JP2003337315A - Probe card for inspecting short circuit between surfaces of liquid crystal panel and method for roughly screening liquid crystal panel by inter-surface short circuit inspection - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently select a COG-LCD panel. <P>SOLUTION: A short circuit between upper and lower glasses is inspected by using a probe card for inspection which has: an electrode pattern for inspection for connecting all segment electrodes of simple constitution together at a time before an LCD driving IC is mounted on the panel; and an electrode pattern for inspection for connecting common electrodes provided at both ends of the segment electrodes together at a time in order to sort non-defective panels from defective panels, thus performing rough screening as to whether the LCD panel is a non-defective article or a defective article. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection probe for performing an inter-surface short inspection of upper and lower panel surfaces of an LCD (liquid crystal display device) and a panel before mounting an LCD driving IC using the inspection probe. Regarding the inspection method.

[0002]

2. Description of the Related Art Currently, LC is used as a display device for information equipment and the like.
D is often used, but to drive the LCD, L
An IC for driving the CD is required. As an IC mounting method for an LCD, there is a method of directly mounting an IC chip on a glass substrate when mounting an LCD driving IC on a panel. This panel is COG (CHIP ON GLAS
S) -referred to as LCD panel, shown in FIG. The panel is composed of upper and lower two glasses 31 and 32 which sandwich liquid crystal, and an IC for driving the LCD is directly mounted on the LCD driving IC mounting portion 2 on the substrate of the lower glass 32.
The lower glass 32 is a part for mounting an IC. The mounting portion 2 has a rectangular shape indicated by a broken line, and a segment electrode 21 is arranged along one side of the peripheral portion of the mounting portion 2, and common electrodes 22 and 22 'are arranged along two sides orthogonal to the side. ing. Reference numeral 23 is a power supply / signal input / output electrode, which inputs and outputs a power supply for the LCD driving IC and a display signal. When the LCD driving IC is mounted, the lead wires of the corresponding LCD driving IC are connected to the electrodes 21, 22, 22 'and 23.

FIG. 4 is a sectional view taken along the broken line in FIG. 3, in which the wiring 36 of the upper glass 31 is L on the lower glass 32.
It shows a state of reaching the mounting portion 2 of the CD driving IC. The wiring 36 of the upper glass 31 is a segment (SEGMEN) located in the longitudinal direction of the IC mounting portion 2 of the lower glass 32, which will be described later, through the sealant 35.
T) It is connected to the electrode 21. The wiring (not shown) of the lower glass 32 is divided into two common (COMM).
(ON) electrodes 22, 22 '. The display control of the LCD is performed by controlling the voltage applied between the upper glass wiring 36 and the lower glass wiring.

By the way, the LCD may be contaminated by the inclusion of dust in the manufacturing process or the handling by a person. In particular, conductive foreign matter may not be removed even by visual inspection, and it may cause a short circuit between the segment electrode and the common electrode, resulting in defective display in the area where the conductive foreign matter exists on the LCD display surface. Cause the panel to fail. Therefore LCD
Inspection of conductive foreign matter is indispensable in the manufacturing process.

Japanese Unexamined Patent Publication No. 2002-107688 (20
02.4.10), a method of using a full-contact type panel prober and a conventional method for testing all data lines and all gate lines (also referred to as scanning lines) of a liquid crystal display panel are used. There is a method of using a so-called solid display jig that makes a collective contact with a conductive rubber or a flexible pattern substrate. The method of using this full-contact type panel prober is to contact probe pins to all terminals of the liquid crystal display panel, and electrically connect the driver module and the liquid crystal display panel through these probe pins. The driver module is provided with a drive circuit equivalent to that used in an actual product, and a predetermined signal is supplied from the driver module to the liquid crystal display panel to inspect the lighting / non-lighting state of each pixel. is there. By the way, at present, the electrodes are becoming finer, and the electrode pitch of the panel is a narrow pitch of about 100 μm or less. However, it is very difficult to make an inspection probe having such a fine pitch, and therefore, the inspection is difficult. The production of the probe for use requires a great deal of cost. In addition, even if the probe is manufactured, IC is used at the time of inspection.
The segment electrode 21 and the common electrodes 22, 2 of the mounting portion 2
Corresponding to 1 pin 1 pin of 2 ', the inspection segment electrode 51 and the inspection common electrodes 52, 52' of the inspection probe.
It is necessary to perform the inspection by aligning the positions of the electrodes, but for positioning the electrodes with a fine pitch, it is necessary to use a high-precision positioning device, such as using image processing technology, and the inspection process requires a long time. is doing. In addition, there are various types of driving ICs, and a probe card must be prepared for each type according to this, which is complicated. On the other hand, in the method of using the solid display jig, the solid display jig is provided with a wiring pattern for collectively connecting all data wirings and a wiring pattern for collectively connecting all gate wirings. Then, the inspection device and the liquid crystal display panel are connected via this solid display jig to supply the same gate signal (also referred to as a scanning signal) to all the gate wirings and the same display signal to all the data wirings. To do. According to this method, the same gate signal is supplied to all gate wirings and the same display signal is supplied to all data wirings. Although the method of using the solid display jig has a lower inspection cost than the method of using the panel prober, it has a drawback that it cannot detect a subtle defect because it cannot display a complicated display pattern. .

