JPH0317614A - Production of active matrix display device - Google Patents

Abstract

PURPOSE:To detect the defects of picture elements in the production stage of an active matrix substrate by sealing a display medium between the active matrix substrate and a counter substrate. CONSTITUTION:Twisted nematic liquid crystal molecules 18 are sealed as the display medium between a pair of glass substrates 1 and 20. The liquid crystal molecules 18 are oriented and converted by responding to the impressed voltages between picture element electrodes 5 and a counter electrode 22, by which optical modulation is executed. The optical modulation is visually admitted as display patterns. The driving voltage is impressed to all the picture element electrodes 5 via main TFTs 6 from all the wirings of gate bus wirings 3 and source bus wirings 4 of the liquid crystal display device having the above- mentioned constitution. The defects of the picture elements are easily visually recognized in the state in which all the picture element electrodes are driven in this state. The easy correction of the defect is possible by using a connecting part 25 if the defect of the picture element is generated by the defect of the main TFT 6.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a display device that performs display by applying a drive signal to a display picture element electrode via a switching element. The present invention relates to a method of manufacturing an active matrix drive type display device that performs high-density display by arranging electrodes in a matrix.

(Prior Art) Conventionally, in liquid crystal display devices, EL display devices, plasma display devices, etc., display patterns are formed on the screen by selectively driving pixel electrodes arranged in a matrix. Ru. A voltage is applied between a selected picture element electrode and a counter electrode facing the selected picture element electrode, and optical modulation of the display medium interposed therebetween is performed. This optical modulation is visually recognized as a display pattern. As a driving method for picture element electrodes, an active matrix driving method is known in which individual independent picture element electrodes are arranged and a switching element is connected to each of the picture element electrodes and driven. Switching elements that selectively drive picture element electrodes include TPT (thin film transistor) elements, MIM (metal-insulating layer-metal) elements, and MIM (metal-insulating layer-metal) elements.
OS} transistor elements, diodes, varistors, etc. are generally known.

The active matrix drive method is capable of high-contrast display and has been put to practical use in liquid crystal televisions, word processors, computer terminal display devices, and the like.

(Problem B to be Solved by the Invention) When performing high-density display on a large screen using such a display device, it is necessary to arrange a very large number of picture element electrodes and switching elements. However, the switching element may be formed as a malfunctioning element at the time of fabrication on the substrate.

A picture element electrode connected to such a defective element will cause a picture element defect that does not contribute to display.

For example, a configuration for correcting pixel defects is disclosed in Japanese Patent Application Laid-Open No. 61-1
It is disclosed in Japanese Patent No. 53619. In this configuration, a plurality of switching elements are provided for each picture element electrode. One of the plurality of switching elements is connected to the picture element electrode, and the others are not connected to the picture element electrode. If a switching element connected to a picture element electrode is defective, the switching element is separated from the picture element electrode using a laser trimmer, an ultrasonic cutter, or the like, and another switching element is connected to the picture element electrode. The switching element and the picture element electrode are connected by attaching a minute conductor using a dispenser or the like, or by coating a predetermined portion of the substrate with AuS At or the like.

Furthermore, JP-A-61-56382 and JP-A-59-
Japanese Patent No. 101693 discloses a configuration in which gold a layers are electrically connected to each other by irradiating laser light to melt the metal.

The above defect correction is performed on the active matrix substrate before the display device is assembled.

However, it is extremely difficult to detect pixel defects at the stage of manufacturing an active matrix substrate.

Especially in large display devices with 100,000 to 500,000 picture elements or more, extremely high-precision production equipment is required to detect the electrical characteristics of all picture element electrodes and discover defective switching elements. must be used. Therefore, the inspection process becomes complicated and mass productivity is hindered. This results in increased costs. For this reason, in large-sized display devices with a large number of picture elements, the position of pixel defect occurrence is not actually specified in the state of the substrate. Therefore,
It was not possible to correct pixel defects using the laser beam described above, and it was not possible to improve the manufacturing yield.

The present invention has been made to solve these problems. That is, an object of the present invention is to provide a method of manufacturing an active matrix display device with high yield.

