JP4394113B2 - Circuit pattern inspection apparatus and circuit pattern inspection method - Google Patents

Description

  The present invention relates to a circuit pattern inspection apparatus and a circuit pattern inspection method capable of inspecting the quality of a conductive pattern formed on a substrate.

  When manufacturing a circuit board formed by forming a conductive pattern on a substrate, it is necessary to inspect whether the conductive pattern formed on the substrate is disconnected or short-circuited.

  Conventionally, as a method for inspecting a conductive pattern, for example, as in Patent Document 1, a pin is brought into contact with both ends of a conductive pattern, and an electric signal is supplied from the pin on one end side to the conductive pattern. A contact-type inspection method (pin contact method) for conducting a continuity test of a conductive pattern by receiving the electric signal is known. The electric signal is supplied by standing a metal probe on all terminals and causing a current to flow through the conductive pattern.

This pin contact method has an advantage that the S / N ratio is high in order to directly contact the pin probe.
However, in recent years, with the increase in the density of the conductive pattern, the wiring pitch for connection has also been made finer, and those having a size of less than 50 μm have appeared. A probe card composed of a large number of narrow-pitch probes has a high manufacturing cost.

At the same time, every time the wiring pattern is different (for each inspection object), a new probe card must be manufactured for use. For this reason, the inspection cost is increased, which has been a major obstacle to reducing the cost of electronic components.
In addition, the probe card is fragile due to its fine structure, and it has always been necessary to consider the risk of breakage in actual use.

  For this reason, as shown in Patent Document 2, a pin probe is directly brought into contact with one end of a conductor pattern to be inspected, and an inspection signal containing an AC component is applied. There has also been proposed a contact-non-contact combination method in which the inspection signal is detected through capacitive coupling by positioning in a state of being separated and separated.

In this contact / non-contact combination method, the probe at the other end of the pattern line does not need to be in direct contact with the pattern like the pin probe, so that positioning accuracy can be roughened. Furthermore, since the non-contact portion can be shared for a plurality of pattern lines, the number of probes can be reduced. Therefore, it is possible to cope with a case where the interval between the conductive patterns is fine.
JP 62-269075 A JP-A-11-72524

  However, in the contact / non-contact combination method, the probe disposed at both ends of the conductive pattern and the detection signal processing from the probe are provided according to the conductive pattern arrangement interval. Is a predetermined type, and if the conductive pattern is different, the jig must also be manufactured according to the pattern.

  In addition, in the contact-noncontact combination method, one end of the conductor pattern to be inspected to be directly brought into contact with the pin probe is also made minute, and it is difficult for the pin probe to come into contact. In addition, there is an unavoidable risk of damaging the conductor pattern to be inspected due to contact with the pin probe.

  Further, when the probe (electrode) is opposed to the pattern to be inspected in a non-contact manner for capacitive coupling, it is desired that the distance between them is constant.

  The present invention has been made with the object of solving the above-described problems of the prior art, and provides an inspection apparatus and inspection method capable of handling a fine wiring pattern with a simple configuration and changing the wiring pattern. is there. As a means for achieving the object, for example, an embodiment of the invention according to the present invention has the following configuration.

For example, the circuit pattern inspection apparatus supplies an AC inspection signal to one inspection target pattern among a plurality of conductive patterns formed in a substantially bar shape with a predetermined width in the inspection target region and in the vicinity of both ends. A circuit pattern inspection apparatus for inspecting the inspection target pattern by detecting a signal from the inspection target pattern, the supply means having a supply electrode for supplying the inspection signal to one end of the inspection target pattern; and the inspection signal Detecting means having at least two detection electrodes capacitively coupled to the inspection target pattern and the pattern adjacent to the inspection target pattern, respectively, and the supply electrode and the detection electrode, respectively, Mounted on a support member and sequentially capacitively coupled to the opposing inspection target patterns while being separated from the inspection target pattern And a first moving means for moving across the both ends of the inspection target pattern, wherein the first moving means passes the supply electrode and the detection electrode over one end and the other end of the same inspection target pattern. The detection means detects a defect due to disconnection or short circuit of the inspection target pattern from the inspection signal obtained by the change of the capacitive coupling in the inspection target pattern and the adjacent pattern.

Further, in the circuit pattern inspection method, an AC inspection signal is supplied to one inspection target pattern among a plurality of conductive patterns formed in a substantially bar shape with a predetermined width in the inspection target region and in the vicinity of both ends. A supply means having a supply electrode; and a detection means having a detection electrode for detecting each signal simultaneously and individually from the inspection object pattern and a pattern adjacent to the inspection object pattern, and the quality of the inspection object pattern is determined. A pattern inspection method in a circuit pattern inspection apparatus for inspecting, wherein the inspection signal is supplied to the inspection target pattern separated from the supply electrode, and the detection means includes the inspection target pattern and a pattern adjacent to the inspection target pattern; And capacitively coupled separately from at least two rows of patterns, while maintaining the capacitive coupling state, The inspection signal obtained by the supply electrode and the detection electrode moving synchronously so as to pass over one end and the other end of the same inspection target pattern, and the change in the capacitive coupling in the inspection target pattern and the adjacent pattern To detect a defect due to disconnection or short circuit of the inspection object pattern.

  As described above, according to the present invention, it is possible to reliably detect defects in the inspection target pattern. Furthermore, it is possible to easily recognize the pattern defect status, and it is possible to specify a specific defect location. Furthermore, even if the surface to be inspected has irregularities, the pattern can be reliably inspected without damaging the pattern.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the following description, a circuit pattern inspection apparatus that inspects the quality of a dot matrix pattern before bonding in a dot matrix display panel that forms a liquid crystal display panel as a pattern to be inspected is taken as an example.

  However, the present invention is not limited to the examples described below, and is not limited as long as it is an inspection target pattern in which at least the vicinity of both ends of the inspection target region is formed in a row.

