JPH0533829B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improvement of a semiconductor device using so-called three-dimensional mounting multi-chip package technology, in which a large number of semiconductor chips are mounted in one package.

[Conventional technology]

Conventionally, in this type of semiconductor device, multiple semiconductor chips (LSI chips) are planarly mounted on multiple wiring boards, and these wiring boards are sequentially arranged side by side in the stacking direction and mounted on another wiring board. It is known to have a configuration in which these components are provided in a single package. To briefly explain such a conventional three-dimensional multi-chip package using Fig. 2 a, b, and c, numeral 1 in the figure has an active element consisting of a PN junction and its connection wiring, and has active and passive functions. Each of these semiconductor chips 1 has a certain function, such as a large-capacity memory, a large-scale logic circuit of a microprocessor, etc. All the chips 1 constitute the functions of the entire semiconductor device. 2 is a plurality of first wiring boards on which a plurality of these semiconductor chips 1 are arranged and fixed, and their functions are interconnected; 3, these first wiring boards are arranged side by side in an upright state; The first and second wiring boards 2 and 3 are the second wiring boards that interconnect the functions of the multiple semiconductor chips 1.
It is packaged by being placed on an insulating substrate 4 along with the above. Here, in the figure, 5a is an electrode (hereinafter referred to as a bump) made of a Pb-Sn alloy formed on each semiconductor chip 1 for electrically and mechanically connecting it to the first wiring board 2 side, and 5b is an electrode (hereinafter referred to as a bump) on each semiconductor chip 1. An electrode (bump) made of Pb/Sn alloy that electrically and mechanically connects the first wiring board 2 to the second wiring board side.
Further, 6 is a wire that electrically connects the second wiring board 3 and the insulating substrate 4, and 7 is an external connection electrode (external pin) for taking out the function of this semiconductor device to the outside.

In a semiconductor device with such a configuration, the PN junctions formed on the main surface of the semiconductor chip 1 are connected to each other by wiring (not shown) made of Al or the like, and the electrical functions of the PN junctions are performed on the same plane as the main surface. The structure is such that it can be taken out from any location. Therefore, if the main surface of the semiconductor chip 1 is placed parallel to and facing the main surface (substrate surface) of the first wiring board 2, the semiconductor chip 1 can be bonded by reflow bonding the bumps 5a placed in the gap. electrically connecting the functions of the chip 1 and the wiring of the first wiring board 2;
At the same time, this semiconductor chip 1 can be fixed onto the first wiring board 2. Wiring for interconnecting the semiconductor chips 1 and interconnection wiring (not shown) are formed in advance on the main surface of the first wiring board 2, so that each semiconductor chip mounted as described above The functions of 1 are connected and combined with each other. As a result, this first wiring board 2 has a plurality of semiconductor chips 1 mounted in this way.
This means that the number of functions (subsystems) is as many as the number of functions (subsystems).

On the other hand, in the first wiring board 2 on which a plurality of such semiconductor chips 1 are mounted, the electrodes 5b arranged on one side of the outer periphery in contact with the main surface (substrate surface) of the second wiring board 3 are subjected to reflow bonding. So, the second
It is disposed vertically on the main surface of the wiring board 3, thereby electrically connecting the first wiring board 2 to the second wiring board 3, and at the same time mechanically fixing it. There is. Then, on the main surface of this second wiring board 3, wiring for interconnecting the first wiring boards 2 and interconnection wiring (not shown) are formed in advance, so that the first wiring mounted on this Board 2
The individual functions (subsystems) above are connected to each other,
It will be combined. Therefore, on this second wiring board 3, all the subsystems of the first wiring board 2, that is, all the individual functions of the large number of semiconductor chips 1 housed in this semiconductor device are mounted and combined. This can be configured as follows.

Further, after mechanically fixing this second wiring board 3 to the insulating board 4 with an adhesive (not shown), the second wiring board 3 is
This is achieved by electrically connecting the function extracting electrode (not shown) formed on the wiring board 3 and the wiring (not shown) formed on the insulating board 4 with a wire 6 made of Au or the like. All functions of the second wiring board 3 are continued to the insulating board 4 side. Since the wiring on this insulating substrate 4 is connected to an external connection electrode (external pin) 7 that extracts the function of this semiconductor device to the outside, the semiconductor chip 1, the bumps 5a, the first wiring board 2, All functions of the semiconductor device are completed through the electrode 5b, the second wiring board 3, the wire 6, and the external pin 7, and can be transmitted to the outside.

