TW201317571A - Wiring defect detecting method, wiring defect detecting apparatus, wiring defect detecting program, and wiring defect detecting program recording medium - Google Patents

Abstract

This wiring defect inspecting method for detecting a wiring short-circuited portion on a semiconductor substrate is characterized in performing: a pre-short-circuiting step of short-circuiting between terminals of wiring to be inspected; and a resistance value measuring step of determining, after the pre-short-circuiting step, whether there is the wiring short-circuited portion or not by measuring a resistance value of the wiring to be inspected.

Description

Wiring defect inspection method, wiring defect inspection device, wiring defect inspection program, and wiring defect inspection program recording medium

The present invention relates to a wiring defect inspection method, a wiring defect inspection device, a wiring defect inspection program, and a wiring defect inspection program recording medium, which are suitable for a TFT used in a liquid crystal display or an organic EL (Electroluminescence) display or the like ( Defect detection of wiring formed on a semiconductor substrate such as a thin film transistor or a solar cell panel.

Generally, in the manufacturing process of a liquid crystal panel, a liquid crystal panel is manufactured via a TFT array process, a unit process, a module process, etc. In the TFT array step, a plurality of gate lines functioning as scanning lines of the TFTs are disposed in parallel on the transparent substrate, and a plurality of roots functioning as signal lines are disposed orthogonally to the gate lines. After the electrode is covered with a protective film, a transparent electrode is formed. Thereafter, an array inspection is performed to check whether the electrodes or wiring are short-circuited.

For example, Patent Document 1 discloses a technique relating to infrared inspection for detecting a short-circuit defect of a substrate by an infrared radiation source. Fig. 14 is a view showing the overall configuration of a thin film transistor substrate defect inspection and correction device 300 disclosed in the document. The thin film transistor substrate defect inspection and correction device 300 detects an infrared image of a wiring portion and a short defect portion of a substrate which generates heat due to energization by using a difference image of the inspection target substrate 301 before and after application of a voltage. Switching the applied voltage, detecting position, lens, etc. according to the linear or dot-like heating pattern or the position of the defect, the number of defects, and the like The infrared ray detector 303 or the like detects the heat generating wiring so that the defect position can be specified.

Further, Patent Document 2 discloses a method of detecting a short circuit between a plurality of types of wirings arranged on a substrate by electrical inspection, and performing an infrared inspection to specify a short-circuit position when a short circuit is detected. The electrical inspection measures the resistance by applying a voltage to the wiring. If the resistance value is not infinite, a current flows and it is determined that there is a short circuit. Alternatively, a voltage is applied to the wiring line, and the current value is measured. If the current is not 0, it is determined that there is a short circuit.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. Hei 6-207914 (published on July 26, 1994)

[Patent Document 2] Japanese Laid-Open Patent Publication No. Hei 2-64594 (published on March 5, 1990)

However, in the method of measuring the resistance between the plurality of types of wirings disposed on the substrate and detecting the short circuit between the wirings as disclosed in Patent Document 2, after the resistance measurement is started, the measured value fluctuates until it is stable and converges. This is because the electronic component or the electronic circuit has a stray capacitance which is a capacitance component which is not intended by the designer due to the physical structure.

For example, a general equivalent circuit at the time of resistance measurement is shown in FIG. The stray capacitance is described as equivalent to the charge capacity of the capacitor 312. The resistance value of the resistor 311 is a resistance component connected in parallel with the capacitor 312. resistance The resistance value of 315 is a resistance component connected in series with the capacitor 312. Here, the total value of the resistances of the resistor 311 and the resistor 315 is measured. As a result, electrostatic capacitance occurs in the insulating layer between the wiring or the wiring on the substrate and the wiring, which affects the resistance measurement operation.

Specifically, in FIG. 15, when the switch 313 is closed and the voltage is applied by the power source 314 to start the resistance measurement, the stray capacitance occurs immediately after the switch 313 is closed, so that it is in the form of the capacitor 312 regardless of the resistance value of the resistor 311. The current is transmitted in such a manner that the node 316 at both ends is short-circuited with the node 317. First, a current flows to the capacitor 312, and then a current flows through the capacitor 312 and the resistor 311. When the charging of the capacitor 312 is completed, only a current flows through the resistor 311. This phenomenon is called dielectric absorption, and after the dielectric absorption is converged, the total value of the resistances of the resistor 311 and the resistor 315 can be accurately measured.

Further, there is a case where the capacitor 312 is charged a small amount in advance by resistance measurement or static electricity in the other wiring compartments. Therefore, depending on the amount of charge of the capacitor 312 before the resistance measurement is performed, the time until the dielectric absorption converges occurs. Variation, the case where the total measurement time required for resistance measurement is deviated. If there is a variation in the measurement time, it is necessary to estimate the time until the dielectric absorption converges for a long period of time, or to perform each measurement based on the measurement data of the past and the longest measurement time. Therefore, there is a problem that the inspection time taken is lengthened so that the inspection efficiency is lowered.

The present invention has been made in view of the above problems, and an object thereof is to provide a wiring defect inspection method, a wiring defect inspection device, a wiring defect inspection program, and a wiring defect inspection program recording medium which can detect defects of a semiconductor substrate such as a TFT array substrate. Inhibiting the deviation of the measurement time, thereby The defect is checked correctly and efficiently with the appropriate measurement time.

The wiring defect inspection method according to the present invention is characterized in that it is a method of detecting a short-circuit portion of a wiring in a semiconductor substrate, and performing a pre-shorting step of short-circuiting between terminals of a wiring to be inspected; and measuring a resistance value In the step of measuring the resistance value of the wiring to be inspected after the pre-short circuit step, it is determined whether or not the wiring short-circuit portion is present.

The wiring defect inspection device according to the present invention is characterized in that it detects a short-circuit portion of a wiring in a semiconductor substrate, and includes a pre-short portion that short-circuits between terminals of a wiring to be inspected, and a voltage applying portion that faces the above a voltage applied to the wiring of the inspection target; a resistance measuring unit that measures a resistance value of the wiring; and a control unit that controls the voltage application unit; and determines whether or not the wiring short-circuit portion is formed based on a resistance value measured by the resistance measuring unit .