[First Embodiment of the Invention]
FIG. 1 is a diagram for explaining the principle of pattern inspection according to an embodiment of the present invention.
In FIG. 1, reference numeral 10 denotes a substrate on which conductive patterns to be inspected according to the present embodiment are arranged. In this embodiment, a glass substrate used for a liquid crystal display panel is used.

  On the surface of the glass substrate 10, conductive patterns 15 for forming a dot matrix display panel to be inspected by the circuit pattern inspection apparatus according to the present embodiment are arranged in rows at regular intervals. In the conductive pattern example shown in FIG. 1, the widths of the patterns 15 are substantially the same, and the intervals between the patterns are substantially equal. However, in the present embodiment, the inspection can be performed in the same manner even if the pattern intervals are not equal.

  Reference numeral 20 denotes a sensor unit, 30 denotes an inspection signal supply unit, 50 denotes an analog signal processing circuit that processes a detection signal from the sensor unit 20 and outputs it to the control unit 60, and 60 controls the entire inspection apparatus according to the present embodiment. 70 is a robot controller for controlling the scalar robot 80, 80 is for positioning and holding the liquid crystal panel 10 at the inspection position and supplying the sensor electrode of the sensor unit 20 and the inspection signal supply unit 30 according to the control of the robot controller 70. This is a scalar robot that scans so that the electrodes sequentially traverse all connection terminals of the conductive pattern to be inspected of the liquid crystal panel 10.

  In the present embodiment, the scalar robot 80 is configured to be capable of three-dimensional positioning in order to position the inspection target substrate (liquid crystal panel) 10 at a predetermined inspection position. Similarly, three-dimensional positioning control can be performed so that the sensor unit 20 and the inspection signal supply unit 30 are moved on the inspection target pattern while being kept at a predetermined distance from the surface of the inspection target substrate 10.

  In the above description, an example in which the scalar robot 80 moves the sensor unit 20 and the inspection signal supply unit 30 on the inspection target pattern while maintaining a predetermined distance from the surface of the inspection target substrate 10 has been described. However, the present embodiment is not limited to the above example. The sensor unit 20 and the inspection signal supply unit 30 are fixed, the inspection target substrate 10 is the sensor unit 20, and the tip electrode 25 of the inspection signal supply unit 30. , 35 may be controlled to move the substrate while maintaining a predetermined distance from the surface. Even if it controls in this way, the completely same effect is obtained.

  In actual inspection control, when the pattern intervals are not equal or when the pattern pitches at the two ends are different, the movement distance of the sensor electrode 25 and the movement distance of the supply electrode 35 are synchronized with each other. It is necessary to control at least a part of the sensor electrode 25 so that the supply electrode 35 is at the other end position of the pattern that is actually supplying the inspection signal. By controlling in this way, even if each pattern interval is not equal, or even if the pattern pitches at the two ends are different, it can be dealt with by simply controlling the moving speed of both electrodes of the scalar robot.

  A sensor electrode 25 and a supply electrode 35 are disposed on at least the front end surfaces of the sensor unit 20 and the inspection signal supply unit 30 according to the present embodiment. The sensor electrode 25 and the supply electrode 35 are made of metal, for example, copper (Cu) or gold (Au). Each electrode may be covered with an insulating material for protection. Further, for example, a semiconductor may be used as an electrode, but the reason why the electrode is formed of metal is that the capacitance between the conductive pattern and the conductive pattern can be increased.

  The inspection signal supply unit 30 is moved by the scalar robot 80 so as to cross one terminal portion of the inspection target pattern such as the liquid crystal panel 10 and sequentially supplies inspection signals to each inspection target pattern via capacitive coupling. In addition, it is desirable that the width of the supply electrode 35 at the front end be, for example, less than the pattern pitch of the inspection target pattern (the pattern width of the inspection pattern and the size of the pattern gap).

  This is because when the width of the supply electrode 35 is larger than the pattern pitch of the inspection target pattern, the sensor electrode 25 of the sensor unit 20 detects the inspection signal from the inspection target pattern other than the inspection target pattern when detecting the inspection signal. Because it will end up.

  However, the width of the supply electrode 35 does not necessarily have to be equal to or smaller than the pattern pitch of the inspection target pattern. If the plurality of inspection target patterns and a pattern adjacent to this pattern can be grasped, this embodiment will be described in detail later. Inspection can be performed by the inspection method.

  The sensor unit 20 is moved by the scalar robot 80 so as to cross one terminal portion of the inspection target pattern such as the liquid crystal panel 10 and is sequentially supplied to each inspection target pattern by the inspection signal supply unit 30 via capacitive coupling. The inspection signal is detected, and it is desirable that the width of the sensor electrode 25 at the tip is wider than the width of the supply electrode 35 by at least one pitch of the inspection target pattern, for example.

  A detection signal from the sensor unit 20 is sent to the analog signal processing circuit 50 and subjected to analog signal processing. The analog signal subjected to the analog signal processing by the analog signal processing circuit 50 is sent to the control unit 60, and the quality of the inspection target pattern with which the inspection signal supply unit 30 of the liquid crystal panel 10 is in contact is determined. The control unit 60 also performs control to supply the inspection signal to the inspection signal supply unit 30.

  The analog signal processing circuit 50 includes an amplifier 51 that amplifies the detection signal from the sensor unit 20, a bandpass filter 52 that removes a noise component of the detection signal amplified by the amplifier 51 and passes the detection signal, and a bandpass filter 52. And a smoothing circuit 54 that smoothes the detection signal that has been full-wave rectified by the rectifier circuit 53. Note that the rectifier circuit 53 that performs full-wave rectification and the smoothing circuit 54 that smoothes the detection signal are not necessarily provided.

