JP2002340962A - Method and device for inspecting printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for inspecting printed wiring boards capable of realizing space saving and a low cost and superior in productivity. SOLUTION: The inspection method inspects the printed wiring board 1 erecting electronic parts and a plurality of pins on a substrate having a circuit. A carrying-in process for carrying the printed wiring boards 1 to be inspected in a substrate jig 201 on a rotary table 20, an electric inspection process for performing continuity inspection of the printed wiring boards 1 and capacity inspection of the electronic parts, a visual examination process for performing visual examination of the pins, and a separation process for discharging the printed wiring boards 1 which are judged defective in the electric inspection process or the visual examination process and carrying out the printed wiring boards 1 which are judged nondefective to a next process are performed on each stage. The printed wiring boards 1 are successively transferred to each stage by the rotary table 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrical inspection of a printed wiring board, a method for inspecting the appearance of a plurality of conductive connection terminals erected on the printed wiring board, and an inspection apparatus used for the method.

[0002]

2. Description of the Related Art Conventionally, there is known a printed wiring board 9 for mounting electronic components as shown in FIG. The surface circuit 931 of the printed wiring board 9 conducts with the corresponding internal circuit 93 inside the printed wiring board 9, and the internal circuit 932
Are configured to be electrically connected to the corresponding back surface terminals 933 on the back surface of the printed wiring board 9 as shown in FIG.
The surface circuit 931 and the back terminal 933 are formed of solder bumps. When mounting an electronic component 8 such as a flip chip on the printed wiring board 9, in order to make the electronic component 8 and the internal circuit 932 of the printed wiring board 9 conductive,
Surface circuit 931 and solder bump 8 formed on electronic component 8
1 are connected in a flip-chip manner.

[0006] As shown in FIG. 16, the printed wiring board 9 has a plurality of pins 912 erected on rear terminals 933 of a substrate 91. The pin 912 is a conductive connection terminal, and uses a pin-shaped lead wire. As a result, the output from the electronic component 8 is transferred to the solder bump 9
10, through the internal circuit 932, it can be pulled out to the back side of the printed wiring board 9 or an input from the back side can be transmitted to the electronic component 8. In FIG. 15, the pins 912 are omitted.

With respect to the printed wiring board 9 described above, a continuity test of the pins 912, a capacity test of mounted capacitors and the like, and an appearance test of the pins 912 are performed. The appearance inspection is performed on the printed wiring board 9.
For example, a pin 91 having a bent pin as shown in FIG.
This refers to inspection for the presence or absence of 2a. The continuity inspection, the capacitance inspection, and the appearance inspection are performed using a continuity inspection machine, a capacitance inspection machine, and an appearance inspection machine, respectively.

[0005]

However, the above inspections are individually performed by the continuity inspection machine, the capacitance inspection machine, and the appearance inspection machine. That is, the printed wiring board to be inspected needs to be repeatedly carried in and out of the continuity inspection machine, the capacity inspection machine, and the appearance inspection machine.
Therefore, it is difficult to improve the inspection efficiency, and it is difficult to secure sufficient productivity. In addition, installing each inspection machine individually increases the installation space. Further, there is a problem that ancillary equipment such as a transporter that needs to be provided between the inspection machines increases, and as a result, the inspection cost increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to provide a method and an apparatus for inspecting a printed wiring board which realizes space saving, low cost, and is excellent in productivity. It is.

[0007]

According to a first aspect of the present invention, there is provided a method of inspecting a printed wiring board on which electronic components and a plurality of conductive connection terminals are erected on a substrate having a circuit, the method comprising: A carrying-in step of carrying in a substrate jig set on a transfer means, an electric inspection step of conducting a continuity inspection of the printed wiring board and a capacitance inspection of the electronic component, and an appearance inspection step of carrying out an appearance inspection of the conductive connection terminals And a separating step of discharging the printed wiring board determined to be defective in the electrical inspection step or the appearance inspection step from the transfer means and carrying out the printed wiring board determined to be non-defective from the transfer means to the next step. Wherein the printed wiring board is transferred to each of the stages by the transfer means. In the inspection method for one-plate (claim 1).

In the present invention, after the printed wiring board is carried into the transfer means, a continuity test, a capacity test, and an appearance test are performed, and then the printed wiring board is carried out or discharged. Therefore, it is not necessary to repeat loading and unloading of the printed wiring board in each of the continuity inspection step, the capacitance inspection step, and the appearance inspection step. Therefore, the inspection efficiency is improved, and a method for inspecting a printed wiring board excellent in productivity can be obtained. Further, since it is not necessary to provide many transporters and other auxiliary equipment between each inspection process, it is possible to realize space saving and cost reduction in the inspection process.

As described above, according to the present invention, it is possible to provide a method for inspecting a printed wiring board which realizes space saving, low cost, and is excellent in productivity.

According to a second aspect of the present invention, there is provided an inspection apparatus for inspecting a printed wiring board having electronic components and a plurality of conductive connection terminals erected on a substrate having a circuit. A continuity inspection machine for inspecting the continuity of the electronic component, a capacitance inspection machine for inspecting the capacitance of the electronic component, an appearance inspection machine for inspecting the appearance of the conductive connection terminal, and a transfer means for holding and transferring the printed wiring board. Wherein the continuity inspection machine, the capacitance inspection machine, and the appearance inspection machine are provided on respective stages arranged along the transfer means, and the transfer means mounts the printed wiring board on each of the stages. A printed wiring board inspection apparatus is configured to be transferred to a stage (Claim 4).

In the inspection apparatus according to the present invention, the continuity inspection machine, the capacitance inspection machine, and the appearance inspection machine are provided on each stage arranged along the transfer means. Therefore, the printed wiring board held by the transfer means is sequentially transferred to each of the stages. That is, it is not necessary to repeat the loading and unloading of the printed wiring board to each of the continuity inspection machine, the capacity inspection machine, and the appearance inspection machine. Therefore, inspection efficiency is improved and productivity is improved. Further, since there is no need to provide many transporters and other ancillary equipment between the inspection machines, space and cost reduction in the inspection process can be realized.

As described above, according to the present invention, it is possible to provide an inspection apparatus for a printed wiring board which realizes space saving, low cost, and is excellent in productivity.

[0013]

In the first invention (claim 1), the continuity test refers to, for example, a test for the presence or absence of a disconnection or a short circuit of the conductive connection terminal or a circuit on a substrate.
Further, the above-mentioned electronic component refers to, for example, a capacitor or the like. The capacitance test is, for example, a test for determining whether or not the capacitance of the capacitor is appropriate. Further, in the above-described electrical inspection step, for example, electrical characteristics such as resistance and inductance mounted on the printed wiring board can be inspected.

The appearance inspection refers to, for example, an inspection for the presence or absence of a pin defect such as a bent or floating pin of the conductive connection terminal. The term "pin bending" means that the pins are set upright with respect to the substrate and that the pins themselves are bent. Also, the above pin lift is
It means that the pins erected on the substrate protrude beyond a specified value. For example, this is a problem that occurs when the pin is incompletely contacted with a solder bump in a solder pad formed on the substrate. In the appearance inspection, for example, the inspection of the pin bending and the inspection of the pin floating may be performed in the same step, or may be performed in different steps. The same applies to the following definitions.

Further, any of the above-described electrical inspection step and appearance inspection step may be performed first, and the order does not matter. Further, the sorting step may be performed separately after the electrical inspection step and the appearance inspection step, or may be performed collectively after both steps are completed.

It is preferable that the transfer means is a rotary table. In this case, further space saving and lower cost can be realized, and productivity can be further improved.

