JPH0682802A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To inspect an electric connection state right after a semiconductor chip is mounted by providing patterns for connection resistance measurement which are mutually connected on the top surface of a transparent glass substrate and the reverse surface of the semiconductor chip. CONSTITUTION:Two electrodes 2a and a pattern 2 for connection resistance measurement which connects them are provided at each of the four corner parts on the reverse surface of the semiconductor chip 4 separately from an electrode 9 for connection, and an electrode 1a which is connected to the electrode 2a of the semiconductor chip 4, a pattern 1 for connection resistance measurement which is connected thereto, and an electrode 1b at its end part are provided on the top surface of the lower transparent glass substrate 3 at the positions corresponding to the electrodes and patterns. The probe of a resistance measuring instrument is applied to two adjacent electrodes (terminal) 1b of the lower transparent glass substrate 3 positioned nearby each corner part of the mounted semiconductor chip 4 and the connection resistance is measured. When the resistance value is larger than a specific value, the semiconductor chip 4 is defective, so it is removed and a new chip is mounted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a COG (Chip On Glass (Chip On Glass) in which a liquid crystal driving semiconductor chip is directly mounted on an electrode of a transparent glass substrate of a liquid crystal display element.
lass)) type liquid crystal display device, and more particularly to a technique capable of confirming an electrical connection state of the semiconductor chip immediately after mounting.

[0002]

2. Description of the Related Art In a COG type liquid crystal display device, an upper transparent glass substrate and a lower transparent glass substrate are separated by a predetermined distance so that the surfaces on which electrodes made of a transparent conductive film and an alignment film are laminated face each other. A liquid crystal display element is obtained by stacking and sealing the liquid crystal between both substrates by bonding both substrates with a sealing material provided around the edge between the both substrates, and further bonding a polarizing plate on the outside of both substrates. A plurality of liquid crystal driving semiconductor chips are directly mounted on the lower transparent glass substrate having the drive wiring around the upper transparent glass substrate, which is not overlapped with the upper transparent glass substrate. The semiconductor chip and the lower transparent glass substrate are electrically connected to each other via a protruding electrode (bump) formed on one of the lower surface of the semiconductor chip and the surface of the lower transparent glass substrate which face each other. Such a connection method is called a face-down method.

Such a technique is disclosed in, for example, Japanese Patent Application Laid-Open No. 52-3.
It is described in JP-A-5548, JP-A-3-18826 and the like.

[0004]

In the prior art, no consideration was given to the confirmation of the electrical connection state of the semiconductor chip after mounting the semiconductor chip on the electrodes of the transparent glass substrate. That is, it is not possible to inspect the electrical connection state immediately after the semiconductor chip is mounted, and it is possible to determine whether the semiconductor chip is normally connected without a lighting inspection after the product of the liquid crystal display device is completed. Therefore, there is a problem in that it is impossible to find a defective connection of the semiconductor chip.

An object of the present invention is to provide a liquid crystal display device capable of inspecting an electrical connection state immediately after mounting a semiconductor chip and having high connection reliability.

[0006]

In order to achieve the above object, the present invention provides an electrical connection between an electrode of a semiconductor chip and an electrode of a transparent glass substrate mounted on the upper surface of a transparent glass substrate and the lower surface of a semiconductor chip. Provided is a liquid crystal display device provided with connection resistance measurement patterns, which are connected to each other when a semiconductor chip is mounted, for inspecting a connection state.

[0007]

In the present invention, the connection resistance of the connection resistance measuring pattern is measured immediately after the semiconductor chip is mounted, and the electrical connection state between the electrode of the semiconductor chip and the electrode of the transparent glass substrate is inspected according to the magnitude of the connection resistance. , You can judge.
It is possible to provide a liquid crystal display device with high connection reliability in which all semiconductor chips are normally connected by removing a semiconductor chip with a connection failure having a resistance value larger than a predetermined value and then re-mounting the semiconductor chips. it can.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is an exploded perspective view of an embodiment of a COG type liquid crystal display device.

