JPH0851180A - Semiconductor device - Google Patents

Abstract

PURPOSE:To increase packaging densiy while stabilizing the state of the mounting of a semiconductor chip and simplifying an assembly process. CONSTITUTION:Each memory chip 2 of a memory module 1, in which a plurality of the memory chips 2 are loaded on an internal circuit board 6 and sealed by a sealing cap 4, is mounted vertically to the internal circuit board 6 through sockets 3. Accordingly, the mounting of semiconductor chips in a semiconductor device in high-density packaging can be stabilized and the assembly of the semiconductor chips is simplified, and yield and reliability are also improved.

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 more particularly to a memory module having a plurality of memory ICs mounted on one substrate, or a plurality of semiconductor chips mounted on a single package. Hybrid I
It is effectively used for C and multi-chip modules.

[0002]

2. Description of the Related Art In recent years, with the high integration of semiconductor devices,
Memory modules and multi-chip modules in which a plurality of semiconductor devices are combined on one circuit board are becoming smaller and smaller. For example, a memory module in which a plurality of memory ICs are mounted on one circuit board is reduced year by year, and a single in-line memory module as described in JP-A-60-72049 is predominant.

FIG. 7 shows an overall view of a single in-line memory module. In the memory module 25, a plurality of (for example, nine) memory ICs 26 each sealed with a resin or the like are mounted on a circuit board 27 made of glass epoxy, ceramics, or the like. On the circuit board 27, a plurality of contacts 28 for connecting to an external circuit are provided side by side in a line. DRAM is mainly used as the memory IC.

Regarding the multi-chip module, for example, in Japanese Unexamined Patent Publication No. 62-260352, mounting density is improved by mounting a plurality of semiconductor chips on one circuit board vertically to the board. The disclosed examples are disclosed.

[0005]

In the conventional memory module, since the memory IC sealed with resin or the like is mounted on the circuit board in a plane, it is possible to increase the density of the module unless the package itself is downsized. Can not. Further, because of the planar mounting, the occupied area remains the same even if the package is thinned.

Therefore, as disclosed in Japanese Patent Laid-Open No. 62-260352, when a plurality of semiconductor chips are mounted vertically on a circuit board to improve the mounting density, the semiconductor chips are mounted on the circuit board. It is extremely difficult to connect and fix the semiconductor chip to the substrate, and it is difficult to improve the yield because there is no reliable means for vertically fixing the semiconductor chip.

Therefore, an object of the present invention is to improve the mounting density, to stabilize the mounting state of semiconductor chips, and to simplify the assembly process.

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.

[0009]

The outline of the representative one of the inventions disclosed in the present application will be briefly described as follows. That is, a plurality of semiconductor chips are mounted on an internal circuit board, and the individual semiconductor chips of the semiconductor device, which are sealed together with the internal circuit board, are mounted so as to be perpendicular to the internal circuit board via connection fixing means. To do.

[0010]

Since the individual semiconductor chips are mounted so as to be perpendicular to the internal circuit board via the connecting and fixing means, the mounting state of the semiconductor chips in the high-density mounting semiconductor device can be stabilized and the assembling process can be performed. It can be simplified.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example in which the present invention is applied to a memory module will be described below. FIG. 1 is a cross-sectional view of the memory module 1. The memory module 1 is composed of nine memory chips, eight for normal storage and one for parity check. A plan view of the memory chip 2 is shown in FIG. The memory chip 2 includes a memory circuit section 2a and a plurality of electrode pads 2b. In this embodiment, the memory chip 2 uses the socket 3 for connecting and fixing the chip by inserting one side of the chip. Therefore, the plurality of electrode pads 2b of the memory chip 2 are concentrated on the side on the side where the socket 3 is inserted. In this case, in order to widen the pitch between the pads, a plurality of electrode pads 2b are provided in
They may be arranged in a staggered pattern as shown in. FIG. 3 is a diagram showing a state in which the memory chip 2 is connected and fixed to the socket 3. Leads 3a to be connected to the electrode pads 2b of the memory chip 2 are fixed in the recesses of the socket 3. A conductive brazing agent such as solder or a metal foil such as gold foil is used for the lead 3a, and is formed by using, for example, a multilayer substrate technique or a vapor deposition technique. The socket 3 and the internal circuit board 6 are connected using the bumps 5 made of, for example, solder. The bumps 7 are used to mount the memory module 1 on an external substrate (not shown).

