JP6801507B2 - Electronic devices and their manufacturing methods, heat conductive parts - Google Patents

Description

The present invention relates to an electronic device, a method for manufacturing the same, and a heat conductive component.

The degree of integration of semiconductor elements has been continuously improved with the progress of microfabrication technology, but the conventional method of increasing the density two-dimensionally is physically reaching its limit.
Various methods have been studied as a method of overcoming the limitation and further increasing the degree of integration, but in recent years, the 3D-LSI technology for increasing the degree of integration by three-dimensionally stacking LSI chips has attracted attention. ing.

According to this technology, by three-dimensionally stacking LSI chips, it is possible to dramatically improve the degree of integration of semiconductor elements as compared with the case where LSI chips are arranged two-dimensionally on a circuit board. it can.
However, in a three-dimensional laminated structure such as a 3D-LSI structure, there is a problem of how to dissipate the heat generated by each LSI chip (semiconductor chip).

Further, since the underfill material is filled between the laminated chips, efforts are continuously made to improve the thermal conductivity of the underfill material.

JP-A-2008-177232 Japanese Unexamined Patent Publication No. 7-21257 JP-A-2005-2005333 JP-A-2007-262295 JP-A-2002-053736 JP-A-2007-146129

However, since the underfill material is a resin composition, there is a limit even if, for example, an inorganic filler having high thermal conductivity is dispersed to increase the thermal conductivity, and even if the thermal conductivity is increased to the limit. Even if the underfill material is filled between the laminated chips, it is difficult to obtain a sufficient heat dissipation effect.
An object of the present invention is to efficiently conduct heat generated by individual chips between stacked chips so that a sufficient heat dissipation effect can be obtained.

In one aspect, the electronic device is a heat conductive component provided in a space between a semiconductor device having a three-dimensional laminated structure in which a plurality of semiconductor chips are three-dimensionally laminated via a connection portion and the plurality of semiconductor chips. The heat conductive component is made of a shape memory alloy, and a shape having a plurality of wavy irregularities is memorized, and a plurality of vertical members provided in parallel are connected to each other at the highest point and the lowest point of the unevenness. It is provided along the vertical members so as to be alternately located on the upper side and the lower side of the plurality of horizontal members and the structure including the plurality of horizontal members provided in the above manner, and has a higher thermal conductivity than the shape memory alloy. It is provided with fibers made of high material, and the vertical member has a shape having a plurality of wavy irregularities, and the highest point and the lowest point of the plurality of irregularities on each of the surfaces of the semiconductor chips located above and below the heat conductive component. A plurality of cross members connected to the above are pressed against each other and the fibers are in contact with each other.

In one embodiment, the heat conductive component is made of a shape memory alloy, and a shape having a plurality of wavy irregularities is stored, and a plurality of vertical members provided in parallel are connected to each other at the highest point and the lowest point of the unevenness. It is provided along the vertical members so as to be provided with a plurality of horizontal members provided so as to be arranged so as to be alternately located on the upper side and the lower side of the plurality of horizontal members and the structure deformed to be flat. , A fiber made of a material having a higher thermal conductivity than a shape memory alloy.

In one aspect, a method of manufacturing an electronic device is a shape memory alloy in a space between a plurality of semiconductor chips of a semiconductor device having a three-dimensional laminated structure in which a plurality of semiconductor chips are three-dimensionally laminated via a connection portion. A shape having a plurality of wavy irregularities is stored, and a plurality of vertical members provided in parallel and a plurality of horizontal members provided so as to connect the highest points and the lowest points of the irregularities are provided. From a structure that has been deformed to be flat and a material that is provided along the vertical members so as to be alternately located on the upper and lower sides of a plurality of horizontal members and has a higher thermal conductivity than a shape memory alloy. A process of inserting a heat conductive component provided with a fiber, and a plurality of cross members connected to the highest and lowest points of a plurality of irregularities are pressed against each of the surfaces of semiconductor chips located above and below the heat conductive component. It includes a step of heating the heat conductive component to a shape recovery temperature that restores the heat conductive component to a shape having a plurality of wavy irregularities so that the fibers come into contact with each other.

As one aspect, there is an effect that the heat generated by the individual chips can be efficiently conducted between the stacked chips so that a sufficient heat dissipation effect can be obtained.

(A) to (C) are schematic views showing the configuration of the electronic device and the heat conductive component according to the present embodiment, (A) is a perspective view, and (B) and (C) are plan views. is there. (A) to (C) are schematic cross-sectional views for explaining the shape change of the shape memory alloy used for the heat conductive component according to this embodiment. (A) and (B) are schematic views for explaining the composition and manufacturing method of the structure (skeleton) constituting the heat conductive component according to the present embodiment, and (A) is a sectional view. (B) is a plan view. (A) and (B) are schematic views for explaining the configuration of the heat conductive component according to the present embodiment [state in which fibers are woven into the structure (skeleton)] and the manufacturing method thereof, and (A). ) Is a cross-sectional view, and (B) is a plan view. (A) to (C) are schematic cross-sectional views for explaining the manufacturing method (method of forming a heat dissipation path using heat conductive parts) of the electronic device according to the present embodiment.

Hereinafter, the electronic device according to the embodiment of the present invention, the manufacturing method thereof, and the heat conductive component will be described with reference to FIGS. 1 to 5.
As shown in FIGS. 1A to 1C, the electronic device according to the present embodiment is a semiconductor having a three-dimensional laminated structure in which a plurality of semiconductor chips 1 are three-dimensionally laminated via a connecting portion 2. It includes a device 3 and a heat conductive component 4 provided in a space between a plurality of semiconductor chips 1.