Reference numeral 13 denotes a metallic upper shield case, 14 denotes a fixing claw integrally formed with the upper shield case 13, and 1
Reference numeral 5 is a spacer for fixing each component made of rubber or the like, 5 is a liquid crystal display element, 6 is an upper transparent glass substrate which constitutes the liquid crystal display element 5, and 3 is a lower transparent glass substrate which constitutes the liquid crystal display element 5. An upper transparent glass substrate 6 is superposed on the lower transparent glass substrate 3, and a liquid crystal (not shown here) is sealed between the two substrates by a sealing material provided around the edges of both substrates. The lower transparent glass substrate 3 has a larger outer circumference than the upper transparent glass substrate 6 as shown in the drawing, and the outer peripheral portions of the four sides of the upper transparent glass substrate 6 are drive wiring formation regions of the liquid crystal display element 5. Reference numeral 4 is a liquid crystal driving semiconductor chip, 7 is a driving input wiring pattern for the semiconductor chip 4 formed on the outer peripheral portion of the lower transparent glass substrate 3, and 8 is a driving input wiring pattern formed on the outer peripheral portion of the lower transparent glass substrate 3. Output wiring pattern, 16
Each of a, 16b, 16c, and 16d has a driving circuit, and is connected to the periphery of the four sides of the lower transparent glass substrate 3 F
PC (Flexible Printed Circuit), 17
Is a metal lower shield case, 18 is provided in the lower shield case 17, and fixing claws 14 of the upper shield case 13 are provided.
Is a fixing hole into which is inserted and caulked.

FIG. 1A is a plan view of a main part of a liquid crystal display element of a liquid crystal display device according to an embodiment of the present invention, showing a connection resistance measuring pattern provided on a lower transparent glass substrate surface. is there.

On the other hand, FIG. 1 (b) is a plan view of the lower surface of the liquid crystal driving semiconductor chip mounted on the lower transparent glass substrate shown in FIG. 1 (a), showing the connection resistance provided on the lower surface of the semiconductor chip. It is a figure which shows the pattern for a measurement.

FIG. 2 (a) is a plan view of relevant parts showing a state in which the semiconductor chip shown in FIG. 1 (b) is mounted on the lower transparent glass substrate shown in FIG. 1 (a). Figure 2
2B is a sectional view taken along the line AA ′ in FIG.

In FIG. 1A, 5 is a liquid crystal display element,
6 is an upper transparent glass substrate, 3 is a lower transparent glass substrate, 7
Is a drive input wiring pattern of a semiconductor chip (not shown here), 7a is an electrode of the drive input wiring pattern 7 (input terminal for external signal voltage, power supply voltage), and 7b is an electrode of the semiconductor chip (FIG. 1). (B) protruding electrode (bump) 9)
An electrode (output terminal) of the drive input wiring pattern 7 connected to the drive electrode, 8 a drive output wiring pattern, and 8a a drive connected to the electrode of the semiconductor chip (protruding electrode (bump) 9 in FIG. 1B) Electrode (input terminal) of the output wiring pattern 8 for
Reference numeral 1 is a connection resistance measurement pattern formed on the upper surface of the transparent glass substrate 3, and 1a is an electrode of the connection resistance measurement pattern 1.

In FIG. 1B, 4 is a liquid crystal driving semiconductor chip, and 9 is formed on the lower surface of the semiconductor chip 4 corresponding to the electrodes 7b and 8a of the lower transparent glass substrate 3 of FIG. 1A. Electrodes (protrusion electrodes (bumps)), 2 are connection resistance measurement patterns formed on the lower surface of the semiconductor chip 4, and 2a are electrodes of the connection resistance measurement pattern 2 (protrusion electrodes similar to the electrodes 9).

In FIG. 2B, 10 is provided between the semiconductor chip 4 and the lower transparent glass substrate 3, and
An anisotropic conductive adhesive for connecting the electrodes 9 and 2a of the semiconductor chip 4 and the electrodes 7b, 8a and 1a of the lower transparent glass substrate 3 shown in FIGS. 11 is a liquid crystal sealed between the upper transparent glass substrate 6 and the lower transparent glass substrate 3, 12 is provided around the edge of the upper transparent glass substrate 6 and the lower transparent glass substrate 3, and both substrates are bonded together, It is a sealing material that seals the liquid crystal 11 between both substrates.

The electrodes 9 formed on the lower surface of the liquid crystal driving semiconductor chip 4 include the electrodes 7b and 8a formed on the upper surface of the lower transparent glass substrate 3 of the liquid crystal display element 5 and the anisotropic conductive adhesive 10. The signal voltage and the power supply voltage, which are electrically connected via the drive input wiring pattern 7, pass through the semiconductor chip 4 and the drive output pattern 8 and the liquid crystal display element 5.
Is output to. Conventionally, it has not been possible to judge whether the electrode 9 of the semiconductor chip 4 and the electrodes 7b and 8a of the lower transparent glass substrate 3 are electrically connected well.
In this embodiment, two electrodes 2a are provided on each of the four corners of the lower surface of the semiconductor chip 4 in addition to the connecting electrodes 9.
Also, a connection resistance measuring pattern 2 for conducting these is provided, and an electrode 1a connected to the electrode 2a of the semiconductor chip 4 is connected to the electrode 2a of the lower transparent glass substrate 3 at a position corresponding thereto. The connection resistance measuring pattern 1 and the electrode 1b were provided on the end portion thereof.

