JPS6398139A - Manufacture of pin grid array - Google Patents

Abstract

PURPOSE:To simultaneously set a plurality of circuit units at a plurality of cavities by continuing many circuit units through a connector, respectively setting the units in the continued state in the cavities and injection molding them in the cavities with synthetic resin. CONSTITUTION:Many circuit units 4, 4,... are continued through a connector 6, respectively sets a plurality of cavities 2, 2,... in the continued state, and injection molded in the cavities 2 with synthetic resin. Thus, it is not necessary to position the units 4, 4,... individually in the cavities 2, 2,... Thus, an accurate set of the units 4, 4,... to the cavities 2, 2,... is facilitated to obtain a forming method for a pin grid array having an excellent production efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for manufacturing a pin grid array of a molded product in an IC puff case or the like.

[Background technology] Increasing the functionality of elements in semiconductor packages such as ICs,
In response to the increase in the number of I10s associated with higher densities and the shorter lead lengths associated with higher speeds, pin grid arrays (PGA ) has been put into practical use. This pin grid array uses the entire back surface of the board to protrude a large number of pins, and by inserting the pins into sockets or through holes provided on the device's mounting board (motherboard), you can connect the pins to the motherboard. It can be installed to.

As for the material of the substrate, attempts have been made to use a printed wiring board obtained from υ (fat laminated board) as the substrate in response to lower prices.

That is, as shown in FIG. 6, the substrate 5 has a thickness of 1°0ff.
A conductive circuit 17 is provided on the surface of the substrate 5, and pin holes 13 are drilled in the substrate 5 using a drill or the like. The head 14 of the pin hole 13
A large number of pins 3 are fixed in a protruding state from the substrate 5 by being press-fitted into the substrate 5, thereby creating a pin grid array Δ. In FIG. 6, reference numeral 15 indicates each pin 3 for positioning the press-fitting depth of the head 14 of the pin 3 into the board 5.
A protruding collar 16 is a collar provided on some of the pins 3 to position the insertion depth of the pins 3 when attaching to the motherboard. However, in this case, the pin hole 13 is inserted into the board 5 for attaching the pin 3.
This requires a process of machining the pin 3 into the pin hole 13 and press-fitting the pin 3 into the pin hole 13, which increases the number of man-hours and limits the strength of press-fitting the pin 3 into the board 5 due to cracks in the board 5. Therefore, there are problems such as not being able to obtain sufficient pull-out strength for the pin 3.

Therefore, the present inventors have devised a method of creating a pin grid array using a molded product. That is, a pin grid array is created by forming a board by molding R&R and resin, inserting the bases of the pins into the board during this molding, and insert-molding a circuit body provided with a conductive circuit into the board. Create it. With this type, when the board is molded with synthetic resin, the base of the pin is inserted into the board and the pin is fixed to the board, so it does not require man-hours such as drilling pin holes and press-fitting the pins. By attaching the pin easily, it will not come off and the pull-out strength will not become unstable, which is the case when the pin is press-fitted. In order to manufacture a pin grid array by molding in this way, the circuit body is set in the cavity of the molding die with the pins connected to each other.
After this, synthetic resin is injected into the cavity and allowed to harden or solidify, but in order to mold a large number of pin grid arrays in one injection of synthetic resin,
Molding is performed by forming a large number of cavities in a molding die, setting a pin and a circuit body in each cavity, and injecting synthetic resin into each cavity at the same time. However, when performing molding in this way, it is easy to set pins in the cavity at accurate positions by providing pin insertion holes in the molding die, but it is difficult to set the circuit body in the cavity. It is necessary to perform this while aligning the connections with the pins, and setting the circuit body while adjusting the position one by one in each of the many cavities requires a great deal of effort and reduces production efficiency. It was something like that.

[Objective of the Invention 1] The present invention has been made in view of the above points, and provides a pin grid array that allows accurate setting of circuit bodies in each cavity portion and has excellent production efficiency. !
i! The purpose is to provide a method for manufacturing.

