JPH07270477A - Defect detection method and defect detection device for linear electrode - Google Patents

Abstract

PURPOSE:To efficiently detect the break of a liner electrode. CONSTITUTION:Probe electrodes P1 to P4 are arranged to cross each other separatedly in grade, in order to examine the wire break of liner electrodes E1 to E5. Also, capacitive coupling is applied to each crossing point of the electrodes E1 to E5, and P1 to P5. For inspecting the center hatching section of the electrode E3, a voltage feed selector circuit 40 is selected to apply the same AC voltage to the electrodes P2 and P3 mutually inverted phase. In this case, a voltage detecting selector circuit 50 is selected to connect the left end of the electrode E3 to a detection circuit 100, while the left ends of other liner electrodes are grounded. The circuit 100 judges that no wire break exists, if no voltage fluctuation is observed at the left end of the electrode E3, and that a wire break exists, if the voltage fluctuation is observed. According to this construction, a wire break can be detected for all zones of the electrodes E1 to E5 on the operation of the circuits 40 and 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defect detecting method for a linear electrode and a defect detecting device, and more particularly to a defect for detecting a defect in a display linear electrode formed on a substrate of a flat display device such as a plasma display device. The present invention relates to a detection method and a defect detection device.

[0002]

2. Description of the Related Art In a device for handling an image, such as a plasma display device, a liquid crystal display device, an image sensor, etc., a substrate on which a large number of linear electrodes are formed is used. For example, in a plasma display device, a large number of linear electrodes are arranged in a horizontal direction on a first substrate, a large number of linear electrodes are arranged in a vertical direction on a second substrate, and these two substrates are opposed to each other. Thus, a grid pattern is formed by a large number of linear electrodes. Then, a predetermined voltage is applied between an arbitrary one linear electrode on the first substrate and an arbitrary one linear electrode on the second substrate arranged so as to face the linear electrode. Then, discharge occurs at the intersection of the two linear electrodes to which the voltage is applied. If a plasma light emitting material is filled between both substrates, plasma light emission occurs due to discharge generated in a minute portion where two linear electrodes intersect, and display for one pixel is performed.

Generally, in order to improve the performance of a display device, it is necessary to increase the resolution. In order to improve the resolution, the width and pitch of the linear electrodes must be made finer and finer. Moreover, the demand for large display devices is increasing year by year. Therefore, it is necessary to provide a substrate in which very thin and long linear electrodes are arranged at a fine pitch. For example, in a large-sized plasma display device currently manufactured, a width of 100 μm,
A substrate in which a large number of very thin and long linear electrodes having a length of 1 m are arranged at a fine interval of an average pitch of 0.65 mm is used.

When manufacturing a substrate in which a large number of such fine linear electrodes are arranged, it is very important to detect whether or not a defect such as disconnection has occurred in each linear electrode.
If the disconnection occurs even at one place, the pixels on the screen do not emit light in a row, and the display device cannot perform the correct function. Therefore, conventionally,
For each of the linear electrodes, a probe electrode was brought into contact with both ends of the linear electrode to conduct a continuity test.

[0005]

However, the work of conducting the continuity test one by one for a large number of linear electrodes requires a great deal of labor and time. As mentioned above,
The demand for large-sized display devices with high resolution is expected to increase more and more, and the number of linear electrodes formed on one substrate will increase more and more. Therefore, manually conducting the continuity test for each of the linear electrodes as described above is extremely inefficient in practical use. Moreover, in the conventional detection method in which the probe electrodes are brought into contact with both ends of the linear electrode and the continuity test between the probe electrodes is performed, even if a defect is found, its position cannot be specified. In other words, if the result that there is no electrical connection between both probe electrodes is obtained, it can be recognized that any part of the linear electrode currently being detected is open, but You cannot know where the place is. At present, linear electrode substrates for plasma display devices are expensive to manufacture, so it is economical to discard the entire substrate just because some defects were found in the final inspection process. I can't do it for some reason. Therefore, when the presence of a defect is recognized, it is necessary to perform work to repair the defect. However, since the conventional defect detection method cannot know the position of the defect, it is necessary to specify the position of the defect by another method. Conventionally, in order to specify the position of such a defect, an inspection is performed using a microscope or the like, or an image of the linear electrode pattern is taken into a computer, and the defective part is specified by calculation processing in the computer. . However, the task of identifying a defect position using a microscope requires a great deal of labor, while the method of identifying a defect position by image processing by a computer has a heavy calculation processing load.
A great deal of labor is required to complete an image processing program that functions practically.

Therefore, it is an object of the present invention to provide a defect detecting method and a defect detecting device for a linear electrode capable of efficiently detecting a defect in the linear electrode.

[0007]

[Means for Solving the Problems]

(1) A first aspect of the present invention is a method for detecting a defect in a linear electrode extending in a predetermined direction, wherein the first probe electrode and the second probe electrode are provided at positions on both sides of a detection target section of the linear electrode. The probe electrodes are arranged at a predetermined interval from the linear electrodes, respectively, and the first AC voltage and the second AC voltage having the same frequency and amplitude and having the phases inverted from each other.
Voltage that is induced at one end of the linear electrode when the first AC voltage is applied to the first probe electrode and the second AC voltage is applied to the second probe electrode. The fluctuation is measured, and the presence or absence of a defect in the detection target section is detected based on the amplitude of the voltage fluctuation.

(2) A second aspect of the present invention is the above-mentioned first aspect.
In the detection method according to the aspect (1), elongated electrodes are used as the first probe electrode and the second probe electrode, and one end of each probe electrode is fixed to a predetermined reference potential via a terminating resistor. An AC voltage is applied to each of the other ends, the voltage fluctuation detection end of the linear electrode is fixed to a predetermined reference potential via a resistance element, the voltage fluctuation detection end is connected to an amplifier, and based on the output voltage of this amplifier. The presence or absence of defects is detected.

(3) A third aspect of the present invention is a method for detecting a defect in a plurality of linear electrodes extending along a first direction in a first plane and arranged substantially parallel to each other. In a second plane parallel to the first plane, a plurality of elongated probe electrodes that extend along a second direction substantially perpendicular to the first direction and are arranged substantially parallel to each other are provided. , A first AC voltage and a second AC voltage having a frequency and an amplitude that are equal to each other and are in a phase-inverted relationship with each other are provided, and one of the plurality of linear electrodes is One of the pair of probe electrodes located on both sides of the detection target section of the one linear electrode to be detected is defined as the first probe electrode and the other is defined as the second probe electrode. The first probe electrode While applying an alternating voltage and applying a second alternating voltage to the second probe electrode,
The voltage fluctuation induced at one end of the linear electrode to be detected is measured, and the presence or absence of a defect in the detection target section is detected based on the amplitude of this voltage fluctuation.