Note that FIG. 1 (A) omits the illustration of the heat conductive component 4. Further, in FIGS. 1 (B) and 1 (C), the underfill material 9 is not shown.
Here, the semiconductor device 3 having a three-dimensional laminated structure is, for example, a semiconductor device (3D-LSI; 3D-LSI structure) configured by three-dimensionally stacking LSI chips, and is provided, for example, on a circuit board. Be done.

Further, the heat conductive component 4 is along the vertical member 5 so as to be alternately located on the upper side and the lower side of the structure 7 having the plurality of vertical members 5 and the plurality of horizontal members 6 and the plurality of horizontal members 6. [See, for example, FIGS. 4 (B) and 5 (C)]. The heat conductive component 4 is also referred to as a heat transfer member.
Here, the structure 7 is made of a shape memory alloy, and the plurality of vertical members 5 are memorized in a shape having a plurality of wavy irregularities and are provided in parallel, and the horizontal members 6 are provided with the highest points of the irregularities. And the lowest points are provided to connect to each other [see, for example, FIGS. 3 (A) and 3 (B)].

Here, the entire structure 7, that is, the vertical member 5 and the horizontal member 6 is made of a shape memory alloy, but the present invention is not limited to this, and for example, only the vertical member 5 is made of a shape memory alloy. The cross member 6 may be made of another material.
Here, the shape memory alloy is, for example, a Ni—Ti alloy. Further, the structure 7 is made of a shape memory alloy, and two parallel vertical members 5 having a large number of corrugated periodic irregularities are individually crossed between the highest points and the lowest points of the irregularities. It is connected by 6.

The fiber 8 is made of a material having a higher thermal conductivity than the shape memory alloy.
Here, the fiber 8 is, for example, a metal fiber or a carbon fiber. Further, the fibers 8 are provided along the vertical member 5 so as to be alternately located on the upper side and the lower side of the plurality of horizontal members 6. That is, the fibers 8 are woven so that the positional relationships between the cross members 6 and the fibers 8 are staggered between the adjacent cross members 6 among the plurality of cross members 6.

Then, the vertical member 5 of the structure 7 has a shape having a plurality of wavy irregularities, and the highest and lowest points of the plurality of irregularities are formed on each of the surfaces of the semiconductor chips 1 located above and below the heat conductive component 4. A plurality of cross members 6 connected to the above are pressed against each other so that the fibers 8 are in contact with each other.
By providing the heat conductive component 4 configured in this way in the space between the plurality of stacked chips 1, the heat generated by the individual chips 1 inside the semiconductor device 3 forming the three-dimensional laminated structure is generated. It is possible to realize a heat dissipation structure that efficiently moves and dissipates heat.

Further, in the present embodiment, the underfill material 9 which is filled in the space between the plurality of laminated chips 1 and hardened is also provided.
In the semiconductor device 3 or the electronic device provided with the heat conductive component 4 provided in the space between the upper and lower chips 1 forming the three-dimensional laminated structure, the heat conductive component 4 has recovered its shape, that is, The vertical member 5 is in a state of being restored to a shape having a plurality of wavy irregularities [see, for example, FIG. 5 (C)].

On the other hand, the heat conductive component 4 is in a flatly deformed state before being provided in the space between the upper and lower chips 1 constituting the three-dimensional laminated structure [for example, FIGS. 3A and 3A, FIG. B), see FIG. 4 (A), FIG. 4 (B)].
That is, the heat conductive component 4 is made of a shape memory alloy, and a shape having a plurality of wavy irregularities is stored, and the plurality of vertical members 5 provided in parallel are connected to the highest points and the lowest points of the irregularities. Along the vertical member 5, the structure 7 is provided so as to be provided so as to be provided, and the structure 7 is deformed so as to be flat, and the structure 7 is alternately located on the upper side and the lower side of the plurality of horizontal members 6. It is provided with a fiber 8 made of a material having a higher thermal conductivity than a shape memory alloy.

Further, in the present embodiment, the fiber 8 includes a first fiber 8A and a second fiber 8B provided so as to be located on the opposite side of the cross member 6 in the vertical direction with respect to the first fiber 8A. [See, for example, FIGS. 4 (A) and 4 (B)].
Therefore, in a state where the vertical member 5 has a plurality of wavy irregularities, one of the first fiber 8A and the second fiber 8B is the surface of the semiconductor chip 1 located above and below the heat conductive component 4. The other of the first fiber 8A and the second fiber 8B is in contact with each of the semiconductor chips 1 without contacting each of the surfaces of the semiconductor chips 1 located above and below the heat conductive component 4. [See, for example, FIG. 5 (C)].

However, the present invention is not limited to this, and all the fibers 8 may be provided so as to be located on the same side in the vertical direction with the cross member 6 interposed therebetween. In this case, all the fibers 8 are in contact with the surfaces of the semiconductor chips 1 located above and below the heat conductive component 4 in a state where the vertical member 5 has a plurality of wavy irregularities. It becomes a state.
By the way, in the present embodiment, as described above, underfilling between chips is performed so that the heat generated by each chip 1 inside the 3D-LSI structure can be efficiently transferred and a sufficient heat dissipation effect can be obtained. A heat conductive component 4 configured as described above is provided so as to be embedded in the material 9 [see, for example, FIG. 5 (C)].

In particular, in the present embodiment, as shown in FIG. 2A, for example, a corrugated plate-shaped shape memory alloy having a large number of irregularities is used. That is, a shape memory alloy is used, and a corrugated plate-like shape having a large number of irregularities is stored in the alloy.
Then, as shown in FIG. 2 (B), the entire shape is deformed flat by applying stress to the shape memory alloy that stores the corrugated plate shape.