In the electric inspection step and the appearance inspection step, a plurality of the printed wiring boards are inspected in a set, and only a part of them is determined to be good in the electric inspection step and the appearance inspection step. In the above-mentioned separation process, the above-mentioned non-defective printed wiring board is temporarily placed on a temporary placing stage, and only a part of a set of a plurality of printed wiring boards to be inspected thereafter is non-defective. In addition, it is preferable that the non-defective printed wiring board and the printed wiring board temporarily placed on the temporary placement stage be brought out together (claim 3). In this case, even when a defective product occurs, a plurality of non-defective products can be carried out to the next process in a set, so that the productivity can be further improved.

For example, in the case of inspecting two printed wiring boards in pairs, if only one of them is determined to be non-defective, the non-defective printed wiring board is temporarily placed on the temporary placement stage. Also, for example, in the case of inspecting a set of three of the above printed wiring boards, if only one or two of them are determined to be non-defective, the one or two non-defective printed wiring boards are replaced with the above-described one. Place temporarily on the temporary placement stage.

Next, in the second invention (claim 4), the number of the continuity inspection machine, the capacity inspection machine, and the appearance inspection machine may be one or plural. Preferably, the transfer means is a rotary table. In this case, further space saving and lower cost can be realized, and productivity can be further improved.

The inspection apparatus has a temporary placement stage for temporarily placing a non-defective printed wiring board. The continuity inspection machine, the capacity inspection machine, and the appearance inspection machine include a plurality of the printed wiring boards. Inspection by a pair, if only a part of them is judged to be good by each inspection machine,
The non-defective printed wiring board is temporarily placed on the temporary placement stage, and if only a part of a plurality of sets of printed wiring boards to be inspected thereafter is non-defective, the non-defective printed wiring board is It is preferable that the printed wiring board temporarily placed on the temporary placement stage be taken out together with the printed wiring board (claim 6). In this case, even when a defective product occurs, a plurality of non-defective products can be carried out to the next process in a set, so that the productivity can be further improved.

[0021]

(Embodiment 1) FIGS. 1 to 11 show a method and an apparatus for inspecting a printed wiring board according to an embodiment of the present invention.
This will be described with reference to FIG. As shown in FIG. 3, the method for inspecting a printed wiring board according to the present embodiment is a method for inspecting a printed wiring board 1 having an electronic component 16 and a plurality of conductive connection terminals 12 erected on a substrate 11 having a circuit. . As the conductive connection terminal 12, a terminal using a pin-shaped lead wire (hereinafter, simply referred to as "pin 12") is used. In addition, a capacitor is used as the electronic component 16 (hereinafter, referred to as “capacitor 16”).

In the above inspection method, the following loading step, electrical inspection step, appearance inspection step, and sorting step are performed at each stage (FIG. 1). That is, in the carrying-in step, the printed wiring board 1 to be inspected is carried into the substrate jig 201 set on the rotary table 20 as a transfer means. In the electrical inspection step, the continuity inspection of the printed wiring board 1 and the capacitor 16
(FIGS. 6 and 7).

In the visual inspection step, the pins 1
2 is carried out (FIGS. 8 to 11). In the sorting step, the printed wiring board 1 determined to be defective in the electrical inspection step or the appearance inspection step is discharged from the rotary table 20, and the printed wiring board 1 determined to be non-defective is removed from the rotary table 20. To the next process. And, by the above-mentioned rotary table 20,
The printed wiring board 1 is sequentially transferred to each of the stages.

As described above, the electrical inspection step includes a continuity inspection step and a capacitance inspection step. The above-mentioned stages are the carry-in stage 21 and the continuity inspection stage 2
2, five stages of a capacity inspection stage 23, a visual inspection stage 24, and a carry-out stage 25. In addition, the continuity test refers to a test for the presence or absence of a disconnection or short circuit of the circuit on the pin 12 or the substrate 11. In addition, the capacitance inspection refers to an inspection of whether or not the capacitance of the capacitor 16 is appropriate.

The appearance inspection refers to, for example, an inspection for the presence or absence of a pin defect such as a bent or floating pin. The term "pin bend" means that the pins 12 are set up obliquely with respect to the substrate 11 (see reference numeral 12a in FIG. 9A), and that the pins 12 themselves are bent.
Also, the term “pin lifting” means that the pins 12 erected on the substrate 11 project beyond a specified value (FIG. 11).
(See reference numeral 12b in (A)). For example, this is a problem that occurs when the pins 12 abut incompletely on the solder bumps in the solder pads formed on the substrate 11. In the above-described appearance inspection, the inspection of the pin bending and the inspection of the pin floating are performed in the same process.

Next, an inspection apparatus 2 for inspecting the printed wiring board 1 will be described with reference to FIG. The inspection apparatus 2 includes a continuity inspection machine 32 for inspecting the continuity of the printed wiring board 1, a capacitance inspection machine 33 for inspecting the capacitance of the capacitor 16, an appearance inspection machine 34 for inspecting the appearance of the pins 12, A rotary table 20 for holding and transferring the printed wiring board 1;

The continuity inspection machine 32, the capacity inspection machine 33, and the appearance inspection machine 34 are provided on respective stages arranged along the rotary table 20. That is, the continuity inspection machine 32 is disposed on the continuity inspection stage 22, the capacitance inspection machine 33 is disposed on the capacitance inspection stage 23, and the appearance inspection machine 34 is disposed on the appearance inspection stage 24. Then, the turntable 20 sequentially transfers the printed wiring board 1 to each of the stages. A carry-in machine 31 is arranged on the carry-in stage 21 and a carry-out machine 35 is arranged on the carry-out stage. Further, a substrate jig 2 for mounting the printed wiring board 1 to be inspected so as to correspond to each stage.
Reference numerals 01 to 205 are provided on the turntable 20.

Hereinafter, a method for inspecting the printed wiring board 1 of the present embodiment will be described in detail. As shown in FIG.
The inspection device 2 of this example has a circular rotary table 20,
It comprises a drive system (not shown) for rotating and driving the rotary table 20 and a control system (not shown). The stages are arranged annularly at regular intervals along the outer circumference of the turntable 20. In each of these stages, each process (each process) required for inspection of the printed wiring board 1 is performed on each printed wiring board 1 in parallel in time.

Further, five substrate jigs 201 to 205 corresponding to the respective stages in a one-to-one correspondence are arranged on the rotary table 20 at equal intervals. Each of the board jigs 201 to 205 has two mounting portions (not shown), and can mount two printed wiring boards 1 at the same time. Although not shown, the substrate jig 2
01 to 205, the printed wiring board 1 is
It has a clamp for fixing to ~ 205.

Hereinafter, the operation of the inspection apparatus 2 of the present embodiment will be described. As shown in FIG. 2, first, a pallet 5 on which a plurality of (eight in this example) printed wiring boards 1 are mounted.
Is fed from a charging machine 40 and is conveyed to a carry-in position 41 by a conveyor 4 for conveyance. The printed wiring board 1 on the pallet 5 transported to the loading position 41 is
Is transferred onto the substrate jig 201 installed on the rotary table 20 in the loading stage 21.

The printed wiring board 1 placed on the substrate jig 201 repeats the rotational movement of the turntable 20 in the direction of arrow A in FIGS. 1 and 2 at a constant angle (72 ° in this example). Then, an inspection is performed in each of the continuity inspection stage 22, the capacitance inspection stage 23, and the appearance inspection stage 24, and it is determined whether or not the printed wiring board 1 is non-defective.