(Means for Solving the Problems) A method for manufacturing an active matrix display device of the present invention includes:
A method for manufacturing an active matrix display device including a pair of substrates, at least one of which is translucent, and a display medium inserted between the substrates and whose optical characteristics are modulated in response to an applied voltage. A picture element electrode arranged in a matrix shape on the inner surface of one of the substrates of the tsM, a main switching element and a preliminary switching element electrically connected to the picture element electrode, and the main switching element. A scanning line connected to the element and the auxiliary switching element, a signal line connected to the main switching element, an extended end of the signal input terminal of the auxiliary switching element, and a branch wiring branched from the signal line. a step of forming a connecting portion which is disposed close to each other in a non-conducting state with at least an insulating film interposed therebetween; a step of forming a counter electrode on the other substrate of the pair of substrates; and a step of forming the display medium between the pair of substrates. applying a driving voltage to the display medium via the picture element electrode and the counter electrode,
a step of detecting a pixel defect; and a step of detecting a pixel defect; a step of irradiating energy to electrically connect the preliminary switching element and the signal line via the connection part; a wiring part between the main switching element and the signal line; The method includes a step of irradiating energy to one of the wiring sections between the main switching element and the picture element electrode to cut the wiring section, thereby achieving the above object. be done.

Further, the connecting portion may be replaced with a configuration in which the extending end of the signal input screw of the preliminary switching element and the signal line are opposed to each other.

(Function) In the method for manufacturing an active matrix display device of the present invention, picture element electrodes, main switching elements, auxiliary switching elements, scanning lines, signal lines, and connection parts are formed on the inner surface of an active matrix substrate. At the connecting portion, the extending end of the signal input terminal of the preliminary switching element and the branch wiring from the signal line or the signal line are closely opposed to each other. A counter electrode is formed on the counter substrate. After the display medium is sealed between the active matrix substrate and the counter substrate, a driving voltage is applied to all picture element electrodes. By driving all the pixel electrodes, the display medium correspondingly produces optical modulation depending on the driving voltage. However, if the main switching element is defective, this optical modulation will be incomplete and will be visually recognized as a pixel defect. This picture element defect can be easily identified using a magnifying lens or the like even on a substrate in which hundreds of thousands or more of minute picture element electrodes are arranged.

Once the pixel defect site is identified, energy such as a laser beam is irradiated from the outside to the connecting portion through the transparent substrate. At the connection part, the extension end of the signal input terminal of the preliminary switching element and the branch wiring or signal line branched from the signal line are electrically connected to each other by laser beam irradiation. In this way, the spare TFT 7 and the signal line are electrically connected via the connecting portion. Furthermore, the wiring between the main switching element and the signal line or the wiring between the main switching element and the picture element electrode is irradiated with energy and is cut, and the defective main switching element is connected to the signal line or the picture element electrode. separated from the electrode. Therefore, the picture element electrode is driven by the preliminary switching element.

(Example) The present invention will be described below with reference to an example. FIG. IA shows the structure of a display device manufactured by the manufacturing method of the present invention.
An example of an active matrix substrate is shown. B in Figure IA
The structure of each cross section along the -B line and the C-c line is shown in FIG. IB and FIG. IC.

In the manufacturing method of this embodiment, first, T
A base coat film 2 is formed from A205, A1203, SI3N4, etc. to a thickness of 3000 λ to 9000 λ. On the base coat film 2, gate bus lines 3 for supplying scanning signals and source bus lines 4 for supplying data signals are arranged in a grid pattern. Gate bus delivery! ! ! 3 is generally formed of a single layer or a multilayer metal such as Ta, AI, TiS Ni, MO, etc., but Ta is used in this embodiment. The bus wiring 4 is also made of the same metal, but
In this embodiment, Ti is used. At the intersection of the gate bus line 3 and the source bus line 4, a base insulating film 11 formed over the entire surface is interposed as will be described later.

In a rectangular area surrounded by the gate bus wiring 3 and the source bus wiring 4, a pixel electrode 5 made of a transparent conductive film (ITO) is provided.
are provided to form a matrix-like pixel pattern. A main TFT 6 is arranged as a main switching element near the corner of the picture element electrode 5, and the main TFT 6 and the picture element electrode 5 are electrically connected by a drain electrode l6. In the region where the picture element electrode 5 and the drain electrode 16 are connected, the width of the drain electrode l6 is small, and the picture element electrode 5 is provided with a notch. Such shapes of the drain electrode l6 and the picture element electrode 5 make it easy to later cut the drain electrode l6 using a laser beam or the like. A spare TF is provided near the other corner of the picture element electrode 5 as a spare switching element.
The preliminary T FT7 and the picture element electrode 5 are electrically connected by the drain electrode l6a.