The shape memory alloy thus deformed and flattened maintains a flat shape even when the applied stress is removed.
On the other hand, when the shape memory alloy is heated and the temperature is raised to the shape recovery temperature or higher, the shape memory alloy is deformed and restored to the original corrugated plate shape having many irregularities as shown in FIG. 2 (C). (Recover.

Utilizing the function of the deformed shape memory alloy to return to its original shape by heating in this way, thermal conductivity is provided between two vertically adjacent chips of the plurality of semiconductor chips 1 constituting the 3D-LSI structure. Form a heat dissipation path made of high material.
That is, the heat conductive component 4 in which the fiber 8 made of a material having higher thermal conductivity than the shape memory alloy is woven into the structure (skeleton) 7 made of the shape memory alloy having the above-mentioned deformation behavior is used. Then, a heat dissipation path made of a material having high thermal conductivity is formed between two adjacent chips on the upper and lower sides of the plurality of semiconductor chips 1 constituting the 3D-LSI structure.

In this case, first, the heat conductive component 4 in a flatly deformed state is inserted into the space between two vertically adjacent chips among the plurality of semiconductor chips 1 constituting the 3D-LSI structure [for example, FIG. 4]. (A), FIG. 4 (B), FIG. 1 (B), FIG. 1 (C)].
Then, the same space is filled with a thermosetting underfill material (uncured) 9 and heated for the purpose of curing the underfill material 9 [see, for example, FIG. 5 (C)]. Here, the shape recovery temperature of the shape memory alloy is set lower than the curing temperature of the underfill material 9, and the underfill material 9 is heated to the curing temperature.

As a result, the temperature of the heat conductive component 4 inserted in the space between the upper and lower chips 1 rises, and when the temperature becomes equal to or higher than the shape recovery temperature, the skeleton 7 made of a shape memory alloy stores it. It returns to its original shape (here, a corrugated plate shape with many irregularities) [see, for example, FIG. 5 (C)].
In this way, when the skeleton 7 made of the shape memory alloy is restored to the original corrugated shape with a large number of irregularities in the space between the upper and lower chips 1, the convex portions of the numerous irregularities are formed. It will be pressed against the surface of each of the upper and lower chips 1 [see, for example, FIG. 5 (C)].

As a result, the fibers 8 woven into the skeleton 7 made of the shape memory alloy are sandwiched between the convex portion of the skeleton 7 made of the shape memory alloy and the surface of the chip 1, and the surfaces of the two upper and lower chips 1 are respectively. By contacting with, a large number of heat dissipation paths are formed between the surfaces of the upper and lower chips 1.
In this way, since a large number of heat dissipation paths are formed by the fibers 8 having high thermal conductivity between the surfaces of the two upper and lower chips 1, only the underfill material 9 is filled in the space between the chips. Compared with the case, the heat transfer performance between the chips can be significantly improved, and a sufficient heat dissipation effect can be obtained.

In particular, the heat generated by each chip 1 can be efficiently dissipated in the stacking direction of the chips 1. Further, since the fiber 8 having high thermal conductivity also forms a heat dissipation path in the in-plane direction of the chip 1, the heat locally generated in the chip is efficiently transferred to the in-plane direction of the chip 1. It is possible to dissipate heat. Further, by extending the fiber 8 to the outside of the 3D-LSI structure, it is possible to efficiently transfer heat to the outside of the 3D-LSI structure and dissipate heat.

As a result, the heat locally generated inside the 3D-LSI structure can be efficiently transferred to both the stacking direction and the in-plane direction of the chip 1 to dissipate heat, and the heat can be dissipated locally inside the 3D-LSI structure. It is possible to suppress an increase in temperature and avoid the occurrence of problems caused by heat generation of the chip 1.
Further, as described above, when the heat conductive component 4 is composed of the structure 7 and the fiber 8 made of a shape memory alloy and provided inside the 3D-LSI structure as described above, the chips 1 are laminated. The fibers 8 having high thermal conductivity can be brought into contact with each of the surfaces of the two upper and lower chips without affecting the alignment, and a heat dissipation path having high thermal conductivity can be easily formed.

Next, a method of manufacturing the electronic device according to the present embodiment will be described.
The method for manufacturing an electronic device of the present embodiment is to create a space between a plurality of semiconductor chips 1 of a semiconductor device 3 having a three-dimensional laminated structure in which a plurality of semiconductor chips 1 are three-dimensionally laminated via a connection portion 2. A step of inserting the heat conductive component 4 [see, for example, FIG. 5 (B), FIG. 1 (B), FIG. 1 (C)] and a step of heating the heat conductive component 4 [see, for example, FIG. 5 (C)]. Including.

In particular, in the process of inserting the heat conductive component, a shape made of a shape memory alloy and having a plurality of wavy irregularities is memorized, and a plurality of vertical members 5 provided in parallel and the highest and lowest points of the irregularities The structure 7 is provided with a plurality of cross members 6 provided so as to connect the members, and the structure 7 is deformed to be flat, and the vertical members are alternately located on the upper and lower sides of the plurality of cross members 6. Insert the heat conductive component 4 provided along the line 5 and including the fiber 8 made of a material having a higher thermal conductivity than the shape memory alloy [for example, FIGS. 5 (B), 1 (B), 1 (C). )reference].

Further, in the step of heating the heat conductive component 4, a plurality of cross members 6 connected to the highest and lowest points of the plurality of irregularities are formed on the surfaces of the semiconductor chips 1 located above and below the heat conductive component 4. The heat conductive component 4 is heated to a shape recovery temperature that restores the shape to have a plurality of wavy irregularities so that the fibers 8 are pressed against each other [see, for example, FIG. 5 (C)].
Further, after the step of inserting the heat conductive component 4, a step of filling the space between the plurality of semiconductor chips 1 with the underfill material 9 and a step of heating the underfill material 9 to a curing temperature to cure it [for example, [See FIG. 5 (C)] may be included.