The method of assembling the memory module 1 will be described below. First, as shown in FIG. 4, the memory chip 3 is inserted into the socket 3, and the electrode pad 2b and the lead 3 are inserted.
Connect to a. When solder is used for the leads 3a, the socket 3 in which the memory chip 3 is inserted is heated to melt the solder and ensure the connection. Next, the sockets 3 into which the memory chips 3 have been inserted are mounted on the internal circuit board 6 so as to overlap each other. The bumps 5 are bonded to the socket mounting portion of the internal circuit board 6 in advance. By heating the internal circuit board 6 to near the melting point of the bumps 5 during socket mounting, the socket 3 is It is connected and fixed to the substrate 6. Finally, the entire inner circuit board 6 is sealed with the sealing cap 4.

To mount the completed memory module 1 on an external circuit board, bumps 7 are bonded to the contacts formed on the back surface of the internal circuit board 6, and the mounted on the external circuit board.
Mounting is performed by reflowing the bumps 7.

According to the above assembling method, the memory chip 3
It is possible to manufacture a high-density memory module in which is mounted in a stable form.

Next, an example of mounting a memory chip on an internal circuit board using a lead frame will be described.
FIG. 5 shows a partial cross-sectional view of the memory module 8. The memory chip 9 uses a conventional chip in which the electrode pads 9b are provided on two sides of the chip facing each other, and one end of a lead frame 11 fixed by an insulating tape 10 made of, for example, a polyimide resin is used. The bumps 12 are connected to the electrode pads 9b. The other end of the lead frame 11 is formed at a right angle to the memory chip 9. As a result, the memory chip 9 is attached to the internal circuit board 1
4 can be mounted vertically. Also, lead 1
Since the memory chip 9 is fixed by the tape 1 and the tape 10, the mounting area of the memory chip 9 is only the other end of the lead frame 11 formed at a right angle, so that the pitch between the mounting chips can be shortened. It is possible to increase the density and capacity of the memory module.

The method of assembling the memory module 8 will be described below. First, the bump 12 is bonded to the electrode pad of the memory chip 9. Bump bonding
For example, a wire made of solder is used, and a ball is formed on the tip of the wire that has passed through the capillary by electric discharge, and the ball is bonded to an electrode pad in the same manner as wire bonding. The wire is then cut leaving only the ball on the electrode pad to form the next ball. By repeating these operations, the bumps 12 are formed on the memory chip 9. Next, one end of the lead frame 11 which is previously adhered to the tape 10 and the electrode pad 9b of the memory chip 9 are connected by the bump 12. At this time, if the surface of the memory chip 9 and the lead frame 11 are bonded to each other with an adhesive tape or the like, the bonded state is further stabilized. A normal wire bonding may be used for the electrical connection between the memory chip 9 and the lead frame 11. Incidentally, the tape 10
The other end of the lead frame 11 to which is bonded is formed at a right angle before the memory chip 9 is bonded. The memory chip 9 connected and fixed to the lead frame 11 is mounted vertically to the internal circuit board 14 by adhering the other end of the lead frame 11 formed at a right angle to the heated internal circuit board 14. To be done. The bumps 13 are used to connect the internal circuit board 14 and the lead frame 11. The bump 13 is bonded to the other end of the lead frame 11 or the internal circuit board 14 in advance. After mounting a predetermined number of the memory chips 9 on the internal circuit board 14, the mounting portion of the memory chips 9 is sealed by the sealing cap 15 to complete the memory module 8.

According to the above assembling method, a high density memory module can be easily manufactured without changing the positions of the electrode pads of the memory chip.

The effects of the present invention will be described below.

(1) A plurality of semiconductor chips are mounted on an internal circuit board, and the individual semiconductor chips of a semiconductor device, in which the internal circuit board is sealed, are mounted vertically on the internal circuit board. The packaging density of semiconductor chips on the substrate can be improved.

(2) Since the mounting density of semiconductor chips on the internal circuit board is improved, it is possible to reduce the size of a large-capacity semiconductor device.

