JPH0786616B2 - Manufacturing method of active matrix display device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a display device that performs display by applying a drive signal to a display pixel electrode via a switching element, and more particularly to a pixel electrode. The present invention relates to a method for manufacturing a display device of an active matrix drive system, in which pixels are arranged in a matrix to perform high density display.

(Prior Art) Conventionally, in a liquid crystal display device, an EL display device, a plasma display device, etc., a display pattern is formed on a screen by selecting display pixels arranged in a matrix. . As a method of selecting display picture elements, there is an active matrix driving method in which individual picture element electrodes are arranged and a switching element is connected to each of the picture element electrodes to perform display driving. This system is capable of high-contrast display and has been put to practical use in liquid crystal televisions, word processors, terminal display devices of computers, and the like. As a switching element for selectively driving the pixel electrode, a TFT (thin film transistor) element, a MIM (metal-insulating layer-metal) element, a MOS transistor element, a diode, a varistor, etc. are generally known. By switching the voltage applied between the picture element electrode and the counter electrode facing the picture element electrode, the display medium such as liquid crystal, EL light emitting layer or plasma light emitter interposed therebetween is optically modulated. This optical modulation is visually recognized as a display pattern.

(Problems to be Solved by the Invention) When a switching element is connected to a pixel electrode for high-density display, it is necessary to arrange a large number of pixel electrodes and switching elements. However, the switching element may be formed as a malfunctioning element when it is manufactured on the substrate. A pixel electrode connected to such a defective element causes a pixel defect that does not contribute to display. The occurrence of the picture element defect causes a large decrease in the manufacturing yield, which is a serious problem in manufacturing. Therefore, studies are being made on a technique for later correcting the generated picture element defects.

As a technique for repairing picture element defects, a plurality of switching elements are provided for each picture element electrode, and only one switching element is used as a picture element electrode, as disclosed in JP-A-61-153619. If the switching element connected to the picture element electrode is defective, the switching element and the picture element electrode are cut by a laser trimmer, an ultrasonic cutter, or the like,
A technique for connecting another switching element to a pixel electrode has been proposed. Further, as a means for connecting the switching element and the pixel electrode in this case, a technique of attaching a minute conductor with a dispenser or the like, and a technique of coating Au, Al or the like on a predetermined portion on a substrate are exemplified. Further, JP-A-61-56
Japanese Patent Laid-Open No. 382 and Japanese Patent Laid-Open No. 59-101693 disclose a technique of electrically connecting metal layers by irradiating a laser beam to melt a metal.

However, the above-mentioned conventional defect repairing technique is a system in which after detecting a defect, the metal is evaporated and redeposited or locally melted by laser irradiation to electrically connect the metal. That is, it must be used in the process of manufacturing the active matrix substrate before assembling the display panel. The reason is that after the display panel is completed, a part of the metal evaporated or melted by laser light irradiation is mixed in the display medium such as liquid crystal interposed between the pixel electrode and the counter electrode, and the display medium This significantly deteriorates the optical characteristics of. Therefore, any of the conventional pixel defect repair techniques described above is applied to the active matrix substrate manufacturing process before the display panel is assembled, that is, before the display medium is inserted.

However, it is extremely difficult to detect this defect at the manufacturing stage of the active matrix substrate. Especially the number of picture elements
In a large panel with 100,000 to 500,000 or more, in order to detect the electrical characteristics of all the pixel electrodes and detect defective switching elements, it is necessary to use extremely high-precision measuring equipment. Therefore, the inspection process becomes complicated, mass productivity is hindered, and the cost is increased.
Therefore, the above-mentioned technique cannot be applied to a large-sized display panel having a large number of picture elements.