In addition to the above method, there is also a method of optically reading the surface of the liquid crystal and detecting the presence or absence of foreign matter such as dust by pattern recognition (Japanese Patent Laid-Open No. 2001-914).
No. 75, Japanese Patent Application Laid-Open No. 11-304714), this method has a problem in that a highly accurate inspection device is required and the inspection device becomes large-scale. (JP 2001-91475 A, JP 11-30471 A)
No. 4, etc.) In any of the above methods, the LCD short circuit inspection is performed after the IC is mounted on the LCD panel. However, if a defective product is found at the inspection stage, not only the panel but also the good product IC should be discarded. It must be uneconomical.

[0007]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above problems and to efficiently select an LCD panel.

[0008]

According to a first aspect of the invention, an LCD corresponding to an electrode of a rectangular LCD driving IC mounting portion is formed.
A probe card for panel inspection, in which a single segment electrode for inspection is arranged corresponding to a segment electrode of a mounting portion, and a single segment for inspection is provided at both ends of the segment electrode for inspection, perpendicularly to the segment electrode. A rectangular COG in which the common electrode is arranged corresponding to the common electrode of the mounting portion.
A probe card for in-plane short-circuit inspection of LCD panels. According to a second aspect of the present invention, before mounting the liquid crystal driving IC on the panel, the probe card according to the first aspect is used to inspect an inter-plane short circuit of the LCD panel to perform LC.
LC after rough broiling of D panel
This is a method of inspecting an LCD panel by inspecting a full contact for each pin of the D panel.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows the configuration of a COG-LCD panel inspection probe card 1 of the present invention. FIG. 1A is a front view of the card 1, and FIG. 1B is a side view of the card 1. In the present embodiment, a strip-shaped strip-shaped inspection segment electrode 11 is provided in the longitudinal direction of the card as an electrode pattern on the rectangular card 1, and both ends of the inspection segment electrode are connected to both ends of the inspection segment electrode. A strip of common inspection electrodes 12, 12 'is provided in the vertical direction. FIG. 1B shows the segment electrode 11 for inspection,
The manner in which the inspection common electrodes 12, 12 'are connected to the back surface of the card by the wiring 15 is shown. The wiring 15 is connected to a processing device (not shown), and a short circuit is inspected.

Electrode of inspection probe and LCD driving IC
2 shows the correspondence with the electrode pattern of the mounting portion. In the figure, the same parts as those in the related art are given the same numbers.
The segment electrode 21 is an electrode connected to the wiring of the upper glass through the LCD sealant.
Reference numeral 2'denotes electrodes on the left and right sides of the IC mounting portion and connected to the wiring of the lower glass as described above. Reference numeral 23 is an input / output unit for power and signals. Inspection segment electrode 11 shown in FIG.
Is a strip-shaped conductor that short-circuits all the segment electrodes 21 of the mounting portion across the segment electrodes 21 of the IC mounting portion 2. The length is a length that exceeds and covers the segment electrode width of the mounting portion so that it can contact all the individual electrodes that form the segment electrode 21 of the mounting portion. Similarly, the inspection common electrodes 12 and 12 'are strip-shaped conductors that short-circuit all the common electrodes 22 and 22' of the mounting portion across the common electrodes 22 and 22 'of the IC mounting portion. The length exceeds the width of each common electrode so as to be able to contact all of the individual electrodes that form the common electrodes 22 and 22 'of the mounting portion, and covers this.

Next, a face-to-face short-circuit inspection of the upper and lower glass substrates for the LCD panel using the probe card described above will be described. In the present invention, the LCD panel is roughly defective or defective, so that the LCD panel is inspected before the driving IC is mounted on the panel. The inspection segment electrode 11 of the probe card is located at the position a of the segment electrode 21 of the mounting portion, and the inspection common electrodes 12 and 12 '.
Aligns with the position b of the common electrodes 22, 22 'of the mounting portion 2. At this time, the segment electrode 1 for card inspection
1 and the common electrodes 12 and 12 'for inspection are both strip-shaped electrodes and contact the segment electrodes 21 and the common electrodes 22 and 22' of the mounting portion 2 in a transverse manner. There is no need to make precise alignment. The segment electrode 21 and the common electrodes 22 and 22 'of the mounting portion are used for the inspection segment electrode and the inspection common electrode 12 of the card.
It suffices that the 12 'are brought into contact with each other and a slight misalignment is allowed.