The wiring defect inspection program according to the present invention is characterized in that the wiring defect inspection device is operated by an operator and the computer functions as each of the above-described mechanisms.

The wiring defect inspection program recording medium of the present invention is characterized in that the wiring defect inspection program described above is recorded.

According to the present invention, when a defect of a semiconductor substrate such as a TFT substrate is detected, variation in measurement time can be suppressed, and defects can be inspected accurately and efficiently with an appropriate measurement time.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals are used to refer to the same or equivalent parts.

<Embodiment 1>

1(a) is a block diagram showing the configuration of the wiring defect inspection device 100 of the present embodiment, and FIG. 1(b) is a perspective view of the mother substrate 1 as a target for performing wiring defect inspection using the wiring defect inspection device 100. Here, as shown in FIG. 1(b), eight liquid crystal panels of P1 to P8 are formed on the mother substrate 1.

The wiring defect inspection apparatus 100 can inspect the defects of the wiring or the like in the plurality of liquid crystal panels 2 formed on the mother substrate 1 shown in FIG. 1(b). Therefore, the wiring defect inspection apparatus 100 includes the probe 3 for conducting the liquid crystal panel 2 and the probe moving mechanism 4 for moving the probe 3 to each of the liquid crystal panels 2. Further, the wiring defect inspection device 100 includes an infrared camera 5 for acquiring an infrared image and a camera moving mechanism 6 for moving the infrared camera 5 on the liquid crystal panel 2. Further, the wiring defect inspection device 100 includes a main control unit 7 that controls the probe moving mechanism 4 and the camera moving mechanism 6.

The probe 3 is connected to a resistance measuring unit 8 for measuring the electric resistance between the wirings of the liquid crystal panel 2, a voltage applying unit 9 for applying a voltage between the wirings of the liquid crystal panel 2, and a short-circuit between the terminals to be measured in advance. The pre-short circuit portion 10 of the switch. The resistance measuring unit 8, the voltage applying unit 9, and the pre-short circuit unit 10 are controlled by the main control unit 7.

Fig. 2 is a perspective view showing the configuration of the wiring defect inspection device 100 of the present embodiment. As shown in FIG. 2, the wiring defect inspection apparatus 100 is configured such that an alignment stage 11 is disposed on the base, and the mother substrate can be placed on the alignment stage 11. 1. The alignment stage 11 on which the mother substrate 1 is placed is positionally adjusted in parallel with the XY coordinate axes of the probe moving mechanism 4 and the camera moving mechanism 6. At this time, the position adjustment of the alignment stage 11 uses an optical camera 12 provided above the alignment stage 11 for confirming the position of the mother substrate 1.

The probe moving mechanism 4 is provided to be slidable on the guide rail 13a disposed on the outer side of the alignment stage 11. Further, guide rails 13b and 13c are provided on the main body side of the probe moving mechanism 4, and mounting portions 14a are provided so as to be movable in the respective coordinate directions of the XYZ along the guide rails 13. The probe 3 corresponding to the liquid crystal panel 2 is mounted on the mounting portion 14a.

The camera moving mechanism 6 is provided to be slidable on the guide rail 13d disposed on the outer side of the probe moving mechanism 4. Further, the main body of the camera moving mechanism 6 is also provided with guide rails 13e and 13f, and the three mounting portions 14b, 14c and 14d are respectively movable along the guide rails 13 in the respective coordinate directions of XYZ.

The infrared camera 5a for macro measurement is mounted on the mounting portion 14c, the infrared camera 5b for microscopic measurement is mounted on the mounting portion 14b, and the optical camera 16 is mounted on the mounting portion 14d.

The infrared camera 5a for macro measurement can be expanded to a depth of 520 × 405 mm for infrared measurement of macroscopic cameras. In order to broaden the field of view, the infrared camera 5a for macro measurement is configured by, for example, combining four infrared cameras. That is, the field of view of the infrared camera for each macro measurement is approximately 1/4 of the size of one liquid crystal panel 2. Further, the infrared camera 5b for microscopic measurement has a small field of view of about 32 × 24 mm, but is an infrared camera capable of microscopic measurement capable of high-resolution photography.

Further, an attachment portion may be added to the camera moving mechanism 6 for mounting Correct the laser irradiation device of the defective part. By mounting the laser irradiation device, it is possible to continuously perform defect correction by irradiating the defective portion with a laser after the position of the specific defect portion.

The probe moving mechanism 4 and the camera moving mechanism 6 are respectively disposed on different guide rails 13a and 13d. Therefore, it is possible to move without interference in the X coordinate direction above the alignment stage 11. Thereby, the infrared cameras 5a and 5b and the optical camera 16 can be moved to the liquid crystal panel 2 with the probe 3 in contact with the liquid crystal panel 2.

FIG. 3(a) is a plan view of one of the plurality of liquid crystal panels 2 formed on the mother substrate 1. As shown in FIG. 3(a), the liquid crystal panel 2 is formed with a pixel portion 17, a peripheral wiring portion 18, and terminal portions 19a to 19d. The pixel portion 17 is formed with a gate line and a source line, and a TFT is formed at each intersection of the gate line and the source line. Wiring for connecting the gate line and the source line to the terminal portions 19a to 19d is formed in the peripheral wiring portion 18.

FIG. 3(b) is a plan view of the probe 3 for conducting electricity with the terminal portions 19a to 19d provided on the liquid crystal panel 2. The probe 3 is formed in a frame shape having a size substantially equal to that of the liquid crystal panel 2 shown in FIG. 3(a), and includes a plurality of probes 21a corresponding to the terminal portions 19a to 19d provided on the liquid crystal panel 2. ~21d. The plurality of probes 21a to 21d can individually connect the probes 21 to the resistance measuring unit 8 and the voltage applying unit 9 shown in Fig. 1(a) via relays (not shown). Therefore, the probe 3 can be selectively connected to a plurality of wires connected to the terminal portions 19a to 19d, or a plurality of wires can be connected in total. Further, the probe 3 is formed into a shape of a frame having substantially the same size as that of the liquid crystal panel 2. Furthermore, as described above, the position adjustment of the mother substrate 1 is performed by using the optical camera 12, The positions of the terminal portions 19a to 19d and the probes 21a to 21d are aligned.

