 41. At this time, the convex portion 72 formed by the concave portion 70 corresponding to each bump 32 has the window hole 74 formed in the masking jig 73.
The projection 72 is exposed through the window hole 74. By fitting the convex portion 72 and the window hole 74, the masking jig 73 and each protective layer 41A are positioned relative to each other.

Then, the etching treatment liquid is brought into contact with the main surface of the protective layer 41A masked by the masking jig 73 except for the convex portions 72 by an appropriate means such as a spray method or a dipping method. As the etching liquid, a liquid capable of etching an epoxy resin such as fuming nitric acid is used. By this etching process, the convex portion 72 of the protective layer 41A is removed, and the periphery of each bump 32 is removed, so that each bump 32 becomes a protective layer 4.
Each is exposed from the main surface of 1A.

Thereafter, as shown in FIG. 13, a main body 4 made of a solder material for each bump 32 is formed by an appropriate selective thick film forming means such as a screen printing method or a spray printing method.
0 is replenished with the solder material layer 75. This solder material layer 7
By replenishing each of the bumps 5, the bumps 32 are appropriately projected from the upper surface of the protective layer 41A.

As described above, the dedicated multiple lead frame 51 in which the protective layer 41A is transfer-molded on the surface of the pellet 31 and the bumps 32 are corrected is sequentially manufactured for each unit lead frame 52 in the lead cutting molding process. ,
The outer frame 53, the section frame 54, and the heat sink suspension member 55 are cut off by a lead cutting device (not shown). In this way, the semiconductor device 30A shown in FIG. 8 is manufactured.

The semiconductor device 3 manufactured as described above
0A is mounted on the substrate 11 as in the first embodiment.
In this case, if necessary, a radiation fin (not shown) is attached to the heat sink 50 of the semiconductor device 30A, or the heat sink 50 is pressed and fixed to the substrate 11 by a pressing tool (not shown). ..

In this mounted state, the semiconductor device 30A
When the pellets 31 are operated and the pellets 31 generate heat, the generated heat is directly conducted from the pellets 31 to the heat sink 50 and is radiated to the outside air from the large surface area of the heat sink 50. To be cooled. In addition, when the heat sink 50 is provided with a radiation fin, a retainer, etc., the heat of the heat sink 50 is conducted to a wider range through the heat radiation fin, the retainer, etc., so that the heat dissipation effect is further enhanced. Get higher

According to the second embodiment, the following effects can be obtained in addition to the effects of the first embodiment. By directly bonding the heat sink 50 to the pellet 31, the heat generated in the pellet 31 can be effectively propagated to the heat sink 50 by heat conduction and can be effectively released to the outside of the protective layer 41A. Can be secured.

By molding the protective layer 41A by the transfer molding method, the protective layer 41A can be densely and strongly constructed, so that the mechanical strength and the electrical insulating property can be enhanced and the moisture resistance can be enhanced. be able to.

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

For example, the protective layers 41 and 41A are not limited to be formed so as to surround the entire surface of the pellet, but may be formed so as to cover at least the main surface of the pellet on which the bump group is formed. Alternatively, the protective layer may be formed so as to cover the surface other than the main surface on which the bump group is formed.

Further, the bump is not limited to be formed by using a solder material, but can be formed by using aluminum, silver or gold, or any other conductive and heat-soluble material.

Further, the bumps can be arranged not only in the peripheral portion of the pellet but also in the central portion.

The material for forming the electric wiring and the through-hole conductor is not limited to copper, but aluminum or the like may be used, and titanium is used as the material for forming the adhesive metal layer. Not limited to this, chrome or the like may be used.

The electric wiring layer is not limited to two layers,
It may be formed in one layer, or may be formed in three or more layers.

The method of flip-chip bonding the pellet to the substrate is not limited to the CCB method, but another flip-chip method may be used.

In the above description, the case where the invention made by the present inventor is mainly applied to the semiconductor integrated circuit device used for the module of the computer which is the background field of application has been described, but the invention is not limited thereto. Instead, it can be applied to all semiconductor devices such as transistors, diodes, and semiconductor circuit devices in which pellets are bonded to a substrate by a flip chip method.
In particular, the present invention is applied when the pellet size is large, and excellent effects can be obtained.

[0080]

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

Since at least the main surface of the semiconductor pellet on which the electrode pad group is formed is formed with a protective layer made of an insulating resin so that each bump is exposed, the semiconductor pellet is sufficiently protected by the protective layer. Will be protected.

