JP2879065B2 - Method and apparatus for detecting short circuit between electrodes - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for detecting a short circuit between a plurality of electrodes arranged in a band on a substrate used for a liquid crystal display device or the like.

[Prior Art] In a manufacturing process of forming a strip-shaped electrode provided on a substrate such as a liquid crystal display element, a short circuit often occurs between adjacent electrodes. May be required. As a method for detecting a short circuit in such a case, a visual appearance inspection using a microscope, that is, a so-called visual method is generally performed. However, the visual method has problems such as fatigue of the operator, occurrence of oversight, possibility of contamination of the substrate, and excessive time required for detection as the electrode pattern becomes increasingly fine in recent years. It is not preferable to use it in a manufacturing process of a display element or the like on the premise of production.

In order to solve such a problem, Japanese Patent Application Laid-Open No. Sho 62-66152
Japanese Patent Application Laid-Open No. HEI 9-163702 proposes a so-called conduction method in which two probes are brought into contact with two electrodes from which a short circuit is to be detected, and the presence or absence of a short circuit between the two electrodes is detected.

[Problems to be Solved by the Invention] However, even when such a conduction method is employed, it is only known that a short circuit has occurred between two specific electrodes, and the position is determined by the position of the electrodes. It is not clear which part of the electrode is short-circuited. Eventually, the electrode where the short-circuit was detected was visually observed with a microscope or the like, and the short-circuited part was detected and repaired. Therefore, although it is slightly improved as compared with the case where only the above-mentioned visual method is used, it is still inconvenient in that much labor is required.

In particular, when there is a colored filter under the electrode, a minute short circuit is difficult to see, and when a short circuit occurs due to the presence of foreign matter between the electrodes, it is often impossible to visually discriminate.

Means for Solving the Problems The present invention has been made to solve the problems, and detects a short circuit between adjacent electrodes in at least one substrate having a plurality of strip-shaped electrodes. A method comprising: contacting each of two ends of a first electrode selected from the electrodes with two probes;
One end or both ends of the second electrode for which the presence or absence of a short circuit with the electrode is to be detected, and bringing the probe into contact with a position close to the probe in contact with the first electrode; By estimating or measuring the resistance values between two probes of three types selected from the above probes, which are linearly independent from each other, the first electrode and the second electrode Detecting the presence or absence and location of a short circuit between electrodes, and a device for detecting a short circuit between adjacent electrodes in at least one substrate having a plurality of strip-shaped electrodes And two probes respectively contacting both ends of a first electrode selected from the electrodes, and one end of a second electrode to be detected whether there is a short circuit with the first electrode. Part or both ends, the first electrode A probe to be brought into contact with a position close to the contacting probe, a means for measuring a resistance value between the probes, and whether or not there is a short circuit between the first electrode and the second electrode based on the resistance value. And a computing device for computing and detecting the location. A device for detecting a short circuit between electrodes is provided.

FIG. 1 is a principle diagram for explaining the basic principle of the present invention. FIG. 2 is a conceptual diagram of an apparatus according to an example of the present invention. In FIG. 2, X ₁ and X ₂ are adjacent electrode patterns for detecting a short circuit therebetween, and P ₁ , P ₂ , P ₃ , and P ₄ are electrodes X ₁ ,
A position to make a probe for detection of shorts X _2, X _1, X ₂
And P ₁ , P ₃ and P ₂ , P ₄ are close to each other. Electrodes X _1, X ₂ on the probe P _1, between P _2, or P _3, the distance and the resistance between P ₄ are respectively close to the P _1, P ₃ and P _2, P _4, X ₁ and X ₂ can be regarded as approximately the same. If the distance between the probes on the same electrode is L and the resistance between the probes on the same electrode is R (see FIG. ₁ ), the ratio of the distance between the short-circuit position and the reference point (here, P1) to L the When x, distance and resistance to short-circuit point of the reference point P ₁ may be respectively represented xL, and xR.

At this time, assuming that the resistance value of the short-circuit portion is r, the unknown values are x, R, and r. Therefore, if the resistance value between the two probes selected from the above three probes is three. Then, if the values that are linearly independent of each other can be measured, the unknown value x can be known.

Here, the three types of resistance values that are linearly independent from each other refer to a relationship in which two other primary resistances cannot be obtained to obtain another resistance value. For example, if the resistance between the P _j and P _i to the fact that _{R ij, R 14, R 23} , R 12 is
It is not linearly independent because of the relationship R ₂₃ = R ₁₄ .

R ₁₂ , R ₁₃ , R
_{There is a combination of 14} and R ₁₂ , R ₁₃ , R ₂₄ and R ₁₂ , R ₁₃ , R ₂₃ and an arrangement in which they are inverted vertically or horizontally.

To give an example of a specific calculation method, for example, if R ₁₂ , R ₁₄ , and R ₁₃ are known, R ₁₂ = R, so R ₁₄ = R + r ‥‥‥ (1) R ₁₃ = 2 × R + r ‥‥‥ ( From the relationship 2), x = (R ₁₃ −R ₁₄ + R) / 2RR (3)

For R ₁₂ and R ₃₄ , almost all electrodes have the same value (= R)
In many cases, after measuring one electrode, that value may be used as an estimated value.