In this case, the shape recovery temperature of the shape memory alloy may be set lower than the curing temperature of the underfill material 9, and the step of heating the heat conductive component 4 may be performed in the step of curing the underfill material 9. ..
Further, the fiber 8 is provided with a first fiber 8A and a second fiber 8B provided so as to be located on the opposite side of the cross member 6 in the vertical direction with respect to the first fiber 8A, and heat conduction is provided. When the shape of the heat conductive component 4 is restored in the step of heating the component 4, one of the first fiber 8A and the second fiber 8B is located on the surface of the semiconductor chip 1 located above and below the heat conductive component 4, respectively. The other of the first fiber 8A and the second fiber 8B is located between the semiconductor chips 1 without contacting each of the surfaces of the semiconductor chips 1 located above and below the heat conductive component 4. [For example, see FIG. 5 (C)].

Hereinafter, the heat conductive component, the electronic device, and the manufacturing method thereof configured as described above will be described in more detail with reference to specific examples.
In this specific example, as shown in FIGS. 3 (A) and 3 (B), for example, the structure (skeleton) 7 made of a shape memory alloy, which is a component of the heat conductive component 4, has two parallel vertical structures (skeletons) 7. It has a ladder-like structure in which the members 5 are connected by a large number of horizontal members 6 in directions orthogonal to the vertical members 5.

Here, a large number of cross members 6 are arranged parallel to each other and at equal intervals. It should be noted that the present invention is not limited to this, and it may be provided so as to connect the highest points and the lowest points of the unevenness of the vertical member 5 to each other.
A Ni—Ti alloy is used as the material for the shape memory alloy constituting the skeleton 7. By adjusting the composition and processing conditions of Ni-Ti alloys, the shape recovery temperature can be set within the temperature range of about 100 ° C from room temperature, which is useful for constructing the heat dissipation path formation process described later. Suitable.

Then, the skeleton 7 made of the shape memory alloy is subjected to a process of storing the shapes as shown in FIGS. 3 (A) and 3 (B), for example.
Specifically, the skeleton 7 having a ladder-like structure is processed so that the two vertical members 5 periodically have a corrugated plate-like shape having a large number of irregularities.
At this time, the positional relationship between the unevenness of the two vertical members 5 and the horizontal member 6 is set so that the horizontal member 6 always connects the vertices (highest point and lowest point) of the convex portion of the unevenness of the vertical member 5. adjust. That is, the horizontal member 6 is arranged so that the highest position (highest point) of the upward convex portion of the vertical member 5 and the lowest position (lowest point) of the downward convex portion are connected to each other.

Here, in the process for memorizing the shape, the skeleton 7 is restrained by pressing with a mold or the like so as to maintain the shape as shown in FIGS. 3 (A) and 3 (B), and then about 400 to about 400 to about. It is carried out by holding it in a state of being heated to 500 ° C. for about 10 minutes to about 30 minutes and then cooling it to room temperature.
Here, in the process of forming the skeleton 7 into a corrugated plate shape, if the amount of deformation of the vertical member 5 is steep, the shape recovery effect may not be exhibited well. Therefore, the curvature of the unevenness of the vertical member 5 is changed. When determining, for example, it is desirable that the amount of deformation strain does not exceed about 7 to about 8%.

It should be noted that the shape memory processing is actually performed only on the vertical member 5 so as to have corrugated unevenness, and the cross member 6 is not required to have the characteristics as a shape memory alloy. The cross member 6 does not necessarily have to be made of a shape memory alloy. However, joining a vertical member 5 made of a shape memory alloy and a horizontal member 6 made of a different material to form a ladder-like structure as shown in FIGS. 3 (A) and 3 (B) is rather possible. Since a complicated process is required, it is actually convenient to mold the vertical member 5 and the horizontal member 6 from the same shape memory alloy base material.

As described above, when the skeleton 7 of the heat conductive component 4 is subjected to the process of memorizing the shapes as shown in FIGS. 3 (A) and 3 (B), stress is applied to the entire skeleton. It is deformed so that the corrugated unevenness is spread flat.
Here, since the shape memory alloy can be easily deformed at room temperature, for example, if the entire skeleton having the shape shown in FIG. 3 is crushed with a flat plate, the corrugated plate shape given to the vertical member is formed. The unevenness of the skeleton is lost, and the entire skeleton can be formed into a flat ladder-like shape.

In this way, after memorizing the shape having the corrugated plate-like unevenness, as shown in FIGS. 4 (A) and 4 (B), the thermal conductivity with respect to the flatly deformed skeleton 7. High fiber 8 (fibrous member) is woven in a direction parallel to the vertical member 5.
In this way, the fibers 8 are woven into the flatly deformed skeleton 7 by knitting the fibers 8 in a shape having corrugated unevenness, and then applying stress by, for example, pressing. In addition, if the fiber 8 is deformed flat, the fiber 8 may be cut at that time.

In addition, in FIG. 4A and FIG. 4B, the case where four fibers 8 are woven into the skeleton 7 is shown as an example.
In this specific example, the fibers 8 having high thermal conductivity are woven by passing them through the upper side and the lower side of the adjacent cross members 6 alternately. After passing the upper side of a certain cross member 6, the cross member 6 next to the cross member 6 passes the lower side, and then the cross member 6 next to the cross member 6 passes the upper side of the cross member 6 again.