The main TFT 6 and the preliminary @TFT 7 are arranged in parallel on the gate bus wiring 3, and the source electrode l5 of the main TFT 6 and the source bus wiring 4 are connected by a branch wiring 8. source electrode l
5 is formed in a shape with a partially reduced width so that it can be easily cut later with a laser beam or the like. The source electrode 15a of the TFT 7 is guided to the connection portion 25 by the source electrode extension end 8a. At the connecting portion 25, the source electrode extension end 8a
is placed opposite to the branch wiring 8 in a non-conducting state. Therefore,
Of the main TFT 6 and the spare TPT 7 , only the main TFT 6 is electrically connected to the source bus wiring 4 , and the preliminary TFT 7 is not connected to the source bus wiring 4 . Details of the cross-sectional configuration of the connecting portion 25 will be described later.

The cross-sectional structure of the vicinity of the main TFT 6 will be explained according to FIG. IB. Note that the cross-sectional configuration of the preliminary TFT 7 is also the same as that of the main TFT 6. A gate insulating film 10 made of Ta205 obtained by anodic oxidation of the surface of the gate electrode 9 is formed on a Ta gate electrode 9 formed as a part of the gate bus wiring 3. From above, a base insulating film 1l of SiNx (for example, Si3N4), which also functions as a gate insulating film, is deposited over the entire surface of the substrate. The thickness of the base insulation 11111 as a gate insulation film is 1500A to 600A.
Approximately A is suitable, but in this example, 2000A to 35
It is set to 00.

Amorphous silicon (a-S) is formed on the base insulating film 11.
The intrinsic semiconductor layer l2 of t) and the semiconductor layer protective film l3 made of SiN) which protects the upper surface of the intrinsic semiconductor layer 12 and functions as an etching stopper are sequentially laminated. Furthermore, an n-type semiconductor layer l4 made of a-Si is laminated from above to obtain ohmic contact with the source and drain electrodes to be formed later. A source electrode l5 and a drain electrode 16 are formed on the n-type semiconductor layer 14. The source electrode 15 and the drain electrode 16 are made of Ti, NfS At, or the like.

The cross-sectional configuration of the connecting portion 25 will be explained using FIG. 1C. A joint metal layer 24 is formed on the base coat y42. The shape of the joint metal layer 24 is rectangular in plan view, as shown in FIG. IA. Like the gate bus wiring 3, the joint metal layer 24 is made of TaSAl, Ti, Ni, Mo, etc.
The pattern can be formed simultaneously with the formation of the gate bus wiring 3. The above-mentioned base insulating film 1 is formed on the joint metal layer 24.
1 is deposited. A source electrode extension end 8a connected to the source electrode l5a of the preliminary TFT 7 and a branch wiring 8 connected to the source bus wiring 4 are placed on the joint metal layer 24 via the base insulating film l1. There is. The source electrode extension end 8a and the branch R8 are separated from each other and maintain a non-conducting state. Therefore, the spare TFT 7 is not electrically connected to the source bus wiring 4. The source electrode extension end 8a and the branch wiring 8 are completely covered with a protective film 17.

Joint metal layer 24, source electrode extension end 8a and branch wiring 8
The base insulating film 1l located between the two also functions as an interlayer insulating film between these metal layers and wiring. A thickness of 1000A to 7000A is suitable for the interlayer insulating film, but in this embodiment, the thickness of the main TPT. Since the base insulating film l1 which also functions as the gate insulating film of Nos. 6 and 7 is used, it is set to 2000λ to 3500λ as described above.

The protective film 17 is for electrically connecting the branch wiring 8 and the source electrode extension end 8a in a state where they are separated from the liquid crystal molecules 18 which are the display medium. Therefore, the appropriate thickness of the protective film 17 is about 1500A to 15000A. In this embodiment, since a protective film for the main TFTs 6 and 7 is used, the thickness thereof is set to around 5000 microns.

The picture element electrode 5 is patterned on the base insulating film l1. A protective film 17 made of SiNx is formed on the entire surface of the substrate, covering the upper surfaces of the main TFT 6 and the picture element electrode 5.
An alignment layer 19 for controlling the alignment of liquid crystal molecules 18 is deposited thereon. The alignment layer 19 is formed of a polyimide film, Sl02, or the like.

Protective film l to protect TFT6 and 7, bus wiring, etc.
The appropriate thickness of 7 is about 2000A to 10000A, but in this embodiment, it is set to about 5000A as described above. The base insulating film l1 and the protective film l7 are SiN
In addition to ×, it may be formed of SjOx, Ta 206, A1203, or other oxides or nitrides. Protective film l
7 is not formed on the entire surface of the substrate, but has a main TFT 6 and a spare TFT 7.
, covering only parts that are not directly involved in display, such as bus wiring,
A window may be formed in which the central portion of the picture element electrode 5 is removed. The active matosox substrate produced in this example is:
It has the above structure.