FIGS. 2 and 3 are conceptual diagrams of an apparatus for realizing the above method.

FIG. 2 shows that a voltage is applied to the electrode by mechanically tracing the non-inspection electrode with a probe in a direction substantially perpendicular to the direction of the electrode band to detect the presence or absence of a short circuit and the location of the short circuit. The number of probes was four.

In this case, for example, by measuring the resistance value between P ₁ and P _2, between P ₁ and P _{4, and} between P ₁ and P ₃ , and performing the above-described predetermined calculation, the presence or absence of a short circuit and the position of the short circuit are determined. Detection is possible. In this case, by measuring the resistance between P _1, P _2, by comparing the resistance of the other of X ₁ Other electrodes, also know at the same time immediately whether disconnection of X _1, also, P _1, P Measure the resistance between ₄ and
If you compare with the same resistance value of other electrodes,
This indicates whether there is a short circuit between X ₁ and X ₂ .

Also, after measuring the resistance between P ₁ and P _{2 and} between P ₁ and P ₄ , switch the voltage application to P ₁ and P ₂ with a circuit so that the resistance between P ₂ and P ₄ can be measured. if, P ₃ is unnecessary.

In addition, as shown in FIG. 3, a contact such as a probe is set up entirely or partially on the end of the electrode to be inspected so that a current flows through each electrode, and is incorporated into an inspection machine for inspecting disconnection and short-circuit. The short-circuit position can be detected simultaneously with the short-circuit inspection.

The method and apparatus for detecting a short circuit between electrodes according to the present invention include:
It is widely effective not only for detecting a short circuit between electrodes of a liquid crystal display element, but also for detecting a short circuit between electrodes arranged in a band.

Further, the above description can be applied not only to the detection of a short circuit between adjacent electrodes, but also to the electrodes that are close to each other and may cause a short circuit, such as electrodes facing each other.

[Example] An example of detection of a short-circuit position on a liquid crystal display element substrate in the case where adjacent electrodes are short-circuited at positions as shown in FIG. 2 will be described. 15 [Omega] / □ position in P _1, P ₂ between the distance (L) 49.625mm display electrode an electrode having a surface resistance which is patterned in a stripe-shaped line width 0.3mm to short than P ₁ in visually (xL)
Was 8.310 mm, the measured values of R, R ₁₃ , and R ₁₄ were 1.968 KΩ, 0.8138 KΩ, and 2.122 KΩ, respectively. Substituting this resistance value into equation (3) It almost coincided with the measured value of XL of 8.310 mm.

[Effects of the Invention] According to the method and the apparatus for detecting a short circuit between electrodes according to the present invention, the position of a short circuit between electrodes arranged adjacent to each other in a strip can be detected simultaneously with the detection of disconnection and short circuit, and the short circuit is repaired. The time required for detecting the short-circuit position can be shortened, and oversight can be eliminated.

Also, based on the data of the short-circuit location obtained in the present invention,
The repair system can be operated by laser beam irradiation. That is, by sending the data obtained by the present apparatus to the repair apparatus controlled by the computer, the trouble of manually searching for the short-circuit point can be omitted, and the time until the correction can be further reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing the basic principle of the present invention, and FIGS. 2 and 3 are conceptual diagrams of the device according to the present invention. L and R are the distances and resistance values between P ₁ and P ₂ or between P ₃ and P ₄ respectively, x is the distance from a reference point (P ₁ or P _{3 in the} figure) to the short circuit, and P ₁ and P The ratio of the distance between ₂ or P ₃ , P ₄ , r is the resistance value of the short-circuit part, P ₁ , P ₂ , P ₃ , P ₄ are contacts such as probes for disconnection / short-circuit inspection, X ₁ , X ₂ is an electrode.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) G09G 3/36 G02F 1/133 G01R 31/00

Claims (2)

(57) [Claims] 1. A method for detecting a short circuit between adjacent electrodes in at least one substrate having a plurality of electrodes arranged in a strip, wherein both ends of a first electrode selected from the electrodes are provided. And one end or both ends of the second electrode to be detected for the presence or absence of a short circuit with the first electrode, the two probes being in contact with the first electrode. The probe is brought into contact with a position close to the probe in question, and the resistance value between two probes selected from the above three probes, which are linearly independent of each other, is estimated or measured. By doing, the first
A method for detecting the presence or absence and location of a short circuit between the first electrode and the second electrode. 2. An apparatus for detecting a short circuit between adjacent electrodes in at least one substrate having a plurality of electrodes arranged in a strip shape, wherein both ends of a first electrode selected from the electrodes are provided. And one end or both ends of the second electrode to be detected whether there is a short circuit between the two probes and the first electrode, and is in contact with the first electrode. A probe that contacts a position close to the probe,
It is characterized by comprising means for measuring the resistance value between the above-mentioned probes, and an arithmetic unit for calculating and detecting the presence / absence and location of a short circuit between the first electrode and the second electrode from the resistance value. Detection device between the electrodes.