(4) The fourth aspect of the present invention is the above-mentioned third aspect.
In the detection method according to the second aspect, one end of each probe electrode is fixed to a predetermined reference potential via a terminating resistor, and an AC voltage is applied to the other ends of the first probe electrode and the second probe electrode, respectively, and detection is performed. The voltage fluctuation detection end of the target linear electrode is fixed to a predetermined reference potential via a resistance element, the voltage fluctuation detection end is connected to an amplifier, and the presence or absence of a defect is detected based on the output voltage of this amplifier. It is the one.

(5) A fifth aspect of the present invention is an apparatus for detecting a defect in a plurality of linear electrodes extending along a predetermined direction in a predetermined plane and arranged substantially parallel to each other, It has a flat support substrate, a plurality of elongated probe electrodes extending along a predetermined direction on the support substrate and arranged substantially parallel to each other, and an insulating film formed so as to cover the probe electrodes. A probe substrate, a voltage supply circuit that supplies a first AC voltage and a second AC voltage that have the same frequency and amplitude, and are in a phase-inverted relationship with each other, and a pair of probe electrodes are selected from a plurality of probe electrodes. Then, a voltage supply selection circuit that supplies a first AC voltage to one of the selected probe electrodes and a second AC voltage to the other, and one linear electrode from the plurality of linear electrodes. A voltage detection selection circuit that selects a pole and extracts a voltage fluctuation induced at one end of the selected linear electrode, and a pair of selected pairs of the selected linear electrodes based on the extracted voltage fluctuation. And a detection circuit for detecting the presence / absence of a defect in the corresponding portion between the probe electrodes.

(6) The sixth aspect of the present invention is the above-mentioned fifth aspect.
In the detection device according to the aspect, a phase delayer that delays the phase of the AC signal obtained from the voltage supply circuit by a predetermined delay time and a signal from the phase delayer among the voltage fluctuations extracted from the voltage detection selection circuit. Based on the signal from the phase delay device, only the negative component is extracted from the first filter that extracts and outputs only the positive component based on A second filter for inverting and outputting the second filter, an output of the first filter and a second filter
An adder for adding the output of the filter and the detector, and a defect detection device for a linear electrode, characterized in that the presence or absence of a defect is detected based on the output of the adder.

[0013]

[Operation] 1 above the linear electrode to be detected
When one probe electrode is arranged, a capacitive element will be formed in a portion where both electrodes overlap in a plane. Therefore, when a pair of probe electrodes are arranged at a distance from each other, a capacitive element is formed in each overlapping portion of each probe electrode and the linear electrode. Generally, in a capacitive element, if an AC voltage is applied to one electrode,
This AC component is transmitted to the other electrode that is capacitively coupled,
An AC voltage is also induced in the other electrode. Therefore, if an AC voltage is applied to the pair of probe electrodes, an AC voltage will be induced in each corresponding portion of the linear electrodes capacitively coupled to them. At this time, if the phases of the AC voltages applied to the pair of probe electrodes are set to be in a mutually inverted relationship, the polarities of the voltages induced in the corresponding portions on the linear electrode side are opposite to each other. That is, if positive charge is induced in the portion corresponding to the first probe electrode, negative charge is induced in the portion corresponding to the second probe electrode.

Now, the frequencies and the amplitudes of the AC voltages applied to the pair of probe electrodes are made equal, and only the phases are different (inverted). Then, at each moment,
The positive charge amount and the negative charge amount induced in each corresponding portion on the linear electrode side are equal. Therefore, in the normal case where there is no disconnection defect in the linear electrode, the induced charges cancel each other out, and the charge is not generated in the linear electrode in total. However, if there is a disconnection defect in the linear electrode in the section sandwiched by the pair of probe electrodes, the positive charge-induced portion and the negative charge-induced portion are electrically separated. Therefore, both charges are not canceled out. Therefore, a voltage fluctuation having the same frequency as the AC voltage applied to the probe electrode is observed at one end of the linear electrode. Therefore, based on this voltage fluctuation, a predetermined portion of the linear electrode (section sandwiched by a pair of probe electrodes)
The presence or absence of defects can be detected.

A large number of linear electrodes are arranged on a substrate used for a plasma display device or the like. When detection is performed on such a large number of linear electrodes, the linear electrodes are A large number of probe electrodes may be arranged so as to extend in the direction orthogonal to the longitudinal direction. In this case, if one of the many linear electrodes to be detected is selected and the voltage fluctuation occurring at one end of this one linear electrode is observed, detection based on the above-described principle is performed. 1
It can be done sequentially book by book. Further, among a large number of probe electrodes, by selecting a pair and applying an alternating voltage, it is possible to determine the presence or absence of a defect for each section sandwiched by the selected pair of probe electrodes, If there is a defect, its position can be specified.

[0016]

The present invention will be described below based on illustrated embodiments.

<Basic Principle of the Present Invention> First, the basic principle of the linear electrode defect detection method according to the present invention will be described. Now, as shown in FIG. 1, consider a case where defect detection is performed on a detection target electrode E that extends linearly in the lateral direction from the left end a to the right end b. The detection method of the present invention uses a pair of probe electrodes. Here, a probe electrode 1 that extends linearly in the vertical direction from a lower end c to an upper end d in the figure, and a probe electrode 2 that extends linearly in the vertical direction from a lower end e to an upper end f.
Consider an example using and. Although shown in plan in the figure, the probe electrodes 1 and 2 are arranged above the detection target electrode E (that is, in the direction perpendicular to the paper surface). In other words, the detection target electrode E and the probe electrodes 1 and 2 intersect at the points g and h in a plane, but in reality,
The probe electrodes 1 and 2 are in a state of floating with a predetermined distance from the detection target electrode E. The pair of probe electrodes 1 and 2 have the same shape and the same size, and are arranged at the same angle (right angle in this example) with respect to the detection target electrode E while keeping the same distance.

Further, one ends d and f of the probe electrodes 1 and 2
Are grounded via terminating resistors R1 and R2, respectively. On the other hand, the AC voltage generated by the AC power supply G is applied to the other ends c and e of the probe electrodes 1 and 2 via the buffer 3 and the inverting buffer 4, respectively. That is, the AC voltages applied to the probe electrodes 1 and 2 have the same frequency and the same amplitude, and only the phases are inverted (having a phase difference of 180 °). on the other hand,
The left end a of the detection target electrode E is grounded via the resistance element R0, and the potential of the left end a is amplified by the amplifier 5 and output.