Further, the fiber 6 is divided into two groups, that is, a fiber (first fiber) 8A and a fiber (second fiber) 8B.
Then, when the fibers 8 are woven into the cross member 6 of the skeleton 7, the upper and lower passing sides of the same cross member 6 are reversed between the two groups of the fibers 8A and 8B.
For example, if a group of fibers 8A is woven so as to start from a certain cross member 6 and pass through the cross member 6 as above, below, above, below, and so on, the other group of fibers 8B is , The bottom, top, bottom, top, etc. of the cross member 6 at the same position are woven so as to pass through.

By doing so, the fibers 8 having high thermal conductivity pass through both the upper side and the lower side of any of the cross members 6.
As a result, in a state where the skeleton 7 is deformed flat, which is the horizontal member 6 provided on the upward convex portion (highest point) of the vertical member 5, and which is the downward convex portion (lowest point) of the vertical member 5. Even if it is not known which of the cross members 6 is provided in, one of the groups of fibers 8A or 8B is sandwiched between the cross members 6 and the surface of the chip 1 and is placed on the surface of the chip 1. Can be contacted. Therefore, the fiber 8 can be easily woven.

In addition, in a state where the skeleton 7 is deformed flat, which is the horizontal member 6 provided in the upward convex portion (highest point) of the vertical member 5, and which is the downward convex portion (lowest point) of the vertical member 5. When it is known which of the provided cross members 6 is, all the fibers 8 are woven so as to alternately pass through the upper side and the lower side of the adjacent cross members 6 without dividing into groups. Just do it.
Here, in order to show that the cross member 6 is passed upside down, the fibers 8 having high thermal conductivity are divided into two groups, the fibers 8A and the fibers 8B, and are shown with different codes. There is no difference between the fibers 8A and the fibers 8B except for the upper or lower side of the cross member 6, and both are the same fibers made of exactly the same material.

Further, here, the number of fibers 8 woven into the skeleton 7 is four, but the number of fibers 8 woven into the skeleton 7 is not limited to this, and in particular, depending on the length of the cross member 6 of the skeleton 7 and the like. You can increase or decrease as much as you can.
Next, a method of forming a heat dissipation path in an electronic device including a semiconductor device 3 having a three-dimensional laminated structure using the heat conductive component 4 manufactured as described above, that is, manufacturing the electronic device of this specific example. The method will be described with reference to FIGS. 5 (A) to 5 (C).

Here, the case where the heat conductive component 4 manufactured as described above is used to form a heat dissipation path between two vertically adjacent chips 1 among a plurality of chips 1 constituting the 3D-LSI structure. Let's take an example.
First, as shown in FIG. 5 (A), a plurality of chips 1 are three-dimensionally laminated via a connecting portion 2 to manufacture a semiconductor device 3 having a 3D-LSI structure [for example, FIG. 1 (A). )reference].

Here, as shown in FIG. 5A, two chips 1 adjacent to each other on the upper and lower sides, that is, connection terminals 10 (electrodes; for example, Cu pillars and bumps) provided on the upper chip and the lower chip are connected to each other. By joining with solder 11, a plurality of chips 1 are three-dimensionally laminated via the connecting portion 2 to produce a semiconductor device 3 having a 3D-LSI structure.
In the semiconductor device 3 having such a 3D-LSI structure, the upper and lower chips 1 are electrically connected by a connecting portion 2 composed of a connecting terminal 10 and a solder 11. Although not shown, the front surface side and the back surface side of the chip 1 are connected by a TSV (Through Silicon Via) formed so as to penetrate the chip 1.

Further, in the semiconductor device 3 having such a 3D-LSI structure, a plurality of chips (LSI chips) 1 are not arranged two-dimensionally on the circuit board as in the conventional case, but are arranged on the chip surface. Since the layers are three-dimensionally stacked so as to overlap in the vertical direction, the degree of integration can be dramatically improved.
It should be noted that there is nothing in the place where the connecting portion 2 between the upper and lower chips 1 does not exist.

Next, as shown in FIG. 5B, the above-mentioned space is formed between the two upper and lower chips 1, that is, the space between the plurality of connecting portions 2 connecting the upper and lower chips 1. The heat conductive component 4 produced in this manner is inserted.
At this time, the heat conductive component 4 is arranged so as not to come into contact with the connecting portion 2 so that a short circuit does not occur between the connecting portions 2 that electrically connect the chips.

For example, as shown in FIG. 1 (B), a plurality of heat conductive components 4 may be arranged side by side and arranged in parallel in a portion where the connecting portions 2 which are arranged in an array in a plane do not exist. As shown in 1 (C), a plurality of heat conductive components 4 may be arranged in a direction orthogonal to these and arranged in a mesh shape. The number of heat conductive parts 4 to be inserted may be arbitrarily determined as needed.

Next, with the heat conductive component 4 inserted as described above, for example, a thermosetting underfill material 9 is placed in the space between the upper and lower chips 1 as shown in FIG. 5 (C). Fill in an uncured liquid state.
Then, the whole is heated for the purpose of curing the underfill material 9.
By this heating, the temperature of the heat conductive component 4 also starts to rise, and eventually reaches a temperature higher than the shape recovery temperature of the shape memory alloy constituting the skeleton 7 of the heat conductive component 4.

Then, the vertical member 5 of the skeleton 7 of the heat conductive component 4 is restored to a shape having a large number of memorized corrugated periodic irregularities.
Here, a plurality of horizontal members 6 are arranged so as to be passed between the two vertical members 5 at the positions of the vertices (highest and lowest points) of the convex portions of the vertical members 5 of the skeleton 7. There is.
When the fibers 8 are divided into groups and woven as described above, either the fibers 8A or the fibers 8B always pass through the side of the plurality of cross members 6 facing the surface of the chips 1. ..