Next, a color filter 21, a counter electrode 22, and an alignment layer 23 are formed in an overlapping manner on the other glass substrate 20 that faces the glass substrate 1 having the picture element electrode 5 formed thereon. Around the color filter 2l, a brano matrix (
(not shown) is provided.

Twisted nematic branched crystal molecules 18 are sealed between the pair of glass substrates 1 and 20 as a display medium. The orientation of the liquid crystal molecules 18 is changed in response to the voltage applied between the picture element electrode 5 and the counter electrode 22, and optical modulation is performed. This optical modulation is visually recognized as a display pattern.

A driving voltage is applied to all the pixel electrodes 5 from all the gate bus lines 3 and source bus lines 4 of the liquid crystal display device having the above configuration via the main TFT 6 . In a state where all the pixel electrodes are driven in this manner, pixel defects are easily visible. If a pixel defect occurs due to a defect in the main TFT 6, it can be easily corrected using the connecting portion 25.

FIG. 2 shows a cross-sectional view of the connecting portion 25 used to correct pixel defects. As shown by the arrow 26 in FIG. 2, the joint metal layer 24 is irradiated with laser light, infrared rays, electron beams, or other energy from the outside through the lower glass substrate 1. In this example, YAG laser light was used. When the branch wiring 8, the base insulation film l1, and the joint metal layer 24 overlap, when the laser beam is irradiated, dielectric breakdown of the base insulation film l1 occurs, and the branch wiring 8 and the joint metal layer 24 are melted and connected to each other. It becomes conductive. Similarly, in the M tatami part between the source electrode extension end 8a, the base insulating film l1, and the joint metal layer 24,
Dielectric breakdown of the base insulating film l1 occurs, and the source electrode extension end 8a and the joint metal layer 24 are fused and connected to each other and become electrically conductive. In this way, the branch wiring 8 and the source electrode extension end 8a are electrically connected via the joint metal layer 24,
Even if the preliminary TFT 7 is driven by the source bus wiring 1114 and the preliminary TFT 7 is connected to the picture element electrode 5, if the display operation of the picture element electrode 5 is performed with the defective main TFT 6 connected, the picture element The electrode 5 may not be able to perform a normal display operation. In order to eliminate such malfunction, the main TFT 6 is separated by laser light. The position cut by the laser beam is either the drain electrode l6 or the source electrode l5. The drain electrode 16 and the source electrode 15 include
As shown in FIG. IA mentioned above, a small width portion is provided, and furthermore, a cut arrow portion is provided in the pixel electrode 5 near the drain electrode 16, so that the metal etc. melted by laser beam irradiation can be reused. It will not stick and cause insufficient cutting.

Which of the drain electrode 16 and the source electrode 15 should be cut depends on what kind of defect has occurred in the main TFT 6. If only the source electrode l5 is cut, the branch wiring 8
The source signal from is never applied to the main TFT 6. However, since the main TFT 6 is connected to the picture element electrode 5, the voltage of the picture element electrode 5 remains as a parasitic capacitance between the drain electrode l6 and the gate electrode 9 of the main TFT 6.

Due to this parasitic capacitance, the display operation of the picture element electrode 5 is delayed,
And it may be incomplete.

By cutting only the drain electrode 16, the above-mentioned problem of parasitic capacitance is solved. However, if there is an insulation failure in the main TFT 6, the source signal of the branch wiring 8 will be transferred to the main TFT 6.
It will leak through.

If both the source electrode 15 and the drain electrode 16 are cut, the above problem can be completely solved, but this is not preferable because it complicates the repair process and leads to build-up. In this embodiment, the drain electrode l6 of the defective main TFT 6 is cut off, and the source electrode 15 is also cut off if necessary. With the above modification, the picture element electrode 5 is normally driven by the preliminary TFT 7.

In this embodiment, the laser beam was irradiated from the glass substrate 1 side, but the laser beam may be irradiated from any substrate side as long as the substrate allows the laser beam to pass through. Even if pixel defects are repaired using laser light in this way, since the protective film l7 is formed above the connection part 25, molten metal will not enter the liquid crystal layer which is the display medium. doesn't happen. Further, although the liquid crystal layer near the portion irradiated with the laser beam becomes cloudy, this cloudiness disappears and the original state is restored, so that there is no deterioration in image quality.