On the other hand, since the semiconductor pellet is mechanically and electrically directly connected by bonding each bump to the mounting substrate, the mounting state becomes small and thin.

[Brief description of drawings]

FIG. 1 is an enlarged front sectional view showing a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a perspective view thereof.

FIG. 3 is a partially omitted front sectional view showing a mounting state on the mounting board.

FIG. 4 is a partially cutaway perspective view showing a mounting substrate used therein.

FIG. 5 is a partially omitted front cross-sectional view thereof.

FIG. 6 is a front cross-sectional view showing the potting process in the protective layer forming step in the method for manufacturing a semiconductor device which is an embodiment of the present invention.

FIG. 7 is a front sectional view showing the state after potting in the protective layer forming step in the method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIG. 8 is an enlarged front sectional view showing a semiconductor device according to another embodiment of the present invention.

FIG. 9 is a partially omitted plan view showing a heat sink dedicated multiple lead frame used in a method of manufacturing a semiconductor device according to another embodiment of the present invention.

FIG. 10 is a front sectional view showing the state after the pellet bonding.

FIG. 11 is a partially omitted front sectional view showing a transfer molding step of the protective layer.

FIG. 12 is a partially omitted front sectional view showing the bump exposing process.

FIG. 13 is a partially omitted front cross-sectional view showing the bump correction process.

[Explanation of sign]

11 ... Substrate, 12 ... Base, 13 ... First insulating layer, 14 ...
First electric wiring (first wiring), 15 ... Second insulating layer, 16 ...
2nd electric wiring (2nd wiring), 17 ... through hole, 18
... through-hole conductor, 19 ... protective insulating layer, 20 ... second through-hole, 21 ... through-hole conductor, 22 ... pad, 23 ... connection terminal, 30 ... semiconductor device, 31 ... pellet, 32 ... bump, 33 ... insulation Membrane, 34 ... Electrical wiring, 3
5 ... Passivation film, 36 ... Through hole, 37 ...
First underlayer, 38 ... Second underlayer, 39 ... Third underlayer, 4
0 ... Main body, 41, 41A ... Protective layer, 42 ... Potting resin, 43 ... Potting treatment tank, 44 ... Treatment jig, 4
5 ... Handler, 50 ... Heat sink, 51 ... Heat sink dedicated multiple lead frame, 52 ... Dedicated unit lead frame, 53 ... Outer frame, 54 ... Section frame, 55 ... Heat sink hanging member, 56 ... Notch portion, 57 ... Bonding layer, 60 ... Transfer molding device, 61 ... Upper mold, 62 ...
Lower mold, 63 ... Cavity, 64 ... Pot, 65 ... Plunger, 66 ... Cull, 67 ... Runner, 68 ... Gate, 6
9 ... Recess, 70 ... Recess, 71 ... Resin, 72 ... Convex, 7
3 ... Masking jig, 74 ... Window hole, 75 ... Solder material layer.

Claims (6)

[Claims] 1. A semiconductor pellet having an electronic circuit formed therein is formed with a plurality of electrode pads for electrically drawing the electronic circuit to the outside, and each electrode pad is electrically and mechanically mounted on a mounting substrate. Bumps that are electrically connected to each other are projected, and a protective layer made of an insulating resin is exposed on at least the main surface of the semiconductor pellet on which the electrode pad group is formed. A semiconductor device characterized by being formed as described above. 2. The semiconductor device according to claim 1, wherein the electrode pad group is arranged on the outer peripheral portion of the semiconductor pellet, respectively. 3. The semiconductor device according to claim 1, wherein a heat sink is bonded to at least a part of the semiconductor pellet, and the heat sink is exposed to the outside from the protective layer. .. 4. A step of forming an electronic circuit on a semiconductor pellet, a step of forming a plurality of electrode pads on the semiconductor pellet for electrically drawing the electronic circuit to the outside, and a step of mounting each electrode pad on a mounting substrate. A step of providing bumps that are electrically and mechanically connected to each other, and a protective layer made of an insulative resin is formed on the main surface of the semiconductor pellet on which at least the electrode pad group is formed. And a step of forming so as to expose the semiconductor device. 5. The method of manufacturing a semiconductor device according to claim 4, wherein the step of forming the protective layer is configured to be performed by a potting method. 6. The method for manufacturing a semiconductor device according to claim 4, wherein the step of forming the protective layer is configured to be performed by a transfer molding method.