JPH023299A - Laser repair device - Google Patents

Abstract

PURPOSE:To make it possible to prevent slippage of the position of irradiation by according the light axis of laser beams and the light axis of a repair monitor camera with each other. CONSTITUTION:In a laser repair unit 50, the laser beams issued from a laser oscillator 51 are reflected at a right angle at a reflection mirror 54, and are reflected by a beam splitter 57 arranged on the light axis of a camera 60, and are irradiated onto an LCD 10 through an object lens 58 arranged on the same light axis. The light of an illumination lamp 61 inside the unit 50 is reflected by the LCD 10, and are made into the image at the camera 60 through the lens 58, the beam splitter 57 and the magnification lens system, whereby it becomes possible to collect image information that a part on the LCD 10 is magnified. Hereby, if the defective patter position is set according to the image information of the camera 60, this surely accords with a laser spot position, thus laser repair can be performed accurately without dislocation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a laser repair device for LCD (liquid crystal display) boards, printed circuit boards, etc.

(Prior Art) In recent years, with the miniaturization of electronic devices, the patterns of circuit boards have become denser, and the need for LCDs as display panels has increased.

For example, if we take an LCD as an example, this type of LCD
Before filling the liquid crystal into the liquid crystal drive element, for example, the TP
T electrical function test or short circuit between horizontal scanning lines and vertical signal lines formed in a matrix or their intersections.

Oven inspection etc. have become essential.

For this reason, conventionally, inspection equipment has been provided in which a tester is connected to an LCD probe device, and this inspection equipment performs an inspection of the electrical characteristics of the LCD, and repairs the paste bearing information such as the location of the defect and the details of the defect. The information is transmitted to the device (also referred to as a rescue device) to repair pattern shorts, opens, etc.

Here, glue bears such as pattern shorts can be made by irradiating laser light onto the short-circuited parts and laser-cutting these parts.

By the way, in order to perform laser cutting in this way, it is necessary to ensure that the laser spot is set on the defective pattern, so a monitor camera such as a COD camera is placed separately from the laser source, and this monitor camera is placed in advance. It was necessary to take a photograph of the vicinity of the defective pattern, display it on a monitor, and align the laser spot with the defective pattern.

(Problem to be solved by the invention) As mentioned above, in order to perform laser repair,
A camera for monitoring or alignment is essential, but in the past, even if the laser spot position was set on the defective pattern photographed and displayed by the camera, the actual position of the irradiated laser did not accurately capture the defective pattern. There were cases where this was not possible.

Conventionally, the laser irradiation optical axis of the laser source and the incident optical axis of the light that is imaged on the camera are placed separately, so even if the defective pattern position is aligned based on camera information, it will not match the laser spot. That wasn't necessarily the case.

Therefore, the purpose of the present invention is to solve the above-mentioned conventional problems, and by setting the position of the defective pattern according to the photographing information of the camera, it will surely match the position of the laser spot, so that it will be accurately positioned without any misalignment. The purpose of the present invention is to provide a laser repair device capable of performing laser repair.

[Structure of the Invention (Means for Solving Problems)] The present invention comprises a laser source for irradiating a laser beam onto a defective pattern on a board to be repaired, and a camera for alignment or monitor display of this board. In a laser repair device that repairs the defective pattern by irradiating laser light after aligning the defective pattern to the laser spot position based on the photographic information of the camera, the optical axis of the laser source and the camera board are coaxial. The structure is as follows.

(Function) In this type of laser repair device, first, at the initial stage, a laser beam is irradiated onto a stage on which a substrate is placed and supported, and the laser beam is photographed by a camera and a laser spot is displayed on a monitor.

Then, for example, the intersection of two orthogonal axes of cursors displayed superimposed on the monitor is made to coincide with this beam spot, and this cursor intersection is fixed as the beam spot.

Next, the board is set on the stage, this board is photographed with a camera and displayed on a monitor, and the stage is fine-aligned so that the defective pattern displayed on the monitor matches the intersection of the cursors above. .

Here, if the optical axis of the laser light source and the camera board match, the laser spot displayed on the monitor at the initial time will accurately reflect the laser spot that is the actual position of the laser light source, and therefore If the defective pattern is positioned so as to coincide with the laser spot, then this defective pattern is reliably set at the laser spot position.

After setting in this manner, if the laser light source is driven to irradiate laser light, the defective pattern is accurately irradiated with laser light, and repair can be reliably performed.

Further, by aligning the optical axes in this manner, the optical system for the laser light source and the optical system for the camera can be partially used in common, thereby making it possible to reduce the size and cost of the apparatus.