  The control unit 60 controls the entire inspection apparatus according to this embodiment, and temporarily stores a computer (CPU) 61, a ROM 62 that stores control procedures of the CPU 61, processing progress information and detection signals of the CPU 61, and the like. RAM 63 for storing, A / D converter 64 for converting an analog signal from the analog signal processing circuit 50 into a corresponding digital signal, a signal supply unit 65 for supplying an inspection signal to be supplied to the inspection signal supply unit 30, an inspection result and an operation A display unit 66 for displaying instruction guidance and the like is provided.

  The signal supply unit 65 generates, for example, an AC 200 KHz, 200 V sine wave signal as an inspection signal, and supplies the sine wave signal to the inspection signal supply unit 30. In this case, the band-pass filter 52 is a band-pass filter that passes 200 kHz which is the inspection signal. Needless to say, the inspection signal is not limited to a sine wave signal, and may be a rectangular wave or a pulse wave as long as it is an AC signal.

  The inspection control of the conductive pattern of the present embodiment having the above configuration will be described below with reference to the flowchart of FIG. FIG. 2 is a flowchart for explaining the inspection control of the inspection apparatus according to the present embodiment.

  When inspection is performed by the inspection apparatus according to the present embodiment, the glass substrate on which the inspection target conductive pattern is formed is transported on a transport path (not shown) to the circuit pattern inspection apparatus position (work position) according to the present embodiment. It will be. For this reason, first, in step S1, the liquid crystal panel 10 to be inspected is set in the inspection apparatus. In this case, the substrate to be inspected that has been automatically transferred may be set on the inspection apparatus by a transfer robot (not shown), or may be set directly by the operator. When the inspection target is set in the inspection apparatus, the control unit 60 activates the robot controller 70 to control the scalar robot 80 and positions the inspection target at the inspection position.

  Subsequently, in step S3, the inspection signal supply unit 30 is supplied to the initial position on the one end portion side of the inspection target inspection target pattern 15 of the inspection target (liquid crystal panel) 10 (the end of the inspection target pattern position that is separated by a predetermined distance). The electrode 35 is positioned, and the sensor electrode 25 of the sensor unit 20 is transported and positioned at an initial position on the other end side of the inspection target pattern (the inspection target pattern position at the end that is separated by a predetermined distance).

  In this embodiment, the gap (distance between the inspection target pattern and the electrode) is maintained in the range of 100 μm to 200 μm, for example. However, the gap is not limited to the above example, and the gap in the present embodiment is determined according to the size of the pattern to be inspected, and if the pattern size is large, the gap can be widened. When it is small, the gap is also narrowed.

  In addition, when the pattern size is very small, a coating is formed on the electrode surface with an insulating material so that the pattern and the electrode are not in direct contact, and the sensor unit 20 or the inspection signal supply unit is interposed via the insulating material. By controlling 30 so that the gap is almost the thickness of the insulating material by directly attaching 30 to the substrate, the distance between the pattern to be inspected and the electrode can be easily and accurately set to a constant distance.

  Thereby, even a very fine pattern can be obtained with an easy and accurate inspection result with a simple structure. In subsequent step S5, the signal supply unit 65 is instructed to start supplying the inspection signal to the supply electrode 35 of the inspection supply unit 30.

  In step S7, the distance between the pattern and the electrode is kept constant, and the electrodes 25 and 35 of the sensor unit 20 and the inspection signal supply unit 30 are synchronized to cross the inspection target pattern. Control to move while starting to keep the separation distance constant is started. As a result, the sensor electrode 25 subsequently detects the signal potential from the inspection target pattern supplied with the inspection signal by capacitive coupling with the supply electrode 35.

  That is, when the supply electrode 35 is at the position of the pattern to which the inspection signal is supplied, at least a part of the sensor electrode 25 is at the other end position of the inspection target pattern to which the inspection signal is supplied. The sensor electrode 25 at the other end is also controlled to move by one pitch of the inspection target pattern while moving by one pitch of the inspection target pattern at one end.

  For this reason, the signal processing circuit 50 is activated in step S <b> 10, and control is performed so that the detection signal from the sensor electrode 25 is processed and output to the control unit 60. In the signal processing circuit 50, as described above, the detection signal from the sensor electrode 25 of the sensor unit 20 is amplified to a necessary level by the amplifier 51, and the detection signal amplified by the amplifier 51 is passed through the signal of the inspection signal frequency. The noise component is removed by sending it to the filter 52, and then the signal from the bandpass filter 52 is full-wave rectified by the rectifier circuit 53, and the full-wave rectified detection signal is smoothed by the smoothing circuit 54. The data is sent to the D conversion unit 64.

  The CPU 61 activates the A / D conversion unit 64 to convert an input analog signal into a corresponding digital signal, and reads a detection signal detected by the sensor electrode 25 as a digital value. In subsequent step S <b> 12, the CPU 61 sends the read detection signal to the RAM 63. The RAM 63 sequentially stores the detection signals sent. The read detection signal includes all of the detection signal from the normal inspection target pattern, the detection signal from the disconnected inspection target pattern, and the detection signal from the adjacent inspection target pattern short-circuited with the inspection target pattern. .

  In step S14, it is determined whether or not the inspection of the inspection target pattern is completed, for example, whether or not the sensor electrode 25 has moved to a position beyond the last pattern of the inspection target pattern (inspection of the inspection target pattern is performed). Find out if finished).

  If the inspection has been completed only halfway through the inspection target pattern, the process proceeds to step S16, and the scanning of the electrodes is continued to supply the inspection signal to the next pattern. Then, the process returns to step S10, and the reading process is continued. On the other hand, in step S14, when inspection for all the inspection target patterns is completed, the process proceeds to step S20, where the signal supply unit 65 is instructed to stop supplying the inspection signal, and the signal processing circuit 50, A / D conversion is performed. The operation of the unit 64 is stopped.

Finally, in step S22, the inspection object is removed from the inspection position, positioned and conveyed to the next conveyance position, and necessary post-processing is performed.
By controlling as described above, it is possible to inspect the pattern without causing both the sensor electrode 25 and the supply electrode 35 to contact the inspection target pattern at all. For this reason, even if it is a board | substrate with a small intensity | strength of a test object pattern, it can test | inspect, without producing problems, such as scratching a test object pattern.