Therefore, by restoring the shape of the vertical member 5 of the skeleton 7, either the group of the fibers 8A or 8B is sandwiched between the horizontal member 6 and the respective surfaces of the upper and lower chips 1, and the upper and lower chips are sandwiched. It is pressed against each surface of 1 and comes into contact with each surface of the upper and lower chips 1.
For example, in FIG. 5 (C), at the position indicated by reference numeral X, one group of fibers 8A is pressed against the surface of the upper chip 1 by the cross member 6 of the skeleton 7, while FIG. 5 (C) shows. At the position indicated by the symbol Y, the fibers A of the same group are pressed against the surface of the lower chip 1 by the cross member 6. In this way, the fibers 8A of one group are alternately pressed against the respective surfaces of the upper and lower chips 1 by all the cross members 6.

As a result, the fibers 8A of one group are pressed against both surfaces of the upper and lower chips 1, so that heat conduction that assists the transfer of heat between the upper and lower chips through the fibers 8A of one group. A large number of excellent heat dissipation paths are formed.
Further, the fibers 8A of one group not only facilitate the transfer of heat between the upper and lower chips, but also have the effect of assisting the transfer of heat in the in-plane direction of the chips 1.

Further, when the fibers 8 are divided into groups and knitted as described above, the fibers 8B of the other group do not come into contact with the surfaces of the upper and lower chips 1 and do not contribute to heat transfer between the chips, but one of them. It remains inside the underfill material 9 together with the fibers 8A of the group, and plays a role of assisting the heat transfer in the in-plane direction of the chip inside the underfill material 9.

By extending the fibers 8A and 8B not only to the range where the chips 1 are laminated but also to the outside of the laminated structure of the 3D-LSI, heat is derived from the inside of the underfill material 9 to the outside. It is also possible to release it.
Then, when the underfill material 9 is completely cured, the positions of the heat conductive component 4, that is, the positions of the vertical member 5, the horizontal member 6, and the fiber 8 in a state where the fibers 8 are pressed against the surfaces of the upper and lower chips 1. Is fixed.

The underfill material 9 is, for example, an insulating resin composition, and plays a role of mechanically fixing the laminated chips and sealing and protecting the connecting portion 2 between the chips.
Further, in the case of producing by the process as described above, the shape of the shape memory alloy constituting the skeleton 7 of the heat conductive component 4 inside the liquid underfill material 9 before the underfill material 9 is completely cured. The shape recovery temperature of the shape memory alloy is set lower than the curing temperature of the underfill material 9 so that the recovery is performed.

For example, since the curing temperature of a general thermosetting epoxy resin is about one hundred and several tens of degrees Celsius, when using a Ni—Ti-based shape memory alloy, the shape recovery temperature is set to about 100 ° C. Then, the process as described above can be constructed.
Further, as the fiber 8 (fibrous material) having high thermal conductivity to be woven into the skeleton 7 of the thermal conductive component 4, for example, copper having a thermal conductivity of about 398 W / (m · K) and thermal conductivity of about 429 W / ( By using pure metal fibers such as m · K) silver and gold having a thermal conductivity of about 310 W / (m · K), it is possible to form an extremely effective heat dissipation path.

Further, by using these pure metal fibers, not only the heat conduction between the chips can be improved, but also the heat conductivity of silicon is about 168 W / (m · K), so that the chip surface It is considered to greatly contribute to the improvement of heat conduction in the inward direction.
Furthermore, by utilizing pitch-based carbon fibers having a thermal conductivity exceeding about 1000 W / (m · K), it is possible to form a more efficient heat dissipation path.

By the way, the reason why the heat conductive component 4 configured as described above is used to form a heat dissipation path between the upper and lower chips is as follows.
In the 3D-LSI structure, the problem is how to release the heat generated in each LSI chip and cool it.
For example, an LSI chip located at the upper end or the lower end of a laminated structure can be provided with a heat radiation path by directly contacting the heat radiation fin or the circuit board, so that the heat generated by the chip at these positions can be generated by the 3D-LSI. It is relatively easy to escape to the outside of the structure.

However, since it is difficult to provide a heat dissipation path for an LSI chip located at a position sandwiched from above and below by another LSI chip, heat generated by the LSI chip at such a position can be efficiently transferred to the outside of the 3D-LSI structure. It is difficult to escape.
When an element having a large heat generation amount such as a CPU is arranged at such a position, there is a concern that serious problems such as malfunction and failure caused by a local temperature rise of the chip may occur.

Based on this, it is conceivable to increase the thermal conductivity of the underfill material provided between the chips.
Here, the underfill material is generally provided by curing an insulating resin composition, and the resin composition includes, for example, a thermosetting epoxy resin and fillers of various materials and shapes. Is used.

Then, by setting the material, shape, blending ratio, etc. of the filler, various properties can be imparted to the cured resin composition. For example, for the purpose of increasing the thermal conductivity of the cured resin composition, a filler made of a material having high thermal conductivity is used.
However, even if the resin composition devised to increase the thermal conductivity is filled between the chips as an underfill material, it is difficult to dramatically improve the thermal conductivity between the chips.

For example, the thermal conductivity of a standard epoxy resin alone is about 0.2 to about 0.3 W / (m · K), but even if an inorganic filler with high thermal conductivity is dispersed inside it, It is best to raise the thermal conductivity to about 4 to about 5 W / (m · K).
This thermal conductivity is overwhelmingly lower than the thermal conductivity of silicon of about 168 W / (m · K) and the thermal conductivity of copper of about 398 W / (m · K), and the presence of the underfill material is laminated. It is a major obstacle to heat conduction between the chips.