Incidentally, on the insulating substrate 4 are a semiconductor chip 1, a first wiring board 2, a second wiring board 3, and a wire 6.
A lid body (not shown) that physically and chemically protects the
Since the device was mounted with a cap on it, this function was not damaged during normal handling, and the device could be operated as a multi-chip packaged semiconductor device.

[Problem that the invention seeks to solve]

By the way, according to the conventional device described above, the main surface of the semiconductor chip 1 is arranged parallel to the substrate surface of the first wiring board 2, and in such a structure, the first wiring on which the semiconductor chip 1 is mounted The thickness of the substrate 2 per substrate is the sum of the thickness of the first wiring board 2 and the thickness of the semiconductor chip 1 and the bumps 5a.
Since the first wiring board 2 is generally processed using a material having the same shape as the semiconductor chip 1,
If the thickness of the bumps 5a is ignored, half of the thickness will be the first wiring board 2, and the remaining half will be the semiconductor chip. In other words, the proportion of semiconductor chips 1 included in this first wiring board 2 is 50%. The proportion of semiconductor chips 1 included in this first wiring board 2 determines the semiconductor chip 1 packaging density (number of semiconductor chips included in the semiconductor device/semiconductor device volume) in this semiconductor device. Therefore, in order to improve this density, the first wiring board 2
The thickness of the semiconductor chip 1 must be made thinner than the thickness of the semiconductor chip 1. However, if the thickness of the first wiring board 2 is reduced, the mechanical strength for supporting the semiconductor chip 1 will be reduced, which will reduce the yield of non-defective products in the device manufacturing process. The drawback was that it was extremely difficult to increase the proportion of chip 1 to 50% or more.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to obtain a semiconductor device in which it is possible to increase the proportion of semiconductor chips included in a first wiring board without reducing the yield of non-defective products in the manufacturing process. It is an object.

[Means for solving problems]

A semiconductor device according to the present invention includes a plurality of first wiring boards each having a plurality of semiconductor chips mounted on the board surface, and a board surface on which these wiring boards are arranged in an upright state in parallel in a stacking direction. A second wiring board disposed perpendicular to the wiring board, and an insulating board on which the second wiring board is mounted and fixed and has external connection electrodes,
A plurality of semiconductor chips are mounted side by side in the stacking direction so that their main surfaces intersect with the substrate surface of the first wiring board.

[Effect]

According to the present invention, the first
The thickness of the wiring board per board is the sum of the thickness of the first wiring board, one side of the main surface of the semiconductor chip, and the thickness of the bumps, and most of the thickness is occupied by the semiconductor chip. The chip ratio can be increased, and the packaging density of the entire device can be improved.

〔Example〕

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

Figures 1a, b, c, and d show one embodiment of a semiconductor device according to the present invention, and in these figures, the same or corresponding parts as those in Figure 2 a, b, and c described above are the same. They are numbered and their explanations are omitted.

Now, according to the present invention, a plurality of semiconductor chips 1, a plurality of first wiring boards 2 each having a plurality of semiconductor chips 1 mounted on a board surface, and a plurality of first wiring boards 2 are arranged in a vertical position. A second wiring board 3 having board surfaces arranged in parallel in the stacking direction in the installed state and disposed perpendicular to the first wiring board 2; and an external connection electrode 7 on which the second wiring board 3 is mounted and fixed. A plurality of semiconductor chips are mounted side by side in the stacking direction so that their main surfaces intersect with the substrate surface of the first wiring board. It has the following characteristics.

That is, this embodiment shows the case where the above-described semiconductor chip 1 is mounted on the first wiring board 2 with its main surface perpendicular to the substrate surface. The semiconductor chip 1 mounted in this way
Needless to say, these are not only electrically connected by the bumps 5a provided at the joint portions but also mechanically fixed and held.