After the semiconductor chip 4 is mounted on the lower transparent glass substrate 3, the electrical connection between the electrodes 7b and 8a of the lower transparent glass substrate 3 and the electrode 9 of the semiconductor chip 4 is inspected. When the semiconductor chip 4 is mounted, the connection resistance measuring pattern 2 of the semiconductor chip 4 and the connection resistance measuring pattern 1 of the lower transparent glass substrate 3 correspond to the electrode 2a of the semiconductor chip 4 and the electrode 1a of the lower transparent glass substrate 3. Conducts through. Therefore, the lower transparent glass substrate 3 located near each corner of the mounted semiconductor chip 4
The probes of two resistance measuring devices (not shown) are applied to the two adjacent electrodes (terminals) 1b of 1 to measure the connection resistance.
If the resistance value is larger than a predetermined value, this semiconductor chip 4
Since the connection of is bad, remove this semiconductor chip 4,
The semiconductor chip 4 is remounted. After remounting, reinspection is performed in the same manner as above, and the electrical connection state is confirmed. The electrical connection state of the dummy electrodes 1a and 2a located at the corners of the semiconductor chip 4 is almost the same as the electrical connection state of the regular connection electrodes 7b, 8a and 9 located inside thereof. From this, it is possible to confirm the electrical connection state of the latter electrodes. As a result, all the semiconductor chips 4 can be normally connected, and a liquid crystal display device with high connection reliability can be provided. Further, according to this embodiment, the semiconductor chip 4 having a resistance value larger than a predetermined value is removed, so that the connection resistance of the semiconductor chip 4 can be stabilized. Furthermore, the semiconductor chip 4 to be repaired can be determined not only immediately after mounting the semiconductor chip 4 but also by measuring the connection resistance in the same manner as described above.

Although the present invention has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and it is needless to say that various modifications can be made without departing from the scope of the invention. . For example, the present invention can be applied to both a simple matrix type liquid crystal display device and an active matrix type liquid crystal display device using a TFT (thin film transistor) or the like as a switching element.
Also, the connection resistance measurement patterns 1 and 2 and the electrode 1 thereof.
Needless to say, the shapes, positions, etc. of a, 1b, 2a are not limited to those shown in the above embodiment, and other shapes and positions may be used.

[0019]

As described above, according to the present invention,
After mounting the LCD driving semiconductor chip on the transparent glass substrate, the connection state between the semiconductor chip electrode and the transparent glass substrate electrode can be electrically measured, so the defective semiconductor chip can be detected and eliminated. can do. As a result, a liquid crystal display device with high connection reliability can be provided.

[Brief description of drawings]

1A is a plan view of a main part of a liquid crystal display element of a liquid crystal display device according to an embodiment of the present invention, and FIG. 1B is a semiconductor chip for driving a liquid crystal mounted on the liquid crystal display element of FIG. 2 is a plan view of the lower surface of FIG.

FIG. 2A is a view showing the semiconductor chip of FIG.
FIG. 7A is a plan view of relevant parts showing a state of being mounted on the lower transparent glass substrate of FIG. 7A, and FIG. 9B is a sectional view taken along the line AA ′ of FIG.

FIG. 3 is an exploded perspective view of an embodiment of a COG type liquid crystal display device.

[Explanation of symbols]

1, 2 ... Connection resistance measurement patterns 1a, 1b, 2a ...
Electrodes, 3 ... Lower transparent glass substrate, 4 ... Liquid crystal driving semiconductor chip, 5 ... Liquid crystal display element, 6 ... Upper transparent glass substrate,
7 ... Driving input wiring pattern, 7a, 7b, 8a ... Electrode, 8 ... Driving output wiring pattern, 9 ... Electrode (bump) 10 ... Anisotropic conductive adhesive, 11 ... Liquid crystal, 12 ... Sealing material 13 ... Top Shield case, 14 ... Fixing claw, 15 ... Fixing spacer, 16a, 16b, 16c, 16d ... FP
C, 17 ... Lower shield case, 18 ... Fixing hole.

Claims (1)

[Claims] 1. A COG in which a liquid crystal driving semiconductor chip is directly mounted on an electrode of a transparent glass substrate of a liquid crystal display element.
In the liquid crystal display device of the method, in order to inspect the electrical connection state between the electrode of the semiconductor chip and the electrode of the transparent glass substrate mounted on the upper surface of the transparent glass substrate and the lower surface of the semiconductor chip, the semiconductor A liquid crystal display device, wherein each of the liquid crystal display devices is provided with a connection resistance measuring pattern which is connected to each other when the chip is mounted.