The discriminated printed wiring board 1 which is regarded as a non-defective product is set on the non-defective conveyer 4 by the unloader 35 when it reaches the unloading stage 25 by the rotation of the rotary table 20. Is transferred to the pallet 5. When the non-defective printed wiring board 1 is placed on all of the mounting portions 51 of the pallet 5, the pallet 5 is moved on the conveyor 4 toward the receiver 49. Then, the printed wiring board 1 on the pallet 5 carried into the receiver 49 is
By the transfer device, it is stored in two units in the shipping tray,
When the tray runs out of space, the tray is transferred to an actual shipping tray unloading section (not shown).

The printed wiring board 1 determined to be defective as a result of the inspection process at each stage is:
The unloader 35 sorts out the defective items on the pallet 5 placed on the defective product unloading conveyor 44 and discharges them. That is, the defective product carrying conveyor 44 comprises a conduction defective conveyor 442, a capacity defective conveyor 443, and an appearance defective conveyor 444. Then, the printed wiring board 1 determined to be defective in the continuity inspection step is transferred to the continuity defective conveyor 442, and the printed wiring board 1 determined to be defective in the capacity inspection step is transferred to the defective capacity conveyor 443 to the appearance inspection step. The defective printed wiring board 1 is discharged to the appearance defect conveyor 444, respectively.

As shown in FIGS. 1 and 2, a temporary placement stage 26 for temporarily placing non-defective products is
Is installed. As shown in FIGS. 4A to 4D,
The pallet 5 is provided with a mounting part 51 so that the printed wiring board 1 can be processed two by two by the unloader 35. That is, the unloading machine 35 combines the two printed wiring boards 1 unloaded from the unloading stage 25 into two mounting units 511 and 51 arranged in the short direction of the pallet 5.
2 can be mounted at once.

However, in each inspection stage, the printed wiring boards 1 are inspected in units of two, and for example, only one of them may be transferred to the carry-out stage 25 as a non-defective product. In this case, the unloader 35 transfers the printed wiring board 1
As shown in (A), the pair of mounting portions 511, 512
Will be mounted on only one of them. Then, the printed wiring board 1 to be carried out next is mounted on both or one of the other pair of mounting portions 511 and 512 of the pallet 5 (FIGS. 5A to 5D). Then, as shown in FIG. 5D, the pallet 5 has a mounting portion 51 on which the printed wiring board 1 is not mounted.
Since the data is sent to the receiver 49, the productivity is reduced.

Therefore, when the unloader 35 cannot process two printed wiring boards 1 at the same time, the one good printed wiring board 1 is placed on the temporary placement stage as shown in FIGS. 26 temporarily. Then, when only one non-defective product is transferred to the unloading stage 25 later, two of the non-defective products together with the printed wiring board 1 stocked on the temporary placing stage 26 are simultaneously transferred to the conveyor 4.
It is carried out to the upper pallet 5.

If the temporary placement stage 26 is provided as described above, even if only one printed wiring board 1 having undergone the inspection process is transferred to the unloading stage as a non-defective product, the printed wiring board 1 is mounted as described above. There is no need to carry out the pallet 5 in a state where there is no mounting portion 51 (FIG. 5D).

In this embodiment, the printed wiring board 1
In the above, an example in which a pair is inspected as a set is shown, but the present invention is not limited to this, and an inspection can be performed in a set of three or more. In this case, the configuration of the unloader 35, the pallet 5, the temporary placement stage 26, and the like, or the processing method of the printed wiring board 1 and the like are determined by the inspection method (the method of inspecting the printed wiring board with a set of three or more). As appropriate.

Each stage will be described below. As shown in FIG. 1, the carry-in stage 21 is provided with a carry-in machine 31, and the carry-in machine 31 causes the uninspected printing on the substrate jig 201 provided on the rotary table 20 in the inspection device 2 from the conveyor 4. The wiring board 1 is carried in (a carrying-in step).

The printed wiring board 1 is placed on the substrate jig 201.
Is placed on the rotary table 20, the arrow A in FIG.
Then, the substrate jig 201 on which the printed wiring board 1 is mounted is moved to the continuity inspection stage 22.

In the continuity inspection stage 22, the continuity inspection step of the printed wiring board 1 is performed as follows. Figure 1
As shown in FIGS. 6 and 7, the continuity inspection stage 22 includes:
A continuity inspection machine 32 is provided. The continuity inspection machine 32
As shown in FIG. 6, the probe pins 3 are configured so as to be able to correspond one-to-one with the pins 12 on the printed wiring board 1.
A checker head 322 provided with a probe 23 and a lead wire 326 configured to be able to correspond to the probe pin 323 one-to-one.
And apply a certain pressure to the upper surface side of the printed wiring board 1,
A pressing jig 325 is provided.

The probe pin 323 has elasticity, and sinks downward in FIG.
The pin 12 is connected to the wire 3 connected to the probe pin 323.
26 (see FIG. 7).

The continuity tester 32 has the following sending unit and detecting unit (not shown). The sending section supplies a signal, a current, a voltage, and the like necessary for conducting a continuity test, such as a current, to the probe pin 323. The detection unit detects whether the checker head 322 is conductive to the pin 12 via the probe pin 323, and detects a conductive signal or a non-conductive signal.

Hereinafter, a method of inspecting the continuity of the pins 12 erected on the printed wiring board 1 using the continuity inspection machine 32 will be described.
This will be described with reference to FIGS. 6 and 7
1, the capacitor 16 is omitted. When the substrate jig 202 moves to the continuity inspection stage 22, as shown in FIG. 6, the pins 12 erected on the substrate 11 and the probe pins 323 of the checker head 322 are surely integrated into one. The printed wiring board 1 is supported by a substrate jig 202 in a state where the printed wiring board 1 is positioned so as to be in contact with the printed wiring board 1.

In this state, the checker head 322
Is raised from below in the direction of arrow F shown in FIG.
08 on the lower surface 14 of the printed wiring board 1 placed on the substrate jig 202 having the checker head 322.
Of the printed wiring board 1 while the probe pins 323 are in contact with the corresponding pins 12, respectively.
Float from. Next, a certain pressure is applied to the upper surface 13 of the printed wiring board 1 by lowering the pressing jig 325 as shown by the arrow G (FIG. 7).

As described above, the probe pin 323
Has a resiliency, so that it sinks downward by contact with the pin 12 and contacts the conductive wire 326. Since the pins 12 are configured to conduct between specific pins via the conductor circuit 113 of the printed wiring board 1, by passing electricity to the specific pins, the pins are normally connected if they are normally conducted. Is detected.

Therefore, when the pin 12 to be turned on is not turned on, the defect (OP
EN failure) is detected, and if pins that should not be conductive are conductive, extra pins 12 are attached during the manufacturing process, or solder bumps connecting the pins 12 are not connected. It is detected that the connection is defective (SHORT failure). By performing the above inspection for all the pins, the continuity inspection of the pins 12 erected on the printed wiring board 1 is completed.

Next, the rotary table 20 is rotated by 72 ° in the direction of arrow A in FIG. 1, and the printed wiring board 1 having undergone the continuity inspection step is transferred to the capacitance inspection stage 23. In the capacitance inspection stage 23, a capacitance inspection step is performed as follows. The basic structure of the capacitance inspection device 33 is the same as that of the above-described continuity inspection device 32, and thus the description thereof is omitted.
Capacitor 16 mounted on printed wiring board 1 (FIG. 3)
Are wired so as to correspond to the pair of pins 12, the capacitance is inspected by applying a voltage to the pins 12. The following is an example of a capacity test.

