JPH06326151A - Mounting structure of circuit component - Google Patents

Abstract

PURPOSE:To provide the mounting structure, which requires no facility introduction on a large scale and can be mounted and dismantled simply in a short time and in which shock resistance and the effect of heat dissipation are improved, unnecessary radiation is reduced and the deterioration, etc., of performance due to moisture, etc., can be prevented, of a circuit component. CONSTITUTION:An LSI module, in which connecting terminals are aligned previously, is fixed temporarily to a wiring board 5 by an adhesive member 4 such as a double-side tape, and a pushing member 8 having elasticity is installed, and covered with a covering member 9. An engaging piece 10 for mounting is inserted into through-holes 7 for mounting, the covering member 9 is pushed in the direction of the wiring board 5, and the engaging piece 10 is caulked and fixed, thus pushing a flexible substrate 2 by the projecting sections 13 of the pushing member 8, then mutually connecting connecting terminals.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a substrate arranged inside an information processing device such as a computer, a word processor, an electronic cash register, an information processing terminal device, or the like, so-called T.
AB (Tape Automated Bonding) type LSI (Large S)
The present invention relates to a circuit component mounting structure that is preferably implemented when mounting a cale integrated circuit module, and more particularly to a circuit component mounting structure that requires heat resistance, radiation noise resistance, shock resistance, moisture resistance, and removal maintenance.

[0002]

2. Description of the Related Art FIG. 9 is a sectional view showing the structure of a TAB type LSI module. The TAB type LSI module 1 is a circuit component in which the connection terminal 24 of the LSI chip 3 and the terminal 18 of the tape carrier 17 are connected with solder 19 and a resin 20 is coated around the connection. The tape carrier is one in which a plurality of connecting terminals made of a conductive material are formed on one surface of a flexible substrate made of an insulating material.

The TAB type LSI module 1 is mounted on the wiring board 5 by soldering the connection terminals by a reflow method or the like, or connecting the connection terminals with a thermally anisotropic conductive film 21 as shown in FIG. It is realized by doing.

The thermally anisotropic conductive film 21 is formed of a thermoplastic adhesive 21 containing metal particles 22 and the like, and the thermoplastic adhesive 21 is melted by heating and pressurizing, and at the same time, the inside of the adhesive 21 is melted. The metal particles 22 contact the upper and lower connection terminals 18 and 23 to electrically connect the connection terminals,
Moreover, the substrates are adhered to each other by curing the adhesive 21. A typical example is “Anisolm” manufactured by Hitachi Chemical Co., Ltd.

[0005]

The mounting structure of the above-mentioned TAB type LSI module on the wiring board has the following problems.

A large-scale installation of equipment is required for a reflow device for soldering and a thermocompression bonding device for connecting terminals with a thermally anisotropic conductive film.

[0007] Once the terminals of the LSI module and the terminals of the wiring board are connected, the solder or the thermally anisotropic conductive film at the connection site must be melted when the LSI module is removed. Is a factor that hinders the efficiency of the.

The connection terminal is formed in a unit width of several tens to several hundreds μm and a terminal thickness of several tens to several tens μm, and is fixed to the wiring board by a thermally anisotropic conductive film having no elasticity or solder. Therefore, there is a brittle portion near the fixed portion of the connection terminal, and the impact resistance tends to be weak.

Further, since the shield surrounding the LSI chip is not formed, no local countermeasure is taken against unwanted radiation noise. Further, since there is a space around the LSI chip, the moisture-proof measure is insufficient, and problems such as corrosion of the connection terminals over time and deterioration of reliability due to intrusion of moisture into the LSI chip are likely to occur.

Further, in the conventional mounting structure, only the terminal connection is made, and no measures are taken against the heat generated from the LSI. Therefore, sufficient heat is not released,
This may cause various troubles such as deterioration of LSI reliability. In particular, as the LSI is highly integrated, the amount of heat generated tends to increase, and heat dissipation measures are an important issue.

An example of heat dissipation measures is disclosed in Japanese Patent Laid-Open No. 3-3661.
5, JP-A-64-61937, JP-A-1-156594
Is disclosed in. However, JP-A-3-3661
5 is a measure for simplification of installation / removal and shock /
Moisture measures are not taken. Also, JP-A-64-6193
Since the space occupied by the heat radiating member is larger than that of the LSI chip in both No. 7 and 1-156594, it hinders the miniaturization of the device and the measures against shock and moisture are insufficient.

