JPS58146866A - Conductive pattern inspection method - 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] (6) Invention! The present invention relates to a method for inspecting disconnections in a large number of conductive patterns disposed close to each other on an insulating substrate, such as electrodes of a gas discharge display panel or wiring of a printed circuit board.

(b) Prior Art and Comparison Points Generally, methods such as visual inspection, microscopic observation, and continuity testing using direct current are used to inspect new conductive patterns such as electrodes of gas discharge display panels. However, methods using visual inspection or microscopic observation require a lot of work time and labor, and the operator's visual fatigue is severe, leading to inspection errors due to oversights.

In addition, in a DC conduction tester, for example, one end of a large number of linear electrodes arranged in parallel on a glass substrate is connected together, a DC voltage is applied to the common connection, and the DC voltage is detected at the other end of each electrode. A method has been adopted in which the presence or absence of continuity is detected by directly contacting the probe with a probe. By the way, in this method, it is necessary to maintain a very good contact state between each electrode and the tip of the seal, but some of the hundreds of electrodes may develop poor contact. It was sometimes said that the contact was broken. One cause of this poor contact could be foreign matter, such as photoresist, on the electrode. As a countermeasure, polish the electrode end to the extent that it does not damage it. However, it is not a reliable preventive measure. Furthermore, depending on the electrode material and its thickness, polishing or the like may not be possible, making it difficult to conduct reliable inspections during downtime. Furthermore, it is often necessary to perform a disconnection test with the electrode covered with a thin dielectric film, but in such cases, continuity testing using direct current is not possible unless the dielectric film is removed. Therefore, a continuity testing method using alternating current has also been proposed in which alternating current voltage is applied to one end of the electrode and the alternating voltage is detected from the other end through a dielectric layer.

In this method, in order to prevent erroneous inspections due to capacitive coupling between m-electrode phase tiles, for example, an AC voltage is applied to every other electrode and the other * electrodes are grounded. It was necessary to repeat the odd-numbered electrode test twice.

Furthermore, it requires a special connector for applying alternating current voltage and grounding to every other electrode, and furthermore, it cannot be applied to a group of electrodes in which one end of each electrode is originally connected in common.

(C) Purpose of the Invention The present invention is based on the above-mentioned points, and is capable of easily and reliably disconnecting a large number of conductive patterns arranged on an insulating substrate.
The object of the present invention is to provide a method for inspecting a conductive pattern that can be inspected in a short period of time.

(Both Structures of the Invention The method for inspecting a conductive pattern according to the present invention includes a first power source that applies an alternating current (J) to one end of a large number of conductive patterns to be inspected that are arranged close to each other on an insulating substrate, and a a conductive member for capacitive coupling disposed to be electrostatically coupled to the conductive pattern to be inspected; and an AC signal having a mode different from the AC signal of the first power source to the conductive member for capacitive coupling. It is provided with a power supply of 2 to 1 and a means for detecting an alternating current signal from the other end of the conductive pattern to be inspected, and according to the mode of the AC signal detected by the detection means, The feature is that a disconnection of the conductive pattern is detected.

(-) Embodiments of the Invention Below, the application of embodiments of the present invention to the electrode inspection of gas discharge display panels will be explained with reference to the drawings. Figure 1 is for explaining the method of inspecting conductive patterns according to the present invention. 1 is a conceptual diagram of the main parts of the gas discharge display panel, and 1 is one of the glass substrates constituting the gas discharge display panel.

For example, a large number of linear electrodes 2 are arranged side by side at equal intervals on the surface of the glass substrate 1, and one end of each electrode 2 is taken out on one side of the substrate 10 (lower end in the figure). and each electrode 2
One end is commonly connected to the connecting wire 8 and connected to the first power source 4 for inspection.In the state shown in Figure 0, each electrode becomes the electrode to be inspected, and an insulating sheet 6 (for example, a (Reestercy) Or! A conductive member 6 for electrostatic coupling, such as a conductive rubber sheet, a metal mesh sheet, or a metal plate, is disposed via a conductive material 6 (e.g. conductive rubber sheet, metal mesh sheet, metal plate, etc.), and the conductive member 6 for electrostatic coupling and each electrode 2 are electrostatically coupled. . A second power source 7 for inspection is connected to the electrostatic coupling conductive member 6, and a voltage V, % frequency/1 is applied to the electrostatic coupling conductive member 6.
AC signals are applied. That is, the signals sent from the first power source 14 and the second IIt source 7 are, for example, AC signals with different modes of voltage and frequency, and in the case of this embodiment, the voltage of the first power source 4 is Z booklet 9 train ζ) Ken 1 is V, <Is<ft
It is set to . Also, a portion 8 indicated by a dotted line is a means for detecting an AC signal from the other end of each electrode 2 to be inspected, and in the case of this embodiment, the detection means 8 is an AC probe 8@
, amplifier 赫, frequency discriminator 8C and recorder 8I! Consisting of Note that the tip of the AC probe should not be connected to a conductor made of slippery material such as plastic or glass. It is covered with a body layer.

Now, in the above configuration, the AC probe is moved over the other end of each electrode 2 in the direction shown by the solid arrow A. Assuming that the point indicated by D on the electrode 2 is a # line, when the AC probe is on the non-disconnected electrode 2,
The AC probe 86 can detect a strong AC signal from the first power source 4 .

However, when the AC pin 4-186 is on the disconnected line 11g, the AC signal on the jll line 114 appears only through the stray capacitance coupling between the S* electrodes, but rather through the stray capacitive coupling from the capacitive coupling conductive member 6. The AC signal from the second power source 7 is strongly detected through the coupling capacitance.