  For this reason, even if it is the glass substrate for liquid crystal display panels used for the liquid crystal display panel for small mobile phones in which pattern intensity cannot fully be taken, it can test | inspect reliably, without damaging a wiring pattern.

  Further, in the conductive pattern inspection control of the present embodiment, an AC sine wave signal that is a continuous signal is supplied from the supply electrode 35 while the sensor electrode 25 and the supply electrode 35 are moved across the inspection target pattern. Since the signal potential from the pattern to be inspected is supplied to the pattern and detected by the sensor electrode 25, the detection signal, which is the signal potential obtained from the sensor electrode 25, is detected as a certain continuous detection signal value.

  For this reason, when there is a defect inspection target pattern that is open (disconnected inspection target pattern) or short (inspection target pattern short-circuited with the adjacent inspection target pattern) among the plurality of inspection target patterns provided on the inspection target substrate. Between a certain continuous detection signal value that is detected in a continuous range of normal inspection target patterns without open or short, and a defect detection signal value that is detected at a defective inspection target pattern position that has an open or short There is a numerical difference.

  As described above, since the detection signal value of failure due to open or short appears in a certain range of continuous detection signal values as a numerical difference, that is, a change in the numerical value, for example, the detection signal detection result will be described in detail later. 4 and FIG. 4, it is possible to easily determine the defect of the inspection target substrate and to specify the defect inspection target pattern position where there is an open or short.

  Furthermore, the inspection apparatus changes each time the inspection target substrate is inspected while changing the inspection target substrate, due to a change in the gap between the sensor electrode 25 and the inspection target pattern, a change in the gap between the supply electrode 35 and the inspection target pattern, etc. A continuous detection signal value that is constant to some extent becomes a different value as an absolute value every time the substrate to be inspected is changed.

  However, the inspection of the conductive pattern in this embodiment determines the defect of the inspection target substrate and specifies the position of the defect inspection target pattern having an open or short. It is possible to use a numerical difference between detection signal values of defects due to a short circuit, that is, a change in relative numerical values of detection signals.

  For this reason, relative values such as the ratio of the defect detection signal value to the continuous detection signal value and the ratio of the change in the defect detection signal value can be used as a threshold for determining the defect and specifying the defect position. Even if the detection signal value that is constant to a certain degree as an absolute value is not used, even if the inspection apparatus inspects the substrate to be inspected sequentially, it is possible to reliably determine the defect and specify the defect position.

  The inspection control of the conductive pattern of the present embodiment is not limited to the above example, and the detection signal read in step S12 is the threshold value based on the above relative value between step S12 and step S14. If the detection result is within the threshold range, the process proceeds to step S14. If the detection result is not within the threshold range, the inspection target pattern supplying the inspection signal is an open or shorted defect inspection target pattern. There may be provided a step of determining that there is a position and storing the position and state of the inspection target pattern.

  The inspection signal detection result by the sensor electrode 25 by the above control is shown in FIGS. FIG. 3 is a diagram illustrating an example of inspection signal detection when three inspection target patterns in the inspection apparatus according to the present embodiment are disconnected (opened), and FIG. 4 is a diagram illustrating one inspection target pattern according to the present exemplary embodiment. It is a figure which shows the example of a test | inspection signal detection at the time of short-circuiting (short-circuiting) in the middle.

When the inspection target pattern is normal, the inspection signal (AC signal) supplied from the signal supply unit 65 to the supply electrode 35 is supplied to the inspection target pattern that is capacitively coupled, and the inspection target pattern is passed through the inspection target pattern. It reaches the lower part of the sensor electrode 25, is detected by the sensor electrode 25 by capacitive coupling with the sensor electrode 25, and is output to the control unit 60.
As described above, the supply electrode 35 and the sensor electrode 25 supply and detect the inspection signal (alternating current signal) while traversing the inspection target pattern, so that the detection signal is continuously detected as a detection signal value that is constant to some extent.

  When at least a part of the inspection target pattern is disconnected, at least a part of the inspection signal (AC power) supplied from the signal supply unit 65 to the supply electrode 35 is on the sensor electrode 25 side by the disconnection part of the inspection target pattern. Therefore, the detection signal value becomes small. For this reason, as shown in FIG. 3, the detection signal value of the disconnected inspection target pattern portion is smaller than a continuous constant value detected from a normal inspection target pattern.

  On the other hand, when the inspection target pattern is short-circuited with the adjacent inspection target pattern, the inspection signal (AC power) supplied from the signal supply unit 65 to the supply electrode 35 is adjacent through the short-circuit portion with the adjacent inspection target pattern. Since it also flows in the inspection target pattern, the detection signal from the sensor electrode 25 is superimposed on the detection signal of the adjacent inspection target pattern, and the detection signal value increases. Therefore, as shown in FIG. 4, the detection signal value of the shorted inspection target pattern portion is larger than the continuous constant value detected from the normal inspection target pattern.

  The reason why disconnection and short-circuiting of the detection target pattern as described above can be performed by one sensor electrode 25 is that the width of the sensor electrode 25 is set to be wider by at least one pitch of the inspection target pattern than the width of the supply electrode 35. Because. However, the width of the sensor electrode 25 does not necessarily have to be one pitch or more of the inspection target pattern than the width of the supply electrode 35, but the inspection target pattern that is disconnected or the inspection target pattern that is short-circuited with the adjacent inspection target pattern is not necessarily included. For example, the configuration of the second embodiment whose details will be described later may be used.