Twelve capacitors 16 are mounted on the printed wiring board 1 of this embodiment.
It is divided and connected to 8 nets.
In this example, a capacitor having a capacitance of 1.00 μF per capacitor is used. The above capacitor 16
A capacitor which exhibits a capacity of 80% to 120% of the electric capacity of the capacitor 16 when an AC voltage of 1 V and 100 Hz is applied thereto is regarded as a non-defective product. That is, the four nets are 3.2 to 4.8 μF, and the eight nets are 6.4 to 6.4 μF.
If it is in the range of 9.6 μF, it is determined to be good.

Next, the rotary table 20 is rotated by 72 ° in the direction of arrow A in FIG. 1, and the printed wiring board 1 after the above-described capacitance inspection step is moved to the appearance inspection stage 24. In the appearance inspection stage 24, an appearance inspection step is performed as follows.

First, in the appearance inspection stage 24, an appearance inspection machine 34 for the pins 12 erected on the printed wiring board 1.
This will be described with reference to FIGS. As shown in FIG. 8B, the visual inspection machine 34 includes an inspection jig 340 having the plurality of pin holes 342 and the laser beam 34.
1 for transmitting the laser beam. The printed wiring board 1 is placed on the inspection jig 340 from above with the pins 12 inserted into the pin holes 342.

The transmission type laser sensor 346 is shown in FIG.
(B), as shown in FIG.
41 detects that the printed wiring board 1 has been interrupted, and detects that the printed wiring board 1 is bent according to the detection signal. In the opening of the pin hole 342, a taper portion 345 for adjusting a minute displacement between the printed wiring board 1 and the inspection jig 340 when the pin 12 is inserted into the pin hole 342 is provided. is there.

The transmission type laser sensor 346 is shown in FIG.
(B), as shown in FIG. 10, a pair of a projecting body 347 that emits the laser light 341 and a light receiving body 348 that receives the laser light 341.

As shown in FIG. 10, two laser beams 341 travel along two diagonal lines of the substrate 11. As means for this, as shown in FIG. 10, two pairs of the transmission type laser sensors 346 are arranged on an extension of two diagonal lines of the substrate 11. That is, outside the adjacent two corners 111 of the rectangular substrate 11,
One projecting body 347 is arranged, and one light receiving body 348 is arranged with respect to each projecting body 347 outside two corners 112 that are diagonal of the substrate 11.

8 (A), 9 (A) and 11
As shown in (A), the pin hole 342 of the inspection jig 340 has a bottom 344. And FIG.
(B), as shown in FIG. 11B, the tip 121 of the pin 12 is brought into contact with the bottom 344. At this time, FIG.
As shown in FIG. 1B, it is detected that at least one of pin bending and pin lifting of the printed wiring board 1 has occurred due to the laser light 341 being blocked by the printed wiring board 1.

The pin lifting means that the pins 12 erected on the substrate 11 protrude from the substrate 11 beyond a specified value, as shown in FIG. FIG. 11 (A)
In, the second pin 12b from the right is in a pin floating state. For example, this is a problem that occurs when the pins 12 abut incompletely on solder bumps (not shown) in the solder pads formed on the substrate 11. The specified value has, for example, a 1.1 L relationship with the protruding length L of the normally erected pin. Further, the depth D of the pin hole 342 has a relationship of D = L ± 0.1 mm with respect to the protruding length L of the normally erected pin. It is more preferable that D = L.

Next, the procedure of the method for inspecting a printed wiring board according to this embodiment will be described with reference to FIGS. 8 to 11, the capacitor 16 is omitted. In addition, the inspection jig 3 corresponds to the capacitor 16.
The counterbore 40 is provided with a counterbore (not shown).

First, as shown in FIG. 8A, the printed wiring board 1 has a substrate jig 204 having an opening 209.
The pin 12 is supported so that the pin 12 faces downward. The inspection jig 340 is arranged below the substrate jig. From this state, the arrow C in FIG.
As shown in (2), the inspection jig 340 is moved upward. As a result, as shown in FIG. 8B, the printed wiring board 1 is placed on the upper surface 343 of the inspection jig 340. At this time, the pin 12 is inserted into the pin hole 342.

In this state, the transmission type laser sensor 3
46, the printed wiring board 1 is connected to the inspection jig 34.
From 0, it is determined whether it is floating above the specified value (M-N) or not. That is, as shown in FIG. 8B, if the printed wiring board 1 is not floating above the specified value (M−N), the laser beam 341 emitted from the projection body 347 in the transmission type laser sensor 346 becomes
The light reaches the photoreceptor 348 without being blocked by the printed wiring board 1. At this time, the printed wiring board 1 is determined to be non-defective.

On the other hand, as shown in FIGS. 9B and 11B, if the printed wiring board 1 is floating above the specified value (MN), the laser light emitted from the projecting body 347 341 is blocked by the printed wiring board 1 and does not reach the photoreceptor 348. At this time, the printed wiring board 1 is determined to be defective.

As described above, the transmission type laser sensor 3
46 is the upper surface 13 of the printed wiring board 1 and the inspection jig 3
When it is detected that the pin is above a predetermined distance M from the upper surface 33 of the pin 40, it is detected that the pin is bent or the pin is lifted. In other words, when neither pin bending nor pin lifting occurs, the pin 12 is completely inserted into the pin hole 342 of the inspection jig 340 as shown in FIG. 8B.

However, when the pin is bent as shown in FIG. 9A, the pin 12a comes into contact with the side wall of the pin hole 342 as shown in FIG. 9B. Therefore, the pin 12 is not completely inserted into the pin hole 342. As a result, the substrate 11 is
Floating from.

In the case where a pin is lifted as shown in FIG. 11A, the pin 12b having a large protrusion comes into contact with the bottom 344 of the pin hole 342 as shown in FIG. . Therefore, the pin 12 is not completely inserted into the pin hole 342. As a result, the substrate 11 floats from the inspection jig 340.

Therefore, the upper surface 13 of the printed wiring board
Is above a predetermined distance M from the upper surface 33 of the inspection jig 340, it means that at least one of pin bending and pin lifting has occurred.

The board jig 20 on which the printed wiring board 1 has been subjected to the continuity inspection step, the capacitance inspection step, and the appearance inspection step
5 is that the rotary table 20 is rotated by 72 °,
It moves to the unloading stage 25. As shown in FIG. 2, the printed wiring board 1 of the unloading stage 25 is palletized by the unloader 35 on the conveyer 4 for unloading non-defective products.
Transported up. When the non-defective printed wiring board 1 is placed on the entire mounting portion 51 (FIG. 4D)
Moves on the conveyor 4 toward the receiver 49.

On the other hand, as for the printed wiring board 1 which is determined to be defective as a result of the inspection process, the unloading stage 25
Is classified by the unloader 35 for each defective item.
It is stored and carried out on a pallet 5 placed on a conveyor 44 for discharging defective products.

Thereafter, by repeating the above steps, a large number of printed wiring boards 1 to be sequentially inspected are obtained.
The continuity inspection, the capacitance inspection, and the appearance inspection are sequentially performed.
Further, the loading step, the sorting step, and each inspection step are performed in parallel in time.

Next, the operation and effect of this embodiment will be described. In this embodiment, after the printed wiring board 1 is carried into the rotary table 20, a continuity inspection, a capacity inspection, and an appearance inspection are performed, and then the printed wiring board 1 is carried out or discharged.
Therefore, there is no need to repeatedly carry in and carry out the printed wiring board 1 in each of the continuity inspection step, the capacitance inspection step, and the appearance inspection step. Therefore, the inspection efficiency is improved, and a method for inspecting a printed wiring board excellent in productivity can be obtained.
Further, since it is not necessary to provide many transporters and other auxiliary equipment between each inspection process, it is possible to realize space saving and cost reduction in the inspection process.

