JP2907187B2 - Bare chip mounting method and semiconductor integrated circuit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a bare chip mounting method for flip-chip mounting a semiconductor bare chip and a semiconductor integrated circuit device manufactured by using the bare chip mounting method.

[0002]

2. Description of the Related Art FIG. 3 illustrates a conventional method of mounting a bare chip. The semiconductor bare chip 11 is mounted on a dielectric substrate 13 with an electrically insulating resin 12. The bumps 14 as fine solder terminals formed on the pads of the semiconductor bare chip are connected to the corresponding portions of the dielectric substrate 13 in this state.

[0003] With the increase in the speed of circuit operation and the improvement of circuit functions of a semiconductor integrated circuit device, the degree of integration of the circuit device is further increased, and power consumption and heat generation are further increasing.
In the bare chip mounting method shown in FIG. 3, heat generated on the semiconductor bare chip 11 is transmitted to the dielectric substrate 13 via only the bumps 14. Therefore, there arises a problem that sufficient heat radiation characteristics cannot be obtained.

FIG. 4 illustrates a bare chip mounting method proposed to solve such a problem. In this method, the frame-shaped member 2
2 is fixed by silver brazing or the like so as to form a cavity-like space. The integrated circuit chip 25 to which the heat radiation stud 23 is fixed by the joining member 24 is connected to the wiring board 21 via the solder bump 26. The space between the frame-shaped member 22 and the heat radiation stud 23 is filled with an electric insulating resin 27 for sealing so as to completely cover the surfaces of the integrated circuit chip 25 and the wiring board 21. On the upper part of the electrically insulating resin 27, a coating of a low melting point metal 28 is formed.

Here, the electric signal of the integrated circuit chip 25 is guided to the outside of the chip carrier through the solder bump 26 and the through hole 31 inside the wiring board 21, and is connected to the wiring board 33 by the solder joint 32. It has become. Further, heat generated in the integrated circuit chip 25 is absorbed by a heat sink (not shown) fixed or pressed against the heat sink via the heat radiation stud 23.

[0006]

According to the bare chip mounting method shown in FIG. 3 or FIG. 4 or the semiconductor integrated circuit device manufactured by this method, a semiconductor bare chip,
That is, good heat radiation characteristics cannot be obtained only by mounting the integrated circuit chip 25. This is because, as described with reference to FIG. 3, only the semiconductor bare chip has a heat radiation path of only the solder bump 26. Therefore, it has been proposed to use a heat radiating stud 23 on the back surface of the integrated circuit chip 25 and attach a heat radiating material thereto, as shown in FIG.
However, in this method, since the heat dissipating material such as the heat dissipating stud 23 and the heat sink is mounted on the semiconductor bare chip so as to overlap, there is a problem that the height of the entire module is bulky.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a bare chip mounting method capable of providing good heat radiation characteristics without attaching a heat radiating material to the back surface of a semiconductor bare chip, and a semiconductor integrated circuit device using this method.

[0008]

According to the first aspect of the present invention, there is provided a semiconductor device having the same thickness as a semiconductor bare chip so as to surround only a side surface of the flat semiconductor bare chip.
Apply a good heat conductive adhesive to the extended position of the bare chip.
(B) flip chip mounting of a bare semiconductor chip on a dielectric substrate such that a material having good heat conductivity is interposed between the first step of attaching a frame member having good heat conductivity through the first step; And the second step to be performed are provided in the bare chip mounting method.

That is, according to the first aspect of the present invention, only the side surface of the semiconductor bare chip is interposed with a good heat conductive adhesive.
In the first step, a frame member having good heat conductivity is attached, and in the second step, a material having good heat conductivity is interposed between the dielectric substrate and the frame member, thereby radiating heat to the dielectric substrate side. The effect is enhanced, and the need to attach a heat radiator to the back surface of the semiconductor bare chip is eliminated.

According to the second aspect of the present invention, (a) the flat plate-shaped semiconductor bare chip and (b) the semiconductor bare chip so as to surround only the side surface of the flat-shaped semiconductor bare chip.
In the extended position of the semiconductor bare chip with the same thickness as
(C) good thermal conductivity between the frame-like member attached via a good thermal conductive adhesive and this frame-like member ;
Semiconductor bare chip so that the material of
And a dielectric substrate to be mounted on a chip .

That is, according to the second aspect of the present invention, only the side surface of the semiconductor bare chip is provided with an adhesive having good heat conductivity,
By letting the dielectric substrate radiate heat from the attached frame member with good heat conductivity through the material with good heat conductivity,
The need to attach a heat radiator to the back surface of the semiconductor bare chip is eliminated.

According to a third aspect of the present invention, the semiconductor bare chip and the frame-shaped member are formed with gold bumps having excellent thermal conductivity on the surfaces facing the dielectric substrate. As the bump, another conductive material such as a solder bump may be used. However, the use of gold improves the heat radiation characteristics.

According to the fourth aspect of the present invention, the semiconductor bare chip has gold bumps formed on the surface facing the dielectric substrate, and the gap between the frame member and the dielectric substrate is filled with silver paste. It is characterized by having. The frame member is
By filling a material having excellent heat conductivity instead of forming the bumps, the heat radiation effect can be similarly increased.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments.

First Embodiment

FIG. 1 shows a bare chip mounting method according to a first embodiment of the present invention. A frame member 103 having good heat conductivity is attached around a semiconductor bare chip 101 of the first embodiment via an adhesive 102 having good heat conductivity. Here, the adhesive 102 is an epoxy resin, and the frame member 103 is an aluminum material. The adhesive 102 is more preferably added with metal particles or the like as a filler. In this embodiment, the semiconductor bare chip 10
1 is a size of 6 mm square, and the frame-shaped member 103 has an inner size of 6.5 mm square and an outer size of 9 mm square.