As described above, the wiring defect inspection apparatus 100 of the present embodiment includes the probe 3 and the resistance measuring unit 8 connected to the probe 3. The probe 3 and the liquid crystal panel 2 are electrically connected to each other, and the resistance value of each wiring and the adjacent wiring can be measured. The resistance value between them.

Further, the wiring defect inspection apparatus 100 of the present embodiment includes a probe 3, a voltage application unit 9 connected to the probe 3, and infrared cameras 5a and 5b. Then, a voltage is applied between the wiring or the wiring of the liquid crystal panel 2 via the probe 3, and the heat generated by the current flowing through the defective portion is measured by the infrared cameras 5a and 5b, whereby the position of the defective portion can be specified. Therefore, according to the wiring defect inspection apparatus 100 of the present embodiment, the resistance inspection and the infrared inspection can be performed by using one inspection apparatus.

Fig. 4 is a flowchart showing a wiring defect inspection method using the wiring defect inspection device 100 of the present embodiment. The S in the flowchart indicates each step. As shown in FIG. 4, in the wiring defect inspection method of the present embodiment, the wiring defect inspection is sequentially performed on the plurality of liquid crystal panels 2 formed on the mother substrate 1 by the steps S1 to S10.

First, in step S1, the mother substrate 1 is placed on the alignment stage 11 of the wiring defect inspection apparatus 100, and the position of the substrate is adjusted so as to be parallel to the XY coordinate axis. Then, in step S2, the probe moving mechanism 4 moves the probe 3 to the upper portion of the liquid crystal panel 2 to be inspected, and the probes 21a to 21d are brought into contact with the terminal portions 19a to 19d of the liquid crystal panel 2. Here, in step S3, all the terminals of the wiring to be measured or the wiring are short-circuited. The short circuit treatment refers to being connected to the probes 21a 21d by being closed respectively. Relays (not shown) electrically short the probes. The gate line and the source line formed on the liquid crystal panel 2 are not electrically connected to each other. However, in the short-circuit operation, the wiring or the wiring to be measured is electrically connected.

Usually, a plurality of gate lines functioning as scanning lines are disposed in parallel on the liquid crystal panel, and a plurality of source lines functioning as signal lines are disposed orthogonally to the gate lines, and further, The voltage of the pixel is kept constant, and a storage capacitor line (hereinafter referred to as a Cs line) in which electric charge is accumulated is also disposed. Further, in addition to this, there is a case where the backup wiring is arranged to repair the disconnected or short-circuited wiring. The invention can also be applied when measuring the electrical resistance of any of these wirings. In the present embodiment, as an example, the electric resistance between the wiring of the gate line, the source line, the Cs line, or the wiring is measured. In step S3, all the terminals of the gate line, the source line, and the Cs line are short-circuited.

Fig. 5 is a diagram showing an electric resistance measurer of the present embodiment in an equivalent circuit. The constant voltage power source 59 is incorporated in a power source that is a part of the resistance measuring unit 8 and is a power source. The equivalent circuit shown in FIG. 5( a ) is a state in which a short-circuit defect is present in the liquid crystal panel 2 to be measured, and the node 56 and the node 57 are electrically connected via the resistor 55 and the resistor 53 . The equivalent circuit shown in FIG. 5(b) is an equivalent circuit of the liquid crystal panel 2 which is free from short-circuit defects. The portion of the circuit surrounded by the broken line 58 represents the liquid crystal panel 2. Further, the circuit portion that is not surrounded, that is, the portion on the left side of the paper surface of the nodes 56 and 57, indicates the resistance measuring unit 8 and the pre-short circuit portion 10. Capacitor 54 represents a stray capacitance; resistor 53 represents a resistance value connected in parallel to capacitor 54; and resistor 55 represents a resistance value connected in series to capacitor 54.

The state of the closed switch 52 indicates that the resistance is being measured. By closing the switch 52, The constant voltage source 59 applies a voltage between the node 56 connected to the two wires to be measured and the node 57. When a short circuit occurs between the two wires to be measured, a current flows. The resistance measuring unit 8 measures the electric resistance between the node 56 and the node 57.

Further, the current can be measured instead of measuring the resistance. In this case, the current is measured, and the voltage value of the constant voltage source 59 is divided by the current value to obtain a resistance value. When there is no short circuit between the two connected wirings, no current flows, and the resistance value becomes infinite.

In the state in which the switch 52 is turned on, the switch 51 as the pre-short circuit portion 10 is closed, and all the terminals of the wiring or the wiring to be measured are short-circuited, and placed for a predetermined period of time to be naturally discharged. After the discharge, the switch 51 is turned on. The operation of closing the switch 51 and opening the switch 51 after a certain period of time is referred to as a pre-short circuit process. Then, in step S4, the wiring or the wiring for performing the resistance inspection is selected in accordance with various defect modes, and the probe 21 that is turned on is switched. The defect mode will be described later.

In step S5, the switch 52 of Fig. 5 is closed to perform a resistance check. In step S5, the resistance value between the selected wiring or the wiring is measured, and the presence or absence of the defect is checked by comparing the resistance value with the resistance value at the time of no defect.

Fig. 6 is an example of a change in current value after the switch 52 is closed; Fig. 6(a) shows a case where a short-circuit defect is present in the liquid crystal panel 2, and Fig. 6(b) shows a case where there is no short-circuit defect. Further, the vertical axis represents the current value I and the horizontal axis represents the time t. After the switch 52 is closed, the current immediately flows to both the capacitor 54 and the resistor 53 to start charging of the capacitor 54. At this time, when there is a short defect in the liquid crystal panel 2, as shown in FIG. 6(a), as the charging of the capacitor 54 approaches, the current flowing in the capacitor 54 gradually decreases, and the resistor 53 is referred to herein as a short defect. The current flowing in the part gradually increases. Finally, after the time t ₀ after the completion of the charging of the capacitor 54, the fixed current I ₀ continues to flow through the resistor 53.

On the other hand, when there is no short-circuit defect in the liquid crystal panel 2 and it is good, as shown in FIG. 6(b), the current does not flow after the time t _{0 of} completion of charging of the capacitor 54, and the measured resistance value becomes infinite.