[Disclosure of the Invention] According to the method for manufacturing a pin grid array according to the present invention, the pins 3 are set in the cavity part 2 of the molding die 1, and a synthetic resin is applied to the bit part 2 connected to the base of the pin 3. When manufacturing a pin grid array in which the bases of the pins 3 and the circuit body 4 are embedded in the substrate 5 formed of a synthetic resin molded product by injection molding, a large number of circuits are connected via the connection part 6. The circuit bodies 4, 4... are made to be continuous, and each circuit body 4, 4... is set in a plurality of cavities 2, 2... in this continuous state, and the synthetic resin is poured into the cavity part 2. It is characterized by injection molding, in which a large number of circuit bodies 4, 4... are placed in a row in each of the plurality of cavity parts 2, 2..., respectively. By setting the circuit bodies 4, 4... individually in each cavity part 2, 2...
The present invention will be described in detail below with reference to Examples.

Figure 14 (of course not shown to scale) shows an embodiment of the pin grid array A manufactured according to the present invention, in which the substrate 5 is a plate formed from a synthetic resin molding material by injection molding, transfer molding, etc. When forming 5, pin 3
A large number of pins 3 are attached to the board 5 in parallel by insert molding so that the base of the circuit body 4 is embedded in the board 5, and the circuit body 4 is embedded in the board 5 while connected to the base of the pins 3. It is installation. The synthetic resins used for purchasing the substrate 5 include thermosetting resins such as 7-enol, epoxy, silicone, and polyimide, and polyphenylene resins.
Thermoplastic resins such as Aito, Forisal 7one, polyether sulfone, and polyarylsulfone can be used. Based on actual results, it is preferable to use epoxy resins in terms of reliability, and the latter thermoplastic resins in terms of flexibility, mechanical strength, and heat resistance.

The circuit body 4 can be formed by providing a radial conductive circuit 17 on an insulator 22, such as a lath epoxy wiring board, a plus polyimide wiring board, a glass Teflon wiring board, a polyester wiring sheet or film,
A polyimide wiring film or sheet can be used, but it is also possible to use copper, aluminum, 42 alloy (Ni-F with 42% Ni) fixed with a polyimide film, etc.
It is also possible to use a lead frame made of (e-alloy) as the circuit body 4. The center portion of the circuit body 4 serves as a space 12 for mounting a semiconductor chip 8 such as an IC chip, and the end portion of the conductive circuit 5 close to the space 12 serves as an inner lead g7. Furthermore, a pin hole 34 is bored in the circuit body 4 at the land portion of the conductive circuit 17 at a position corresponding to the pin 2. Here, as shown in FIG. 5(a), each circuit body 4 is integrally connected by a connecting part 6 in which an insulator 22 is extended, and a large number of circuit bodies 4, 4, etc. are connected in a band-like manner. If the thickness of the circuit body 4 is 0.11Il1 or more, a width is provided at the boundary between the connection part 6 and each circuit body 4 at the portion of the insulator 22, as shown in FIG. 5(b). A V-shaped cut is provided in the direction to facilitate separation.I) A release portion 38 is formed. On the other hand, the pin 3 is formed to have a circular cross section over the entire length in the axial direction, and a circular collar 11 is provided at the base serving as the head, which protrudes from the entire circumference of the pin 3. A similarly circular flange 21 is provided below the flange 11.

When molding the substrate 5, the pins 3 are inserted and set into the pin insertion holes 18 provided in the lower mold 1a of the molding die 1, as shown in FIG.

At this time, the lower flange 21 of the pin 3 is locked to the upper surface of the peripheral edge of the pin insertion hole 18, and the insertion depth of the pin 3 into the pin insertion hole 18 is determined, and the pin insertion hole 18 is inserted into the flange. 21, the opening 1 is closed.

Since the pin 3 can be set by inserting the pin 3 into the pin insertion hole 18 in this way, it can be done accurately and easily. Then, by inserting the upper end of the pin 3 into the pin hole 34 and locking the periphery of the pin hole 34 with the upper collar 11 of the pin 3, the circuit body 4 is held in the lower mold 1a while connected to the pin 3. and set it.