(Example) Hereinafter, an example in which the present invention is applied to an inspection/repair device for an LCD board will be specifically described with reference to the drawings.

As shown in FIG. 1, this LCD board inspection/repair device includes a loader device 1 placed on the right side of the casing, and a loader device 1 placed on the left side of the loader device 1 on the front side of the casing. It consists of a probe device 2 and a laser repair device W3 placed behind it, an operation panel 4 for the probe device on the front side of the probe device 2, and an operation panel 4 for the laser repair device on the left side of the housing. An operation panel 5 is arranged behind the control panel 5, and a monitor TV 6 is arranged behind it.

The loader device 1 includes an LCD housed in a carrier cassette.
The substrates are taken out one by one and supplied to the probe device 2, and the inspected, repaired, or re-inspected LCDs carried out from the probe device 2 are returned to the carrier cassette and transported.

In this embodiment, the probe device 2 is used to measure the scanning line of the LCD board, the oven of the signal line, the short circuit between each line, and the insulation resistance value of the line intersection, and for this purpose, as shown in FIG. Four probe boards are arranged so as to be able to contact each of the electrode regions 11, 12, 13, and 14 arranged on the four sides of the LCD l0.

Here, electrode areas 11 and 12 are scan line lead electrodes and signal line lead electrodes, respectively, and electrode areas 13 and 13 are respectively scan line lead electrodes and signal line lead electrodes.
14 are electrodes opposite to the electrode areas 11 and 12, respectively.

In this embodiment, as a probe board for the electrode areas 11 and 12, one end of the flexible film electrode 20 is curled, as shown in FIG.
1, and a flexible member such as felt 22 is interposed between the electrode structure and the film electrode f! 21 in the electrode region 11.
The electrical connection is made by press-contacting each of the 12 electrodes.

On the other hand, as shown in FIG. 3(B), the probe board used for the electrode areas 13 and 14 of the counter electrode is
A large number of probe needles 26 are fixed to the probe 5, and the tips of the needles 26 are bent so as to be able to contact each electrode in the electrode areas 13 and 14. The reason why two types of probe boards are used is that the electrode areas 13 and 14 of the counter electrode are provided only for this type of inspection, and the LC
Since the pad space is limited due to the high density of D10, conduction is ensured by the probe needle 26 that can reliably make contact even in a small space.

Further, this counter electrode is used when inspecting for disconnection of each signal line or scanning line or short circuit between lines, and the number of defects of this kind is relatively small and the requirements for inspection are low. In order to inspect short circuits and disconnections in lines where there is little need, we used the film electrode method in four ways.
If the film electrode were to be used in various locations, it would require a large-scale adjustment mechanism to bring the film electrode into contact with the electrode with uniform pressure over a predetermined width. Therefore, by adopting a probe needle method with a relatively simple support mechanism, costs can be reduced. I'm trying to bring it down.

Each probe board is connected to the tester 3 shown in FIG.
0, and here it is possible to determine whether each line is open or short between lines, the insulation resistance value at the line intersection, etc.

In this probe device 2, the stage 40 on which the LCD 10 is placed and supported is arranged along two axes, X and Y, which are orthogonal to the mounting surface.
The stage is movable in an axis, a Z axis which is a height direction orthogonal to both axes, and a θ direction which is a rotation direction around this Z axis and rotates on the X-Y plane. 4
In addition to the probing position JA in the probe device W2, 0 is the repair point tB where repair is performed in the bare device 3 as described above.
It is also movable. And this stage 40
is controlled by a controller 42.

Further, as a feature of this probe device 2, alignment of the above-mentioned probing position fA''C'' LCD 10 can be executed. That is, the above-mentioned blobbing position HA
A microscope 8 is arranged above as shown in Fig. 1, and an alignment camera 41 such as a COD camera shown in Fig. 4 can be installed by inserting a mount into the eyepiece of this microscope 8. ing. This alignment camera 41 enlarges and photographs a part of the surface of the LCD 10 through the microscope 8, and the photographing information is input to the controller 42 shown in FIG. 4, and an image is displayed on the monitor TV 6 by video switching. It is possible to display.

Then, you can perform alignment by operating the joystick on the operation panel 4 while looking at this screen, or you can use the image pattern described above (for example, a matrix pattern of scanning lines and signal lines) to automate the alignment.
is sent to the controller 42 and compared with the pattern stored in the memory 46 for the normal position, and the alignment drive of the stage 40 can be automatically controlled based on the comparison result.

In this way, by making the probing position and the alignment position common, it is possible to prevent positional deviations caused by mechanical errors in the moving system after alignment is performed at a different location as in the past. The probe position WWI degree can be improved.