  At this time, if a threshold value is set within a certain range to a certain fixed continuous detection signal value as an absolute value, if the detection signal value is smaller than the threshold value, the inspection target pattern is disconnected, and the detection signal value is lower than the threshold value. If it is larger, it can be determined that the inspection target pattern is short-circuited. For example, in FIG. 4, if the threshold value is 0.02 Vpp for a continuous detection signal value of 0.60 Vpp, which is constant to some extent, the sensor moving distance is about 22 mm, 42 mm, and 78 mm that is 0.58 Vpp or less. It is determined that the inspection target pattern is disconnected.

  Further, as a threshold for determining a defect or specifying a defect position, for example, using a relative value such as a ratio of a defect detection signal value to a continuous detection signal value or a ratio of a change in defect detection signal value, for example, continuous When the detected signal value decreases by 3% or more, it can be determined that the inspection target pattern is disconnected, and when the continuous detection signal value increases by 3% or more, it can be determined that the inspection target pattern is short-circuited.

  As described above, in the present embodiment, the absolute value can be used as a threshold value for determining the quality of the pattern, and the relative change rate of the detection signal value of the defective pattern with respect to the detection signal value of the normal pattern is expressed as follows. Since it can be used as a threshold value, an optimum threshold value can be set according to the detection result even if the inspection device inspects the substrate to be inspected sequentially. Even if the detection signal value varies from inspection to inspection, the detection signal Even when the value is low, these effects can be completely prevented, and an accurate test result can be obtained.

  As described above, even when the inspection method in which the detection signal value is small because both the sensor unit and the inspection signal supply unit are non-contact, the difference can be obtained by using the inspection device of this embodiment. Can be reliably recognized, and the pattern state can be inspected easily and reliably.

  For this reason, it is possible to detect the quality of the pattern very accurately and easily compared to the conventional method of determining the quality using the absolute value of the detection signal value as a threshold value. In addition, since it is non-contact, accurate positioning accuracy is unnecessary, and even a substrate with a very fine pattern pitch to be inspected can be inspected with high accuracy.

[Embodiment of the Second Invention]
In the above description, an example has been described in which at least a part of the sensor electrode 25 is always controlled so that the supply electrode 35 is positioned at the other end of the pattern that is actually supplying the inspection signal. However, the present invention is not limited to the above example. For example, a plurality of sensor electrodes 25 are provided, and one of the plurality of sensor electrodes 25 is actually supplied with the inspection signal by the supply electrode 35. Provided so as to be at the other end position of the pattern, and at least one of the plurality of sensor electrodes 25 provided at the other end position of the pattern adjacent to the pattern to which the supply electrode 35 actually supplies the inspection signal It may be configured.

A second embodiment of the present invention configured as described above will be described below with reference to FIG. FIG. 5 is a diagram for explaining the configuration of the inspection apparatus according to the second embodiment of the present invention. In FIG. 5, the same components as those shown in FIG. 1 of the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.
In FIG. 5, a first sensor electrode 22 and a second sensor electrode 24 are provided on at least the tip surface of the sensor unit 20. The first sensor electrode 22 and the second sensor electrode 24 are spaced apart from each other by the pattern pitch of the pattern to be inspected, and the first sensor electrode 22 is supplied by the supply electrode 35 that actually supplies the inspection signal. The second sensor electrode 24 is provided at the other end position of the received inspection target pattern, and the other end of the adjacent inspection target pattern adjacent to the received inspection target pattern to which the supply electrode 35 actually supplies the inspection signal. It is provided in a state offset to the part position.

  The widths of the first sensor electrode 22 and the second sensor electrode 24 are preferably set to be equal to or smaller than the pattern width of the inspection target pattern. This is because the first sensor electrode 22 inspects the disconnection of the receiving inspection object pattern, and the second sensor electrode 24 inspects the short circuit between the receiving inspection object pattern and the adjacent inspection object pattern. This is to realize a high inspection.

  Specifically, when the width of the first sensor electrode 22 is equal to or smaller than the pattern width of the inspection target pattern, the received inspection target pattern is disconnected, and the received inspection target pattern and the adjacent inspection target pattern are short-circuited. Even if it is a case, the 1st sensor electrode 22 becomes difficult to receive to the influence of the detection signal from the inspection signal from the adjacent inspection object pattern which flowed into the adjacent inspection object pattern through the short circuit part from the received inspection object pattern. Further, when the width of the second sensor electrode 24 is equal to or smaller than the pattern width of the inspection target pattern, the inspection target pattern has no disconnection or short circuit, or the received inspection target pattern has no disconnection, but the received inspection target pattern and the adjacent inspection Even if the target pattern is short-circuited, the second sensor electrode 24 is less susceptible to the inspection signal from the received inspection target pattern.

  Thus, in the inspection of the disconnection / short circuit by the first sensor electrode 22 and the second sensor electrode 24, how the presence / absence of the disconnection of the receiving inspection object pattern and the presence / absence of the short circuit of the adjacent inspection object pattern exists. However, it is possible to realize a highly accurate inspection. However, it is apparent from the sensor electrode 25 in the first embodiment that the widths of the first sensor electrode 22 and the second sensor electrode 24 are not necessarily equal to or smaller than the pattern width of the inspection target pattern.

  Furthermore, in the second embodiment described in detail above, the offset sensor electrode is described as the second sensor electrode 24, but it is opposite to the adjacent inspection target pattern adjacent to the received inspection target pattern. By detecting the inspection signal from the second adjacent inspection target pattern adjacent on the side, a third sensor electrode is provided to simultaneously inspect a short circuit between two adjacent inspection target patterns adjacent to both sides of the power reception inspection target pattern. It is also possible to do.

  In addition, the sensor electrode provided in the sensor unit 20 may have no problem with only the first sensor electrode 22 or the second sensor electrode 24, or may be provided with three or more offset sensor electrodes. Needless to say.

