JPS6152000A - Automatically mounting method of flat package semiconductor element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for automatically soldering and mounting flat packaged semiconductor devices onto printed circuit boards.

[Background technology and its problems]

The flat package fiLsI has a plurality of lead pins protruding from each of two or four sides of the flat package, and these lead pins are usually soldered to a connected portion of a printed circuit board. By the way, conventionally,
There are two methods for this soldering: one is to do it manually using a soldering iron, and the other is to use a square frame-shaped heating plate to press the glue dowels on the two or four sides at the same time. . However, in both cases, positioning and supplying the flat package LSI onto the circuit board was done by hand, and soldering was also done by hand.

However, with the former method of manual soldering, it took an extremely long time to make the U-fitting process, the workability was poor, and the lead pins still floated onto the solder), leading to bridging and poor strength. There were cases where this occurred.

In addition, even with the latter method that uses a heating plate, the feeding position of the flat package is difficult to manually position, and since the heating plate is constantly heated, the flux may seize on the heating plate, which often occurs. It is inefficient in performing fusix removal. Also, since the heating plate is shaped like a square frame, it is necessary to have a way to securely hold the package in advance.)
However, when the heating plate is pressed against the lead pins, it tends to slip off from the connected parts. Furthermore, since the integrally formed frame-shaped heating plate presses down all the solder pins at the same time, it is impossible to press the pins uniformly as a whole, and as a result of the uneven force, the pressing ends up on the solder of the lead pins. The reliability was poor as floating and bridging occurred, and the connection strength was weak at 61 minutes.

[Purpose of the invention]

The present invention has been made with a focus on the above-mentioned 4ft, and is an automatic mounting method for flat packaged semiconductor devices that can efficiently and reliably connect the lead pins of flat packaged semiconductor devices and improve reliability. This is what we offer.

[Summary of the invention]

a step of transporting the printed circuit boards one by one; a step of attaching solder flux 7 on the solder layer that has been laminated in advance on the lead pattern of the printed circuit board transported in the step; and the step. a step of installing a flat package type semiconductor device so that the lead pins of the flat package type semiconductor device are placed on the lead pins attached to the fuses; means for melting and soldering the solder layer by simultaneously heating the lead pin rows on at least one side of a flat package type semiconductor element while being pressed by a heater chip; The present invention provides a self-mounting method for a flat package type semiconductor device, which includes a step of transporting a printed circuit board mounted thereon.

[Embodiments of the invention]

Next, an example will be described in which the method of the present invention is applied to mounting a flat package type IC on a printed circuit board. A magazine (Fig. (not shown), and is configured to be transported one by one by a circuit board discharge loader (2).

This circuit board (1) is conveyed onto a table (3) movable in the X-Y directions. On the other hand, flat package IC
Tray to store (4) IC' (4)
) and place it on the IC positioning section (6). After the center position of the IC (4) is determined by the positioning section (6), the IC (4) is sucked by suction means such as a collet and lifted by the conveyance means (7), and the above-mentioned circuit board is removed.
(1) to the predetermined I'C (4) mounting position.

A printed circuit is formed, but an insulating film is formed on the surface of this printed circuit, so that only the lead pattern (8) of the IC (4) is exposed.

In other words, this lead pattern (8) is connected to the flat package IC (4) of FIG. 2(A), as shown in FIG. 2(B).
) Lead patterns αJα and αυQflG are printed to match the lead pin rows (9) α0 (11) α. This lead pattern α, 3αIQ→α0 has a structure in which a solder layer is transferred. A solder layer is also transferred onto each lead pin (9) (10 (11) 02) of the above IC (2). This /S solder layer is formed only on either the lead pattern or the lead pin. Good too.

In this state) flux is applied relative to the node string (9 α0(n)υ and lead butter 103α/B(1(ie).

For example, the lead pattern α→αa ara in FIG. 2(B)
Stamp solder flux onto IIG using a stamping method.