Therefore, when setting the circuit body 4, it is necessary to align each pin hole 34, 34, . . . of the circuit body 4 with each pin 3.3, . Here, a plurality of cavities 81S 2 , 2 . . . are formed in the molding die 1 for multi-cavity molding, and in each cavity portion 2 , 2 . It is necessary to set the circuit body 4 with the circuit bodies 34 aligned, but each circuit body 4, 4... is continuous in a band shape by the connection part 6, so it is difficult to adjust the dimensions of the connection part 6. By setting the spacing between the circuit bodies 4, 4, . Pin 3 and each circuit body 4,
4... are aligned with the pin holes 34, and in each cavity part 2, 2..., the pins 3 and pin holes 3 are aligned.
4 without the need for alignment with multiple circuit bodies 4.
, 4... at the same time in the cavity parts 2, 2...
・It can be set to increase production efficiency.

The pins 3 can be easily set by inserting them into the pin insertion holes 18, so even if there are a large number of cavities 2, it will not be difficult to assemble the set.

A support 39 is set in the center of the mold 1a, and a space 12 for the circuit body 4 is provided on the upper surface of the support 39.
The lower surface of the periphery of the holder is placed on the holder. Support 3
9 is generally made of a heat dissipating material such as a metal such as copper, iron, or aluminum or a ceramic having excellent thermal conductivity. After setting the pin 3 and circuit body 4 in the lower mold 1a in this way, the upper mold 1b and the lower mold 1 of the molding mold 1 are assembled.
The upper mold 1b is provided with molding protrusions 10 protruding from the upper mold 1b corresponding to the positions of the pins 3, and the lower end surface of the molding protrusions 10 is provided with the pins 3. The four parts 32 into which the upper end is inserted are recessed. Therefore, by clamping the mold, the lower end surface of the molding protrusion 10 comes into contact with the upper surface of the periphery of the pin hole 34 of the circuit body 4 with the upper end of the pin 3 inserted into the four parts 32, and the circuit body 4 is molded. Protrusion 10 and collar 1 of pin 3
1 and fixed. Further, a presser core portion 35 is provided in a protruding manner on the upper mold 1b of the molding die 1, and a stepped surface 36 is recessed in the peripheral edge of the lower surface of the presser core portion 35. Then, by clamping the mold, a space 1 of the circuit body 4 is formed between the holding core part 35 and the support body 39.
The peripheral edge of the conductive circuit 17 of the circuit body 4 is brought into close contact with the surface of the inner lead portion 7 of the conductive circuit 17 of the circuit body 4. In this state, by injecting the resin molding material into the molding die 1 and curing or solidifying it, the circuit body 4 is insert-molded into the substrate 5 at the same time as the substrate 5 is molded within the molding die 1, and the circuit body The base of the pin 3 can be insert-molded into the substrate 5 in contact with the conductive circuit 17 of 4. At this time, since the synthetic resin is injected into the molding die 1 while the inner lead $7 of the conductive circuit 17 of the circuit body 4 is pressed by the step surface 36 of the holding core part 35, the inner lead part 7 is injected into the molding die 1. The circuit body 4 can be insert molded into the substrate 5 while being exposed from the substrate 5.

Further, as mentioned above, the circuit body 4 is used in a state in which a large number of circuit bodies 4 are connected in a band shape by the connecting portion 6, and a plurality of circuit bodies 4, 4, etc. are simultaneously placed in a molding die. 1, the connection part 6 is sandwiched between the upper mold 1b and the lower mold 1a between the adjacent cavity parts 2, 2, as shown in FIG. At this time, the circuit body 4 is set so that the disconnection portion 38 between the connecting portion 6 and the circuit body 4 is located on the side of each cavity portion 2, 2, . . . . In this state, a synthetic resin is injected into the molding die 1 and cured or solidified, thereby forming a plurality of substrates 5 connected by the connecting portion 6 as shown in FIG.
, 5... can be molded simultaneously. In each board 5 formed in this way, the cutout portion 3 of the circuit body 4 is
8 is located inside the board 5, and when each circuit body 4 is separated by the cutting part 38, a recessed part 41 will be created on the end surface of the board 5 as shown in FIG. 3(b). However, if the substrate 5 is made of thermoplastic resin, the recessed part 41 is closed by heat-sealing this part, and if the substrate 5 is made of thermosetting resin, it is completely sealed during molding. The concave cutout 41 is closed by heat sealing when recuring after being kept at a level of shaping without being cured. Therefore, as shown in FIG. 3(c), the recessed part 4
1 is closed, the end face of the circuit body 4 is completely embedded in the board 5, which eliminates the need for finishing the end face of the circuit body 4, and prevents moisture and moisture from entering the circuit body 4 from the end face. This means that moisture resistance reliability can be improved by preventing the infiltration of moisture.