If high-quality laser light is irradiated or the laser light irradiation time is prolonged, the protective film 17 and even the alignment layer 19 may be discolored or destroyed, resulting in holes. but,
Since the portion irradiated with the laser beam is a minute area, it does not adversely affect the display. That is, when the protective film 17 and the alignment layer 19 are destroyed, fine particles of metal etc. dissolved by the laser beam irradiation are mixed into the liquid crystal layer and the liquid crystal layer is contaminated. It has been experimentally confirmed that the liquid crystal layer is not widely diffused from the vicinity of the liquid crystal layer to the liquid crystal layer. Therefore, contamination of the crystalline layer occurs only in a limited area near the laser beam irradiation area, and does not substantially adversely affect image quality.

FIG. 3A shows an example of an active matrix substrate forming a display device manufactured by the manufacturing method of the present invention. In this embodiment, the positions of the main TFT 6 and the spare TFT 7 are formed opposite to those of the embodiment shown in FIG. IA. and,
The connecting portion 25 is connected to the joint metal layer 24 and the joint metal layer 24
It is formed by the branch wiring 8 and the source electrode extension end 8a which are overlapped with each other with the base insulating film 11 interposed therebetween. Connection part 2
5, the source electrode extension end 8a is connected to the branch wiring 8 in a non-conducting state.
is opposed to. Therefore, among the main TFTs 6 and 7,
Only the main TFT 6 is electrically connected to the source bus wiring 4, and the pre-TFT 7 is not connected to the source bus wiring 4.

In the case of this embodiment as well, as in the embodiment of FIG.
By irradiating the main TFT 5 with laser light or the like and separating the main TFT 6 with the laser light, pixel defects caused by defects in the main TFT 6 are corrected.

FIG. 3B shows an example of an active matrix substrate forming a display device manufactured by the manufacturing method of the present invention. In this embodiment, the main TFT 6 is placed at the same position as in FIG.
and a pre-I TFT 7 are formed, and the main TFT 6 is connected to the source bus wiring 4 by a branch wiring 8. The joint metal layer 24 is formed below the source bus wiring 4. The connection portion 25 is formed by the joint metal layer 24, the source bus wiring 4 and the source electrode extension end 8a superimposed on the joint metal layer 24 with the base insulating film 11 interposed therebetween. In the connecting portion 25, the source electrode extension 8a is opposed to the source bus wiring 4 in a non-conductive state.

Therefore, among the main TFT 6 and the spare TFT 7, the main TFT
6 is electrically connected to the source bus wiring 4, and the spare T
FT7 is not connected to the source bus wiring 4.

In this embodiment, similarly to the example shown in FIG. be done.

In the above embodiment, the main TFT 6 and the spare TFT 7 are arranged side by side on the gate bus wiring 3 and connected to the same side of the picture element electrode 5, but they may be connected to different sides of the picture element electrode 5.

The structure of the connecting portion 25 may be the structure shown in FIG. 4 or FIG. 5 in addition to the structure of the above embodiment. In the configuration shown in FIG. 4, a through hole 27 is provided in the base insulating film 11, and the joint metal layer 24 and the source electrode extension end 8a are electrically connected in advance. If a defect occurs in the main TFT 6, only the overlapping portion of the branch wiring 8 and the joint metal layer 24 is connected using optical energy. In the structure shown in FIG. 5, the joint metal layer 24 is not provided, and the source electrode extension end 8a is placed directly above the branch wiring 8 with the base insulating film 1l interposed therebetween. If a defect occurs in the main TFT 6, the source electrode extension end 8a and the branch wiring 8 are directly fused and connected by light energy irradiation.

In FIG. 4, the through hole 27 may be provided on the side of the branch wiring 8, and the branch wiring 8 and the joint metal layer 24 may be connected in advance. In this configuration, only the overlapping portion of the source electrode extension end 8a and the joint metal layer 24 is connected by laser beam irradiation. Further, in FIG. 5, a configuration may be adopted in which the branch wiring 8 is formed on the source electrode extension end 8a via the base insulating film 1l. Furthermore, in any of the embodiments, the base coat film 2 is not necessarily provided and can be omitted.