Here, paying attention to the structure at the intersection of the points g and h, it means that the partial area of the detection target electrode E and the partial areas of the probe electrodes 1 and 2 face each other in the three-dimensional space. . That is, the conductive regions having a certain area are arranged to face each other with a predetermined interval, and the capacitive element is electrically formed. Therefore, when an AC voltage is applied to the probe electrodes 1 and 2, a voltage variation is induced in each partial region of the detection target electrode E due to capacitive coupling based on this capacitive element. Therefore, let us consider in detail what kind of phenomenon occurs electrically in such a detection system.

FIG. 2 is an equivalent circuit of the detection system shown in FIG. As described above, the detection target electrode E and the probe electrode 1,
Capacitance elements are formed at the intersections g and h with the two points. In this equivalent circuit, these capacitance elements are C1 and C2.
It is represented by. As described above, the AC voltage generated by the AC power supply G is applied to the probe electrodes 1 and 2 via the buffer 3 and the inverting buffer 4, respectively. This is equivalent to the capacitive elements C1 and C in the equivalent circuit of FIG.
2 means that an alternating voltage is applied to the upper electrode. Here, for convenience of explanation, consider an instantaneous state. Now, as shown in FIG. 2, a state in which a positive charge is applied to the electrode (probe electrode 1) above the capacitive element C1 and a negative charge is applied to the electrode (probe electrode 2) above the capacitive element C2. Considering the above, a negative charge is induced at the point g of the detection target electrode E, and a positive charge is induced at the point h. Since the alternating voltage applied to the probe electrodes 1 and 2 has the same frequency and the same amplitude, the negative charge amount induced at the point g and the point h at a certain moment. The amount of positive charge is equal to. Therefore, as shown in FIG. 2, assuming that there is no defect in the detection target electrode E, since the point ab is in the conductive state, the negative charge generated at the point g and
The positive charges generated at the point h are offset by each other, and no potential fluctuation occurs in the detection target electrode E as a whole. Although an AC voltage is applied to the probe electrodes 1 and 2, in each instantaneous state, positive and negative charges are canceled on the detection target electrode E, so that even if a change over time is observed, the detection target The voltage fluctuation does not occur in the electrode E as a whole. Therefore, no signal output is obtained from the amplifier 5 (actually, some voltage is output due to the noise component).

Then, what if the defect occurs in a part of the electrode E to be detected? Here, first, let us consider a case where a disconnection occurs at a predetermined position x1 between points ag as shown in FIG. In this case, since the points gh are electrically connected to each other, the induced positive and negative charges are canceled out. Therefore, the amplifier 5
No potential fluctuation is detected from. Similarly, as shown in FIG. 4, consider a case where a disconnection occurs at a predetermined position x2 between points hb. In this case as well, the points gh are electrically connected to each other, so that the induced positive and negative charges are canceled out. Therefore, no potential fluctuation is detected from the amplifier 5.

However, what will happen if a disconnection occurs at a predetermined position x3 between the points gh as shown in FIG. In this case, since the point g and the point h are not electrically connected, the negative charge generated at the point g and the positive charge generated at the point h are not canceled.
Therefore, the negative charge generated at the point g is
Will be output as a negative voltage. The state of FIG. 5 is an instantaneous phenomenon, but in reality, since an alternating voltage having a predetermined frequency is supplied to the probe electrodes 1 and 2, the charges generated at the point g are alternately positive and negative. It becomes a thing. Therefore, from the amplifier 5, the AC power supply G
An AC signal of the same frequency (phase is slightly delayed) will be output.

In summary, when there is no disconnection as shown in FIG. 2 and as shown in FIGS. 3 and 4 when the disconnection occurs in a portion other than the section gh, the amplifier 5 is constant. Although the reference voltage value continues to be output, it can be seen that the AC voltage having the same frequency as that of the AC power supply G is output from the amplifier 5 when the disconnection occurs in the section gh as shown in FIG. . Conversely, when the output of the amplifier 5 is the reference voltage value, at least the pair of probe electrodes 1,
It can be recognized that there is no disconnection in the section gh sandwiched by 2 and when the AC signal of the same frequency as the AC power supply G is output from the amplifier 5, the section gh sandwiched by the pair of probe electrodes 1, 2. It can be recognized that there is a disconnection inside.

Thus, based on the output of the amplifier 5,
Since it is possible to determine the presence / absence of a wire break in the section gh sandwiched between the pair of probe electrodes 1 and 2, in FIG. By observing the output, it becomes possible to detect disconnection of the detection target electrode E over the entire length from the left end a to the right end b.

The terminating resistors R1 and R2 connected to one ends of the probe electrodes 1 and 2 are not necessarily required in principle. That is, in the equivalent circuit diagrams of FIGS. 2 to 5, even if the terminating resistors R1 and R2 are omitted, the detection based on the above principle is possible. However, the termination resistance R
If 1 and R2 are omitted, the potentials of the probe electrodes 1 and 2 become unstable due to disturbance. Therefore, in practice, it is preferable to fix one end of the probe electrodes 1 and 2 to a predetermined reference potential (ground potential in this example) via the terminating resistors R1 and R2.

<Specific Structure of Detecting Device> Next, the structure of a specific detecting device capable of efficiently detecting the defect of the linear electrode by using the above-mentioned basic principle will be described. The present invention was originally conceived for the purpose of detecting defects in a large number of linear electrodes formed on a substrate used in a device such as a plasma display device, a liquid crystal display device, and an image sensor. Therefore, in practice, it is preferable to configure a detection device that can detect a large number of linear electrodes formed on the substrate. The specific detection device described below is a device suitable for performing detection on such a large number of linear electrodes.

Here, for convenience of explanation, a detection target substrate 10 as shown in FIG. 6 is considered. The detection target substrate 10 is one in which five linear electrodes E1 to E5 are formed on an insulating support substrate 11 (for example, a glass substrate). All of these linear electrodes E1 to E5 extend in the lateral direction of the drawing and are arranged at a predetermined interval so as to be parallel to each other. A linear electrode formed on a substrate for an actual plasma display device has, for example, a width of 1
It has a very elongated shape of 00 μm and a length of 1 m, and several hundred of these are arranged in parallel with an average pitch of about 0.65 mm. However, in the drawings of the present application, ignoring the actual dimensional ratio, the five linear electrodes E1 to E5 are ignored.
The following description will be given for a simple model in which only the

Now, the detection target substrate 10 as shown in FIG.
In order to perform the defect detection of the probe substrate 20, a probe substrate 20 as shown in FIG. 7 is prepared. This probe substrate 20 is
On an insulating support substrate 21 (for example, a glass substrate),
The four elongated probe electrodes P1 to P4 and the shield wire S
Are formed and the upper surface thereof is further covered with an insulating film. The shield wire S is a conductive wire arranged in the gap between the probe electrodes P1 to P4 and is for improving the detection accuracy. That is, the actual probe electrodes P1 to P
Since 4 is a very long and narrow electrode having a width of 500 μm and a length of 50 to 100 cm and arranged at a pitch of about 1.0 mm, it will function as an antenna. When functioning as an antenna in this way, signal components due to radio waves from the external world are mixed in and cause detection accuracy to deteriorate. Therefore, the shield line S is provided to reduce the reception of disturbance as much as possible. As will be described later, this shield line S is grounded at the time of detection.