In order to solve the above problems, a display device using an active matrix substrate shown in FIG. 5A is disclosed in Japanese Patent Application No. 63-3082.
A patent application has been filed as No. 31. By assembling a display device using this substrate, it is possible to identify the location of the pixel defect in the state of the display device and correct the pixel defect in the state of the display device. When an active matrix display device is assembled using this substrate, the line BB and the line C- in FIG. 5A are shown.
Sectional views along the line C are shown in FIGS. 5B and 5C, respectively. A base coat film 2 is formed on the entire surface of a glass substrate 1, on which gate bus lines 3 and source bus lines 4 are arranged in a grid pattern. A base insulating film 11 described later is interposed between the gate bus wiring 3 and the source bus wiring 4. In a rectangular area surrounded by the gate bus wiring 3 and the source bus wiring 4, picture element electrodes 5 made of a transparent conductive film (ITO) are arranged to form a matrix pattern. A TFT 6 is arranged near the corner of the picture element electrode 5, and the TFT 6 and the picture element electrode 5 are electrically connected by a drain electrode 16. In addition, a spare TFT7 is provided near the other corner of the pixel electrode.
Are arranged, and the spare TFT 7 and the pixel electrode 5 are opposed to each other in a non-conductive state. The TFT 6 and the spare TFT 7 are arranged side by side on the gate bus line 3 and connected to the source bus line 4 by a branch line 8.

Figure 5B shows the structure around TFT6. A gate electrode 9 formed on a part of the gate bus line 3 and a gate insulating film 10 obtained by anodizing the surface of the gate electrode 9 are formed.
From above, a base insulating film 11 also serving as a gate insulating film, an intrinsic semiconductor layer 1 made of amorphous silicon (a-Si)
2, a semiconductor protective film 13 for protecting the upper surface of the intrinsic semiconductor layer 12,
An n-type semiconductor layer 14 for sequentially forming ohmic contact with the source electrode and the drain electrode is sequentially laminated. Next, a source electrode 15 connected to the branch wiring 8 and a drain electrode 16 connected to the pixel electrode 5 are formed. TFT6
Further, the protective film 17 is covered almost all over the upper surface of the pixel electrode 5 and the alignment layer 19 is further deposited thereon.

On the inner surface of the other glass substrate 20 facing the glass substrate 1, a color film layer 21, a counter electrode 22, and an alignment layer 23 are formed in an overlapping manner. Liquid crystal molecules 18 are enclosed as a display medium between the pair of glass substrates 1 and 20.

Figure 5C shows the configuration near the spare TFT7. The structure of the spare TFT 7 is the same as that of the TFT 6 described above. A joint metal layer 24 is formed in an island shape on the base coat film 2 which is separated from the gate electrode 9 by a predetermined distance. The base insulating film 11 is deposited on the joint metal layer 24, and the extended end 16a of the drain electrode 16 of the spare TFT 7 is placed on the base insulating film 11. Further, the end portion of the pixel electrode 5 is laminated on the base insulating film 11 on the joint metal layer 24 together with the metal piece 25. Therefore, the extended end 16a and the pixel electrode 5
And maintain a non-conducting state. The extended end 16a of the drain electrode 16 and the end of the pixel electrode of the metal piece 25 are completely covered with the protective film 17.

If the liquid crystal display device having the above structure is driven over the entire surface, the TFT6
If the pixel is defective, the pixel defect is easily visually recognized. In such a case, the overlapping portion of the extended end 16a and the joint metal layer 24,
Further, the overlapping portion of the metal piece 25 and the joint metal layer 24 is irradiated with laser light or the like. The extended end 16a, the base insulating film 11, and the joint metal layer 24 are mutually melted by the laser light, and the interlayer insulating layer is dielectrically broken down to be in a conductive state. Similarly, the metal piece 25 on the pixel electrode 5 side and the joint metal layer 24 are also in a conductive state. In this way, the spare TFT 7 and the pixel electrode 5 can be electrically connected. The laser light is emitted from the glass substrate 1 or
Irradiated through 20. At this time, the joint metal layer 24, the extension end
Since the protective film 17 is formed above the 16a and the metal piece 25, the molten metal does not mix into the liquid crystal which is the display medium.

Even if the spare TFT 7 is connected in this way, it is necessary to separate the TFT 6 from the pixel electrode 5 if the TFT 6 has poor insulation or the like. This cutting is performed by irradiating the drain electrode 16 with laser light or the like to cut the drain electrode 16.
An enlarged view of the portion where the TFT 6 and the pixel electrode 5 of FIG. 5A are connected is shown in FIG. 5D. The laser beam is applied to the region indicated by S in FIG. 5D, and the drain electrode 16 is cut off.

However, even if the laser light is irradiated in this way, if the distance Y between the pixel electrode 5 and the gate bus wiring 3 is small, the molten and diffused metal adheres to the pixel electrode 5 and the gate bus wiring 3. As a result, the drain electrode may not be electrically disconnected. In such a case, the pixel defect cannot be corrected. To avoid this situation,
It is conceivable to increase the distance Y between the pixel electrode 5 and the gate bus line 3. However, if the distance Y is increased, the aperture ratio of the active matrix substrate decreases, and a new problem occurs that the entire display screen becomes dark.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a method of manufacturing an active matrix display device having a high manufacturing yield and a small decrease in aperture ratio. is there.