(c) of FIG. 6 shows a pre-short circuit which is a step of short-circuiting all the terminals between the wirings or wirings to be measured before the resistance measurement in step S3, and the resistance measurement is performed by the previous method. Time and current values. The charging time of the capacitor 54 is not fixed, and the time is longer than the time t _{0 when} the charging of the capacitor shown in Fig. 6 (a) and Fig. 6 (b) is completed. That is, the time required for the resistance measurement varies.

In the present invention, in the step S3, all the terminals of the wiring or the wiring to be measured are short-circuited before the resistance measurement, and the capacitor 54 is discharged. Therefore, the charging of the capacitor 54 is started from the state of 0. Therefore, the time t _{0 at which} the charging of the capacitor 54 is completed is always fixed until the time for determining whether or not there is a short-circuit defect in the liquid crystal panel 2 is fixed, and the variation in the measurement time can be suppressed. Moreover, charging due to static electricity can be removed.

Fig. 7 is a view for explaining in detail the step of measuring the resistance value in the first embodiment. Fig. 7 shows changes in the resistance value of the short-circuit defective portion, R1 to R4 (resistance value R4 = ∞ and R3 > R2 > R1), and the change in the indication value R of the resistance measuring device from the start of the measurement is expressed by the elapse of time t.

Regarding the R4 in which the resistance value of the short-circuit-free defect portion is infinite, the indication value R is higher than the measurement limit at the time t ₀ at which the resistance of the capacitor 54 between the wirings is completed, and becomes an overload (OL, Over Load) ), thereby determining that there is no short circuit defect. Here, the overload indicates the state in which the resistance measuring unit 8 measures the maximum measurable resistance value. Since the maximum resistance value is a sufficiently large resistance value, it is judged that the overload state is no short-circuit defect. On the other hand, R1 to R3 of the defect short-circuit portion are limited, and after the indication value R is stabilized, the indication value R of the time t ₀ is compared with the specific threshold value T _R as the resistance value of the short-circuit defect portion. It can be determined whether there is a short circuit defect. For example, if the resistance value such as R3 is high, the resistance is such that there is no problem in the display of the liquid crystal panel 2, and it is judged to be a short defect when the resistance value is equal to or less than a certain threshold value T _R such as R1 or R2. .

In the first embodiment, by performing the pre-short circuit processing, it is possible to suppress the deviation from the time t ₀ until the indication value R of the resistance measuring device is stabilized. Therefore, by selecting the appropriate measurement time t ₀ for measurement, the resistance value can be correctly checked. defect.

However, the time t ₀ required until the indication value R is stabilized usually takes about 3 seconds. Therefore, for example, when a plurality of wirings such as a liquid crystal panel are inspected, since the number of times of measurement increases, the intermittent time of the resistance value measuring step becomes long.

Therefore, it is desirable to wait for the time t ₀ at which the indication value R is stable, and to determine whether or not there is a short-circuit defect in the transition period immediately after the start of the measurement before the indication value R is stabilized. As shown in FIG. 7, in the transition period after the start of the measurement, if the rate of change of the indication value R is obtained between time t ₀₁ and time t ₀₂ , it becomes Δr ₁ to Δr ₄ with respect to the resistors R1 to R4. Like.

When the resistance value of the short-circuit defect portion, that is, the indication value R of the change rate Δr and the time t ₀ is measured in advance, and the measurement data is collected and formed into a table, for example, as shown in FIG. 8, the change rate Δr and the resistance value of the short-circuit defect portion are Relationships become proportional relationships. Therefore, by determining the rate of change Δr of the indication value R and determining the resistance value predicted at time t ₀ , it is possible to determine whether or not there is a short circuit defect. Further, even if the change rate Δr is not proportional to the resistance value of the short-circuit defect portion according to the measurement conditions or the like, the correspondence relationship can be obtained from the measurement data in advance, and the presence or absence of the short-circuit defect can be determined by the same method.

Specifically, as shown, may be a value indicating the change of rate R with the particular threshold △ r 8 T _r comparing the △ r _1, △ r ₂ is smaller than the threshold value T _r of the case is determined by short-circuit defect. The rate of change Δr can be determined by measuring the difference between the measured values of the resistance at least two times from the start time t ₀₁ and the time t ₀₂ . For example, the initial time t ₀₁ is 100 ms after the start of the measurement, and the second time t ₀₂ is 300 ms after the start of the measurement, and can be set to a measurement time much earlier than the time t ₀ . Further, the specific threshold value T _r may be selected from an appropriate value by empirically selecting the data of the rate of change Δr and the resistance value collected from the actual measurement. In this manner, the resistance value is determined by determining the rate of change Δr of the indication value R during the transition period immediately after the start of the measurement, and the intermittent time of the resistance value measurement step can be shortened even when a plurality of wirings are inspected.

In the first embodiment, the rate of change Δr is obtained by using the difference between the indication values R obtained by measuring the resistance at least two times from the time t ₀₁ and the time t ₀₂ after the start of the measurement, but it is of course possible to perform the third time or more. In the resistance measurement, the change rate Δr is obtained by a plurality of indication values R obtained by linear interpolation, and is used in the resistance value measurement step, and the detection accuracy of the short-circuit defect can be further improved.

Further, depending on the state of the short-circuit defective portion or the like, the change rate Δr corresponding to the resistance value of the short-circuit defective portion can be detected even at the initial stage of the transition period, and in the resistance value measuring step, only The rate of change Δr of the indication value R is measured once at time t ₀₁ , and the rate of change Δr from time 0 is obtained. In this case, since the resistance measurement is performed only once in the initial period of the transition period, the measurement time can be further shortened.

Furthermore, the constant current source 59 can also be replaced by a constant current source. By closing the switch 52, a constant current is flowed between the node 56 connected to the two wires to be measured and the node 57. When a short circuit occurs between the two wires to be measured, a constant current flows. The resistance measuring unit 8 measures the voltage between the node 56 and the node 57, and divides the measured voltage value by the constant current value to obtain a resistance value. When there is no short circuit between the two tested wirings, no current flows, and the resistance value becomes infinite.