FIG. 8 is a sectional view of the detection target substrate 10 shown in FIG. 6 taken along the section line 8-8. Support substrate 11
The state where the linear electrode E3 to be detected is formed is clearly shown above. On the other hand, FIG. 9 is a cross-sectional view of the probe substrate 20 shown in FIG. 7 taken along the section line 9-9. The structure in which the probe electrodes P1 to P4 are formed on the support substrate 21 and covered with the insulating film 22 is clearly shown. As the supporting substrate 21, any material may be used as long as it is an insulating substrate that can function as a supporting substrate so that the entire probe substrate 20 does not easily bend or warp. I don't care. Further, the insulating film 22 may be made of any material as long as it has a sufficient insulating property. However, since the insulating film 22 functions as a dielectric that constitutes a capacitive element in a detection process described later, it is preferable to use a material having a dielectric constant as high as possible in order to improve detection sensitivity.
Specifically, if a glass substrate is used as the supporting substrate 21, a pattern made of copper or aluminum is used as the probe electrodes P1 to P4, and a silicon oxide film or the like is used as the insulating film 22, a general semiconductor manufacturing is performed. The probe substrate 20 can be prepared depending on the process. Alternatively, polyimide may be used as the support substrate 21 and the insulating film 22, and a copper printed wiring layer may be used as the probe electrodes P1 to P4.

At the time of detection, the probe substrate 20 thus prepared is turned upside down and is stacked on the detection target substrate 10. At this time, the arrangement direction of the linear electrodes E1 to E5 to be detected and the arrangement direction of the probe electrodes P1 to P4 in the probe substrate 20 are set to be orthogonal to each other. FIG. 10 is a cross-sectional view showing a state in which the probe substrate 20 is stacked on the detection target substrate 10. As shown in FIG.
The linear electrodes E1 to E5 all extend in the horizontal direction, and as shown in FIG. 7, all the probe electrodes P1 to P4 extend in the vertical direction. Pattern is formed. Then, a capacitive element is formed at each intersection position. For example, in the cross-sectional view shown in FIG. 10, the capacitive element is formed at the intersections of the linear electrode E3 and the probe electrodes P1, P2, P3 and P4.

FIG. 11 is a perspective view showing the overall construction of this detection apparatus. The probe substrate 20 is provided on the detection target substrate 10.
The point where is overlapped is as described above. In addition to this, the present detection device includes components such as a voltage supply selection circuit 40, a voltage detection selection circuit 50, a detection circuit 100, an AC power supply G, a buffer 3, and an inversion buffer 4.
The voltage supply selection circuit 40 selects a pair of probe electrodes from the probe electrodes P1 to P4, supplies the alternating voltage from the buffer 3 to one of the selected probe electrodes, and the inverting buffer to the other. 4 is a circuit having a function of supplying an AC voltage from 4. The voltage detection selection circuit 50 selects one linear electrode from the linear electrodes E1 to E5, and detects one end of the selected linear electrode from the detection circuit 10
It is a circuit having a function of connecting to 0. Detection circuit 100
Has a function of detecting the presence / absence of a defect based on the voltage fluctuation induced at one end of the connected linear electrode. The voltage supply selection circuit 40 and the voltage detection selection circuit 50
And for the detailed configuration inside the detection circuit 100,
The circuit configuration will be described below.

<Circuit Configuration of This Detection Device> Next, the circuit configuration of the detection device having the above-described configuration will be described. FIG. 12 is a circuit diagram showing only the portion related to the electrical operation of the above-described detection device. The detection target substrate 10 includes five linear electrodes E1 to E5.
And four probe electrodes P1 to P4 and a shield line S are shown for the probe substrate 20. Linear electrodes E1 to E5 and probe electrodes P1 to P4
And are placed in a positional relationship where they cross over each other,
As described above, the capacitive element is formed at each intersection (in this example, 4 × 5 = 20 intersections). The shielded wire S is grounded, and the probe electrodes P1 to P4 function as an antenna to fulfill the function of preventing disturbance from being mixed into the detection result. Further, one ends of the probe electrodes P1 to P4 are grounded by the terminating resistors R1 to R4. As described above, grounding via these terminating resistors is not always necessary in principle, but it is preferable to provide it in practice for stable detection. These terminating resistors may be provided in advance on the probe substrate 20 or may be connected when performing detection.

A selection circuit 40 for voltage supply is connected to the lower ends of the probe electrodes P1 to P4. In this embodiment, the voltage supply selection circuit 40 is composed of eight sets of analog switches (or relays).
This analog switch can switch whether the lower ends of the probe electrodes P1 to P4 are connected to the output terminal of the buffer 3, the output terminal of the inverting buffer 4, or neither. . That is,
In FIG. 12, among the analog switches shown in the upper and lower two columns in the voltage supply selection circuit 40, the four switches shown on the upper side are selected.
When the pair of analog switches is turned on, the lower ends of the probe electrodes P1 to P4 are connected to the output of the buffer 3. When the four sets of analog switches shown on the lower side are turned on, the lower ends of the probe electrodes P1 to P4 are turned on. Will be connected to the output of the inverting buffer 4. The AC voltage from the AC power supply G is applied to the input terminals of the buffer 3 and the inverting buffer 4, and the buffer 3 and the inverting buffer 4 output AC voltages having the same frequency and the same amplitude but opposite phases.

On the other hand, at the left end of each of the linear electrodes E1 to E5,
The voltage detection selection circuit 50 is connected. In this embodiment, the voltage detection selection circuit 50 is composed of 10 sets of analog switches (or may be relays). This analog switch can switch whether the right end of each of the linear electrodes E1 to E5 is grounded or connected to the input terminal of the detection circuit 100. That is, in FIG. 12, among the analog switches shown in the left and right two columns in the voltage detection selection circuit 50, when 5 sets of analog switches shown on the left side are turned on, the left ends of the linear electrodes E1 to E5 are moved. When the five analog switches connected to the input terminals of the detection circuit 100 and shown on the right side are turned on, the left ends of the linear electrodes E1 to E5 are grounded.