(Means for Solving the Problem) In the method for manufacturing an active matrix display device according to the present invention, at least one is sandwiched between a pair of substrates having a light-transmitting property, and optical characteristics are modulated in response to an applied voltage. In a method of manufacturing an active matrix display device including a display medium, a pixel electrode having a cutout portion arranged in a matrix on the inner surface of one of the pair of substrates, and the cutout portion. A switching element that is electrically connected to the picture element electrode in the vicinity and has a connection end in which the width of the portion located in the cutout portion is smaller than the other portion, and the picture element electrode are placed close to each other in a non-conductive state. And a connecting portion where the extended portion of the preliminary switching element and the pixel electrode face each other with at least an insulating layer interposed therebetween. The manufacturing method also includes a step of covering the connection portion with an insulating protective film, a step of forming a counter electrode on the other substrate of the pair of substrates, a step of inserting the display medium between the pair of substrates, and A step of applying a drive signal to the display medium through the element electrode and the counter electrode to optically detect a defect of the switching element; a pixel electrode connected to the switching element in which the defect is detected; A step of electrically connecting the pixel electrode and the preliminary switching element by irradiating light energy to the connection portion with the preliminary switching element that is adjacent to the pixel electrode, and the switching element in which a defect is detected A step of electrically disconnecting the picture element electrode and the switching element by irradiating the connection end with light energy at the cutout portion of the picture element electrode connected to the. Thereby, the above object is achieved.

(Operation) In the present invention, in addition to the switching element electrically connected to the pixel electrode, a preliminary switching element that can be connected to the switching element is formed, and the preliminary switching element and the pixel electrode are connected to each other. Since the connecting portion for connection is covered with the insulating protective film, by irradiation of the laser light on the connecting portion after the display panel is assembled,
It is possible to repair the defects of the picture elements without inviting the molten metal into the liquid crystal, and it is possible to improve the manufacturing yield of the display device.

Further, since the picture element electrode has a notch in the vicinity of the portion to which the connection end of the switching element is connected, the switching element and the picture element electrode are provided between the picture element electrode and the peripheral wiring. The space that can be secured for the fusing of the pixel electrodes can be made smaller, and the width of the part located inside the notch part of the pixel electrode at the connection end with the pixel electrode is smaller than the width of the other part as a switching element. Since it is formed, it is possible to reduce the opening width of the notch formed in the pixel electrode and suppress a decrease in the aperture ratio of the active matrix substrate.

(Examples) The present invention will be described below with reference to Examples. FIG. 1A shows a substrate of an active matrix display device manufactured by the manufacturing method of the present invention. The configuration of the cross-sectional view taken along the line bb and the line cc of FIG. 1A of this display device is similar to the configuration shown in FIGS. 5B and 5C, and therefore, in the following description, those configurations will be described. This will be done with reference to the drawings. Ta ₂ O ₅ , Al on glass substrate
_The base coat film 2 made of ₂ O ₃ or Si ₃ N ₄ has a thickness of 3000
Å ~ 9000Å, the gate bus wiring 3 for supplying scanning signals and the source wiring 4 for supplying data signals
And are arranged in a grid. The gate bus wiring 3 is generally formed of a single-layer or multi-layer metal such as Ta, Al, Ti, Ni and Mo, but Ta is used in this embodiment. The source bus line 4 is also made of the same metal, but Ti is used in this embodiment. A base insulating film 11, which will be described later, is interposed at the intersection of the gate bus wiring 3 and the source bus wiring 4. In a rectangular area surrounded by the gate bus wiring 3 and the source bus wiring 4, picture element electrodes 5 made of a transparent conductive film (ITO) are arranged to form a matrix picture element pattern.
A TFT 6 is arranged near the corner of the picture element electrode 5, and the TFT 6 and the picture element electrode 5 are electrically connected by a drain electrode 16. An enlarged view of the portion where the drain electrode 16 and the pixel electrode 5 are connected is shown in FIG. 1B. The drain electrode 16 is drawn laterally from above the gate electrode 9 in the direction of the pixel electrode 5, and has a narrow width in a portion away from above the gate electrode 9. A rectangular cutout 5a is provided in the portion of the pixel electrode 5 close to the drain electrode. The notched portion 5a is formed in the portion where the width of the drain electrode 16 is narrowed.
Is connected to the pixel electrode 5 in the vicinity of the side farthest from the TFT 6. In addition, in the vicinity of the other corners of the pixel electrode 5, a spare
The TFT 7 is arranged, and the spare TFT 7 and the pixel electrode 5 are placed opposite to each other in a non-conductive state. TFT6 and spare TFT7 are gate bus wiring 3
They are arranged in parallel on the upper side and are connected to the source bus line 4 by a branch line 8.