(3) Since the individual semiconductor chips are mounted via the connecting and fixing means, it is possible to simplify the assembly of the high-density mounted semiconductor device.

(4) Since the individual semiconductor chips are mounted through the connection fixing means, the mounting of the semiconductor chips in high density mounting can be stabilized, and the yield and reliability are improved.

The invention made by the inventor of the present invention has been specifically described based on the embodiments. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say. For example, in the embodiment of FIG. 1 described above, one chip was mounted in one socket, but as shown in FIG. It can also be mounted in the socket 20. In this case, the packaging density can be further improved. Also,
The mounting of the memory module on the external circuit board is not limited to the mounting method using bumps, and a lead pin insertion method or another surface mounting method may be used.

The present invention is not limited to a memory module, but can be applied to a multi-chip module or any other semiconductor device mounted product, and has a particular effect in improving the mounting density. .

[0025]

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

That is, a plurality of semiconductor chips are mounted on the internal circuit board, and the individual semiconductor chips of the semiconductor device, which are sealed together with the internal circuit board, are perpendicular to the internal circuit board via the connection fixing means. By mounting in this manner, it is possible to simplify the assembly in a high-density mounted semiconductor device and stabilize the mounting of semiconductor chips, and the yield and reliability are improved.

[0027]

[Brief description of drawings]

FIG. 1 is a sectional view of a memory module 1 according to an embodiment of the present invention.

2 is a plan view of a memory chip 2 used in the memory module 1. FIG.

FIG. 3 is a diagram showing a state in which a memory chip 2 is connected and fixed to a socket 3.

FIG. 4 is a diagram showing a method of inserting the memory chip 2 into the socket 3.

FIG. 5 is a memory module 8 according to another embodiment of the present invention.
It is a figure which shows the partial cross section figure.

FIG. 6 is a sectional view of a module 16 according to another embodiment of the present invention.

FIG. 7 is an overall view of a conventional memory module.

[Explanation of symbols]

1 ... Memory module, 2 ... Memory chip, 2a ...
... memory circuit section, 2b ... electrode pad, 3 ... socket, 3a ... lead, 4 ... sealing cap, 5 ... bump, 6 ... internal circuit board, 7 ... bump, 8 ... memory module , 9 ... Memory chip, 10 ... Tape, 1
1 ... Lead, 12 ... Bump, 13 ... Bump, 14
...... Internal circuit board, 15 …… Seal cap, 16 …… Bump, 17 …… Module, 18, 19 …… Chip, 2
0 ... Socket, 21 ... Bump, 22 ... Sealing cap, 23 ... Internal circuit board, 24 ... Bump, 25 ...
Memory module, 26 ... Memory IC, 27 ... Circuit board, 28 ... Contact,

Claims (8)

[Claims] 1. A semiconductor device comprising a plurality of semiconductor chips mounted on an internal circuit board and sealed together with the internal circuit board, wherein each semiconductor chip electrode has one side out of four sides of a peripheral portion. A socket which is centrally arranged on the side and which leads the electrode of the semiconductor chip to the outside by inserting one side on which the electrode of the semiconductor chip is arranged,
A semiconductor device, wherein the socket is connected and fixed to the internal circuit board so that the semiconductor chip is perpendicular to the internal circuit board. 2. The semiconductor device according to claim 1, wherein the semiconductor chip is a semiconductor memory device. 3. The semiconductor device according to claim 1, wherein the socket and the internal circuit board are connected by a bump. 4. The semiconductor device is mounted on an external circuit board by means of bumps.
Or the semiconductor device according to 3. 5. A lead frame in which a plurality of semiconductor chips are mounted on an internal circuit board and are sealed together with the internal circuit board, wherein electrodes of each of the semiconductor chips are fixed by an insulating tape. And a lead frame connected to and fixed to the internal circuit board such that the semiconductor chip is perpendicular to the internal circuit board. 6. The semiconductor device according to claim 5, wherein the semiconductor chip is a semiconductor memory device. 7. The semiconductor chip and the lead frame,
6. The bumps are used to connect the lead frame and the internal circuit board.
13. The semiconductor device according to claim 1. 8. The semiconductor device according to claim 5, wherein the connection portion of the lead frame with the internal circuit board is formed substantially perpendicular to the semiconductor chip.