[Embodiment Example of Third Invention]
In the above description, an example in which a defective pattern is detected by moving the sensor electrode 25 and the supply electrode 35 so as to cross the end portion of the inspection target pattern has been described. However, the present invention is not limited to the above example. For example, one of the sensor electrode 25 and the supply electrode 35 can be moved and controlled along the pattern to be inspected, and the defective pattern is identified by the above-described control. After that, both electrodes are positioned at the defective pattern position, one electrode is moved on the pattern along the defective pattern, the detection signal value at the sensor electrode 25 is read, and the change position of the detection signal value is detected to detect the pattern defect. You may comprise so that an occurrence location can be specified.

  A second embodiment of the present invention configured as described above will be described below with reference to FIGS. FIG. 6 is an inspection apparatus according to the second embodiment of the present invention, FIG. 7 is a diagram for explaining electrode movement control in the inspection apparatus of the second embodiment according to the present invention, and FIG. 9 is a flowchart for explaining pattern defect location specifying control according to the second embodiment, FIG. 9 is a diagram showing an example of a defect pattern detection signal waveform at the sensor electrode 25 in the second embodiment apparatus, and FIG. It is a figure which shows the example of the detection signal waveform of the sensor electrode 25 in a defect pattern.

In FIG. 6, the same components as those shown in FIG. 1 of the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.
In FIG. 6, a camera 26 is attached to the detection unit 20. The camera 26 is connected to, for example, the display unit 66 of the control unit 60 in order to display the captured video, and is used to observe the defect occurrence state at the pattern defect occurrence location. The inspection signal supply unit 30 is provided with probe contact means 32 to which an inspection signal supply probe for supplying an inspection signal is attached. The probe contact means 32 and the inspection signal supply probe are used for surely specifying the pattern defect occurrence location.

In the second embodiment, the scalar robot is configured not only to move in the direction of the arrow in FIG. 1 but also to control the movement of the electrode in the pattern longitudinal direction in FIG.
First, the inspection control shown in FIG. 2 of the first embodiment described above is performed to inspect whether there is a defect in the inspection target pattern. As a result of the inspection, for example, the inspection target pattern position of the inspection target pattern determined to be a pattern disconnection is held in, for example, the RAM 63.

  When the defective pattern is detected in this way and the defective pattern position is specified, the process proceeds to a defective portion specifying process. In the defect location specifying process of the second embodiment, as indicated by a circle 1 in FIG. 7, first, the supply electrode 35 and the sensor electrode 25 are synchronized and moved to a pattern position determined to be defective.

  Subsequently, as indicated by a circle 2 in FIG. 7, the inspection signal is sequentially read while moving the sensor electrode 25 from the pattern end to the other end, and the position where the read signal changes rapidly (the detection signal is not detected. Alternatively, a position that changes to a low level) is obtained, and the position is specified as a pattern defect location.

  Hereinafter, this will be described in detail with reference to the flowchart of FIG. In the second embodiment, following the process of step S14 in the first embodiment described above, the detection signal stored in the RAM 63 is checked to determine whether a defective pattern has been detected. If no pattern is detected, the process proceeds to step S20.

  On the other hand, when a defective pattern is detected as a result of the inspection, the signal supply unit 65 is turned off, and the electrode is positioned at the initial position as in step S3, and the process proceeds to the process shown in FIG. And what is necessary is just to transfer to the process of step S20 after completion | finish of the process shown in FIG.

  In the second embodiment, first, as shown in step S31 of FIG. 8, the defective pattern position detected by the processing of steps S1 to S16 shown in FIG. 2 is specified. For example, FIG. 9 shows a detection signal waveform when a part of the pattern is disconnected. In the example shown in FIG. 9, the signal before the signal processing in the analog signal processing circuit 50 is shown. A portion indicated by a circle is a signal waveform detected as a pattern open (when two patterns are disconnected).

  Subsequently, in step S33, the robot controller 70 is activated, the scalar robot 80 is controlled, and the sensor electrode 25 and the supply electrode 35 are moved to the defective pattern position while being synchronized with each other. At this time, in order to perform detection with high sensitivity, the sensor electrode 25 and the supply electrode 35 are positioned so that the centers of the width direction of the sensor electrode 25 and the supply electrode 35 are substantially centered in the width direction of the defective pattern (control 1 in FIG. 7).

  In step S35, the signal supply unit 65 is activated to apply an inspection signal to the supply electrode 35 to supply the inspection signal to the defective pattern. Then, the robot controller 70 is activated to move the sensor electrode 25 in the direction of the supply electrode 35 along the pattern (control of circle 2 in FIG. 7).

  At the same time, the detection signal from the sensor electrode 25 is read as shown in step S40. In subsequent step S42, it is checked whether or not the detection signal value from the sensor electrode 25 has changed greatly. If not significantly changed, the process returns to step S37 to continue the movement of the sensor electrode 25. On the other hand, when the detection signal value from the sensor electrode 25 changes greatly in step S42, the process proceeds to change step S44, where the detection signal from the sensor electrode 25 starts to change greatly and the position where the change does not change greatly. The intermediate position between these positions is determined as a pattern defect location.

  An example of the detection signal waveform at the sensor electrode 25 is shown in FIG. As shown in FIG. 10, the inspection signal supplied from the supply electrode 35 has not reached the sensor electrode 25 until the disconnection point, and the detection signal value is low. Since it reaches, the detection signal value rises. For example, the intermediate position between the position where the detection signal from the sensor electrode 25 starts to change greatly and the position where the change no longer occurs is specified as a pattern defect location. Identified as a location. In the above description, the sensor electrode 25 is moved in the direction of the supply electrode. However, instead of the sensor electrode 25, the supply electrode 35 may be moved in the direction of the sensor electrode 25.

  As described above, according to the second embodiment, it is possible to perform non-contact pattern inspection with high accuracy in the same manner as in the first embodiment described above, and to connect the sensor electrode to X By controlling the movement in the two directions of −Y, it is possible not only to check whether there is a defective pattern, but also to specify a specific defective portion. For this reason, for example, it is possible to repair a defective portion in a short time if necessary.