The detection circuit 100 is a circuit for performing defect detection processing based on the voltage fluctuation induced at the left end of the linear electrode selected by the voltage detection selection circuit 50 in this way. FIG. 13 is a diagram showing a switching state of each analog switch in the circuit shown in FIG. 12 when disconnection detection of a specific detection target section of the five linear electrodes E1 to E5 is performed. Here, the state of the analog switch is shown in the case where the hatched portion in the drawing (the portion sandwiched between the probe electrodes P2 and P3 on the linear electrode E3) is selected as the detection target section. That is, among the eight sets of analog switches forming the voltage supply selection circuit 40, if the switches indicated by black circles in FIG. 13 are turned on and the other switches are turned off, the lower end of the probe electrode P2 is turned on. Is applied with the AC voltage from the buffer 3, and the AC voltage from the inversion buffer 4 is applied to the lower end of the probe electrode P3. On the other hand, among the 10 sets of analog switches forming the voltage detection selection circuit 50, if the switches indicated by black circles in FIG. 13 are turned on and the other switches are turned off, the linear electrode E3 is turned off. Only the left end is connected to the detection circuit 100, and the left ends of the remaining linear electrodes E1, E2, E4, E5 are grounded. Therefore, the voltage fluctuation induced at the left end of the linear electrode E3 is input to the detection circuit 100.

By the way, it can be understood that the detection system shown as the basic principle in FIG. 1 can be applied as it is by switching the respective analog switches constituting the voltage supply selection circuit 40 and the voltage detection selection circuit 50 as described above. .
That is, the pair of probe electrodes P in the example of FIG.
Reference numerals 2 and P3 correspond to the pair of probe electrodes 1 and 2 in FIG. 1, and alternating voltages having the same frequency and the same amplitude but opposite phases are applied to the probe electrodes 1 and 2. Further, the linear electrode E3 in the example of FIG. 13 corresponds to the detection target electrode E in FIG.
The disconnection is detected by the voltage fluctuation induced at the left end. That is, if voltage fluctuations above a predetermined level can be observed, it can be recognized that there is a disconnection in the detection target section hatched in the figure, and if voltage fluctuations cannot be observed, it is recognized that there is no disconnection. can do. This is the detection principle of this detection device.

The detection circuit 100 is a circuit for efficiently detecting such disconnection, and an example thereof is shown in FIG. In the detection circuit 100 shown in FIG. 14, the output line from the voltage detection selection circuit 50 (the left end of any one of the selected linear electrodes) is connected to the input buffer 60 and the resistance element R0 is connected. Grounded through. On the other hand, the AC signal generated by the AC power supply G is also input into the detection circuit 100. That is, this AC signal is delayed by a predetermined delay time by the phase delay device 61 and given to the switch drivers 62 and 63.

The output of the input buffer 60 is the bandpass filter 6
4 to a pair of analog switches 65 and 66. The polarity of the signal supplied to the analog switch 65 is inverted by the inversion buffer 67, and the signal supplied to the analog switch 66 passes through the buffer 68 and is supplied to the adder 69 with the same polarity. Adder 6
The signal added by 9 is given to the amplifier 71 through the low pass filter 70, and the signal amplified by the amplifier 71 is output as a digital signal by the A / D converter 72. This digital signal is given to the processor 73, and the processor 73 displays the detection result on the display unit 74 based on the value of the given digital signal.

The switch driver 62 turns on the analog switch 66 when the given AC signal takes a positive half cycle, and turns it off when it takes a negative half cycle. On the other hand, the switch driver 63 turns off the analog switch 65 when the given AC signal takes a positive half cycle, and turns it on when it takes a negative half cycle. Therefore,
The analog switches 65 and 66 are alternately turned on every half cycle of the AC signal generated by the AC power supply G. Here, regarding the delay time by the phase delay device 61, the AC signal generated by the AC power supply G is transmitted from the probe electrodes P1 to P4 to the linear electrodes E1 to E5 via capacitive coupling, and further, the voltage detection selection circuit. It is set to be equal to the delay time required to be transmitted to the analog switches 65 and 66 through the 50, the input buffer 60, and the bandpass filter 64. Therefore, the AC signals transmitted to the analog switches 65 and 66 and the AC signals supplied to the switch drivers 62 and 63 are in phase with each other. After all, the combination of the switch driver 62 and the analog switch 66 constitutes a filter that extracts and outputs only the positive component of the AC voltage output from the input buffer 60 based on the signal from the phase delay device 61. Therefore, the combination of the switch driver 63 and the analog switch 65 is
Based on the signal from the phase delay device 61, the input buffer 6
Only the negative component of the AC voltage output by 0 is extracted,
A filter which inverts this and outputs it is constructed.

<Circuit Operation of This Detection Device> Next, the detection operation using the detection device having the above-mentioned configuration will be described with reference to the circuit diagrams of FIGS. 13 and 14. Here, of the five linear electrodes E1 to E5, the third linear electrode E3 is selected as a detection target, and moreover, the central portion of the linear electrode E3 shown in FIG. A case will be described in which detection is performed with a portion sandwiched between the electrodes P2 and P3) as a detection target section. That is, the following detection operation is an operation of checking whether or not there is a disconnection in the hatched detection target section.

When detecting such a detection target section, it is sufficient to switch each analog switch to a state as shown in FIG. 13 (switches indicated by black circles are ON, and other switches are OFF). Already mentioned. Now, in such a state, as shown in FIG.
Consider a case where an AC voltage having a waveform as shown in is supplied.
At this time, theoretically, when there is no disconnection point in the detection target section as in the models shown in FIGS. 2 to 4,
Since no voltage fluctuation occurs at the left end of the linear electrode E3, the voltage input to the detection circuit 100 becomes zero. However, actually, as shown in FIG. 16, various noise components appear as a voltage. On the other hand, in the case where there is a disconnection point in the detection target section as in the model shown in FIG. 5, theoretically, the voltage fluctuation corresponding to the AC signal generated by the AC power supply G is somewhat small. With the phase difference (as described above, there is a time delay until the AC signal is transmitted to the detection circuit 100), the detection circuit 100 is kept as it is.
However, in reality, a noise component is also mixed in this voltage fluctuation as shown in FIG. Therefore, in practice, when the voltage fluctuation as shown in FIG. 16 is observed, the detection result “no disconnection in the detection target section” is obtained, and the voltage fluctuation as shown in FIG. 17 is observed. If there is a disconnection, there is a disconnection in the detection target section.
It is necessary to obtain the detection result of The detection circuit 100 is a circuit for obtaining such a correct detection result.