Here, it is assumed that the state of resistance measurement has not been performed. That is, the switch 52 is turned on. In FIG. 5(a), the capacitor 54 and the resistor 53 are closed, and the electric charge stored in the capacitor 54 is naturally discharged. On the other hand, in FIG. 5(b), the circuit is opened, and the electric charge accumulated in the capacitor 54 is not discharged. Therefore, the liquid crystal panel which does not have a short-circuit defect is not subjected to natural discharge, and is affected by resistance measurement or static electricity in other wirings, and the time until the dielectric absorption converges greatly changes.

In (a) to (c) of FIG. 9 , as an example, the position of the defective portion 23 which is a short-circuit portion of the wiring generated in the pixel portion 17 is schematically shown. (a) of FIG. 9 shows a defect portion 23 in which the wiring X and the wiring Y are short-circuited at the intersection portion in the liquid crystal panel in which the gate line and the source line-like wiring X and the wiring Y intersect. Switching the conductive probe 21 to the group of 21a and 21d or the group of 21b and 21c shown in FIG. 3, and measuring the wiring between the wirings X1 to X10 and the wirings Y1 to Y10 in a one-to-one manner. The resistance value, whereby the presence or absence of the defective portion 23 and the position can be specified.

Fig. 9(b) shows a defect portion 23 in which a short circuit occurs between wirings of the wiring X adjacent to the gate line and the Cs line, for example. The short-circuit portion 23 is configured by switching the conductive probe 21 to the odd-numbered number of 21b and the even-numbered number of 21d, and measuring the resistance value between the adjacent wirings of the wirings X1 to X10, and the defective portion 23 can be specified. Wiring.

Fig. 9(c) shows a defect portion 23 in which a short circuit occurs between wirings of the wiring Y adjacent to the source line and the Cs line, for example. The defect portion 23 is configured to switch the conductive probe 21 to the group of the odd number of 21a and the even number of 21c, and measure the resistance value between the adjacent wirings of the wirings Y1 to Y10, and the defective portion 23 can be specified. Wiring.

In step S6, it is determined whether or not the infrared inspection is performed based on the presence or absence of the defective portion 23 inspected in step S5. In the case of the defective portion 23, the process proceeds to step S7 for the infrared ray inspection, and the non-defective portion 23 is not performed, and the process proceeds to step S10 without performing the infrared ray inspection. This step S6 can be referred to as part of the resistance value determination step.

For example, as shown in FIG. 9(a), when the defective portion 23 is formed in the portion where the wiring X and the wiring Y intersect, the wiring X4 and the wiring Y4 are detected to have abnormalities due to the resistance check between the wirings, so that a specific defect can be specified. The position of the department 23. Therefore, in the case of the defective portion 23 shown in Fig. 9(a), it is not necessary to use the infrared ray inspection to specify its position in the step S7. In other words, if each group of the combination of the wiring X and the wiring Y is subjected to the resistance inspection, the position can be specified, so that it is not necessary to perform the infrared inspection. However, it takes a long time because the number of combinations is too large. For example, in the case of a full-height LCD panel, due to wiring X For 1080, the wiring Y is 1920, so the total combination is about 2.07 million. If the resistance check is performed for each of such a combination, the intermittent time becomes long, and the inspection processing ability is drastically lowered, which is not realistic. Therefore, the resistance check can be reduced by totaling all the combinations of the wiring X and the wiring Y and performing resistance inspection. For example, if the resistance check is performed between the wiring X having one total and the wiring Y having one total, the number of times of the resistance inspection is only one. However, although a short circuit between wirings can be detected by a resistance check, a specific position cannot be obtained. Therefore, it is necessary to check the position of the specific defect portion 23 by using infrared rays.

On the other hand, when the defective portion 23 is formed between the adjacent wiring lines as shown in FIG. 9(b) or FIG. 9(c), a pair of wirings such as a defective portion between the wiring X3 and the wiring X4 can be specified. However, since the position of the defective portion 23 is not specified in the longitudinal direction of the wiring, it is necessary to inspect the position of the specific defective portion 23 by infrared rays.

It takes a long time because the resistance check of the adjacent wiring closets is a large number. For example, in the case of a liquid crystal panel for full-height image quality, the number of resistance inspections between adjacent wirings X is 1079, and the number of resistance inspections between adjacent wirings Y is 1919. In the case of the resistance check between the adjacent wirings X as in the case of Fig. 9(b), if the resistance check is performed between all the X odd numbers and all the X even numbers, the number of times of the resistance check is only one. In the case of the resistance check between the adjacent wires Y as in the case of Fig. 9(c), if the resistance check is performed between all the Y odd numbers and all the Y even numbers, the number of times of the resistance check is only one. However, although the short circuit between the wirings can be detected by the resistance check, the position cannot be specified. Therefore, it is necessary to check the position of the specific defect portion 23 by using infrared rays. Therefore, in step S6, it is determined that the liquid crystal needs to be inspected by infrared rays. Panel 2 performs an infrared inspection.

In step S8, in order to detect the infrared light from the defective portion 23 which generates a current by the application of the voltage and generates heat, the defect portion 23 is photographed by the infrared camera, and the position of the defective portion 23 is specified. In the present embodiment, the infrared camera 5a for macro measurement and the infrared camera 5b for microscopic measurement are included. First, the infrared camera 5a for macro measurement, which can accommodate a wide range of the liquid crystal panel 2 in the field of view, is scanned as needed. The position of the specific defect portion 23 is measured by the infrared camera 5a. Then, the vicinity of the heat generating portion can be measured using the infrared camera 5b for microscopic measurement as needed. Since the position of the heat generating portion is specified by the infrared camera 5a for macro measurement, the camera can be moved so that the heat generating portion is positioned in the field of view of the infrared camera 5b for microscopic measurement, and the coordinate position of the defective portion 23 can be specified with high precision, or Perform measurement on the information such as the shape required for correction. In the present embodiment, the infrared camera 5a for macro measurement and the infrared camera 5b for microscopic measurement are imaged in two stages. However, the present invention is not limited thereto, and one infrared camera may be used. The stage is the composition of photography.