Note that the measurement results from the tester 30 are determined by the controller 4.
2, for example, in the memory 46 provided in the probe device 2, and the details of the defect and its address are stored as repair information. Note that this repair information may be stored in a memory within the host CPU 44, which will be described later.

Next, the laser repair device 3 will be explained.

In this embodiment, the stage 4 used in the probe device 2
0 is also shared with repair device 3, and LCDl0 is used as stage 4.
The laser repair unit 50 is movable by the drive of the laser 0, and a laser repair unit 50 is fixed above the laser repair unit 50.

This laser repair unit 50 includes a laser oscillator 51 that emits a laser beam for trimming a short pattern on the LCD 10, and a laser oscillator 51 that emits a laser beam for trimming a short pattern on the LCD 10, and a laser oscillator 51 that emits a laser beam for trimming short patterns on the LCD 10, and a laser oscillator 51 that emits a laser beam for trimming a short pattern on the LCD 10, and a laser oscillator 51 that emits a laser beam for trimming a short pattern on the LCD 10, and a laser oscillator 51 that emits a laser beam for trimming a short pattern on the LCD 10, and a laser oscillator 51 that emits a laser beam for trimming a short pattern on the LCD 10, and a laser oscillator 51 that emits a laser beam for trimming a short pattern on the LCD 10.
A glue pair monitor camera 60 with an autofocus function, such as a CD camera, is provided, and the laser optical axis and the optical axes for alignment and monitoring are configured to coincide above the substrate.

That is, the laser beam emitted from the laser oscillator 51 is passed through the N and D filters 52 . It is reflected at a right angle by a reflection mirror 54 through an aperture 53, and further reflected by a shutter 5.
5 and the repair monitor camera 6 via the lens 56.
The beam is guided to a beam splitter 57 arranged on the optical axis of 0. By being reflected by this beam splitter 57, the laser beam is irradiated onto the LCD l0 via an objective lens 58 arranged on the same optical axis.

On the other hand, an illumination lamp 61 is arranged inside the laser repair unit 50, and the light of this illumination lamp 61 is
reflected by the objective lens 58. An image is formed on a repair monitor camera 60 via a beam splitter 57 and a magnifying lens system, and information on a portion of the enlarged image on the LCD 10 can be collected.

In this way, by aligning the optical axis of the laser beam emitted by the laser oscillator 51 with the optical axis for the repair monitor camera 61, it is possible to reliably irradiate the laser beam to the aligned position, and the black It is possible to prevent the projection position from shifting.

Further, since a part of the optical system can be shared, it is possible to reduce the size and cost of the device.

Note that the laser beam emitted by the laser oscillator 51 is performed in the following manner. That is, a laser cut switch 70 (details will be described later) is provided on the operation panel 5 as shown in FIG.
When pressed, a laser excitation signal is output to the laser power source 62, and the laser power source 62 outputs the laser excitation signal to the laser oscillator 51, thereby emitting a laser beam.

In addition, an illumination lamp 61 inside the laser repair unit 50
The operation panel 5 also operates the operation panel 5, and the lighting switch 71 switches the lamp 61 to 0N10FFL,
Further, the brightness of the lamp 61 can be changed continuously by the illuminance changeover switch 72.

The operation panel 5 is also provided with various switches as shown in FIG. 5 in addition to the switches described above.

Power switch 73...Turns the power of the laser repair device 3 to 0
This is for N10FF.

Cursor movement switch 74 (X-axis, Y-axis): for moving the orthogonal cursor 5a (see FIG. 6) superimposed on the repair pattern displayed on the monitor TV 6. In addition, at the initial time, the laser is irradiated once, and the intersection of the cursor 5a is aligned with the irradiation point 5b displayed on the monitor TV 6, as shown in FIGS. 6(A) and 6(B), and is fixed thereafter. That is, the intersection of the cursors 5a is the laser irradiation position (laser spot)
becomes.

Start switch 75...This is a switch that starts the laser repair device 3, and after cutting the defective pattern,
By pressing this switch, the pattern moves to the next defective pattern.

Stop switch 76: This is a switch that is operated when stopping the laser repair device 3 or interrupting the operation.

Z-axis movement switch 77 This is a switch for moving the stage 4o in the Z direction.

Display 78: Displays information necessary for repair.

Joystick 79... is used to move the pixels of the LCD 10 displayed on the monitor TV 6 in the X and Y directions.

The laser cut switch 7o is used to automatically perform laser cutting according to a preset cutting pattern, and a switch is installed for each mode so that cutting can be performed in one action.