According to such a configuration, the thickness per board of the first wiring board 2 on which the semiconductor chip 1 is mounted is the thickness of the first wiring board 2 and one side of the main surface dimension of the semiconductor chip 1 (for example, a 10 mm square semiconductor If it is a chip, it is 10mm) and the thickness of the bump 5a (for example, 0.1mm)
is the sum of Since the thickness of the first wiring board 2 is generally the same as the thickness of the semiconductor chip 1 and thin (for example, 0.5 mm each), most of the thickness of the first wiring board 2 is equal to the main surface dimension of the semiconductor chip 1. One side will be occupied (10/11.1=0.90). This indicates that the semiconductor chip 1 occupies most of the thickness of the first wiring board 2 per board.
Therefore, if such a configuration is adopted, the first
The proportion of semiconductor chips 1 included in the wiring board 2 can be increased, and the packaging density thereof can be increased. Further, since the thickness of the first wiring board 2 is not reduced, the mechanical strength of the first wiring board 2 is not reduced, and the problem of lowering the yield of good products in the device manufacturing process is solved.

Here, such an effect is similarly exerted even when the semiconductor chips 1 described above are mounted orthogonally to the first wiring board 2, and in short, when the semiconductor chips 1 are mounted parallel to each other in the stacking direction. It is preferable to install the semiconductor chip 1 in such a state that its main surface has an angle intersecting the substrate surface of the first wiring board 2.

Note that the present invention is not limited to the structure of the embodiment described above, and the shape, structure, etc. of each part may be modified and changed as appropriate. For example, in the above-mentioned embodiment, a case was explained in which one second wiring board 3 was mounted on the insulating substrate 4, but a plurality of second wiring boards 3 may be mounted on the insulating board 4. Of course.

Furthermore, in the embodiment described above, the semiconductor chip 1
has been described as a logic circuit LSI chip, but it is easy to understand that it may have other functions such as memory and sensor, and it is not limited to LSI, but may also be MSI or SSI. Furthermore, the semiconductor chip 1 may have no active elements and only passive elements such as wiring, resistance, and capacitance are formed, and in addition to the semiconductor chip 1, the first wiring board 2, and the second wiring board 3, there may be coils, Passive elements such as capacitors may be mounted.

〔Effect of the invention〕

As explained above, according to the semiconductor device according to the present invention, a plurality of semiconductor chips, a plurality of first wiring boards formed by mounting these chips on the substrate surface,
With these first wiring boards in an upright state, a second wiring board having board surfaces arranged in parallel in the stacking direction and arranged orthogonally to the first wiring boards, and a second wiring board mounted and fixed on the outside. An insulating substrate having connection electrodes is provided, and a plurality of semiconductor chips are mounted side by side in the stacking direction so that their main surfaces intersect with the substrate surface of the first wiring board. Therefore, despite the simple and inexpensive configuration, the first
One side of the main surface of the semiconductor chip occupies most of the thickness per board of the wiring board, which makes it possible to increase the proportion of semiconductor chips included in the first wiring board, increasing its packaging density. At the same time, it is possible to provide the first wiring board with the necessary mechanical strength and maintain a constant yield of good products in the manufacturing process, which increases the difficulty in the process of three-dimensionally mounted multi-chip modules. There are various excellent effects such as improving the packaging density without increasing the cost.

[Brief explanation of drawings]

FIGS. 1 a, b, c, and d are schematic perspective views, front views, side views, and a detailed view of part A thereof showing one embodiment of the semiconductor device according to the present invention, and FIGS. 2 a, b, and c are conventional examples. They are a schematic perspective view, a side view, and a detailed view of part B thereof. 1... Semiconductor chip, 2... First wiring board, 3
...Second wiring board, 4...Insulating substrate, 5a...Bump, 5b...Electrode (bump), 6...Wire,
7...External connection electrode.

Claims (1)

[Claims] 1. A plurality of semiconductor chips, a plurality of first wiring boards formed by mounting these plurality of semiconductor chips on a substrate surface, and a substrate surface on which these first wiring boards are arranged in an upright state in parallel in the stacking direction. at least one second wiring board disposed perpendicularly to the first wiring board; and an insulating board having external connection electrodes on which the second wiring board is mounted and fixed; 1. A semiconductor device characterized in that the semiconductor chips are mounted in parallel with each other in the stacking direction so that their main surfaces intersect with the substrate surface of the first wiring board.