Further, since the means for transferring the printed wiring board 1 is the rotary table 20, further space saving, lower cost can be realized, and productivity can be further improved.
In addition, since the inspection device 2 has the temporary placing stage 26, as described above, even if a defective product occurs, a plurality of non-defective printed wiring boards 1 (two in this example, one set) ) Can be carried out to the next process, so that the productivity can be further improved.

As described above, according to the present embodiment, it is possible to provide a method and an apparatus for inspecting a printed wiring board which achieves space saving, low cost, and excellent productivity.

(Embodiment 2) This embodiment is a specific example of a printed wiring board to be inspected by the inspection method of the present invention, as shown in FIGS. As shown in FIG. 12, the printed wiring board 1 is formed by sequentially forming a conductive circuit 113 and an interlayer resin insulating layer 143 on a substrate 11.
A solder resist layer 136 for protecting the internal circuit 113 is formed on a surface layer of an upper surface (chip mounting surface) 13 and a lower surface (connection surface with a daughter board and a mother board) 14 of the substrate 11 constituting the printed wiring board 1. Have been.
Openings 1 are provided at a plurality of positions on the solder resist layer 136.
5 are formed. A conductor circuit 113 is provided in the opening 15.
Are partially arranged, and solder pads 13 for forming solder bumps are provided.
7 are formed.

The openings 15 are formed on both the upper surface 13 and the lower surface 14 of the printed wiring board 1. On the upper surface 13 of the printed wiring board 1, a solder bump 110 for connecting an IC chip is formed on the opening 15 described above. On the other hand, on the lower surface 14 side of the printed wiring board 1, conductive connection pins 12 are connected to the openings 15 via solder bumps 110 serving as a conductive adhesive. The pin 12
Are connected to the substrate 11 from a state in which a plurality of pins are erected on a dedicated pin alignment jig.

As a method of forming the opening 15 by opening the solder resist layer 136, for example,
A method using a carbon dioxide (CO ₂ ) laser, an ultraviolet laser, and an excimer laser can be used. When the above-mentioned excimer laser is used, it is desirable to use a hologram laser. Using this type of laser,
By irradiating a laser beam through a mask, a large number of openings 1 are formed in the solder resist layer 136 by one irradiation.
5 can be formed efficiently. The hologram method is a method of irradiating a target object with a laser beam through a hologram, a condenser lens, a laser mask, a transfer lens, and the like.

When a photosensitive solder resist composition is used as the solder resist composition, after a solder resist layer 136 is formed, a photoresist is placed on the solder resist layer 136 and exposed and developed. By performing the process, the solder resist layer 136 can be opened.

The portion of the conductor circuit 113 exposed by opening the solder resist layer 136 may be washed with a degreasing solution and then coated with a corrosion-resistant metal such as nickel, palladium, gold, silver, and platinum. desirable. Specifically, nickel-gold, nickel-
It is desirable to form the coating layer with a metal such as silver, nickel-palladium, nickel-palladium-gold, and the like. Among them, nickel-gold is particularly suitable. The coating layer can be formed by plating, vapor deposition, and electrodeposition. Among these, plating is preferable because of excellent uniformity of the coating layer.

According to the above method, the thickness of the nickel plating layer is preferably 0.5 μm to 20 μm, and particularly preferably 3 μm to 10 μm. If the thickness is less than 0.5 μm, it may be difficult to establish a connection between the solder bump and the nickel plating layer. Conversely, if the thickness exceeds 20 μm, the solder bumps 110 may not completely fit in the openings 15 and the solder bumps 110 may be easily peeled.

Next, a gold plating layer having a thickness of about 0.03 μm is formed on the nickel plating layer by electrolytic gold plating. As described above, the solder pad 137 is formed. For example, the solder pad 137 has a thickness of 25 to 150 μm.
After the solder paste is filled through the mask m, the solder bumps 110 are formed.

If the thickness of the mask is less than 25 μm, the amount of solder paste that can be filled in the solder pad 137 may be reduced. Therefore, when the printed wiring board 1 and an IC chip or the like are connected via the solder bumps 110 after the formation of the solder bumps 110, unconnected portions may be generated.

On the other hand, if it exceeds 150 μm, there is a possibility that the solder paste may be hardly removed from the openings formed in the mask. Therefore, the amount of the solder paste that can be filled in the solder pad 137 is reduced, and the multilayer printed wiring board 1 and the IC chip and the like are soldered to the solder bump 110.
There is a possibility that an unconnected portion may be generated when the connection is made via the. In addition, wraparound of the solder paste on the solder resist layer side of the mask (hereinafter, this side is referred to as the back side of the mask, and the opposite side is referred to as the front side of the mask) occurs. To the solder resist layer 136 and a short circuit in the obtained multilayer printed wiring board. Therefore, it is preferable that the thickness of the mask be limited to the above range. A more desirable thickness of the mask is 30 to 75 μm.

The material of the mask is not particularly limited, and examples thereof include those used for a print mask for manufacturing a printed wiring board and other print masks. Specific examples include a metal mask made of a nickel alloy, a nickel-cobalt alloy, SUS, or the like, and a plastic mask made of an epoxy resin, a polyimide resin, or the like. Examples of a method for manufacturing the opening of the mask include etching, additive processing, and laser processing. Among these, additive processing is desirable.

The opening formed in the mask may have a taper whose diameter is increased toward the solder resist layer 136. By forming the taper, the removability of the solder paste in the opening is improved.

It is preferable that the diameter of the opening formed in the mask is equal to or larger than the diameter of the solder pad 137. Increasing the diameter of the opening allows the solder pad 137 to be properly filled with the solder paste even if a slight displacement occurs between the solder pad 137 of the substrate 11 and the opening formed in the mask. It is. The diameter of the opening formed in the mask is not particularly limited, and may be appropriately selected in consideration of the size of the solder bump 110. Usually, the diameter is preferably 100 to 300 μm.

With the above-described mask placed on the solder resist layer 136, the solder paste is printed and filled into the plurality of openings from the top surface of the mask. When printing the solder paste, it is preferable that the mask be placed on the solder resist layer 136 so as to be tightly adhered thereto. By performing printing in a state where the mask and the solder resist layer 136 are in firm contact with each other, it is difficult for the solder paste to wrap around on the lower surface side of the mask due to bleeding. As a result, it is possible to prevent the surface of the solder resist layer 136 from being stained, and to prevent the obtained printed wiring board 1 from being short-circuited.

When printing the solder paste, a printing squeegee (not shown) is usually used. The material of the printing squeegee is not particularly limited, and materials generally used for printing a printed wiring board, such as rubber such as polyethylene, metal such as iron and stainless steel, and ceramic can be used. Among them, metal is preferable because it is difficult to reduce the weight and it is difficult for foreign matters to be mixed into the solder paste due to abrasion.

As the shape of the squeegee, there are various shapes such as a flat type and a square type. The squeegee having such a shape can be cut in time to improve the filling property of the solder paste. Although the thickness of the squeegee is not particularly limited, it is usually preferably 10 to 30 mm, more preferably 15 to 25 mm. This is because even if printing is repeatedly performed, warping and bending are unlikely to occur. Also,
For metal squeegees, the thickness is 50-300μ
m is desirable.