The object of the present invention is to install and remove the circuit parts easily and in a short time without the need for introducing large-scale equipment, to improve the impact resistance of the LSI chip, and to generate it from the LSI chip. It is an object of the present invention to provide a mounting structure of circuit components having a good heat dissipation effect by blocking unnecessary radiation, preventing the performance deterioration of the LSI caused by the invasion of moisture.

[0013]

According to the present invention, an LSI chip is fixed on one surface side of a flexible substrate, and the L chip is formed on the other surface.
A circuit component having a plurality of first connection terminals connected to the SI chip and a wiring board having a plurality of second connection terminals are connected to each other by connecting the first and second connection terminals to each other. In the mounting structure of the circuit component to be fixed, the cover member that covers the circuit component and is detachably provided on the wiring board, and the pressing member that is interposed between the circuit component and the covering member, The member is a circuit component mounting structure, characterized in that when the covering member is mounted on the wiring board, the member is pressed toward the wiring board.

Further, the present invention is characterized in that each of the covering member and the pressing member is made of a material having a relatively good thermal conductivity.

Further, the present invention is characterized in that the covering member has conductivity.

Furthermore, the present invention is characterized in that a heat dissipation member is arranged on the outer surface of the covering member.

Furthermore, the present invention is characterized in that a cooling element is interposed between the covering member and the heat radiating member.

[0018]

According to the present invention, the first connecting terminal of the circuit component and the second connecting terminal formed on the wiring board are aligned with each other, the pressing member is arranged on the outer surface of the circuit component, and the pressing member is further pressed. The covering member is arranged so as to cover the member and the circuit component, and is pressed toward the wiring board to mount the covering member on the wiring board. Therefore, the circuit component is fixed on the wiring board while being pressed by the pressing member and the covering member.
The connection terminal of the circuit component and the connection terminal of the wiring board are pressed and contacted by the pressing member to be electrically connected.

Further, according to the present invention, the covering member and the pressing member are each made of a material having a relatively good thermal conductivity. Therefore, the heat generated from the LSI is efficiently transferred from the pressing member to the covering member and is radiated.

Further according to the invention, the covering member comprises:
It is made of an electrically conductive material. Therefore, the shield is realized by connecting the covering member to the ground wiring of the wiring board, and the noise caused by the unnecessary radiation generated from the LSI can be reduced.

Further, according to the invention, a heat dissipation member made of a material having a relatively good thermal conductivity, for example, aluminum is attached to the outer surface of the covering member. Therefore, the heat transferred to the covering member can be radiated more efficiently.

Further according to the invention, a cooling element is interposed between the covering member and the heat dissipation member. By forcibly cooling using the cooling element, heat dissipation that is higher than natural heat dissipation by the heat dissipation member is realized.

[0023]

1 is a sectional view showing a mounting structure according to a first embodiment of the present invention, and FIG. 2 is an exploded perspective view thereof. The LSI module 1 which is a circuit component is formed by fixing the flexible substrate 2 around the LSI chip 3. The LSI chip 3 is projected and fixed to one surface side of the flexible substrate 2. On the other surface of the flexible substrate 2, a plurality of connection terminal portions 2a, 2b, 2c, 2d connected to the LSI chip 3 are formed. The connection terminal portion means a portion where a plurality of connection terminals are formed, and is shown by hatching in the drawing.

In the LSI module 1, the LSI chip 3 is fixed on the wiring board 5 with an adhesive member 4 such as a double-sided tape, and the flexible substrate 2 is directed toward the wiring board 5 by the convex portion 13 of the pressing member 8. Pressed. On the wiring board 5,
A plurality of connection terminal portions 6a, 6b, 6c, 6d are formed and shown by hatching in the drawing. Therefore, the connection terminal portions 2a to 2d are connected to the connection terminal portions 6a to 6d, respectively.

The pressing member 8 is made of an elastic material and is pressed toward the wiring board 5 by mounting the covering member 9 on the wiring board 5. The covering member 9 is fixed, for example, by inserting and caulking an attachment locking piece 10 into an attachment through hole 7 formed in the wiring board 5. Therefore, when the covering member 9 is removed from the wiring board 5, the pressing of the flexible board 2 by the pressing member 8 is released.