Next, in this state, when an inspection voltage is applied between the segment inspection electrode and the common inspection electrode of the card, the inspection voltage is applied to each segment electrode 21 of the IC mounting portion connected to the inspection probe card. Common electrode 2
2, 22 ', and the inspection voltage is applied to the wiring of the glass substrate sandwiching the upper and lower liquid crystals. Here, if no conductive foreign matter is mixed in, the inspection electrodes of the inspection probe card are in an open state, and this inspection voltage causes LC
D is turned on or off (all lighting) in all pixels.

However, when the conductive foreign matter is mixed, the inspection electrodes of the inspection probe card are short-circuited, and the voltage corresponding to this short-circuit is detected.
Also, in that state, the panel does not light up or becomes dark even if lighted up. That is, the panel is determined to be defective. According to the present embodiment, the inspection electrode pattern of the inspection probe card is a simple strip-shaped electrode pattern, which can be easily produced, and is produced by the electrode pattern arranged at high density for each pin as in the prior art. There is no need to do it.

Further, if the position of the inspection probe is slightly displaced, the inspection common electrode of the inspection probe may contact the segment electrode of the mounting portion. It is desirable to lay out the electrodes of the panel mounting portion so that the common electrodes are separated by an appropriate distance.

The defective panel is removed by this surface-to-surface short inspection, and LC is then applied to the selected good liquid crystal panel.
A D drive IC is attached, and the probe pin of the panel prober is brought into contact with each pin of the segment electrode and the common electrode. Then, the LCD driving IC and the LCD panel are electrically connected, a display signal is supplied from the LCD driving IC to the LCD panel, and the lighting / non-lighting state of each pixel is inspected.

[0016]

According to the present invention, the following effects can be obtained. 1. Since a simple inter-plane short circuit inspection can be performed before the IC is mounted and the rough bleeding of the defective panel can be easily performed, it is not necessary to discard the good product IC which was discarded by the conventional method. In addition, after eliminating defective panels by rough bluing, LCD driving ICs are mounted on non-defective panels and highly accurate inspection is performed for each pin, so the number of panels to be inspected is smaller than in the past. Therefore, the inspection efficiency is improved as a whole.

2. Since voltage is applied to all pins when performing the face-to-face short-circuit inspection, L
It is possible to inspect all lighting of the CD device, and it is possible to confirm that there is no wire dropout and that there is no break in the electrode pattern.

[Brief description of drawings]

FIG. 1 shows a probe card structure for inspection of the present invention.

FIG. 2 shows a relationship between an inspection probe and an IC mounting portion according to the present invention.

FIG. 3 is a schematic view of a conventional COG-LCD panel.

FIG. 4 shows a sectional structure of the LCD of FIG.

FIG. 5 Conventional probe card for inspection

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Probe card for inspection, 11 ... Segment electrode for inspection of probe card for inspection, 12, 12 '... Common electrode for inspection of probe card for inspection, 2 ... IC for driving LCD
, 21 ... Segment electrodes in the LCD driving IC mounting section, 22, 22 '... Common electrodes in the LCD driving IC mounting section, 23 ... Power / signal input / output electrodes in the LCD driving IC mounting section 3 ... LCD panel, 31 ... Upper glass, 32 ... Lower glass, 33 ... IC mounting part, 34 ... Liquid crystal, 35 ... Sealant, 36 ... Wiring, 5 ... Conventional probe card, 51 ... On conventional probe card Segment electrodes, 52, 52 '... Common electrodes on conventional probe cards.

Claims (2)

[Claims] 1. A probe card for LCD panel inspection corresponding to an electrode of a rectangular LCD driving IC mounting portion, wherein a single segment electrode for inspection is arranged corresponding to the segment electrode of the mounting portion. Card for in-plane short-circuit inspection of a rectangular COG-LCD panel in which a strip of inspection common electrode is arranged at both ends of each of the segment electrodes perpendicularly to the segment electrode corresponding to the common electrode of the mounting portion. . 2. Before mounting the liquid crystal driving IC on the COG-LCD panel, the probe card according to claim 1 is used to inspect the LCD panel for a surface short circuit to roughen the LCD panel. After that, a method of inspecting the LCD panel by inspecting the LCD panel selected by rough brui by full contact for each pin.