When attaching the base of the pin 3 to the substrate 5 by insert molding as described above, the flange 11 provided on the pin 3 is embedded in the substrate 5 as shown in Figure tJfJ4, and the lower surface of the flange 21 is attached to the substrate 5. The base of the pin 3 is firmly held within the substrate 5 by embedding the collar 11.21, thereby increasing the pull-out strength of the pin 3. At the same time, it is possible to prevent the pin 3 from wobbling. Furthermore, the connection between the conductive circuit 17 of the circuit body 4 and the pin 3 is made by connecting the pin 3 to the pin hole 34.
This is done by inserting and contacting the base of the pin hole 34, but in order to ensure this connection, it is preferable to provide through-hole plating on the inner periphery of the pin hole 34. Also, the upper mold 1b of the molding die 1
As shown in FIG. 4, a four part 9 is formed on the substrate 5 by the molding protrusion 10 provided at the pin hole 34 portion of the circuit body 4, exposing the periphery of the pin hole 34 and the upper end of the pin 3. By filling these four parts 9 with conductive materials such as small particles of low-melting metal alloy such as solder, cream solder, conductive paint, conductive face, conductive adhesive, etc., the pin holes 3
The four portions of the conductive circuit 17 and the pin 3 can be joined using a conductive material, and the reliability of the conduction between the conductive circuit 17 and the pin 3 can be improved. In addition, even if the connection part 6 is separated from the circuit body 4 using a jig or the like after molding as described above, other methods may be used when the upper and lower molds 1 a and 1 b of the molding die 1 are clamped. The shearing force automatically causes separation, and the circuit body 4 is attached to the board 5 as described above.
and a large number of pins 3, 3, .
A wire 20 is bonded between the inner lead portion 7 of the conductive circuit 17 of the circuit body 4, and the semiconductor chip 8 and the pins 3 are connected by the circuit body 4 to form a pin grid array A. This one is Uko-shaped! In the pin grid array A, devices can be attached to a mounting board (motherboard) by inserting each pin 3 into a socket or through hole 29 provided on the motherboard 28. At this time, a plurality of positioning protrusions 30 are integrally provided on the board 5 in parallel with the pins 3 and have the same protrusion size, and these positioning protrusions 3
This is so that a space can be formed between the substrate 5 and the motherboard 28 with a predetermined gap by the tip of the 0 coming into contact with the surface of the motherboard 28. Since the space between the substrate 5 and the motherboard 28 is thus formed by the positioning protrusion 30, some of the pins 3 are provided with positioning flanges 16 as shown in the conventional example in FIG. This means that pins 3 having the same shape can all be used. Furthermore, since the positioning protrusions fi30 come into contact with the motherboard 28 in this way, the load applied between the motherboard 28 and the board 5 is supported by the positioning protrusions 30, and deformation of the pins 3 can also be prevented. Here, each positioning protrusion 30 is formed into a molding recess 31 in the molding die 8 as shown in FIG.
By providing these, the ribs that connect the positioning protrusions 30 are formed at the same time as the substrate 5 is molded. If this is done, the substrate 5 can be reinforced by the ribs, and the substrate 5 can be made thinner. Furthermore, the heat generated by the semiconductor chip 8 mounted on the substrate 5 is dissipated by the three supports formed of heat sinks, and at this time, the fourth
In the illustrated embodiment, the semiconductor chip 8 is mounted on the upper surface of the circuit body 4, which is the surface opposite to the surface from which the pins 3 are protruded, but the semiconductor chip 8 is mounted on the lower surface of the circuit body 4. It is also possible to mount the semiconductor chip 8 on the lower surface of the circuit body 4 so that the support 39 is exposed on the upper surface of the substrate 5. As a result, the heat radiated from the support body 39 can be efficiently radiated without being trapped in the gap between the substrate 5 and the motherboard 28.