Further, the optical camera 16 of Fig. 2 is controlled by the main control unit 7 of Fig. 1 for photographing the short-circuit defect detected by the infrared camera 5b for microscopic measurement as a visible image. Alternatively, it may be a coaxial optical unit that also serves as the optical camera 16 and the above-described laser irradiation device.

In step S9, it is judged whether or not all the inspections of the various defect modes are completed in the liquid crystal panel 2 under inspection, and when there is an unchecked defect mode, the process returns to step S3. Then, after all the terminals of the measurement target are pre-short-circuited, the defect inspection is repeated. Here, the defect mode is the defect part shown in FIG. 23 types. There are three defect modes shown in FIG. That is, the short-circuit defect mode of the wiring X and the wiring Y of FIG. 9(a), the short-circuit defect mode between the wirings X of FIG. 9(b), and the short-circuit defect mode between the wirings Y of FIG. 9(c).

In step S10, it is judged whether or not the defect inspection of all the liquid crystal panels 2 is completed for the mother substrate 1 under inspection, and if there is any unchecked liquid crystal panel 2, the process returns to step S2. Then, the probe is moved to the liquid crystal panel 2 which is the next inspection target, and the defect inspection is repeated.

Fig. 10 is a view showing the wiring of the relay corresponding to the three defect modes described using Fig. 9. The resistance measuring device 415 is a part of the resistance measuring unit 8, and measures resistance. The power source 416 is a portion of the voltage applying portion 9 that applies a voltage to the wiring or wiring of the liquid crystal panel 2. The dotted line blocks 401, 404, 407, and 410 surrounded by the broken line of Fig. 10 indicate the probes 21a to 21d. The dotted line block 401 indicates a probe connected to the terminal portion of the odd-numbered wiring X, the broken line block 404 indicates a probe connected to the terminal portion of the even-numbered wiring X, and the broken-line block 407 indicates a terminal portion connected to the odd-numbered wiring Y. The probe and the dotted line block 410 indicate probes connected to the terminal portions of the even-numbered wires Y. The dashed blocks 402, 403, 405, 406, 408, 409, 411, 412, 413, 414 represent relays. The dotted block 402, 403 is a relay corresponding to the dotted block 401; similarly, the dotted block 405, 406 is a relay corresponding to the broken block 404; the dotted block 408, 409 is a relay corresponding to the broken block 407 The dashed blocks 411, 412 are relays corresponding to the dashed block 410. Hereinafter, it is assumed that the relay in the dotted line block N is the relay N. For example, the relay within the dashed block 402 is the relay 402.

Relays 402, 405, 408, 411 are connected to electricity via relay 413 The measured value 415 and the positive terminal of the power source 416 are blocked. The relays 403, 406, 409, and 412 are connected to the negative polarity terminals of the resistance measuring device 415 and the power source 416 via the relay 414. Relay 413 is a relay that is connected to the terminals of the resistance measuring device. Relay 414 is a relay that is connected to the terminals of power source 416. By switching the plurality of relays, the short-circuit processing shown in step S3, the resistance measurement shown in step S4, and the voltage application shown in step S7 can be performed separately.

Figure 11 is a table showing the switches of the relays shown in Figure 10. In the short-circuit processing, all the connections of the probes of the broken line blocks 401, 404, 407, and 410 are closed, and all the terminals of the wiring or wiring are short-circuited. At the same time, the relays 413, 414 are all turned on, and the resistance measuring device 415 and the power source 416 are cut away.

In the resistance measurement and the voltage application, the connections of the probes of the broken line blocks 401, 404, 407, and 410 are switched in accordance with the defect mode. For example, in the resistance measurement of the short-circuit defect mode of the wiring X and the wiring Y as shown in FIG. 9(a), the relays 402, 405, 409, 412, and 413 are closed, and the relays 403, 406, 408, 411, and 414 are turned on. The odd and even wirings X are connected to the positive terminal of the resistance measuring device 415, and the odd and even wirings Y are connected to the negative terminal of the resistance measuring device 415. Further, as shown in FIG. 9(a), in the voltage application of the short-circuit defect mode of the wiring X and the wiring Y, the relays 402, 405, 409, 412, and 414 are closed, and the relays 403, 406, 408, 411, and 413 are turned on. The odd and even wirings X are connected to the positive terminal of the power supply 416, and the odd and even wirings Y are connected to the negative terminal of the power supply 416.

Thus, by switching a plurality of relays, the matching of the liquid crystal panel 2 can be changed. Wiring between the wire and the resistance tester and the power supply. In addition, the defect pattern of the wiring X, the wiring Y, the Cs line, and the backup wiring (for example, the Cs line defect mode, the defect pattern of the wiring X and the Cs line, the defect mode of the wiring Y and the Cs line, the wiring X and the backup wiring) The defect mode, the wiring Y and the defect pattern of the backup wiring) may be subjected to short-circuit processing, resistance measurement, and voltage application by appropriately adding a relay.

According to the present embodiment, before the resistance inspection, the terminals to be inspected are short-circuited, and the electric charge charged between the terminals is temporarily set to zero. The electric resistance is measured in a state where the charging is 0, whereby the initial state can be fixed and suppressed. Variation or deviation in convergence time. The presence or absence of a defect is determined between the terminals, and when it is determined that there is a defect, the resistance value of the short-circuit path of the liquid crystal panel 2 is obtained. Further, by applying a voltage specific to the resistance value to the liquid crystal panel 2, any one of the defective portion 23 or the wiring portion is sufficiently heated, so that the position of the defect can be easily recognized at the time of infrared inspection.

In the present embodiment, a method is described in which the wiring of the gate line, the source line, the Cs line, or the wiring is made when measuring the resistance between the gate line, the source line, the Cs line wiring, or the wiring. After pre-short-circuiting all the terminals, for example, the resistance measurement of the gate line and the source line is performed, and then all the terminals of the gate line, the source line, the Cs line wiring or the wiring line are pre-short-circuited again, and then the gate line is performed this time. The resistance measurement with the Cs line is pre-short-circuited to all the terminals to be measured before the resistance measurement is performed as described above. In the case of this method, since all the terminals are short-circuited and discharged each time, the charging of the capacitor is always 0 with respect to any of the wirings, and since static electricity is also removed, the variation of the measurement time is extremely small, which is preferable. However, it is not limited to this method, for example For example, before the resistance of the gate line and the source line is measured, only the gate line and the source line are pre-short-circuited, and resistance measurement is performed, and only the wirings of the measurement target are pre-short-circuited each time.