Therefore, the heat conductive component 4 configured as described above is used to form a heat dissipation path between the upper and lower chips.
Therefore, the electronic device, its manufacturing method, and the heat conductive component according to the present embodiment can efficiently conduct the heat generated by the individual chips between the laminated chips so that a sufficient heat dissipation effect can be obtained. It has the effect of being able to do it.

In particular, for a 3D-LSI structure produced by stacking a plurality of LSI chips 1, a means for forming a heat dissipation path for improving heat conduction between the chips and in the chip surface is provided, and the stacked LSIs are provided. The heat generated inside the chip 1 can be efficiently conducted to prevent a local temperature rise, and a path for releasing the heat to the outside of the laminated structure of the chip 1 can also be formed.

In the above-described embodiment, the underfill material 9 is filled, the shape recovery temperature of the shape memory alloy constituting the heat conductive component 4 is set lower than the curing temperature of the underfill material 9, and the underfill material 9 is used. The shape of the heat conductive component 4 is restored when it is heated and cured, but the present invention is not limited to this.
For example, apart from the step of heating and curing the underfill material 9, a step of heating the heat conductive component 4 to a shape recovery temperature for recovering its shape may be provided.

In this case, the shape recovery temperature of the shape memory alloy constituting the heat conductive component 4 can be set regardless of the curing temperature of the underfill material 9. Further, for example, even when the underfill material 9 is not used, the heat conductive component 4 configured as described above can be used. Further, if the shape of the shape memory alloy constituting the heat conductive component 4 is restored and then the shape is maintained even if the temperature drops, the shape can be changed by curing the underfill material 9. You don't have to hold it.

Further, for example, the shape of the heat conductive component 4 may be restored by utilizing heating when soldering the upper and lower two chips 1, that is, heating for reflowing the solder. In this case, before the upper and lower two chips 1 are solder-bonded, the heat conductive component 4 configured as described above is inserted into the space between the upper and lower chips 1 so as to the solder reflow temperature. The shape recovery temperature of the shape memory alloy constituting the heat conductive component 4 may be set low so that the shape of the heat conductive component 4 can be recovered during heating for reflowing the solder. In this case, since the positions of the upper and lower chips 1 may be displaced, it is preferable to provide a mechanism for preventing the displacement.

The present invention is not limited to the configuration described in the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
Hereinafter, additional notes will be disclosed with respect to the above-described embodiment.
(Appendix 1)
A semiconductor device having a three-dimensional laminated structure in which a plurality of semiconductor chips are three-dimensionally laminated via a connection portion, and
It is provided with a heat conductive component provided in the space between the plurality of semiconductor chips.
The heat conductive component is
A shape memory alloy is used to store a shape having a plurality of wavy irregularities, and a plurality of vertical members provided in parallel and a plurality of horizontal members provided so as to connect the highest points and the lowest points of the irregularities. Structures with materials and
It is provided along the vertical member so as to be alternately located on the upper side and the lower side of the plurality of horizontal members, and includes fibers made of a material having a higher thermal conductivity than the shape memory alloy.
The vertical member has a shape having a plurality of wavy irregularities, and is connected to the highest point and the lowest point of the plurality of irregularities on each of the surfaces of the semiconductor chips located above and below the heat conductive component. An electronic device characterized in that a plurality of cross members are pressed against each other and the fibers are in contact with each other.

(Appendix 2)
The electronic device according to Appendix 1, wherein the space between the plurality of semiconductor chips is filled with a cured underfill material.
(Appendix 3)
The fiber includes a first fiber and a second fiber provided so as to be located on the opposite side of the cross member in the vertical direction with respect to the first fiber.
In a state where the vertical member has a shape having a plurality of wavy irregularities, one of the first fiber and the second fiber is placed on each of the surfaces of the semiconductor chips located above and below the heat conductive component. The first fiber and the other of the second fibers are in contact with each other and are located between the semiconductor chips without contacting each of the surfaces of the semiconductor chips located above and below the heat conductive component. The electronic device according to Appendix 1 or 2, wherein the electronic device is characterized by the above.

(Appendix 4)
The electronic device according to any one of Appendix 1 to 3, wherein the shape memory alloy is a Ni—Ti alloy.
(Appendix 5)
The electronic device according to any one of Appendix 1 to 4, wherein the fiber is a metal fiber or a carbon fiber.

(Appendix 6)
A shape memory alloy is used to store a shape having a plurality of wavy irregularities, and a plurality of vertical members provided in parallel and a plurality of lateral members provided so as to connect the highest points and the lowest points of the irregularities. A structure that has a material and is deformed to be flat,
It is characterized in that it is provided along the vertical member so as to be alternately located on the upper side and the lower side of the plurality of horizontal members, and includes fibers made of a material having a higher thermal conductivity than the shape memory alloy. Thermal conductivity parts.

(Appendix 7)
The fiber is characterized by including a first fiber and a second fiber provided so as to be located on the opposite side in the vertical direction with respect to the first fiber with the cross member interposed therebetween. The heat conductive component described.
(Appendix 8)
The heat conductive component according to Appendix 6 or 7, wherein the shape memory alloy is a Ni—Ti alloy.