The solder paste may be printed by a closed squeegee unit. Examples of such a squeegee include an air press-fit type, a roller press-fit type, and a piston press-fit type.

The shape of the solder pad 137 in plan view is not particularly limited, and may be a circle, an ellipse, a square, or a rectangle. However, the stability of the shape of the solder pad 137 and the degree of design freedom (the solder pad 137) The space between them is widened, and wiring can be passed), and the circular shape is desirable from the viewpoint of the stability of the shape of the solder bump.

As a solder paste for forming the solder bumps 110, a solder paste generally used for a printed wiring board can be used. Specifically, Sn-Pb
(Eg, Sn: Pb in the range of 9: 1 to 6: 4), Sn—Ag, Sn—Ag—Cu
System, Sn-Cu system, and Sn-Sb system. The variation in the adhesive strength is small, and even under the heat cycle condition or the heat of mounting the IC chip, the adhesive strength of the pin 12 for connecting to an external electronic component such as a daughter board, which will be described later, does not decrease. It is possible to secure the electrical connection without causing it.
Among them, Sn-Pb is preferable. This is because cracks do not occur in the solder bumps even in a long heat cycle, and the bonding strength is excellent.

The melting point of the solder paste is 180 ° C. to 280 ° C.
It is desirable that If the melting point is below 180 ° C,
The required bonding strength of 2.0 kg / pin or more for the pin 12 cannot be secured, and the heat applied during the heat cycle condition or the mounting of the IC chip may cause the conductive connection pin to drop or tilt. On the other hand, the melting point is 280 ° C
Is exceeded, the resin insulating layer 143 and the solder resist layer 1
There is a possibility that the resin used for 36 may be dissolved, and the resin insulating layer 143 and the conductor circuit 113 may be peeled off, and the conductor circuit 113 may be disconnected. In addition, since the time required for heating is long, workability is deteriorated.

The viscosity of the solder paste is 100 Pa · S to 3
It is preferably set to 00 Pa · S. Viscosity is 10
If the pressure is less than 0 Pa · S, the solder bump 110 may not be able to be maintained in a desired shape. vice versa,
If the viscosity exceeds 300 Pa · S, there is a possibility that the solder paste cannot be efficiently filled into the opening 15.

Thereafter, the solder bumps 110 are fixed to the solder pads 137 by performing reflow under a nitrogen atmosphere at a temperature of 250 ° C. for a time of 30 seconds to 2 minutes. At this point, the solder bump 110 has a hemispherical shape. In addition, when performing the reflow, bubbles formed in the solder paste can be removed. The temperature at which the solder paste is reflowed is preferably 180 ° C to 280 ° C. This makes it possible to form the solder bumps 110 appropriately.

The temperature at which the solder paste is reflowed depends on the solder composition and is set according to the melting point of the solder. Melting point +
Temperatures between 0 ° C and + 30 ° C are desirable. This makes it possible to form the solder bumps 110 appropriately. Usually, it is preferable to add 180 ° C to 280 ° C. In the case where eutectic solder having a composition of Sn: Pb = 63: 37 is used, it is preferable that reflow is performed at 180 ° C. to 210 ° C.

Next, as shown in FIGS. 13A and 13B, the solder bumps 11 are
A flattening process of applying a heating and pressing process in the thickness direction of the top of the zero is performed. As a result, the tops of the solder bumps 110 are flattened to have a uniform height. By making the heights of the tops of the solder bumps 110 uniform in this way, the IC chip and the printed wiring board 1 can be securely joined. The lower jig 62 for pressing the lower surface 14 side of the printed wiring board 1 is preferably made of a hard and pressure-resistant metal material such as stainless steel. However, a ceramic material such as silicon nitride can be used as long as it is hard and pressure-resistant.

The temperature during the fluttering treatment is 60 ° C.
10 ° C lower than the melting point of the solder used
If there is a solidus line, it is preferable to set the temperature to 10 ° C. lower than the liquidus line). When the temperature is lower than 60 ° C., the solder bumps 110 are not sufficiently softened, so that a large pressing force needs to be applied, which may lead to breakage of the solder bumps 110. On the other hand, if the melting point of the solder is exceeded, the solder bump 110 is melted, and a suitable shape as the solder bump may be damaged. The eutectic solder (S
When (n: Pb = 63: 37) is selected, the temperature is desirably set to 100 ° C. to 160 ° C.

The pressing force in the fluttering process is 10 to
It is preferable to set within the range of 150 kgf / cm ² . This is because the top of the solder bump 110 can be flattened most efficiently within the above range. If the pressing force is less than 10 kgf / cm ² , the solder bump 1
There is a possibility that the top of 10 cannot be reliably flattened. On the other hand, if the pressing force exceeds 150 kgf / cm ² , the solder bump 110 may be damaged. In addition,
More preferably, the pressing force is set within a range of 30 to 100 kgf / cm ² .

The time during which pressure is applied by the upper jig 61 and the lower jig 62 is preferably set within 2 minutes, and more preferably, within 1 minute. If the pressing time exceeds 2 minutes, the productivity may decrease, and in addition, heat may be excessively transmitted, which may lead to breakage of the solder bump 110.

The height of the top of the solder bump 110 after the fluttering process (specifically, the height of the top based on the conductor circuit 113 exposed from the solder resist layer 136) is 0 μm to 100 μm. Preferably, the thickness is particularly 10 to 50 μm. If the protruding portion is less than 0 μm, the solder bump 110 and the terminal on the IC chip side are apt to be unconnected.
If it exceeds 0 μm, it is difficult to make the height of the top of the solder bump 110 uniform. In addition, the size of the solder bump 110 itself must be increased, and a short circuit is likely to occur after heating.

An IC using such a solder bump 110
By mounting the chip on the printed wiring board 1,
The C chip side and the printed wiring board 1 side are electrically connected. Note that reference numeral 16 in FIG. 13B represents a capacitor.

Next, a "division" is performed in which a substrate on which a plurality of (three or more) printed wiring boards 1 are formed is cut into two or more sheets.
After that, “singulation” is performed in which one divided substrate is cut into two or more substrates. By dividing the cutting process into two steps, dividing and dividing, even if the substrate is warped due to the heat history during the manufacturing process, the substrate can be cut at the correct position. The substrate can be prevented from being damaged. Therefore, there is no occurrence of cracking of the substrate or disconnection of the conductor circuit 113 during cutting. Further, since the substrate is cut exactly as designed, the solder bump 110
Is formed, the solder bumps 110 can be bonded at accurate positions.

On the substrate, a plurality of wiring board forming portions are arranged via the discarded ear portions. It is preferable that the discarded ears be cut and removed at the time of the division or at the time of singulation. As a result, chipping and damage of the substrate during the transfer of the substrate can be prevented. The discard ears may be provided only on one side surface of the substrate, or may be provided on a pair of opposite side surfaces. Also, it may be provided on all side surfaces surrounding the substrate. Preferably, the width of the discarded ear portion is 5 to 15 mm. If it is less than 5 mm, the edge of the substrate may be chipped or damaged during the transfer of the substrate.

The divided board is a board obtained by cutting the board, and has two or more wiring board forming portions on which the printed wiring board 1 is to be formed. The singulated substrate is a substrate obtained by cutting a divided substrate, and has only one wiring board forming portion on which the printed wiring board 1 is to be formed. The above division and singulation
Dicing, dicing router processing with a single blade or a multi-blade, or the like can be performed.