Although each of the above embodiments describes a method for manufacturing a transmissive liquid crystal display device, the present invention can be similarly applied to manufacturing a reflective display device. Further, in the above embodiment, a method for manufacturing an active matrix liquid crystal display device using TPT as a switching element has been described, but the present invention is not limited thereto. The present invention is also applicable to manufacturing a wide range of display devices using various switching elements such as MTM elements, diodes, and varistors. Furthermore, it can be applied to the manufacture of various display devices using thin film light emitting layers, dispersed EL light emitting layers, plasma light emitters, etc. as display media.

(Effects of the Invention) According to the method for manufacturing an active matrix display device of the present invention, it is possible to easily identify the location where a pixel defect occurs, and if the pixel defect is due to a defective switching element, this can be detected in the display device. Since it can be easily modified from the outside, display devices can be manufactured with high yield. Therefore, it can contribute to cost reduction as a display device.

4. Oh no! 1 FIG. 1A is a plan view of an example of an active matrix substrate constituting a display device manufactured by the manufacturing method of the present invention;
FIGS. IB and IC are cross-sectional views of the display device shown in FIG. 1A taken along lines B-B and C-C in FIG. 3A and 3B are plan views of an active matrix substrate constituting another display device manufactured by the manufacturing method of the present invention, and FIGS. 4 and 5 are cross-sectional views of the connecting portion used. It is a sectional view showing an example of a pond.

1, 20...Glass substrate, 3...Gate bus wiring,
4... Source bus wiring, 5... Picture element electrode, 6...
Main TFT, 7... Spare TFT, 8... Branch wiring, 8a
Source electrode extension end, 9... Gate electrode, 11... Base insulating film, +5, 15a... Source electrode, 16.1
6a...Drain electrode, l7...Protective film, 18...
- Liquid crystal molecules, 19, 23... Orientation layer, 2l... Color filter, 22... Counter electrode, 24... Joint metal layer, 25... Connection portion.

Below Up

Claims (1)

[Claims] 1. An active matrix display device comprising a pair of substrates, at least one of which is translucent, and a display medium inserted between the substrates and whose optical characteristics are modulated in response to an applied voltage. In the manufacturing method, picture element electrodes are arranged in a matrix on the inner surface of one of the pair of substrates, and a main switching element and a preliminary switching element are respectively electrically connected to the picture element electrodes. , a scanning line connected to the main switching element and the auxiliary switching element, a signal line connected to the main switching element, an extended end of the signal input terminal of the auxiliary switching element, and a branched line from the signal line. a step of forming a connection portion in which the branch wiring is disposed in close proximity to the branch wiring in a non-conducting state with at least an insulating film interposed therebetween; a step of forming a counter electrode on the other substrate of the pair of substrates; and a step of forming a counter electrode between the pair of substrates. a step of enclosing the display medium; a step of applying a driving voltage to the display medium via the picture element electrode and the counter electrode to detect a picture element defect; and the picture element in which the picture element defect has been detected. Energy is irradiated to the connecting portion where the extended end of the signal input terminal of the preliminary switching element connected to the electrode and the branch wiring are opposed to each other, thereby connecting the preliminary switching element and the signal line to the connecting portion. a wiring part between the main switching element and the signal line, and a wiring part between the main switching element and the picture element electrode. A method for manufacturing an active matrix display device, comprising: irradiating energy to cut the wiring portion. 2. A method for manufacturing an active matrix display device including a pair of substrates, at least one of which is translucent, and a display medium inserted between the substrates and whose optical characteristics are modulated in response to an applied voltage. , a picture element electrode arranged in a matrix on the inner surface of one of the pair of substrates, a main switching element and a preliminary switching element each electrically connected to the picture element electrode, and the main switching element. A scanning line connected to the auxiliary switching element, a signal line connected to the main switching element, an extended end of the signal input terminal of the auxiliary switching element, and the signal line are connected to each other through at least an insulating film. a step of forming a connecting portion that is disposed in close proximity to each other in a conductive state; a step of forming a counter electrode on the other of the pair of substrates; a step of enclosing the display medium between the pair of substrates; A step of applying a driving voltage to the display medium via the element electrode and the counter electrode to detect a pixel defect; and a signal of the preliminary switching element connected to the pixel electrode in which the pixel defect has been detected. irradiating energy to the connecting portion where the extended end of the input terminal and the signal line are opposed to electrically connect the preliminary switching element and the signal line via the direct reading portion; , irradiating energy to one of the wiring portions between the main switching element and the signal line, and the wiring portion between the main switching element and the picture element electrodes to strengthen the wiring portion. A method of manufacturing an active matrix display device, comprising: cutting the active matrix display device.