Therefore, the output level of the frequency discriminator ν is higher when the AC pulse ν-186 is on the disconnected electrode 2 than when it is on each non-disconnected electrode 2, and the voltage recorded on the recorder U is higher. Based on the level, disconnected electrodes can be detected.

Note that this example describes the case where each electrode type is arranged in an exposed manner on the surface of the Gates substrate 1.
If the surface of each electrode 2 is coated with a thin dielectric film, the insulating sheet may be omitted, and the tip of the AC power supply may be an exposed conductor. . When using an AC conductor with an exposed conductor tip, place a polyethylene sheath on the AC conductor to prevent damage to the electrode or the dielectric film covering its surface. 1 may be slid, or the same effect can be obtained by floating the electrode 2 with a slight gap so as to electrostatically engage the other end of each electrode 2. Also insulation sheet)
6, the electrostatic coupling conductive member 6 is connected to each electrode 2.
By placing it floating above with a gap,
The electrostatic coupling conductive member 6 and each electrode 2 can also be electrostatically coupled.

Further, the conductive member for f# electrical coupling may be fixed as described above, but it may also be movable so that it moves along with the AC probe over the electrode to be tested, as shown in FIG. 2 and 854. . That is, number 8 in FIG. 2 is an AC pwerp, and number 9 is a roller made of conductive rubber, for example. The conductive reeler 9 is integrally assembled with the AC probe 81 by a conductive framework 1O, a support portion 11, and an insulating support body 12. And each gold electrode to be tested! A conductive loaf 9 moves along with the AC probe above. At this time, if the electrode 2 to be inspected is covered with a dielectric film, the conductor 1 route 9 may be rotated over the dielectric film. However, when each electrode 2 is exposed, an insulating sheet (such as a polyester sheet or
(not shown) may be laid and the conductive wire 9 may be rotated thereon, or the surface of the conductive wire 9 may be coated with an insulator depending on the case. Also, 13 in Figure 1
is a conductive curtain made of a thin plate spring made of phosphor bronze, for example, and the conductive curtain 13 is integrally assembled with the AC probe 86 by an insulating support 12. The conductive curtain 13 moves over each electrode 2 as the AC puden-pu moves.
moves. In this case, the surface of the conductive curtain 13 can also be coated with an insulator if necessary.
Instead, a conductive brush made of a collection of elastic wires can also be used. Furthermore, in the above-mentioned embodiment, a case was described in which the voltage and frequency of the AC signal of the first and second power supplies were varied to change the mode of the AC signal.
Not limited to this, it is possible to vary AC signal modes such as voltage, frequency or phase, or two of them.
You may change more than one type at the same time. In addition, in the present invention, No. 1! When making the AC signal of the power source match the mode of the AC signal of the first power source, the AC signal of the second power source is set to zero volts,
In other words, it is possible to maintain the potential of the conductive member for electrostatic coupling at the ground potential, and conversely, it also includes setting the first power source to zero volts with respect to the second power source. When the surface of the overlapping electrode to be inspected is covered with a dielectric film, a liquid conductor such as an electrolytic solution can also be used as the conductive member for electrostatic coupling. Furthermore, the mode of the AC signal detected by the detection means can be indicated not only by a recorder but also by any method such as using a lamp, a buzzer, or a voltage needle. It is also possible to mark the product as defective. In addition, as a method for commonly connecting each electrode, a crimp connector, conductive paste, or conductive rubber band can be used, and originally one end of each electrode is common! Those that have undergone M can be inspected as they are.

Furthermore, in the above-mentioned embodiment, the conductive member for electrostatic coupling was placed between the AC probe and the object to be inspected at one end of the pole, that is, the feeding point. In other words, the positional relationship between the AC pump and the conductive member for electrostatic coupling in the above-described embodiments can be reversed.

The gist of the present invention is not limited to gas discharge display panels, but similar effects can be obtained even when applied to electrode inspections of other display panels such as liquid crystal display panels, wiring inspections of printed boards, etc.

ω Effects of the Invention As is clear from the above explanation, the present invention can easily, reliably, and quickly detect disconnection of a large number of electrodes arranged close to each other on an insulating substrate, improving inspection efficiency and improving reliability of inspection. It is extremely effective in improving sexual performance.

[Brief explanation of drawings]

The first wJ is a conceptual diagram of main parts for explaining an embodiment in which the present invention is applied to an electrode disconnection inspection of a gas discharge display panel,
FIGS. 8 and 8 are perspective views conceptually showing essential parts for explaining the structure of another embodiment of the electrostatic coupling conductive member used in the present invention. In the figure, l is the glass substrate, 2 is the electrode to be inspected 4 is the first
b is an insulating sheet, 6 is a conductive member for electrostatic coupling, 7 is a W source,
8 is a second power source, 8 is an AC signal detection means, 84j is an AC converter, 8b is an amplifier, C is a frequency discriminator, diagonal is a refuder, 9 is a conductive roller, and 13 is a conductive curtain. Figure 1 Figure 2 N' 3e21

Claims (1)

[Claims] A first power supply that applies an alternating current signal to one end of a large number of conductive patterns to be inspected that are arranged close to each other on an insulating substrate; a conductive member for capacitive coupling, an eighth power source that applies an AC signal having a mode different from that of the AC signal of the first power source to the conductive member for capacitive coupling, and the other end of the conductive pattern to be inspected. means for detecting an alternating current signal from the detecting means, and a disconnection of the conductive pattern to be inspected is detected based on the waveform of the alternating current signal detected by the detecting means. inspection method.