Of course, the flux may be applied or the flux liquid may be sprayed. The IC positioned by the positioning part (6) on the substrate (1) to which the flux has been attached in this way
(4) is transported by the transport means (7), and the IC (4) is transferred! J
)” 'e: y column (9) (10(Ll) u
Wo! J −)” /< p −yα3 (Ml (i
s (Place the IC in a consistent manner. In this placement state, the IC
The first heating head α is lowered onto the X-direction lead pin rows (9) and (2) of (4), and the pair of heater chips provided at the tips of this head are pressed with a force of, for example, 1~ Press with 4 KF and heat in this pressed state, for example, by applying current for 1 to 3 seconds to melt the solder and carry out the soldering process.At this time, a thermocouple is attached to the heater chip αe. Once installed, the temperature is controlled to a set temperature of, for example, 300 to 350°C.

In this X direction, the heating head aη is
After rising and returning to its original position, move the second heating head α9 above the IC (41) of the circuit board (1), lower it above the lead pin row αO in the Y direction, and install it at the tip of the head α9. A pair of heater chips (7) are used to press the lead pins (7), and in this pressed state, the -.-.-. solder is heated and melted to complete the process of attaching the I-.-.-.

These soldering processes can be done by installing multiple ICs (if there are multiple 41s, heating heads α'7 for each of Alternatively, the X direction may be soldered first, and then the Y direction may be soldered.

The ICs (4) may be sequentially soldered. Of course, even with one IC (4), soldering in the X and Y directions may be performed by transferring the circuit board (1) below the first and second heating heads αη.

The circuit board (1) that has been soldered in this manner is transported and carried into a magazine (not shown) by a board unloader (c). Full automation is achieved by controlling a series of these programs with a microcomputer. When the soldering is completed, the next circuit board (1) is controlled to be carried onto the table (3), thereby establishing a mass production process.

A specific example of the positioning section in the above embodiment is shown in FIG.

301-1: Substrate. At the center of this base (30), six tables are provided on which ICs shown in FIG. 2(A) packaged as electronic components are placed.

Further, the table 0 is provided with a suction port (32a) connected to a suction device (not shown) on its upper surface, which is the mounting surface, so that the table 0 can be supported. On the other hand (33a),
(33b) is 271ifj part style M mechanism-c. All of these have the same structure, and one of them is explained as follows.

In other words, (3φ, [Yes] is an arm that is lined up in parallel at a required interval and has a fixing pin (34a) in the middle part.Then, in these arm diagrams, the middle part between 041 is connected through the hinge Each arm is rotatably supported,
The hinge C is used as the rotating part, and each fixing pin (34a),
(34a) can be used as a fulcrum to open and close. Further, claw bodies (G) and (T) as parts moving bodies are provided protruding inward from the tip sides of each of the arms G and Ω, respectively. And each arm.

G! A coil spring (1) is interposed in a compressed state between the proximal ends of the arms (1), and the distal ends of the arms (2) and (2) are biased in the closing direction by the elastic force of the coil spring (7).

However, the claw portion Q9 can move symmetrically, that is, synchronously, with respect to the approaching and separating directions in response to an external force applied to the arm GLl+31 based on the open state. The component adjustment mechanism (33b) configured in this way has claws (force) arranged on both sides of the table (→) so as to sandwich the IC placed on the table from the X direction. In addition, the component adjustment mechanism (33a) has claw portions 3+'/, G so as to sandwich the IC from the X direction and the xX direction.
Arrange # on both sides of the table Q, and attach the base (to) respectively.
Each fixing pin (34a), (34a) is rotatably supported on the top. However, the two sets of claws Ue
.

On the other hand, CyJ uses a hydraulic cylinder as a driving mechanism. Then, the piston (38
a) At the tip of each part there are m digits (33a), (3
3b) Wgb matching arm (c), to the proximal side of (to),
Both are provided with an actuating part (a) for applying an external force, and based on the movement of the piston (38a), the arm...
By driving each of the two sets of claw portions 6e in the approaching and separating directions,
The IC on the table can be positioned simultaneously from four directions.