Ta gate electrode 9 formed on a part of the gate bus line 3 and Ta ₂ O ₅ obtained by anodizing the surface of the gate electrode 9.
A gate insulating film 10 made of is formed. From above, SiN _X (eg Si
₃ N ₄ ) Base insulating film 11, a-Si intrinsic semiconductor layer 12, semiconductor protective film 1 made of SiN _x for protecting the upper surface of the intrinsic semiconductor layer 12
3. An n-type semiconductor layer 14 made of a-Si is sequentially stacked to obtain ohmic contact with the source electrode and the drain electrode. A source electrode 15 connected to the branch wiring 8 and a drain electrode 16 connected to the pixel electrode 5 are formed on the n-type semiconductor layer 14. The source electrode 15 and the drain electrode 16 are made of Ti, Ni, Al or the like. Drain electrode 16
The pixel electrode 5 connected to the end portion of is patterned on the base insulating film 11. The thickness of the base insulating film 11 is 1500Å ~
About 6000Å is suitable, but in this embodiment 2000Å-3500
It is set to Å. A protective film 17 made of SiN _x covers almost the entire upper surface of the TFT 6 and the pixel electrode 5, and an alignment layer 19 for controlling the alignment of liquid crystal molecules 18 is deposited on the protective film 17. The alignment layer 19 is made of SiO ₂ , polyimide resin, or the like. A suitable thickness of the protective film 17 is about 2000Å-10000Å, but in this embodiment, it is set to about 5000Å. As the base insulating film 11 and the protective film 17, other than SiN _x , SiO _x , Ta
Oxides and nitrides such as ₂ O ₅ and Al ₂ O ₃ can be used.
The protective film 17 may have a windowed structure removed at the central portion of the pixel electrode 5 instead of covering the entire surface.

On the inner surface of the other glass substrate 20 facing the glass substrate 1 on which the pixel electrodes 5 are formed, a color filter layer 21, a counter electrode 22 facing the pixel electrodes 5, and an alignment layer 23 are formed in an overlapping manner. . A black matrix (not shown) is provided around the color filter layer 21 as needed.

Between the pair of glass substrates 1 and 20 as a display medium,
Twisted nematic liquid crystal molecules 18 that are twisted and aligned are encapsulated, and the orientation is converted in response to the voltage application between the pixel electrode 5 and the counter electrode 22, whereby optical modulation is performed.

The structure of the spare TFT 7 is the same as that of the TFT 6 described above. A joint metal layer 24 is formed in an island shape on the base coat film 2 which is separated from the gate electrode 9 by a predetermined distance. This joint metal layer 24 is
Like the gate electrode, it is made of Ti, Ni, Al, Ta, or the like, and can be patterned at the same time when the gate electrode 9 is formed. The above-described base insulating film 11 is deposited on the joint metal layer 24, and the extended end 16a of the drain electrode 16 of the spare TFT 7 is formed on the base insulating film 11.
Is placed. Further, the end portion of the pixel electrode 5 is laminated on the base insulating film 11 on the joint metal layer 24 together with the metal piece 25. Therefore, the extended end 16a and the pixel electrode 5 are separated from each other, and the non-conductive state is maintained. The metal piece 25 is T
It consists of i, Al, Ni, or Ta. The extended end 1 of the drain electrode 16
The pixel electrode ends of 6a and the metal piece 25 are completely covered with the protective film 17. Joint metal layer 24 and drain electrode extension end
The base insulating film 11 located between the 16a and the metal piece 25 is
It works as an interlayer insulator between upper and lower metals, and its thickness is 1000Å
Approximately 7,000 Å is suitable, but in this embodiment, since the base insulating film 11 which also serves as the gate insulating film of the TFT is used,
It is set to 2000Å to 3500Å. The drain electrode extension end 16a and the protective film 17 on the metal piece 25 are for electrically connecting the liquid crystal molecules which are the display medium to each other in a separated state, and approximately 1500Å to 15000Å are suitable. However, since the TFT protective film is used in this embodiment,
Å Set before and after.