First, the signal output from the input buffer 60 is passed through a bandpass filter 64 to remove noise components. In this embodiment, the AC power source G is 1 MHz.
Since it uses a device that generates an AC voltage with a frequency of
As the bandpass filter 64, a filter that passes this 1 MHz frequency band is prepared. By passing through the bandpass filter 64, only the component shown as a sine wave can be extracted from the waveform shown in FIG. The signal thus passed through the band pass filter 64 passes through a filter constituted by analog switches 65 and 66 and buffers 67 and 68. As described above, the analog switches 65 and 66 delay the AC signal generated by the AC power supply G so that the phases are matched by the phase delay device 61, and are turned ON / OFF in synchronization with the delay signal. become. Therefore, a positive half cycle of the signal that has passed through the band-pass filter 64 is supplied from the analog switch 66 to the adder 69 through the buffer 68, and a negative half cycle is supplied from the analog switch 65 to the inverting buffer 67.
It is supplied to the adder 69 after being inverted through. After all, in the adder 69, the positive half-cycle portion and the negative half-cycle portion are summed as absolute values, and the output of the adder 69 becomes a signal obtained by rectifying the sine wave signal. This signal is smoothed by passing through the low-pass filter 70, amplified by the amplifier 71, and converted into a digital signal by the A / D converter 72. After all, when the voltage fluctuation as shown in FIG. 16 is observed, a relatively small digital value is obtained from the A / D converter 72, and the voltage fluctuation as shown in FIG. 17 is observed. In this case, the A / D converter 72
Will give a relatively large digital value.
Therefore, in the processor 73, a predetermined threshold value is set, and when the digital value given from the A / D converter 72 exceeds this threshold value, it is determined that there is a disconnection in the current detection target section. The display may be displayed on the display unit 74.

<All Detection Steps for Detection Target> The method for detecting the presence / absence of disconnection in the specific detection target section shown by hatching in FIG. 13 has been described above. The detection device of this embodiment is characterized in that the same detection can be repeated by a simple operation for all the sections of all the linear electrodes E1 to E5 formed on the substrate that is the detection target. That is, in FIG. 13, if the combination of ON / OFF of the analog switches by the voltage supply selection circuit 40 is changed, it is possible to immediately detect other sections. For example, by switching the probe electrode P3 to the output of the buffer 3 and the probe electrode P4 to the output of the inverting buffer 4, the section immediately to the right of the hatched section (probe electrodes P3 and P4 It is possible to obtain the detection result for the area sandwiched by and. In this embodiment, for convenience of description, a simple model using only four probe electrodes P1 to P4 is shown, but in reality, a larger number of probe electrodes P1 to Pn are used.
Are arranged, and by selecting a pair of probe electrodes from these n probe electrodes and connecting them to the buffer 3 and the inversion buffer 4, detection is individually performed on the whole section of the linear electrode. It can be carried out. When the disconnection is detected, the disconnection position (the detection target section at that time) can be immediately recognized.

The following several methods are conceivable as the detection method over the entire section when n probe electrodes are used. In the following description, a section sandwiched between the Xth probe electrode Px and the Yth probe electrode Py is referred to as a section Lx, y.

Method: First, the probe electrodes P1 and P2 are selected to detect the sections L1 and L2, and subsequently, the probe electrodes P2 and P3 are selected and the sections L2 and 3 are selected.
About the probe electrodes P3 and P4
Is selected to detect the sections L3 and L4,
Finally, the probe electrodes P (n-1) and Pn are selected to detect the sections L (n-1) and n, and the detection is sequentially performed for each section. According to this method, for example, if a disconnection is detected when the probe electrodes Pi, Pj are selected and the detection is performed for the section Li, j, it is recognized that the disconnection point exists in the section Li, j. be able to.

Method: In this method, the first probe electrode P1 is always selected as one probe electrode. That is, first, the probe electrodes P1 and P2 are selected to detect the sections L1 and L2, subsequently, the probe electrodes P1 and P3 are selected to detect the sections L1 and 3, and then, The probe electrodes P1 and P4 are selected to detect the sections L1 and L4, ...
The probe electrodes P1 and Pn are selected to detect the sections L1 and n, and the detection is sequentially performed while gradually widening the width of the sections. According to this method, for example, the probe electrodes P1 and Pi are selected and the section L
Although no disconnection was observed when the detection of 1, i was performed, the probe electrodes P1, P (i +
When disconnection is detected when 1) is selected and the detection is performed for the section L1, (i + 1), it can be recognized that the disconnection point exists in the section Li, (i + 1). In the method, there is a possibility that the so-called boundary portion of the section immediately below the probe electrode may not be accurately detected, but this method has an advantage that such a boundary portion can be correctly detected.

Method: In this method, overlapping detection is performed while shifting the intervals by half pitch. That is, first, the probe electrodes P1 and P3 are selected, and the sections L1 and 3 are selected.
Of the probe electrodes P2, P
4 is selected to perform detection for the sections L2 and 4, then probe electrodes P3 and P5 are selected to select sections L3 and 5
Is selected, the probe electrodes P4 and P6 are selected, the sections L4 and 6 are detected, and so on. After all, section L1,3, section L
The detection is performed by overlapping the second and fourth sections, the sections L3 and 5, and the sections L4 and 6 by a half pitch, and again, there is an advantage that the boundary portion of the sections can be correctly detected.

The method for detecting disconnection over the entire length of one linear electrode has been described above. In the detection apparatus of this embodiment, the same detection is repeated for all linear electrodes E1 to E5 by a simple operation. It can be carried out. That is, FIG.
In 3, the detection of other linear electrodes can be immediately performed by changing the ON / OFF combination of the analog switches by the voltage detection selection circuit 50. Specifically, the analog switch may be switched so that the left end of the linear electrode selected as the detection target is connected to the detection circuit 100 and the other linear electrodes are grounded.

An analog switch (or a relay) of the voltage supply selection circuit 40 and the voltage detection selection circuit 50.
The switching operation can be easily performed manually, but can also be automatically switched by, for example, a control signal from the processor 73. Therefore,
If a predetermined detection procedure program is prepared in the processor 73, it is possible to automate all the detection steps according to this program.