Further, a host CPU 44 is provided to manage all control of this inspection/repair apparatus, and a test sequence and various test conditions are set in this host CPU 44.

Next, the operation will be explained with reference to the flowchart in FIG.

First, perform initial settings according to steps 1 to 4.
In step 1, various initial settings are performed by operating the operation panel 5 of the laser repair device 3. Here, (2) in step 1 of FIG.

The setting (3) is shown in FIG. 6(A) as described above.

This is executed according to the procedure (B).

In this embodiment, the laser optical axis and camera optical axis are aligned above the substrate 10, so by making the above settings, the actual irradiation position of the laser beam from the laser oscillator 51 can be adjusted to Since the cursor intersections will surely match on the monitor TV 6, if the defective pattern is made to coincide with this cursor intersection point from now on, the laser beam can be reliably irradiated to the defective pattern at all times.

Next, in steps 2 to 4, initial settings of the laser optical system, initial settings of the host CPU 44, setting of the substrate cassette in the loader device 1, etc. are executed, respectively.

Next, the LCD board 10 is attached to the probe mount W from the loader device 1.
Since test and repair are selected in step 5) and step 6, a probing test will be performed with the probe device 2 (step 7).

Before explaining the operation of this probe device 2, the structure of the LCD board 10 will be explained with reference to FIG. 8.

A large number of pixels 80 including transparent electrodes, pudge bait films, alignment films, etc. are formed on an active matrix type liquid crystal substrate.

Each of these pixels 80 has an MQS type TFT.
81 are arranged and 1. : The gates of the QOS type TFT 81 are connected to gate lines (also called signal lines) 82a, 82b, 82cm, and the sources are connected to source lines (also called scanning lines) 83a, 83b, respectively.
, 83c... In addition, HO8 type TF
The drains of T81 are each connected to a transparent electrode within the vixel 80.

Further, the gate lines 83a, 83b, 83c...
・ is a gate lead electrode 84 formed at the end of the substrate 10
a, 84b, 84c... and their opposing electric currents 184a-,
84b-, 84cm---, respectively.

Also, the source line 83a.

Similarly, source lead electrodes 85a, 83b and 83c
5b, 8!5cm and its opposite tfi85a85b-
Each is connected to 85cm.

In the probe device 2, the gate line,
Tests are performed on the insulation resistance value at the intersection of source lines, the presence or absence of short circuits between adjacent lines, the presence or absence of each line@line, etc.

For this reason, each of the above-mentioned tests is carried out by bringing the probe board shown in FIG. 3 into contact with the electrodes and switching the lines to be energized.

For example, when inspecting the insulation resistance value at the intersection of the source line and the gate line, the source lead electrode 85a is
This can be carried out by applying a voltage of 12V and measuring the current flowing to the gate line 82a through the intersection of the source line 83a and the gate line 82a. Thereafter, the insulation resistance value at each intersection can be measured in the same manner.

In addition, when inspecting for short circuits between lines and the @ line of each line, a counter electrode can be used for inspection.

In carrying out the above inspection, the inspection method previously proposed by the present applicant (Japanese Patent Application No. 62-286872, Japanese Patent Application No. 62-303951) can be suitably employed.

Here, when performing various inspections as mentioned above,
As a precondition for this, it is necessary that the contact portion of the probe board properly contacts each of the above-mentioned electrodes. For this purpose,
It is necessary that the alignment of the LCD board 10 is achieved.

In this embodiment, the above alignment is performed with the LCD 10 set at the probing position A, and the microscope 8
A part of the surface of the LCD 10 is enlarged and photographed by the alignment camera 41 via the camera 41, and this is displayed on the monitor TV 6 and manually adjusted using a joystick or the like, or a photographic pattern and a pattern at a pre-stored regular position are taken. Alignment is performed by comparing these and automatically adjusting them so that they match.

In this way, by making the probing position and the alignment position the same, compared to a conventional IC probe device that executes alignment before reaching the probing position, the machine on the conveyance route after alignment is It is possible to prevent deterioration of probe position accuracy due to superimposition of target errors.

If a disconnection defect, short circuit defect, etc. occurs in the above inspection, the address and contents of this defect are stored in the memory 46 by the tester 30 via the controller 42.

When all inspections have been completed, it is determined whether or not this LCD board 10 is defective (step 8). If a defect occurs, the next operation is started in the repair device 3.

In other words, if the LCD board 1 has this defect, especially a short circuit,
0 is loaded into the laser initial position of the repair device 3 by driving the stage 40 (step 9).