The area of the divided substrate is 5.1 × 10 ^-3 to
It is preferably in the range of 6.0 × 10 ⁻² m ² . 5.
If it is less than 1 × 10 ⁻³ m ² , the divided substrate may be damaged. If it exceeds 6.0 × 10 ⁻² m ² , the degree of warpage due to thermal history is large, and the accuracy of solder bump formation, IC chip mounting, and the like may be reduced. The area of the divided substrate is not only the area where the wiring board is formed,
In the case where a discarded ear portion described later is included, the area includes the discarded ear portion.

The area of the singulated substrate is 1.0 × 10 ^−4.
It is preferably 5.0 in the range of × 10 ^-3 m ^2.
If it is less than 1.0 × 10 ⁻⁴ m ² , the singulated substrate may be damaged. On the other hand, if it exceeds 5.0 × 10 ⁻³ m ² , there is a possibility that the accuracy of mounting an IC chip or the like may be reduced. The area of the above singulation was obtained by removing the discarded ears.
This is the area of only the wiring board formation part.

Next, the solder bumps 11 are formed on the lower surface 14 of the printed wiring board 1 (the connection surface with the daughter board and the motherboard).
The method of arranging the pins 0 and the pins 12 will be described in detail. First,
A solder paste as a conductive adhesive is printed on the solder resist layer 136 on the lower surface 14 of the printed wiring board 1 by the same method as described above.

The viscosity of the solder paste is 100 to 300 Pa
-Preferably set to S. Viscosity 100Pa ・
If it is less than S, the solder bump 110 may not be able to be maintained in a desired shape. Conversely, if the viscosity is 3
If it exceeds 00 Pa · S, there is a possibility that the solder paste cannot be efficiently filled into the opening 15.

Further, the pins 12 are supported by an appropriate pin alignment jig, and the pins 12 are brought into contact with the solder bumps 110 serving as a conductive adhesive in the solder pads 137 to perform reflow. It is fixed to 110 (FIG. 12).

Solder paste (Sn-Pb, Sn-Sb, Sn) formed on the lower surface 14 side of the printed wiring board 1 (the connection surface side with the daughter board and the motherboard) is used.
-Ag-Cu, etc.), a conductive resin, and a conductive paste. Among these, it is most preferable to form with solder. This is because the bonding strength with the pin 12 is excellent, and it is resistant to heat, and the bonding work is easy to perform.

The conductive adhesive has a melting point of 180 to 280 ° C.
It is good to use the thing of the range. As a result, pin 1
For example, 2.0 kg / pin or more is secured as the adhesive strength of No. 2, and the pins 12 do not fall off or tilt due to heat cycle conditions or heat applied during mounting, and electrical connection is also secured. If the melting point is less than 180 ° C., the conductive adhesive layer is likely to be re-melted and softened by heating after the bonding of the pins 12, so that it is difficult to secure sufficient adhesive strength to the conductive adhesive layer. . Therefore, there is a possibility that the inclination or displacement of the pin 12 and the destruction of the conductive adhesive layer cannot be avoided. On the other hand, when the melting point exceeds 280 ° C., the resin used for the resin insulating layer 143 and the solder resist layer 136 is dissolved, and the resin insulating layer 143 and the conductor circuit 113 may be peeled off, and the conductor circuit 113 may be disconnected. is there.

When the conductive adhesive is formed by soldering, the solder bumps 110 formed on the lower surface 14 side of the substrate (connection surface side with the daughter board and the motherboard) are connected to the upper surface 13 side of the printed wiring board 1 (IC chip connection). It is desirable to use one having a higher melting point than the solder bump 110 formed on the (side) side. Therefore, when an Sn—Pb (melting point: 180 ° C.) is used on the upper surface 13 side of the substrate 11, the lower surface 14
It is desirable to use a solder made of Sn—Sb (melting point 240 ° C.) on the side.

The reason is that when the IC chip is connected by reflowing the solder bumps 110 on the upper surface 13 later, if the melting point of the solder paste used on the lower surface 14 is the same as or lower than that on the upper surface 13, This is because the solder paste that fixes the pins 12 formed on the lower surface 14 is melted, and the pins 12 tilt or fall off.

As shown in FIG. 12, the solder pad 137 formed on the solder resist layer 136 is made of a solder resist layer (organic resin insulation) in which an opening 15 for partially exposing the solder pad 137 is formed. It is preferable that the fixing portion of the pin 12 is fixed to the solder pad 137 which is covered with the layer 136 and is exposed from the opening 15 via the solder bump 110 as a conductive adhesive.

As shown in FIG. 14, since this solder resist layer (organic resin insulating layer) 136 covers the periphery of the solder pad 137, the solder resist layer (organic resin insulating layer) 136 is mounted on the motherboard at the time of heat cycle. Even when stress is applied to the pin 12 during the
And delamination from the interlayer resin insulating layer 143 can be prevented. Also, it is difficult to peel off even when bonding between different materials such as metal and resin. Here, the multilayer printed wiring board 1 on which the interlayer resin insulating layer is formed is illustrated, but the present invention can be applied to a printed wiring board composed of only one substrate.

The solder paste printed as described above is subjected to reflow under a nitrogen atmosphere at a temperature of 250 ° C. for a time period of 30 seconds to 2 minutes, so that the solder bumps 110 are formed.
Is fixed in the opening 15. At this time, the solder bump 110 has a hemispherical shape at this time. Note that air bubbles formed in the solder paste when reflow is performed can be removed. The temperature for reflowing the solder paste is preferably from 180 to 280C. This makes it possible to form the solder bumps 110 appropriately.

After that, the pins 12 are attached to and supported by an appropriate pin holding device, and the fixing portions 44 of the pins 12 are brought into contact with the solder bumps 110 in the solder pads 137. Pin 1 above
2 basically comprises a head 125 and a leg 126. The leg portion 126 has a rod shape having a substantially circular cross section, and is generally insertable into a pin insertion hole of a socket provided on an external substrate such as a motherboard. As shown in FIG.
The head 125 is located on the upper end side of the leg 126. More specifically, the lower surface 125c of the head 125 is integrally connected to the upper end surface 126c of the leg 126. The disk-shaped head 125 has a larger diameter than the legs 126. The thickness of the head 125 is
It is considerably smaller than the length of the leg 126.
From the above, the conductive connection pin 12 of this example has a form to be called a T-shaped pin (or a nail-shaped pin).

The pin 12 of this embodiment is made of copper, copper alloy,
Selected from iron, tin, zinc, aluminum and precious metals,
It is formed using at least one or more kinds of conductive metals. Among them, it is particularly desirable to select an alloy such as Kovar having copper as a main component or an alloy having iron as a main component. The reason is that these alloys are highly reliable as metal materials for pins.

The upper surface 125b of the head 125 of the pin 12
At the time of pin bonding, it is arranged so as to face the solder pad 137 and is completely buried in the conductive adhesive layer. That is, the upper surface 125b of the head 125 is the surface to be joined of the pin 12.

The diameter of the head 125 of the pin 12 is preferably 0.8 to 1.2 times the diameter of the solder pad 137. If such conditions are set, the solder pads 137
This is because the bonding area in the inside is secured, so that the pins 12 can be easily set upright with respect to the multilayer printed wiring board 1.

Then, the pins 12 having the above configuration are connected to the substrate 1.
At the time of joining, the plurality of pins 12 are aligned in an upright state by a dedicated pin alignment jig. Thereafter, reflow is performed while the upper surface 125b of the head 125 is temporarily fixed to the solder bump 110 serving as a conductive adhesive layer, so that the conductive adhesive layer is re-melted, and the plurality of pins 12 are connected to the solder pads 137. Jointly.