A driving voltage is applied to all the pixel electrodes 5 from all the lines of the gate bus wiring 3 and the source bus wiring 4 of the liquid crystal display device having the above structure through the TFT 6 to drive the entire display device. In such a state of the display device, when the TFT 6 is defective, the pixel defect is easily visually recognized. In the detected pixel defect portion, as shown by an arrow in FIG. 2, laser light, infrared rays, an electron beam or other heat rays are externally applied to the joint metal layer through the lower glass substrate 1 or the upper glass substrate 20. Irradiated to 24. In this embodiment, YAG laser light is used. When the laser light is irradiated, the extended end 16a, the base insulating film 11, and the joint metal layer 24 are melted with each other, and the interlayer insulating layer is dielectrically broken down to be in a conductive state. Similarly, also between the metal piece 25 on the pixel electrode 5 side and the joint metal layer 24, when they are irradiated with laser light, they are melted and contacted with each other to be in a conductive state. In this way, the spare TFT 7 and the pixel electrode 5 are electrically connected. At this time, the joint metal layer 24,
Since the protective film 17 is formed above the extended end 16a and the metal piece 25, the molten metal does not mix into the liquid crystal that is the display medium. The protective film 17 is a transparent insulator and allows laser light to pass therethrough. Therefore, the laser light is absorbed by the metal material and instantly heats and melts it. Therefore, at the time of laser light irradiation, the metal material and the interlayer insulating film sandwiched by the metal material are melted and mixed with each other, but the protective film 17 is not destroyed.
It was also confirmed that the liquid crystal layer irradiated with the laser light became cloudy at the irradiated part, but this cloudiness eventually disappeared and was restored to the original alignment state.

When it is necessary to separate the TFT 6 from the pixel electrode 5 due to poor insulation of the TFT 6, the drain electrode 16 of the TFT 6 needs to be cut by laser light or the like. In this embodiment, since the drain electrode 16 and the picture element electrode 5 having the shapes shown in FIG. 1B are formed, the TFT 6 can be easily separated from the picture element electrode 5 by irradiating the R portion with laser light. You can In addition, the distance X between the pixel electrode 5 and the drain electrode 16 shown in FIG. 1B is set to 5 μm or more, so that the drain electrode 16 and the pixel electrode 5 are electrically complete when the laser light is irradiated. It was confirmed that it can be cut into.

The arrangement structure of the spare TFT 7 and the pixel electrode 5 may be the structure shown in FIG. 3 or 4 other than the above. In FIG. 3, a through hole is formed in the base insulating film 11 in advance, and the joint metal layer 24 is formed.
And the metal piece 25 are connected, and when the TFT6 is defective, the spare TFT7
Only the drain electrode extension end 16a and the joint metal layer 24 are electrically connected by light energy. Further, FIG. 4 shows that the drain electrode extension end of the spare TFT 7 is not provided with the joint metal layer 24.
16a is arranged directly below the metal piece 25 via the base insulating film 11, and both are directly fused and connected by light energy irradiation. In FIGS. 3 and 4, it is clear that the drain electrode extension end 16a and the metal piece 25 may be formed in an inverse relationship to each other. Further, as the display panel substrate, at least one of the substrates needs to use a member having a light-transmitting property (glass, plastic, etc.) in order to enable laser irradiation, but the base coat film 2 is not always necessary and is not provided. May be. As described above, in this embodiment, in addition to the TFT 6 electrically connected to the pixel electrode 5, a spare TFT 7 that can be reconnected to the TFT 6 is formed, and the spare TFT 7 and the pixel electrode 5 are connected. Since the connection portion for, that is, the joint metal layer 24, the drain electrode extended end 16a, the metal piece 25 so as to be covered by the protective film 17, by the laser light irradiation to the connection portion after the assembly of the display panel, The defect repair of the picture element can be performed without inviting the melted metal into the liquid crystal.