(Appendix 9)
The heat conductive component according to any one of Supplementary note 6 to 8, wherein the fiber is a metal fiber or a carbon fiber.
(Appendix 10)
A shape made of a shape memory alloy and having a plurality of wavy irregularities in a space between the plurality of semiconductor chips of a semiconductor device having a three-dimensional laminated structure in which a plurality of semiconductor chips are three-dimensionally laminated via a connection portion. A structure in which a plurality of vertical members provided in parallel and a plurality of horizontal members provided so as to connect the highest points and the lowest points of the unevenness are provided and deformed to be flat. A thermal conductivity comprising an object and a fiber made of a material having a thermal conductivity higher than that of the shape memory alloy, which is provided along the vertical member so as to be alternately located on the upper side and the lower side of the plurality of horizontal members. The process of inserting parts and
The plurality of cross members connected to the highest and lowest points of the plurality of irregularities are pressed against each of the surfaces of the semiconductor chips located above and below the heat conductive component so that the fibers come into contact with each other. A method for manufacturing an electronic device, which comprises a step of heating the heat conductive component to a shape recovery temperature for recovering the heat conductive component into a shape having a plurality of wavy irregularities.

(Appendix 11)
After the step of inserting the heat conductive component, a step of filling the space between the plurality of semiconductor chips with an underfill material and a step of heating the underfill material to a curing temperature to cure the underfill material are included.
The shape recovery temperature of the shape memory alloy is set lower than the curing temperature of the underfill material, and in the step of curing the underfill material, a step of heating the heat conductive component is also performed. , The method for manufacturing an electronic device according to Appendix 10.

(Appendix 12)
The fiber includes a first fiber and a second fiber provided so as to be located on the opposite side of the cross member in the vertical direction with respect to the first fiber.
When the shape of the heat conductive component is restored in the step of heating the heat conductive component, one of the first fiber and the second fiber is the surface of the semiconductor chip located above and below the heat conductive component. The first fiber and the other of the second fibers are located between the semiconductor chips without contacting each of the surfaces of the semiconductor chips located above and below the heat conductive component. The method for manufacturing an electronic device according to Appendix 10 or 11, wherein the electronic device is manufactured.

1 Semiconductor chip (LSI chip; chip)
2 Connection part 3 Semiconductor device 4 Heat conductive part 5 Vertical material 6 Horizontal material 7 Structure (skeleton)
8 fiber 8A fiber (first fiber)
8B fiber (second fiber)
9 Underfill material 10 Connection terminal 11 Solder

Claims (8)

A semiconductor device having a three-dimensional laminated structure in which a plurality of semiconductor chips are three-dimensionally laminated via a connection portion, and
It is provided with a heat conductive component provided in the space between the plurality of semiconductor chips.
The heat conductive component is
A shape memory alloy is used to store a shape having a plurality of wavy irregularities, and a plurality of vertical members provided in parallel and a plurality of horizontal members provided so as to connect the highest points and the lowest points of the irregularities. Structures with materials and
It is provided along the vertical member so as to be alternately located on the upper side and the lower side of the plurality of horizontal members, and includes fibers made of a material having a higher thermal conductivity than the shape memory alloy.
The vertical member has a shape having a plurality of wavy irregularities, and is connected to the highest point and the lowest point of the plurality of irregularities on each of the surfaces of the semiconductor chips located above and below the heat conductive component. An electronic device characterized in that a plurality of cross members are pressed against each other and the fibers are in contact with each other. The electronic device according to claim 1, wherein the space between the plurality of semiconductor chips is filled with a cured underfill material. The fiber includes a first fiber and a second fiber provided so as to be located on the opposite side of the cross member in the vertical direction with respect to the first fiber.
In a state where the vertical member has a shape having a plurality of wavy irregularities, one of the first fiber and the second fiber is placed on each of the surfaces of the semiconductor chips located above and below the heat conductive component. The first fiber and the other of the second fibers are in contact with each other and are located between the semiconductor chips without contacting each of the surfaces of the semiconductor chips located above and below the heat conductive component. The electronic device according to claim 1 or 2, wherein the electronic device is characterized by the above. The electronic device according to any one of claims 1 to 3, wherein the shape memory alloy is a Ni—Ti alloy. The electronic device according to any one of claims 1 to 4, wherein the fiber is a metal fiber or a carbon fiber. A shape memory alloy is used to store a shape having a plurality of wavy irregularities, and a plurality of vertical members provided in parallel and a plurality of lateral members provided so as to connect the highest points and the lowest points of the irregularities. A structure that has a material and is deformed to be flat,
It is characterized in that it is provided along the vertical member so as to be alternately located on the upper side and the lower side of the plurality of horizontal members, and includes fibers made of a material having a higher thermal conductivity than the shape memory alloy. Thermal conductivity parts. A shape made of a shape memory alloy and having a plurality of wavy irregularities in a space between the plurality of semiconductor chips of a semiconductor device having a three-dimensional laminated structure in which a plurality of semiconductor chips are three-dimensionally laminated via a connection portion. A structure in which a plurality of vertical members provided in parallel and a plurality of horizontal members provided so as to connect the highest points and the lowest points of the unevenness are provided and deformed to be flat. A thermal conductivity comprising an object and a fiber made of a material having a thermal conductivity higher than that of the shape memory alloy, which is provided along the vertical member so as to be alternately located on the upper side and the lower side of the plurality of horizontal members. The process of inserting parts and
The plurality of cross members connected to the highest and lowest points of the plurality of irregularities are pressed against each of the surfaces of the semiconductor chips located above and below the heat conductive component so that the fibers come into contact with each other. A method for manufacturing an electronic device, which comprises a step of heating the heat conductive component to a shape recovery temperature for recovering the heat conductive component into a shape having a plurality of wavy irregularities. After the step of inserting the heat conductive component, a step of filling the space between the plurality of semiconductor chips with an underfill material and a step of heating the underfill material to a curing temperature to cure the underfill material are included.
The shape recovery temperature of the shape memory alloy is set lower than the curing temperature of the underfill material, and in the step of curing the underfill material, a step of heating the heat conductive component is also performed. The method for manufacturing an electronic device according to claim 7.