Next, the operation of the positioning device configured as described above will be explained.

First, the flat packaged IC shown in FIG. 832 (4) is placed on the table Q with each arm (B) open. Next, a suction device (not shown) is activated to attract the IC onto the table Q.

As a result, the IC is positioned and fixed horizontally to the table 6. It goes without saying that the IC is movable in the horizontal direction. After this, hydraulic cylinder 0!
3 in the direction in which the piston (38a) retreats,
Using each fixing pin (34a) as a fulcrum, each of the 2 m long claws G gradually moves synchronously in the closing direction. Then, at the point where each of the two sets of claws Oe... makes contact with each pin arranged in the four directions of the IC, the IC that was previously set in the X direction, the IC that was set with a misalignment in the X direction, and the An IC set with a positional shift in the circumferential direction is corrected by a minute movement in the horizontal direction due to the pressing of the claws C. Then, when the position adjustment by these two sets of claws C8... is completed, ICf is reached by the two sets of claws Ω0...

When the final state of restraining from four directions is reached, the IC will be positioned with high precision in the desired state necessary for mounting on a substrate (not shown).

By sniffing, it is possible to easily and accurately position an IC, which is difficult to do.

In the above embodiment, an IC having pins in four directions is used as an electronic component, but the same applies to an IC having pins in two directions.

It goes without saying that the present invention can be applied not only to ICs but also to electronic components such as other semiconductor devices.

Further, specific embodiments of the first and second heating heads αT)aa will be described with reference to FIGS. 4 and 5.

In the figure, 61), 1◇ is a chip stand on which two heater tips are attached (separately attached to each), and this chip stand G11), 81) is built into the holder device (13).

Each of the chip stands (6) @°C is fastened to a pair of left and right heat sinks 6→, four-sided, and with a screw k with all electrical insulating material interposed therebetween.

Each of the heat sinks aψ, (g) is made of a metal material as a conductor. Furthermore, each heat sink (
), (one lower end each has a conductive support arm 4)
1E), @9 is provided protrudingly, and this support arm is cut.

A plate-shaped heater chip) is installed between the two.

This heater chip (one is made of tandusten (W), molybdenum (Mo)t or stainless steel (SUS))
It is designed to generate heat when energized by an energizing circuit, which will be described later. The heater tips (6) are still supported in parallel with their plate surfaces facing each other. In addition, each step stand 6p, (6
) are supported by the rail stand 6a of the holder assembly &13, and guided and moved in the same horizontal direction.

It is operated by a feed screw Q provided on the side of the tab and rail base 6, and is fixed at its adjusted position by set screws 6 and 9. In this way, by adjusting the movement of the chip stand @υ and the kick, the gaps and positions of the six opposing heater chips (6) can be selected.

Further, each of the above-mentioned rail stands Q, 63 is provided with a support arm (to) protruding from each other, and each of the support arms (2) is provided with a protruding support arm.

(To) extends upward through the frame (A) of the holder device (G). And each support arm 6G, 5
5 is adapted to be inserted into the system only in the vertical direction without rotating due to a bearing (not shown) formed within the frame can. (on the frame) has a support rod G'θ.

G? ) is fixedly attached, and a seesaw plate (to) is pivotally supported at the upper end of the support rod 6゛θ, 67). A retaining groove G9 is formed at each end of the seesaw plate (to), and these engaging grooves (for 416LJ, there are grooves 6 provided at each tip of the support arm (to) and CfI). ), (
3υ are fitted and engaged. Thus, the support arms (to) and Q are alternately raised and lowered in opposite directions via the scene board (to). In addition, 6 in Figure 5
. . . is the support arm (toward) and the steady grate of 69.

The moving operation holder device (transformer) constructed in this way is driven up and down by a small lift device (not shown) via a connecting rod protruding from its 71/-m (10). .