Next, the mounting procedure of the LSI module 1 will be described. The connection terminal portions (outer leads) 2a, 2b, 2c, 2d of the LSI module 1 and the connection terminal portions 6a, 6b, 6c, 6d formed on one surface of the wiring board 5 are aligned in correspondence with each other, Temporarily fix with the double-sided tape 4 for temporary fixing. The depression 12 of the pressing member 8 is arranged so as to contact the outer surface of the LSI chip 3 of the LSI module 1, and the covering member 9 is arranged so as to cover them. The covering member 9 is composed of a main body 9a and a plurality of mounting portions 9b. The main body 9a is formed in a relatively flat rectangular parallelepiped box shape, and one side surface of the pair of side surfaces having the largest area is open.

The covering member 9 is pressed toward the wiring board 5 and is attached to the attachment through hole 7 for attachment.
The wiring board 5 is mounted by caulking. The elastic force of the pressing member 8 acts on the covering member 9 in a direction away from the wiring board 5, and the locking piece 10 abuts on the wiring board 5. Therefore, a good mounting state can always be obtained without displacement or rattling. Further, by the pressing action of the convex portion 13 of the pressing member 8, the connection terminal portions 2a to 2d of the LSI module 1 are always connected while being pressed by the connection terminal portions 6a to 6d formed on one surface of the wiring board 5. To be done.

FIG. 3 is a sectional view of the pressing member 8. The pressing member 10 is formed in a relatively flat rectangular parallelepiped shape, and the concave portion 12 is formed in the substantially central portion of one surface of the pressing member 10, so that the peripheral portion of the concave portion 12 becomes the convex portion 13. The LSI chip 3 fits in the recess 12. This can reduce the pressure applied to the LSI chip 3 when the cover member 9 is pressed and fixed.

FIG. 4 is a side view of the vicinity of the mounting portion 9b of the covering member 9. The mounting portion 9b includes a mounting locking piece 10 and a step portion 11. The attachment locking pieces 10 are provided at substantially central portions of the four sides of the main body 9a of the covering member 9 on the opening side, and are formed in a hook shape. A step portion 11 is provided on the main body 9a side of the mounting portion 9b. This is because when the covering member 9 is pressed and fixed, the wiring board 5 and the main body 9a are
This is because the contact with the wiring board 5 is minimized and other wirings (not shown) on the wiring board 5 are not damaged.

As described above, according to this embodiment, when the LSI module 1 is attached or detached for service maintenance or the like, the attachment locking piece 10 is caulked or released by using a jig (before bending It can be done easily and in a short time. Since the impact of the pressing member 8 on the LSI module 1 can be absorbed by the cushioning action, the impact resistance of the LSI chip 3 is improved. Further, since the LSI module 1 is fixed in a state of being in close contact with the pressing member 8, it is possible to block intrusion of moisture and fine dust.

Next, a second embodiment of the present invention will be described. Since the second embodiment has the same structure as in FIGS. 1 and 2, the same reference numerals are used for the same constituent members. In this embodiment, the pressing member 8 is characterized by being made of a high heat conductive rubber material or a liquid heat sink material made of a composite material such as silicon, and the covering member 9 is made of aluminum or alumina, for example. It is characterized by having high thermal conductivity. As the liquid heat sink material, for example, "Fluorinert" manufactured by Sumitomo 3M Limited is used.

The heat generated from the LSI chip 3 is efficiently transmitted from the pressing member 8 having high thermal conductivity to the covering member 9 and radiated from the covering member 9 to the outside.

As described above, according to this embodiment, a good heat dissipation effect can be obtained in addition to the effects of the first embodiment described above.

Next, a third embodiment of the present invention will be described. Since the third embodiment has the same structure as that of FIGS. 1 and 2, the same reference numerals are used for the same constituent members. In this embodiment, the covering member 9 is made of, for example, aluminum, and is characterized by having conductivity and radio wave absorption / reflection characteristics. Since the covering member 9 can be connected to the ground wiring of the wiring board with low impedance, shielding is realized.

As described above, according to this embodiment, in addition to the effects of the first and second embodiments described above, the noise caused by unnecessary radiation generated from the LSI chip 3 is reduced, and the EMI is reduced.
The shield effect is improved.