  Further, in order to determine whether or not repair is possible in the repair of the above-described defective portion, it is desirable to be able to observe the defect occurrence state at the pattern defect occurrence portion. For example, if it is found that only dust or the like is attached to the pattern defect occurrence location, it can be determined that the repair is possible on the spot, and if it is a fatal defect, it is determined that the repair is not performed. be able to.

  The camera 26 attached to the detection unit 20 is used for observing the defect occurrence state at the pattern defect occurrence location. Since the camera 26 is attached to the detection unit 20, the camera 26 starts shooting in step S35, and continues shooting while steps S40 and S42 are performed, and the pattern defect in step S42. Continue shooting until after the location is identified. The image of the pattern defect occurrence location photographed in this way is displayed on the display unit 66 while the imaging is continued and after the pattern defect occurrence location is specified, and is used for observing the defect occurrence state of the pattern defect occurrence location. .

Moreover, the state of the defective portion of the pattern varies from a complete disconnection or short circuit state to a partial disconnection or partial short circuit state due to deposits such as dust. In a partially broken or partially shorted state, a detection signal waveform as shown in FIG. 10 may not be obtained in an inspection in which both the sensor electrode 25 and the supply electrode 35 are not in contact. In such a case, if the probe contact means 32 is operated to bring the inspection signal supply probe into contact with one end of the defective pattern and then the sensor electrode 25 is moved along the defective pattern, the pattern is surely obtained. It is possible to identify a defect occurrence location.
Note that a contact-type sensor probe is used instead of the sensor electrode 25 at the other end of the defective pattern, and the sensor probe is brought into contact with the other end to connect the non-contact supply electrode 35 to the sensor at the other end of the defective pattern. It may be moved in the probe direction.

[Embodiment of Fourth Embodiment]
In the above description, an example in which the movement control of the sensor electrode 25 and the supply electrode 35 is two-dimensionally controlled mainly in the XY directions by the scalar robot 80 has been described. This is because the substrate to be inspected is a liquid crystal panel, and the glass substrate is highly smooth. When inspecting a substrate where the pattern thickness is large or the inspection substrate is large and the surface unevenness is not avoided, not only the above two-dimensional control but also the vertical direction (Z direction) should be controlled. What is necessary is just to comprise so that a test result can be obtained even if there exists an unevenness | corrugation of a board | substrate to be inspected.

  A third embodiment according to the present invention configured to control not only in the two-dimensional control but also in the vertical direction (Z direction) will be described below with reference to FIG. FIG. 11 is a diagram for explaining the configuration of the inspection apparatus according to the third embodiment of the present invention. In FIG. 11, the same reference numerals are given to the same components as those shown in FIG. 1 of the first embodiment described above, and detailed description thereof is omitted.

In FIG. 11, a laser displacement meter 28 is attached to the detection unit 20, and a laser displacement meter 38 is attached to the inspection signal supply unit 30, and the detection unit 20, inspection signal is detected from the detection results from both displacement meters 28, 38. A distance measuring unit 90 that measures the distance between the supply unit 30 and the surface of the substrate to be inspected is provided.
Further, the scalar robot 80 is configured to be capable of two-dimensional control of the detection unit 20 and the inspection signal supply unit 30 and also capable of positioning control in a direction (vertical direction) orthogonal to the drawing.
In the third embodiment having the above configuration, the distance measuring unit 90 activates the laser displacement meters 28 and 38 simultaneously with the movement of the electrodes, and measures the distance between each electrode and the surface of the substrate to be inspected. The measurement result is output to the control unit 60.

In addition, the control unit 60 averages the measurement result of the measurement distance while the electrode moves from the distance measurement unit 90 by a certain distance, and controls the distance between the electrode and the pattern so that the averaged distance becomes constant. Yes. For example, the distance between the electrode and the substrate surface is controlled according to the average of the distances of three patterns to be inspected.
The reason for averaging the distance in this way is to prevent abrupt Z-direction control to be gentle control and to reduce the influence of noise, measurement error, and the like.

  Performing not only the X-Y direction but also the Z direction control in this way is particularly effective for inspection of a large substrate. For example, in the inspection of a pattern to be inspected on the surface of a large flat display panel, the curvature of the surface of the substrate is inevitably avoided, and even in such a case, the electrode and the pattern can be effectively prevented from contacting each other.

  When the pattern is thick, the measurement distance to be averaged may be narrowed to enable detection with higher sensitivity.

It is a figure for demonstrating the pattern test | inspection principle of one embodiment of one invention concerning this invention. It is a flowchart for demonstrating the test | inspection control of the test | inspection apparatus which is this embodiment. It is a figure which shows the example of a detection signal when the adjacent test object pattern is short-circuited (short-circuited) in the test | inspection apparatus which is this Embodiment. It is a figure which shows the example of a detection waveform in case one of the test object patterns in the test | inspection apparatus which is this embodiment is a disconnection (open) state on the way. It is a figure which shows the structure of the inspection apparatus of the 2nd Embodiment based on this invention. It is a figure which shows the structure of the test | inspection apparatus of the 3rd Embodiment based on this invention. It is a figure for demonstrating the electrode movement control in the inspection apparatus of the example of 3rd Embodiment. It is a flowchart for demonstrating pattern defect location specific control of the 3rd Embodiment. It is a figure which shows the example of the defect pattern detection signal waveform in the sensor electrode in the apparatus of the example of 3rd Embodiment. It is a figure which shows the example of the detection signal waveform of the sensor electrode in a defect pattern. It is a figure for demonstrating the structure of the inspection apparatus of the 4th Embodiment based on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Glass substrate, 15 ... Conductive pattern, 20 ... Sensor part, 22 ... First sensor electrode, 24 ... Second sensor electrode, 25 ... Sensor electrode, 26 ... Camera, 28 ... Laser displacement meter, 30 ... Inspection Signal supply section 32 ... probe contact means 35 ... supply electrode 38 ... laser displacement meter 50 ... analog signal processing circuit 51 ... amplifier 52 ... band pass filter 53 ... rectifier circuit 54 ... smoothing circuit 60 ... Control unit, 70 ... robot controller, 80 ... scalar robot, 61 ... CPU, 62 ... ROM, 63 ... RAM, 64 ... A / D converter, 65 ... signal supply unit, 66 ... display unit.