[Effects of the Invention] As described above, the present invention sets pins in the cavity of a molding die, sets a circuit body in the cavity while connected to the base of the pin, and injects synthetic resin into the cavity. In order to do this, a large number of circuit bodies were connected in series through the connecting parts, and in this continuous state, each circuit body was set in a plurality of cavities, and the synthetic resin was injected into the cavities. , it is necessary to set the circuit bodies aligned with the pins in each of the plurality of cavities, but each circuit body is connected by the connection part, so the interval between the circuit bodies is equal to the interval between the cavities. By setting the same values, by simply aligning the pins in the -m cavity, each circuit body will align with the pins in each of the other cavities, and the pins and circuits will be aligned one by one in each cavity. A plurality of circuit bodies can be set in a plurality of cavities at the same time without the need for alignment with the body, and production efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a molded state in an embodiment of the present invention;
Figure 2 is an enlarged sectional view of a part of the same as above, Figure 3 (a) and (b)
(c) is an enlarged cross-sectional view of the board portion in the molded state as above;
The figure is a cross-sectional view of a pin grid array manufactured by the above method, FIGS. 5(a) and 5(b) are a plan view and an enlarged cross-sectional view of a circuit body used in the manufacture of the same, and FIG. 6 is a cross-sectional view of a conventional example. . 1 is a molding die, 2 is a cavity portion, 3 is a pin, 4 is a circuit body, 5 is a substrate, and 6 is a connection portion. Agent Patent Attorney Ishi 1) Ai 7 Figure 3 Figure 6 Procedural Amendment (Spontaneous) February 6, 1988 To the Commissioner of the Patent Office 2.1, Indication of the Case 1988 Patent [1244453 No. 2, Invention Name: Manufacturing method of pin grid array 3, relationship with the amended case Patent applicant address: 1048 Kadoma, Kadoma City, Osaka Prefecture Name (58
3) Matsushita Electric Works Co., Ltd. Representative Sadao Fujii 4, agent postal code 530 5,? l[I Date of Directive Order 1) The scope of claims on page 1 of Specification 8 is corrected as follows. [(1) A pin is set in the cavity of a molding die, a circuit body connected to the base of the pin is set in the cavity, and a synthetic resin is injected into the cavity to form a synthetic resin molded product. In manufacturing a pin grid array in which the bases of the pins and the circuit bodies are embedded in the substrate to be formed, the circuit bodies are connected to each other through the connecting portions, and each circuit body is connected in this continuous state. A method for manufacturing a pin grid array, characterized in that a synthetic resin is injected into a plurality of cavities, respectively, and molded into the cavities. ”2) Same as fjS, page 6, No. 5
Delete "many sheets" in the row and insert "many sheets". 3) Delete “many sheets” in the 9th line of the same page, and change to “many sheets”
Insert. 4) Delete “Conductive circuit 5” on page 8, line 5 of the above, and add “
Insert “conductive circuit 17”. 5) Same page! @Correct "Pin 2" in line 7 to "Pin 3". 6) Delete "many sheets" and insert "many sheets" in line 11 of the same page as above. 7) Same as above! n 10 'rt, m 13 h eye rf
fl1 sheet” all deleted 1. , insert "multiple". 8) Delete ``1 multiple sheets'' on page 12, line 16 of the same as above, and ``
Insert "Many." 9) On the 17th line of the same page as above, [Delete multiple sheets J and insert "multiple". 10) Delete "1 many sheets" on page 18, line 16 of the same page,
Insert "many". 11) Same as above, page 19 m9? Delete "Multiple photos" on the left side,
Insert "multiple".

Claims (1)

[Claims] (1) Form a synthetic resin molded product by setting a pin in the cavity of a molding die, setting the circuit body in the cavity while connected to the base of the pin, and injecting synthetic resin into the cavity. In manufacturing a pin grid array in which the bases of the pins and the circuit bodies are embedded in the board to be processed, a large number of circuit bodies are connected in series via the connecting parts, and each circuit body is connected to a plurality of circuit bodies in this continuous state. A method for producing a pin grid array, characterized in that each pin grid array is set in a cavity, and a synthetic resin is injected into the cavity.