On the other hand, power is supplied to each of the heater chips (6) and the power supplies shown in FIG. ), each heat sink 6→, 6, and support arm u! from the power supply terminal 6L provided on each corresponding rail stand 6a, aa, respectively. 8
．． It is possible to supply electricity to the heater tip) and (6) through f19. In addition, this energization operation is performed by the control unit (
7), the heater chips (6) and (6) are connected to the lead pins (9) (11) of the flat package WIC (4).
, is performed when pressing α0(6).

Furthermore, the temperature of the heater chips @a, (6) can be detected by thermocouples (b), 671 as temperature detection sensors, and this signal is sent to the control unit (a). The strength of the current sent to θ is controlled.

By the way, the flat package IC (4) as an electrical component to be soldered has a large number of lead pins (9) αOαυG protruding from each of the four sides of the rectangular package (4) as shown in Fig. 4. Each of the lead pins is soldered to an electrode butt (not shown) as a connected portion of the circuit board (1).

That is, the heat sink 0→ by the feed surrounding screw C).

so as to be able to correspond to the lead pins on opposite sides of each. Then, the lifting drive device is activated to lower the holder device (roller) and push each heater chip onto the flat package type I8 ball lead pins previously installed on the circuit board (1).

Even if offset occurs at this time, each heater chip θa, aa is supported in an independent suspension manner by the see-saw plate (to) as described above, so each heater chip θa, aa is pressed against the lead pin with a uniform load, for example, 2~ Pressurize with 5 Kq. At the same time, the heater chips (6) and (6) are energized to heat them, and the temperature is detected by a thermocouple 67), which is fed back to the control unit (a) and the necessary current is supplied to the power source. (to) and heated at a predetermined temperature.

In addition, each temperature control is performed by each heater chip II,
3. This is done every GI2.

Soldering is performed while pressing and heating in this manner.

[Effect of J emitted]

As explained above, according to the present invention, there is an effect that the mounting of a fixed package type semiconductor device can be automatically performed with constant mounting.

In the above embodiment, an IC was explained, but the same effect can be obtained by applying the same to a transistor.

Furthermore, in the above embodiment, an example was explained in which the IC was positioned and then transported to a predetermined position on the circuit board, but the transport means (7) was equipped with a TV left camera for recognizing congratulatory messages, and the position was recognized by visual recognition. It's okay.

[Brief explanation of drawings]

Figure 1 is a diagram for explaining the embodiment of the method of the present invention No. 41, Figure 2 is a diagram for explaining Figure 1, and the figure is a plan view of a flat package IC. FIG. 3 is a front view of the device for explaining a specific example of the positioning section shown in FIG. 1, and FIGS. In the figures, FIG. 4 is a kitchen view, and FIG. 5 is a side view. In the figure, 1...Circuit board 3...Table 6...Positioning part 7...Transporting means 17.19...Heating head representative Patent attorney Noriyuki Chika (and 1 other person) Figure 2 ( B) Figure 3 Hayabusa Figure 4 Figure 5

Claims (2)

[Claims] (1) A step of transporting printed circuit boards one by one on which a lead pattern of a semiconductor element and a printed circuit are formed and an insulating film is provided on the surface of the circuit, and the above-mentioned leads of the printed circuit board transported in this step are carried out in advance. A process of attaching solder flux onto the solder layer laminated on the pattern, and a flat package type semiconductor device in which the lead pins of the flat package type semiconductor element are placed on the lead pattern to which the flux is attached through this process. a step of installing a semiconductor element, and means for melting and soldering the solder layer by simultaneously heating a lead pin row on at least one side of the flat package type semiconductor element installed in the step with a heater chip in a pressed state; 1. A method for automatically mounting a flat package type semiconductor element, comprising the steps of separating the heater chip after soldering by the means and transporting the printed circuit board on which the flat package is mounted. (2) The method for automatically mounting a flat package semiconductor device according to claim 1, wherein the flat package semiconductor device has lead pin rows on at least two sides.