When the number of linear electrodes or the number of probe electrodes increases, the number of analog switches or relays provided in the voltage supply selection circuit 40 or the voltage detection selection circuit 50 must also increase, and the cost increases accordingly. Get higher Therefore, if there is a demand to reduce the cost even if the operability of the detection work is sacrificed, the number of switches required for the voltage supply selection circuit 40 and the voltage detection selection circuit 50 is (1 / m). It is also possible to employ a method in which only the number of switches are provided and the voltage supply selection circuit 40 and the voltage detection selection circuit 50 are moved m times when performing the detection work. For example, when performing detection on the detection target substrate 10 on which 1000 linear electrodes are formed, the voltage detection selection circuit 50 has a function of selecting one from 1000 and supplying AC power. It is necessary to prepare a circuit having the above, and for that purpose, 2000 sets of switches are required. It takes a considerable cost to make such a large-sized voltage detection selection circuit 50. In such a case, for example, the detection can be performed even if the voltage detection selection circuit 50 which can handle only 100 linear electrodes is prepared. That is, this voltage detection selection circuit 50 is set to 100
The voltage detecting selection circuit 50 is connected to the 1st to 100th linear electrodes among the 0 linear electrodes and sequentially detected from the 1st to 100th linear electrodes. , The voltage detection selection circuit 5 is sequentially detected from the 101st to the 200th, and so on.
If 0 is moved 10 times, detection is possible for all 1000 linear electrodes.

<When there are a plurality of disconnection points> In the above embodiment, the description has been made assuming that there is one disconnection point in the linear electrode, but the defect detection method according to the present invention is It is possible to detect even when a plurality of points on the linear electrode of the book are broken.

This will be described with reference to the equivalent circuit of FIG.
This equivalent circuit is a circuit in the case where disconnection occurs at two positions on the detection target electrode E, that is, predetermined positions x1 and x3. Here, the disconnection detection at the position x1 (the equivalent circuit for performing such detection is that the point g in FIG.
To the left of the point h to the right of the position x1, respectively. It can be easily understood that the above) can be performed according to the principle described in the above embodiment. This is because the other disconnection position x3 is on the right end b side rather than the left end a side where the voltage fluctuation is detected, and therefore has no effect on the detection including the position x1 in the detection target section. However, the situation is slightly different when the detection including the position x3 in the detection target section is performed. That is, with respect to the disconnection at the position x3, the other disconnection position x3 is located on the left end a side where the voltage fluctuation is detected, and therefore the detection system should be affected in some way. Certainly, if the wire is broken at the position x1, the current stops flowing from the point g to the point a.
However, even in such a state, the disconnection at the position x3 can still be detected.

This is for the following reason. Now, Figure 1
As shown in FIG. 8, consider the moment when a negative charge is induced at the point g and a positive charge is induced at the point h. Here, since the position x3 is broken, these charges are not canceled by each other.
By the way, since the section from the position x3 to the position x1 is conductive, the negative charge is induced at the point g, which means that the negative charge is generated also in the portion immediately to the right of the position x1. It will be. Here, considering the disconnection state at the position x1, there is a conductor on the right side of the position x1 and a conductor on the left side of the position x1. Both conductors are arranged to face each other. I understand that. In other words, the conductor immediately to the right of position x1 and the position x
The conductor immediately to the left of 1 is capacitively coupled. Therefore, if a negative charge is generated in the portion immediately to the right of the position x1, this capacitive coupling will induce a positive charge in the portion immediately to the left of the position x1. After all,
The voltage fluctuation induced at the point g is transmitted to the amplifier 5 via the capacitive coupling in the disconnection portion at the position x1.

Although the capacitive coupling of the disconnection portion is weaker than that of a general capacitive element, the potential fluctuation at the position g can still be transmitted to the amplifier 5 and detected. Therefore, with the detection method according to the present invention, even if disconnection occurs at a plurality of locations on a single linear electrode, this can be detected.

Although the present invention has been described above based on the illustrated embodiment, the present invention is not limited to this embodiment and can be implemented in various modes other than this. For example, in the above-described embodiment, as the probe substrate 20, as shown in FIG. 9, the one in which the insulating film 22 is formed on the probe electrodes P1 to P4 is used.
2 is not always necessary. As shown in FIG. 10, when the detection target substrate 10 and the probe substrate 20 are opposed to each other, the probe electrodes P1 to P4 are linear electrodes E1 to E.
The defect detection according to the present invention is possible if it is possible to prevent it from coming into contact with the insulating film 5. Therefore, the insulating film 22 need not be formed by inserting some spacer that substitutes for the insulating film 22. Therefore, the detection target substrate 10 itself shown in FIG. 6 can be used instead of the probe substrate 20 shown in FIG. That is, FIG.
If two sets of detection target substrates 10 having a structure as shown in (1) are prepared and one of them is made to face each other while being rotated by 90 °, one of the linear electrodes can be used as a substitute for the probe electrode. is there.

In the substrate to be detected in the above embodiment,
Although the linear electrodes are exposed on the substrate, some substrates for plasma display devices have a structure in which the linear electrodes are covered with an insulating film. In such a case where the detection target substrate itself is covered with the insulating film, the insulating film 22 on the probe substrate 20 side is not always necessary. conventionally,
As described above, it was very difficult to detect a defect in the linear electrode covered with the insulating film because the probe cannot be brought into contact with the defect. However, if the detection method according to the present invention is used, the defect can be detected without any problem. . Further, the present invention can detect defects in the electrode substrate after the cell barrier is formed.

As described above, the detection is performed by properly grounding the respective parts of the linear electrode and the probe electrode according to the present invention, but this does not necessarily have to be a ground level (so-called ground), and a predetermined reference If it can be fixed at a voltage, it may be connected to a predetermined constant voltage source instead of being grounded.

[0058]

As described above, according to the defect detecting method for a linear electrode of the present invention, a pair of probe electrodes are arranged on the linear electrode and capacitively coupled, and the capacitive coupling causes the linear electrode side. Since the defect on the linear electrode is detected by observing the voltage fluctuation, the defect can be efficiently detected.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the basic principle of a defect detection method for a linear electrode according to the present invention.

FIG. 2 is an equivalent circuit diagram of the detection system shown in FIG.

FIG. 3 is an equivalent circuit diagram in the detection system shown in FIG. 1 when there is a disconnection defect between points ag.

FIG. 4 is an equivalent circuit diagram in the case where there is a disconnection defect between points hb in the detection system shown in FIG.

5 is an equivalent circuit diagram in the detection system shown in FIG. 1 when there is a disconnection defect between points gh.

FIG. 6 is a plan view showing an example of a detection target substrate 10 for implementing the defect detection method according to the present invention.

FIG. 7 is a plan view showing an example of a probe substrate 20 which is a component of the defect detection apparatus according to the embodiment of the present invention.

8 is a cross-sectional view of the detection target substrate 10 shown in FIG. 6 taken along section line 8-8.

9 is a cross-sectional view of the probe substrate 20 shown in FIG. 7 taken along section line 9-9.