FIG. 5 is a sectional view showing a mounting structure according to a fourth embodiment of the present invention, and FIG. 6 is an exploded perspective view thereof. This embodiment has the same structure as the first to third embodiments described above, and the same constituent members are designated by the same reference numerals. The feature of this embodiment is that the heat dissipation member 14 is installed on the outer surface of the covering member 9 via the high thermal conductive adhesive 15. The high thermal conductive adhesive 15 is obtained by kneading aluminum powder with a two-component epoxy adhesive, for example. The heat dissipation member 14 is formed of a heat sink material such as aluminum having a good thermal conductivity. One surface of the heat dissipation member 14 is formed flat, and a plurality of irregularities is formed on the opposite surface.

The heat generated from the LSI chip 3 is transferred from the pressing member 8 to the covering member 9 and further to the heat radiating member 14 via the high thermal conductive adhesive 15. The heat radiating member 14 has a large number of irregularities to increase the surface area and enhances the heat radiating effect, so that heat is efficiently radiated.

Also in this embodiment, the same effects as those of the above-mentioned first to third embodiments can be obtained. Further, the heat dissipation effect is improved as compared with the second embodiment.

FIG. 7 is a sectional view of a mounting structure according to a fifth embodiment of the present invention, and FIG. 8 is an exploded perspective view thereof. This embodiment has the same structure as the above-mentioned first to fourth embodiments,
The same components are designated by the same reference numerals. In this mounting structure, the cooling element 16 is arranged on the outer side surface of the covering member 9 via the high thermal conductive adhesive 15, and the heat dissipation member 14 is placed on the outer side surface of the cooling element 16 via the adhesive 15. It is characterized by being installed. For the cooling element 16, for example, a Peltier element is used. The covering member 9 to which the heat is transferred is cooled by the cooling element 16, and the residual heat is transferred to the heat dissipation member 14,
Heat is dissipated.

Also in this embodiment, the same effects as those of the above-mentioned first to fourth embodiments can be obtained. Further, the heat radiation effect is improved as compared with the second to fourth embodiments.

[0041]

As described above, according to the present invention, the circuit parts can be easily attached and detached in a short time, and it is not necessary to introduce large-scale equipment. Also L
It is possible to reduce the impact on the SI chip, prevent corrosion of the connection terminals due to moisture, etc., and prevent the reliability of the LSI chip from degrading, further improving the heat dissipation effect, and EM against unwanted radiation.
It is possible to improve the I (Electromagnetic Interference) shielding effect.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a circuit component mounting structure that is a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the mounting structure shown in FIG.

FIG. 3 is a cross-sectional view of a pressing member 8.

FIG. 4 is a side view of the vicinity of a mounting portion 9b of the covering member 9.

FIG. 5 is a cross-sectional view of a circuit component mounting structure according to a fourth embodiment of the present invention.

6 is an exploded perspective view of the mounting structure shown in FIG.

FIG. 7 is a cross-sectional view of a circuit component mounting structure according to a fifth embodiment of the present invention.

8 is an exploded perspective view of the mounting structure shown in FIG.

FIG. 9 is a cross-sectional view of a TAB type LSI module.

[Explanation of symbols]

1 TAB type LSI module 2a, 2b, 2c, 2d Connection terminal part (outer lead) 3 LSI chip 4 Adhesive member 5 Wiring board 6a, 6b, 6c, 6d Connection terminal part 7 Mounting through hole 8 Pressing member 9 Covering member 9a Main body 9b Mounting part 10 Locking piece for mounting 11 Step part 12 Recessed part 13 Convex part 14 Heat dissipation member 15 Adhesive 16 Cooling element

Claims (5)

[Claims] 1. A circuit component in which an LSI chip is fixed on one surface side of a flexible substrate, and a plurality of first connection terminals connected to the LSI chip are formed on the other surface, and a plurality of second component parts. In a mounting structure of a circuit component for connecting and fixing a first and a second connection terminal to a wiring board on which a connection terminal is formed, a covering member that covers the circuit component and is detachably provided on the wiring board. And a pressing member interposed between the circuit component and the covering member, wherein the pressing member is pressed in the wiring board direction when the covering member is mounted on the wiring board. The mounting structure of the circuit component. 2. The mounting structure for a circuit component according to claim 1, wherein each of the covering member and the pressing member is made of a material having a relatively good thermal conductivity. 3. The mounting structure for a circuit component according to claim 2, wherein the covering member has conductivity. 4. The mounting structure for a circuit component according to claim 2, wherein a heat dissipation member is arranged on an outer surface of the covering member. 5. The circuit component mounting structure according to claim 4, wherein a cooling element is interposed between the covering member and the heat dissipation member.