The first bumps 10 made of gold having a height of 50 μm are formed on the electrodes on the circuit surface of the semiconductor bare chip 101.
4 ₁ are formed, a second bump 104 ₂ similarly height consists 50μm gold on top of the frame member 103 is formed. The first bump 104 ₁ is connected to a land of a dielectric substrate 105 made of alumina. Second
The bumps 104 ₂ are connected to a conductive pattern arranged for connection of the frame-shaped member 103 of the dielectric substrate 105. In addition, the semiconductor bare chip 101, the frame-shaped member 10
3 and the dielectric substrate 105 so as to be sealed.
An epoxy-based electrically insulating resin 106 is filled. For the dielectric substrate 105, other commonly used materials for circuit boards can be used. For example, resin-based materials such as glass epoxy, polyimide, and Teflon, and materials generally used for electronic circuit boards, such as glass ceramic, can be used.

In the semiconductor integrated circuit device manufactured by such a mounting method, when power is supplied to the semiconductor bare chip 101, the heat generated on the circuit surface thereof generates the first bump 104 _1.
The heat is dissipated to the dielectric substrate 105 via the side surface, and is transmitted to the frame member 103 via the adhesive 102 on the side surface. And
The heat is further radiated from the frame-shaped member 103 to the dielectric substrate 105 through the outside and the second bumps 104 ₂ , and the heat radiating characteristics can be improved by these mutual heat radiating paths.

In this manner, the frame-shaped member 103 is attached to the semiconductor bare chip 101, and the frame-shaped member 103 is
By being connected to the dielectric substrate 105 via a bump 104 _2, heat radiation of the semiconductor bare chip 101 is improved, the semiconductor integrated circuit can be stably operated. Moreover, as shown in FIG.
Since there is no need to attach a heat radiator to the back of 01,
The whole module can be made low profile. In this embodiment, the first and second bumps 104 ₁ , 104 ₂
Are exactly the same size, but the second bump 10
4 ₂ may be used as the wider bump contact area between the semiconductor bare chip 101 and the dielectric substrate 105 that is natural.

Second Embodiment

FIG. 2 shows a bare chip mounting method according to a second embodiment of the present invention. In FIG. 2, the same portions as those in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. In the second embodiment, the gap between the lower surface of the frame-like member 103 attached to the side surface of the semiconductor bare chip 101 via the adhesive 102 and the corresponding portion of the dielectric substrate 105 is made of a good heat conductive epoxy-based material. Adhesive 121
Is filled. The adhesive 121 does not necessarily have to have good insulating properties. Therefore, instead of the epoxy adhesive 121, for example, a conductive adhesive such as a silver paste can be used.

Although gold was used for the first and second pumps in the first embodiment and the first bump in the second embodiment described above, depending on the state of heat radiation, other metals or alloys may be used. It is also possible to use bumps, for example solder bumps. As for the frame member, aluminum was used in the first and second embodiments. Instead, a metal having good heat conductivity such as copper or copper tungsten or a ceramic material having good heat conductivity such as aluminum nitride was used. It is also possible. Although the frame-shaped member is manufactured according to the semiconductor bare chip, the interval between the inner and outer dimensions is not constant, and the outer dimension should be as large as possible.

[0024]

As described above, claims 1 and 2
According to the invention described in Item 2 , the semiconductor bare chip is the same as the semiconductor bare chip so as to surround only the side surface of the semiconductor bare chip.
Good heat transfer to the extended position of the semiconductor bare chip
We decided to attach a conductive frame. in this way,
On the semiconductor bare chip surface opposite to the dielectric substrate,
Since no members are attached, the entire module is low profile.
And a higher density of the semiconductor integrated circuit device can be achieved. Also, the side of the semiconductor bare chip and good heat
Conductive frame members are attached with a good thermal conductive adhesive
Not only between the frame-shaped member and the dielectric substrate
Good heat dissipation due to high thermal conductivity material
There is an effect that characteristics can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a bare chip mounting state according to a first embodiment of the present invention.

FIG. 2 is a sectional view illustrating a bare chip mounting state according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a conventional bare chip mounting state.

FIG. 4 is a cross-sectional view showing a conventionally proposed bare chip mounting state.

[Explanation of symbols]

Reference Signs List 101 semiconductor bare chip 102 adhesive 103 frame-shaped member 104 ₁ first bump 104 ₂ second bump 105 dielectric substrate 106 electrically insulating resin 121 epoxy-based adhesive

Claims (4)

(57) [Claims] 1. A semiconductor chip having a thickness equal to that of a semiconductor bare chip so as to surround only a side surface of the semiconductor bare chip.
Good thermal conductivity bonding to the extended position of the conductor bare chip
A first step of mounting a frame member having good thermal conductivity via an agent, and flip-chip mounting a semiconductor bare chip on a dielectric substrate such that a material having good thermal conductivity is interposed between the frame member and the frame member. A bare chip mounting method, comprising: a second step. 2. A plate-shaped semiconductor bare chip and a semiconductor Beachi in the flat plate-like semiconductor side only the same thickness as the semiconductor bare chip so as to surround of a bare chip
To the extended position of the
A good heat conductive material is interposed between the attached good heat conductive frame member and the frame member.
And a dielectric substrate on which the semiconductor bare chip is flip-chip mounted . 3. The semiconductor integrated circuit device according to claim 2, wherein a gold bump is formed on each of the semiconductor bare chip and the frame-shaped member on a surface facing the dielectric substrate. 4. The semiconductor bare chip has a gold bump formed on a surface facing the dielectric substrate, and a gap between the frame-shaped member and the dielectric substrate is filled with a silver paste. 3. The semiconductor integrated circuit device according to claim 2, wherein