10 is a cross-sectional view showing a state in which the probe substrate 20 shown in FIG. 9 is superposed on the detection target substrate 10 shown in FIG.

FIG. 11 is a perspective view showing the overall configuration of a defect detection apparatus according to an embodiment of the present invention.

FIG. 12 is a circuit diagram showing only a portion related to an electrical operation in the defect detection device shown in FIG.

13 is a circuit diagram showing an operation of detecting a disconnection defect using the circuit shown in FIG.

14 is a circuit diagram showing an internal configuration of a detection circuit 100 shown in FIGS. 12 and 13. FIG.

15 is a graph showing an example of an AC voltage waveform generated by an AC power supply G in the detection circuit shown in FIGS. 12 and 13.

16 is a graph showing an example of a voltage fluctuation waveform observed in the detection circuit 100 in the detection circuit shown in FIGS. 12 and 13 when no disconnection occurs.

FIG. 17 is a graph showing an example of a voltage fluctuation waveform observed in the detection circuit 100 when a disconnection occurs in the detection circuits shown in FIGS. 12 and 13.

FIG. 18 is an equivalent circuit diagram explaining that the detection method according to the present invention enables detection even when disconnection occurs at a plurality of points on one linear electrode.

[Explanation of symbols]

 1, 2 ... Probe electrode 3 ... Buffer 4 ... Inversion buffer 5 ... Amplifier 10 ... Detection target substrate 11 ... Support substrate 20 ... Probe substrate 21 ... Support substrate 22 ... Insulating film 40 ... Voltage supply selection circuit 50 ... Voltage detection selection Circuit 60 ... Input buffer 61 ... Phase delay device 62, 63 ... Switch driver 64 ... Band filter 65, 66 ... Analog switch 67 ... Inversion buffer 68 ... Buffer 69 ... Adder 70 ... Low-pass filter 71 ... Amplifier 72 ... A / D Converter 73 ... Processor 74 ... Display part 100 ... Detection circuit C1, C2 ... Capacitance element E ... Detection target electrode E1-E5 ... Linear electrode G ... AC power supply P1-P4 ... Probe electrode R0 ... Resistance element R1-R4 ... Termination Resistance S ... Shielded wire

Front Page Continuation (72) Inventor Nao Tanabe 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo Dai Nippon Printing Co., Ltd.

Claims (6)

[Claims] 1. A method for detecting a defect in a linear electrode extending in a predetermined direction, wherein a first probe electrode and a second probe electrode are provided at positions on both sides of a detection target section of the linear electrode. A first AC voltage and a second AC voltage having a frequency and an amplitude equal to each other and having phases inverted from each other are prepared by arranging them with a predetermined distance from each of the linear electrodes. When the first AC voltage is applied to the probe electrode and the second AC voltage is applied to the second probe electrode, the same frequency as the AC voltage induced at one end of the linear electrode is applied. A method for detecting a defect of a linear electrode, which comprises measuring a voltage fluctuation and detecting the presence or absence of a defect in the detection target section based on the amplitude of the voltage fluctuation. 2. The detection method according to claim 1, wherein the first probe electrode and the second probe electrode are:
Each elongated electrode is used, one end of each probe electrode is fixed to a predetermined reference potential via a terminating resistor, an AC voltage is applied to the other end of each probe electrode, and the voltage fluctuation detection end of the linear electrode is a resistance element. A defect detection method for a linear electrode, which is characterized in that the voltage fluctuation detection end is connected to an amplifier via the circuit, and the presence or absence of a defect is detected based on the output voltage of the amplifier. 3. A method for detecting defects in a plurality of linear electrodes extending along a first direction in a first plane and arranged substantially parallel to each other, the method comprising: In the second plane parallel to
A plurality of elongated probe electrodes that extend along a second direction that is substantially perpendicular to the first direction and that are arranged substantially parallel to each other face the plurality of linear electrodes, and have equal frequencies and amplitudes; A first AC voltage and a second AC voltage having a phase-inverted relationship with each other are prepared, one of the plurality of linear electrodes is set as a detection target, and one linear line that is the detection target is set. One of the pair of probe electrodes located on both sides of the detection target section of the electrode is defined as a first probe electrode and the other is defined as a second probe electrode, and the first AC voltage is applied to the first probe electrode. In addition, when the second AC voltage is applied to the second probe electrode, a voltage fluctuation of the same frequency as the AC voltage induced at one end of the linear electrode to be detected is measured, Voltage Defect detection method of linear electrodes and detecting the presence or absence of a defect in the detection target section based on the amplitude of the dynamic. 4. The detection method according to claim 3, wherein one end of each probe electrode is fixed to a predetermined reference potential via a terminating resistor, and the other end of each of the first probe electrode and the second probe electrode is fixed. AC voltage is applied, the voltage fluctuation detection end of the linear electrode to be detected is fixed to a predetermined reference potential via a resistance element, the voltage fluctuation detection end is connected to an amplifier, and based on the output voltage of this amplifier. A method for detecting a defect in a linear electrode, characterized in that the presence or absence of a defect is detected. 5. An apparatus for detecting defects in a plurality of linear electrodes extending along a predetermined direction in a predetermined plane and arranged substantially parallel to each other, comprising a flat support substrate, A probe substrate having a plurality of elongated probe electrodes extending along a predetermined direction on the support substrate and arranged substantially parallel to each other, and an insulating film formed so as to cover the probe electrodes; A voltage supply circuit that supplies a first AC voltage and a second AC voltage that are equal and have mutually inverted phases, and a pair of probe electrodes selected from the plurality of probe electrodes, and the selected probe electrodes A voltage supply selection circuit that supplies the first AC voltage to one side and the second AC voltage to the other side; and one linear electrode from the plurality of linear electrodes. A voltage detection selection circuit for extracting a voltage fluctuation induced at one end of the selected linear electrode, and between the selected pair of probe electrodes in the selected linear electrode based on the voltage fluctuation. A detection circuit for detecting the presence / absence of a defect in a portion corresponding to, and a defect detecting device for a linear electrode, comprising: 6. The detection device according to claim 5, wherein a phase delayer that delays the phase of the AC signal obtained from the voltage supply circuit by a predetermined delay time and a voltage fluctuation extracted from the voltage detection selection circuit are included. A first filter for extracting and outputting only a positive component based on the signal from the phase delay device, and a voltage fluctuation extracted from the voltage detection selection circuit A second filter for extracting only the negative component based on the output and inverting and outputting the negative component; and an adder for adding the output of the first filter and the output of the second filter. A defect detecting device for a linear electrode, which constitutes a detection circuit and detects the presence or absence of a defect based on the output of the adder.