Furthermore, the step of short-circuiting the terminals of the wiring may be further performed after at least one of the steps S5 or S8. The short-circuiting step after the measurement of the resistance value performed in the step S5 is completed, and the electric charge charged to the liquid crystal panel 2 by the resistance value measurement performed in the step S5 can be discharged. Alternatively, the short-circuiting step after the defect position specified in the step S8 is terminated may discharge the electric charge charged to the liquid crystal panel 2 by the voltage application applied in the step S8. By the short-circuiting step, the wiring defect inspection apparatus 100 inspects the state in which the mother substrate 1 outside the unloading apparatus is discharged. As a result, it is possible to prevent electrostatic breakdown of the mother substrate 1 or deterioration in display quality.

<Embodiment 2>

In the first embodiment, the configuration of the infrared camera 5 in which the photographic defect portion 23 is provided as shown in FIG. 1 has been described. However, the configuration may be such that only the resistance measurement is performed to check for the presence or absence of a defect. Fig. 12 is a block diagram showing the configuration of the wiring defect device 200 of the second embodiment. The configuration of the first embodiment is the same as that of the first embodiment except that the infrared camera 5 for obtaining an infrared image shown in FIG. 1 and the camera moving mechanism 6 for moving the infrared camera 5 on the liquid crystal panel 2 are not included.

Fig. 13 is a flowchart showing a wiring defect inspection method using the wiring defect inspection device 200 of the second embodiment. As shown in FIG. 13, in the wiring defect inspection method of this embodiment, the wiring defect inspection is sequentially performed on the plurality of liquid crystal panels 2 formed on the mother substrate 1 by the steps S91 to S97.

First, in step S91, the mother substrate 1 is placed on the alignment stage 11 of the wiring defect inspection device 200, and the position of the substrate is adjusted so as to be parallel to the XY coordinate axis. Then, in step S92, the probe moving mechanism 4 moves the probe 3 to the upper portion of the liquid crystal panel 2 to be inspected, and the probes 21a to 21d are brought into contact with the terminal portions 19a to 19d of the liquid crystal panel 2. Here, in step S93, all the terminals of the wiring to be measured or the wiring are pre-short-circuited.

Next, in step S94, in accordance with various defect modes, the wiring or the wiring for performing the resistance inspection is selected, and the probe 21 that is turned on is switched. A resistance check is performed in step S95. In step S95, the resistance value of the selected wiring or wiring is measured, and the resistance value is compared with the resistance value in the case of no defect, and the presence or absence of the defect is checked. In step S96, it is judged whether or not all the inspections of the various defect modes have been completed in the liquid crystal panel 2 under inspection, and when there is an unchecked defect mode, the flow returns to step S93. Then, after all the terminals of the measurement target are pre-short-circuited, the defect inspection is repeated. In step S97, the mother substrate 1 under inspection is judged whether or not the defect inspection of all the liquid crystal panels 2 is completed. If the unchecked liquid crystal panel 2 remains, the flow returns to step S92. Then, the probe is moved to the liquid crystal panel 2 which is the next inspection target, and the defect inspection is repeated.

According to this configuration, since the resistance measurement is performed in another device, the resistance measurement and the infrared camera imaging can be performed in parallel, and the processing capability can be improved.

<Embodiment 3>

Furthermore, the present invention can of course be achieved by supplying a recording medium on which a program code for realizing the function of the above-described embodiment is recorded to Other systems or devices from which the computer CPU of the system or device reads and executes the code stored in the recording medium.

In this case, the program code read from the recording medium itself realizes the functions of the above embodiment, and the recording medium on which the code is recorded constitutes the present invention. Moreover, the above code may be downloaded to a recording device from another computer system via a transmission medium such as a communication network.

Moreover, it goes without saying that the function of the above-described embodiment can be realized not only by the execution of the code read by the computer, but also by an OS (Operating System) running on the computer or the like based on the instruction of the code. All of the actual processing, by the processing, realizes the function of the above embodiment.

Further, it goes without saying that the program code read from the recording medium is written to the memory of the function expansion board inserted in the computer or the function expansion unit connected to the computer, based on the instruction of the code. The CPU or the like provided in the function expansion board or the function expansion unit performs some or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

When the present invention is applied to the above-described recording medium, the program code corresponding to the previously described flow is stored in the recording medium.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. Various modifications may be made without departing from the spirit and scope of the invention as described in the appended claims.

(summary of the invention)

The wiring defect inspection method according to the present invention is characterized in that the detection of the short-circuit portion of the wiring of the semiconductor substrate is performed as follows: a pre-short step of short-circuiting between the terminals of the wiring to be inspected; and a resistance value measuring step After the pre-short step, the resistance value of the wiring to be inspected is measured to determine the presence or absence of the wiring short-circuit portion.

Further, the pre-short step may be characterized by short-circuiting all the terminals of the inspection object. Further, in the resistance value measuring step, the resistance value may be determined before the indication value of the resistance measuring device of the wiring is stabilized. Further, in the resistance value measuring step, the resistance value may be determined based on a rate of change of the indication value. Further, in the resistance value measuring step, the change rate may be calculated by measuring the measured value and the measurement time from the start of the measurement, or the rate of change may be calculated from the indicated value at different times. feature. Further, the resistance value measuring step may be characterized in that the wiring short-circuit portion is determined when the change rate is less than a specific value. Furthermore, the step of generating a voltage for applying a voltage to the short-circuit path including the short-circuit portion of the semiconductor substrate in the resistance-measurement step determined to have the wiring short-circuit portion, and causing the short-circuit path to be generated And a position-specific step of specifying the position of the short-circuit portion of the wiring by infrared imaging of a short-circuit path of heat generated in the heat-generating step. Further, it may be characterized by a step of short-circuiting the terminals of the wiring after at least one of the resistance value measuring step or the position specifying step.