Next, the pins 12 are fixed to the solder bumps 110 by performing reflow at a temperature of 250 ° C. for a time of 30 seconds to 2 minutes. Thereby, it is possible to prevent the solder from rising to the pins 12 at the time of reflow, and it is possible to appropriately mount (soldering) the pins 12.

After the solder paste is reflowed to form the solder bumps 110, the pins 12 are brought into contact with the solder bumps 110, and the pins are reflowed and the pins 12 are attached again when the solder paste is printed. This is to remove the bubbles that enter. Bubbles remaining in the solder are diffused or expanded by heat generated during operation of the electronic component. As a result, the connection strength of the pin 12 is reduced, which may affect the connectivity and reliability. Also,
In the worst case, the pins may come off when the daughter board socket is inserted or removed.

For this reason, when the solder paste is reflowed to form the solder bumps 110, bubbles formed in the solder paste are extracted, and then the pins 12 are mounted again by reflowing. By doing so, it is possible to prevent the solder from slipping onto the pin 12 during reflow.
The connection reliability of the printed wiring board 1 can be improved.

In this embodiment, the solder on the lower surface 14 is formed after the solder on the upper surface 13 is formed. However, the solder bumps 110 on both surfaces of the upper surface 13 and the lower surface 14 may be formed simultaneously. .

Next, on the solder resist layer 136 of the printed wiring board 1 manufactured through the above steps, various characters and symbols such as display characters for identifying products and recognition characters are printed by character printing or bar code printing. Performed by As a printing method, the printing position of the substrate jig and the mask is detected, and the printing is performed by laser processing or the like using a printing apparatus having automatic correction means.

With respect to the printed wiring board 1 produced through the above-described steps, the continuity test of the wiring circuit and the capacity test of the mounted capacitor 16 and the pins connected to the printed wiring board 1 as shown in Embodiment 1 are performed. Twelve appearance inspections are performed.

[Brief description of the drawings]

FIG. 1 is a top view of a printed wiring board inspection apparatus according to a first embodiment.

FIG. 2 is a top view of a printed wiring board inspection apparatus and peripheral equipment according to the first embodiment.

FIG. 3 is a cross-sectional view of the printed wiring board according to the first embodiment.

FIG. 4 is a top view illustrating a method for mounting a printed wiring board on a pallet in the first embodiment.

FIG. 5 is a top view illustrating a state in which a printed wiring board is mounted on a pallet in the case where no temporary placement stage is provided in the first embodiment.

FIG. 6 is an explanatory cross-sectional view of the printed wiring board and a continuity tester before inspection in the first embodiment.

FIG. 7 is an explanatory cross-sectional view of a printed wiring board and a continuity tester at the time of inspection in the first embodiment;

FIG. 8 is a cross-sectional explanatory view showing (A) a state before the printed wiring board is placed on the inspection jig and (B) a state in which the inspection is performed in the first embodiment.

FIG. 9A shows a state before mounting a printed wiring board having bent pins on an inspection jig in the first embodiment,
(B) Explanatory sectional drawing showing the state which detected the bending of the pin in the inspection, respectively.

FIG. 10 is a top view of the printed wiring board and the appearance inspection device during inspection according to the first embodiment.

FIG. 11 (A) shows a state before mounting a printed wiring board having a pin lift on an inspection jig according to the first embodiment.
(B) Explanatory sectional drawing showing the state which detected the pin lift in the test | inspection, respectively.

FIG. 12 is an explanatory sectional view of a printed wiring board according to the second embodiment.

13A is a perspective explanatory view of the fluttering process and FIG. 13B is a cross-sectional view taken along line AA of FIG.

FIG. 14 is an explanatory cross-sectional view of a printed wiring board around pins in Example 2.

15A is a plan view and FIG. 15B is a cross-sectional view of a printed wiring board on which electronic components are mounted in a conventional example.

FIG. 16 is an explanatory cross-sectional view of a printed wiring board having bent pins in a conventional example.

[Explanation of symbols]

 1. . . Printed wiring board, 11. . . Substrate, 12. . . 1. pins (conductive connection terminals); . . Inspection device, 20. . . Rotary table (transporting means), 21. . . Loading stage, 22. . . Continuity inspection stage, 23. . . Capacity inspection stage, 24. . . Appearance inspection stage, 25. . . Carry-out stage, 26. . . Temporary stage, 31. . . Loading machine, 32. . . Continuity tester, 33. . . Capacity inspection machine, 34. . . Appearance inspection machine, 35. . . Unloader,

Continuation of the front page F term (reference) 2F065 AA01 AA31 AA51 BB01 BB05 CC01 CC28 DD02 DD06 FF02 GG04 HH04 HH15 JJ01 JJ15 PP13 QQ04 SS04 2G011 AA01 AB08 AC09 AE01 2G014 AA13 AB59 AC10 2G132 AA20AF79 CB21 DA02 DA11 DA30

Claims (6)

[Claims] In a method of inspecting a printed wiring board on which electronic components and a plurality of conductive connection terminals are erected on a substrate having a circuit, the printed wiring board to be inspected is placed on a substrate set on a transfer means. A loading process for loading into the jig,
An electrical inspection step of conducting a continuity inspection of the printed wiring board and a capacitance inspection of the electronic component, an appearance inspection step of performing an appearance inspection of the conductive connection terminal, and a defective product in the electrical inspection step or the appearance inspection step Discharging the printed wiring board from the transfer means, and separating the printed wiring board determined to be non-defective from the transfer means to the next step in each stage, and performing the separation by the transfer means. A method for inspecting a printed wiring board, comprising transferring the printed wiring board to each of the stages. 2. A method according to claim 1, wherein said transfer means is a rotary table. 3. The electric inspection step and the appearance inspection step according to claim 1 or 2, wherein a plurality of the printed wiring boards are inspected in a set, and only a part of the plurality of printed wiring boards is inspected. If it is determined in the inspection process that the printed circuit board is non-defective, in the separating step, the non-defective printed circuit board is temporarily placed on a temporary placement stage, and then a part of a set of a plurality of printed circuit boards to be inspected is checked. A method for inspecting a printed wiring board, characterized in that when only the non-defective product is a non-defective product, the non-defective printed wiring board and the printed wiring board temporarily placed on the temporary placement stage are brought out together. 4. An inspection apparatus for inspecting a printed wiring board on which electronic components and a plurality of conductive connection terminals are erected on a substrate having a circuit, wherein the inspection apparatus performs a continuity inspection of the printed wiring board. A continuity tester for performing a continuity test, a capacity tester for performing a capacity test of the electronic component, an appearance tester for performing a visual test of the conductive connection terminal, and a transfer means for holding and transferring the printed wiring board; The continuity inspection machine,
A capacity inspection machine and a visual inspection machine are provided on each stage arranged along the transfer means, and the transfer means is configured to transfer the printed wiring board to each of the stages. A printed wiring board inspection apparatus, characterized in that: 5. An apparatus according to claim 4, wherein said transfer means is a rotary table. 6. The inspection device according to claim 4 or 5, wherein the inspection device has a temporary placement stage for temporarily placing a non-defective printed wiring board. When a plurality of printed wiring boards are inspected in a set and only a part of them is judged to be good by each inspection machine, the unloader temporarily places the good printed wiring boards on the temporary placement stage. If only a part of a plurality of printed wiring boards to be inspected thereafter is non-defective, the non-defective printed wiring board and the printed wiring board temporarily placed on the temporary placement stage are separated. An inspection device for a printed wiring board, wherein the inspection device is configured to be carried out together.