Next, the stage 40 is moved according to the address information in the memory 46, and the position of the first defective pattern is set to match the laser spot position (step 10). At this point, it is determined whether the mode is automatic or manual. (Step 11), in the case of manual operation, the stage 40 is driven in the Z direction by the Z-axis movement switch 77 to focus the repair monitor camera 60, and this is repeated until the focus is achieved (Step 12.13).

If the focus is achieved in manual mode or if auto mode is selected, then press joystick 7.
Fine alignment between the laser spot position and the defective pattern position is performed by the following steps (step 14).

In this fine alignment, the repair monitor camera 60 enlarges and photographs the defective pattern, displays it on the monitor TV 6, and aligns the defective pattern with the intersection of the cursor 5a displayed superimposed on the monitor TV 6. Then, the joystick 79 is operated.

If there is a position (step 16), then the cut mode is selected and the laser cut switch 70 is pressed (step 17).

Next, it is determined whether the drive is step drive or continuous drive, and if it is continuous drive, it is determined whether there are any more defective patterns after cutting (step 20), and if there are any defective patterns, the process returns to step 10. Repeat the same action.

In the case of step drive, it is determined whether the cut is OK or not (step 18), and if it is OK, the start switch 76
By pressing (step 19), the process moves to step 20, and if a defective pattern exists, the process returns to step 10 and the same operation is repeated.

In addition, in the above-mentioned pattern cutting with laser light, in this embodiment, the laser can be reliably irradiated to the alignment position of the defective pattern using the alignment camera 60, and therefore there is no positional deviation of laser irradiation. Therefore, reliable laser cutting can be performed.

This is because the optical axis of the alignment camera 60 and the optical axis of the laser beam are coaxial as shown in FIG. Therefore, it is possible to reduce the size and cost of the device.

Furthermore, if insulation failure occurs in wiring at line intersections, one side of the line will be laser cut, and rewiring processing will be required later in another process using a method such as wire bonding. In order to reliably execute this post-process, if the information is transmitted using some kind of medium (floppy disk, printer paper), etc., management is not only complicated and inconvenient, but also errors in the post-process are likely to occur.

Therefore, in this embodiment, when one line is laser-cut due to poor insulation at the line intersection, a laser beam is irradiated to, for example, the end (area other than the pattern) of the cut line. I'm trying to use it as a marker.

Since this marker can be identified in a subsequent process to recognize a defective address, it is possible to reliably perform the rewiring process without requiring any media. Note that when using a cutting laser as a marker for post-processing, the marking position can be modified in various ways. Bye.

When laser cutting has been completed for all defective patterns, the stage 40 is driven to transport the LCD board 10 back to the blower device 2, and retest only the defective patterns (step 21).

If the inspection and repair are completed in this way and the retest is OK (step 22), the board 10 is returned to the carrier cassette of the loader device 1 and transported (step 23).
The same inspection and repair are repeated for all the substrates 10 set in the loader device, and the sequence ends when all lots are completed (step 24).

Note that the present invention is not limited to the above embodiments,
Various modifications are possible within the scope of the invention.

The present invention is not necessarily applied to a laser repair device for LCDs, but can be applied to various fields in which repairs are performed by irradiation with laser light, such as printed circuit boards.

[Effects of the Invention] As explained above, according to the present invention, by making the optical axis of the laser light source and the alignment or monitoring camera coaxial with respect to the board to be repaired, the board can be repaired based on the camera notification. By performing this alignment, it is possible to accurately irradiate the laser beam at the determined position, prevent the irradiation position from shifting, and simplify the configuration of the optical system, which reduces the size of the device and reduces costs. It is possible to aim for

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of an LCD board inspection/repair device to which the present invention is applied. FIG. 2 is a schematic explanatory diagram for explaining the electrode area of the LCD. FIGS. 3 (A) and (B) 4 is a block diagram of the device shown in FIG. 1, FIG. 5 is a schematic plan view showing the operation panel for the repair device, and FIG. 6A and 6B are schematic explanatory diagrams for explaining the operation of aligning the laser spot and the cursor intersection point at the initial time, and FIG. 7 is a flowchart for explaining the operation of the embodiment device. , FIG. 8 is a schematic explanatory diagram for explaining the pattern configuration of the LCD board. 60...camera,

Claims (1)

[Scope of Claims] A laser source for irradiating a laser beam onto a defective pattern on a board to be repaired, and a camera for aligning or displaying the board on a monitor. A laser repair device for repairing a defective pattern by irradiating a laser beam after aligning the pattern to a laser spot position, wherein the laser source and the optical axis of the camera with respect to the substrate are coaxial.