A wiring defect inspection device according to the present invention is characterized in that it is a detector for detecting a short-circuit portion of a semiconductor substrate, and includes a pre-short circuit portion a voltage between the terminals of the inspection target; a voltage application unit that applies a voltage to the wiring of the inspection target; a resistance measurement unit that measures a resistance value of the wiring; and a control unit that controls the voltage application unit; The resistance value measured by the resistance measuring unit determines whether or not the wiring short-circuit portion is present. Further, the wiring defect inspection device may further include an imaging unit.

The wiring defect inspection program according to the present invention is characterized in that the wiring defect inspection device is operated by an operator and the computer functions as the above-described respective mechanisms.

The wiring defect inspection program recording medium of the present invention is characterized in that the wiring defect inspection program described above is recorded.

[Industrial availability]

The present invention can be used to inspect a wiring state of a semiconductor substrate having wiring such as a liquid crystal panel.

1‧‧‧ mother substrate

2‧‧‧LCD panel

3‧‧‧ probe

4‧‧‧Probe moving mechanism

5a‧‧‧Infrared camera

5b‧‧‧Infrared camera

6‧‧‧ Camera moving mechanism

7‧‧‧Main Control Department

8‧‧‧Resistance Measurement Department

9‧‧‧Voltage application department

10‧‧‧Pre-short circuit

11‧‧‧Aligning the stage

12‧‧‧Optical camera

13a‧‧‧rail

13b‧‧‧rail

13c‧‧‧rail

13d‧‧‧rails

13e‧‧‧rail

13f‧‧‧rail

14a‧‧‧Installation Department

14b‧‧‧Installation Department

14c‧‧‧Installation Department

14d‧‧‧Installation Department

16‧‧‧Optical camera

17‧‧‧Pixel Department

18‧‧‧Circuit wiring department

19a‧‧‧Terminal Department

19b‧‧‧Terminal Department

19c‧‧‧Terminal Department

19d‧‧‧Terminal Department

21a‧‧‧Probe Department

21b‧‧‧Probe Department

21c‧‧‧ Probe Department

21d‧‧‧ Probe Department

23‧‧‧Defects (wiring short circuit)

51‧‧‧ switch

52‧‧‧ switch

53‧‧‧resistance

54‧‧‧ capacitor

55‧‧‧resistance

56‧‧‧ nodes

57‧‧‧ nodes

59‧‧‧ Constant voltage power supply

100‧‧‧Wiring defect inspection device

415‧‧‧resistance tester

416‧‧‧Power supply

P1~P8‧‧‧ LCD panel

1 (a) and (b) are a block diagram showing a configuration of a wiring defect inspection device according to a first embodiment of the present invention, and a perspective view showing a configuration of a mother substrate having a liquid crystal panel.

Fig. 2 is a perspective view showing the configuration of the wiring defect inspection device.

3(a) and 3(b) are plan views of a liquid crystal panel and a probe used in the embodiment of the present invention.

Fig. 4 is a flow chart showing a method of inspecting a wiring defect according to the first embodiment of the present invention.

5(a) and 5(b) show an embodiment of the present invention in an equivalent circuit.

6(a), (b) and (c) are diagrams showing the elapsed time and current values in the embodiment of the present invention.

Fig. 7 is a view for explaining a resistance value measuring step in the embodiment of the present invention.

Fig. 8 is a graph showing the relationship between the rate of change and the resistance value used in the resistance value measuring step in the embodiment of the present invention.

Figs. 9(a), (b) and (c) are schematic views showing defects of a pixel portion used in the embodiment of the present invention.

Fig. 10 is a view for explaining the wiring of the relay corresponding to the three defect modes in the first embodiment of the present invention.

Fig. 11 is a table showing a switch of a relay according to the first embodiment of the present invention.

Fig. 12 is a block diagram showing the configuration of a wiring defect inspection device according to a second embodiment of the present invention.

Fig. 13 is a flow chart showing a method of inspecting a wiring defect according to the second embodiment of the present invention.

Fig. 14 is a view for explaining a prior art wiring defect detecting method.

Fig. 15 is a view for explaining a prior art wiring defect detecting method.

1‧‧‧ mother substrate

2‧‧‧LCD panel

3‧‧‧ probe

4‧‧‧Probe moving mechanism

5‧‧‧Infrared camera

6‧‧‧ Camera moving mechanism

7‧‧‧Main Control Department

8‧‧‧Resistance Measurement Department

9‧‧‧Voltage application department

10‧‧‧Pre-short circuit

100‧‧‧Wiring defect inspection device

P1~P8‧‧‧ LCD panel

Claims (6)

A method for inspecting a wiring defect, characterized in that it is a method of detecting a short-circuit portion of a wiring in a semiconductor substrate, and performing a pre-shorting step of short-circuiting between terminals of a wiring to be inspected; and a resistance value measuring step After the pre-short step, the resistance value of the wiring to be inspected is measured to determine the presence or absence of the wiring short-circuit portion. The wiring defect inspection method of claim 1, wherein the pre-short circuit step short-circuits all of the terminals of the inspection object. The wiring defect inspection method according to claim 1 or 2, wherein in the resistance value measuring step, the resistance value is determined based on a rate of change of the indication value. The wiring defect inspection method of claim 1, comprising: a heat generating step of applying a voltage to a short-circuit path including the wiring short-circuit portion of the semiconductor substrate having the wiring short-circuit portion in the resistance value measuring step; The short-circuit path generates heat; and the position-specific step of photographing the short-circuit path of the heat generation in the heat-generating step by infrared rays, and specifying the position of the short-circuit portion of the wiring. The wiring defect inspection method of claim 4, comprising the step of short-circuiting the terminals of the wiring after at least one of the resistance value measuring step or the position specifying step. A wiring defect inspection device characterized in that it is a detector for a short-circuit portion of a wiring in a semiconductor substrate, and includes: a short-circuiting portion that short-circuits between terminals of the wiring to be inspected, a voltage applying portion that applies a voltage to the wiring to be inspected, a resistance measuring portion that measures a resistance value of the wiring, and a control portion that controls the voltage application And determining whether or not the wiring short-circuit portion is present based on a resistance value measured by the resistance measuring unit.