Claims (14)

An AC inspection signal is supplied to one inspection target pattern among a plurality of conductive patterns formed in a substantially bar shape with a predetermined width in the inspection target region and in the vicinity of both ends, and a signal is transmitted from the inspection target pattern. A circuit pattern inspection apparatus for detecting and inspecting the inspection target pattern,
Supply means having a supply electrode for supplying the inspection signal to one end of the inspection target pattern;
Detection means having at least two detection electrodes that are respectively capacitively coupled to the inspection target pattern to which the inspection signal is supplied and a pattern adjacent to the inspection target pattern to which the inspection signal is supplied;
The supply electrode and the detection electrode are mounted on the respective movable support members, and are separated from the inspection target pattern, and in order to capacitively couple the inspection target patterns facing each other, the both ends of the inspection target pattern A first moving means for moving across
The first moving unit moves in synchronization so that the supply electrode and the detection electrode pass above one end and the other end of the same inspection target pattern, and the detection unit includes the inspection target pattern and the adjacent region. A circuit pattern inspection apparatus for detecting a defect due to a disconnection or a short circuit of the inspection target pattern from the inspection signal obtained by a change in the capacitive coupling in a pattern to be performed.   Further, when the detection result by the detection unit is within a predetermined range, the determination unit determines that the inspection target pattern is normal, and when the detection result is out of the predetermined range, it is determined that the inspection target pattern is defective. The circuit pattern inspection apparatus according to claim 1, further comprising: Furthermore, when the supply electrode and the detection electrode are opposed to the both ends of the inspection target pattern determined by the determination unit as opposed to the first movement unit, the supply electrode and the detection electrode A second moving means for fixing one of the two and moving the other along the inspection target pattern;
Position detection means for detecting a detection change position in the inspection target pattern based on a detection result of the detection means;
The circuit pattern inspection apparatus according to claim 2, further comprising: detecting a location of the defect.   The circuit pattern inspection apparatus according to claim 3, further comprising an imaging unit mounted on the moving support member.   The apparatus further comprises a separation control unit that performs positioning control so that a distance between at least one of the supply electrode and the detection electrode moved by the second moving unit and the inspection target pattern is substantially constant. 3. The circuit pattern inspection apparatus according to 3.   A separation distance control unit that performs positioning control so that a separation distance between at least one of the supply electrode and the detection electrode moved by the first movement unit and the inspection target pattern is substantially constant is provided. The circuit pattern inspection apparatus according to claim 1.   The separation processing control means includes a displacement meter that moves together with the detection electrode or the supply electrode at a position near the detection electrode or the supply electrode, and separates the detection electrode or the supply electrode from the inspection object according to the detection result of the displacement meter. 7. The circuit pattern inspection apparatus according to claim 5, wherein positioning control is performed in a direction orthogonal to the inspection object so that the distance is substantially constant.   The separation processing control means positions an average displacement of detection results of the displacement meter between a plurality of pitches of the inspection object pattern in a direction orthogonal to the inspection object as a separation distance between the detection electrode or the supply electrode and the inspection object. The circuit pattern inspection apparatus according to claim 7, wherein the circuit pattern inspection apparatus is controlled. A supply means having a supply electrode for supplying an AC inspection signal to one inspection target pattern among a plurality of conductive patterns formed in a substantially bar shape with a predetermined width in the inspection target region and in the vicinity of both ends; and Detection means having detection electrodes for detecting respective signals simultaneously and individually from the inspection target pattern and a pattern adjacent to the inspection target pattern ;
A pattern inspection method in a circuit pattern inspection apparatus for inspecting the quality of the inspection target pattern,
The inspection signal is supplied to the inspection target pattern separated from the supply electrode, and the detection means separates at least two columns of the inspection target pattern and a pattern adjacent to the inspection target pattern and performs capacitive coupling individually. And
While maintaining the capacitive coupling state, the supply electrode and the detection electrode move synchronously so as to pass above one end and the other end of the same inspection target pattern,
A circuit pattern inspection method for detecting a defect due to disconnection or short circuit of the inspection target pattern from the inspection signal obtained by the change of the capacitive coupling in the inspection target pattern and the adjacent pattern.   Further, when the detection result by the detection means is within a predetermined range, the normality of the inspection target pattern is determined, and when the detection result is out of the predetermined range, the defect of the inspection target pattern is determined. The circuit pattern inspection method according to claim 9.   When the supply electrode and the detection electrode are opposed to both ends of an inspection target pattern determined to be defective by the pattern inspection method, either the supply unit or the detection unit is fixed, and the other is The circuit pattern inspection method according to claim 9, wherein the position of a defect in the inspection target pattern is detected based on a result detected by the detection unit by moving along the inspection target pattern.   The imaging means provided on either one of the movement support members that mount and move the supply electrode and the detection electrode are moved along the pattern toward the other, and the defective state of the defective position of the inspection target pattern is determined. The circuit pattern inspection method according to claim 11, wherein imaging is performed.   When the detection unit or the supply unit moves, the displacement of the separation distance between the detection electrode or the supply electrode and the inspection target pattern is detected, and positioning control is performed so that the detected separation distance becomes substantially constant. 13. The circuit pattern inspection method according to claim 9, wherein a result of the detection electrode is made constant.   12. The circuit according to claim 11, wherein positioning control with respect to the inspection object is performed by setting an average displacement of the displacements between the plurality of pitches of the inspection object pattern as a separation distance between the detection electrode or the supply electrode and the inspection object. Pattern inspection method.

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