Further, since the pixel electrode 5 having the notch 5a in the vicinity of the portion to which the connection end (drain electrode) 16 of the TFT 6 is connected is formed, the pixel electrode 5 and the gate bus wiring 3 are formed.
The space secured for fusing between the TFT 6 and the pixel electrode 5 can be made small, and as the TFT 6, the cutout portion 5a of the pixel electrode 5 at the connection end (drain electrode) 16 with the pixel electrode 5 is formed.
Since the width of the portion located inside is smaller than the width of the other portion, the opening width of the notch portion 5a formed in the pixel electrode 5 is reduced to reduce the aperture ratio of the active matrix substrate. A display device with low resistance can be obtained.

Although the manufacturing method of the active matrix type liquid crystal display device has been described in the above embodiment, the present invention is not limited to this, and a wide range for obtaining a display pattern by using various switching elements such as MIM element, diode, varistor, etc. It can be applied to the method for manufacturing a liquid crystal display element. Further, it can be applied to a manufacturing method of various display devices using a thin film light emitting layer, a dispersion type EL light emitting layer, a plasma light emitting body or the like as a display medium.

(Effects of the Invention) As described above, according to the manufacturing method of the active matrix display device of the present invention, in addition to the switching element electrically connected to the pixel electrode, a spare that can be reconnected to the switching element is provided. Since the switching element is formed and the connecting portion for connecting the preliminary switching element and the pixel electrode is covered with the insulating protective film,
By irradiating the connecting portion with laser light after assembling the display panel, it is possible to repair the defects of the picture element without inviting the molten metal into the liquid crystal. In other words, the picture element defect can be reliably repaired in the state of the display device that can easily identify the picture element defective portion visually, the manufacturing yield of the display device is improved, the mass productivity is secured, and the display device is The cost can be reduced.

Further, since the picture element electrode has a notch in the vicinity of the portion to which the connection end of the switching element is connected, the switching element and the picture element electrode are provided between the picture element electrode and the peripheral wiring. It is possible to reduce the space to be secured for fusing, and for the switching element, the width of the part located in the notch of the pixel electrode at the connection end with the pixel electrode is smaller than the width of the other part. Since it is formed, it is possible to obtain a display device in which the opening width of the notch portion formed by the pixel electrode is reduced and the reduction in the aperture ratio of the active matrix substrate is small.

[Brief description of drawings]

FIG. 1A is a plan view of an example of an active matrix substrate manufactured by the manufacturing method of the present invention, and FIG. 1B is a plan view of FIG. 1A.
Fig. 2 is an enlarged view of the vicinity of TFT6. Fig. 2 is a cross-sectional view showing how the pixel electrode 5 and the drain electrode extension end 16a are electrically connected by laser light. Figs. FIG. 5B is a cross-sectional view showing another example of the arrangement structure with the element electrodes 5, FIG. 5A is a cross-sectional view showing an example of an active matrix substrate having a configuration capable of correcting a pixel defect in a state in which a display device is assembled, FIG.
5A and 5C are cross-sectional views of a display device assembled using the active matrix substrate of FIG. 5A, taken along the planes along the lines BB and CC of FIG. 5A, and FIG. 5A
It is an enlarged view of the vicinity of TFT6 of the figure. 1,20 …… Glass substrate, 6 …… TFT, 7 …… Spare TFT, 9 ・ ・ ・
… Gate electrode, 11 …… Base insulating film, 15 …… Source electrode, 16 …… Drain electrode, 17 …… Protective film, 18 …… Liquid crystal molecule, 19,23 …… Alignment layer, 21 …… Color filter, 22 ......
Counter electrode.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroaki Kato 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (56) References JP 61-35483 (JP, A) JP Sho 64 -54417 (JP, A)

Claims (1)

[Claims] 1. A method of manufacturing an active matrix display device comprising a display medium, at least one of which is sandwiched between a pair of substrates having translucency and whose optical characteristics are modulated in response to an applied voltage. A pixel electrode having a notch portion, which is arranged in a matrix on the inner surface of one of the pair of substrates, and electrically connected to the pixel electrode in the vicinity of the notch portion, and the notch A switching element having a connection end in which the width of a portion located inside the portion is smaller than the other portion, a preliminary switching element that is disposed in proximity to the pixel electrode in a non-conducting state, an extension portion of the preliminary switching element, and A step of forming a connecting portion which is opposed to the pixel electrode through at least an insulating layer, a step of covering the connecting portion with an insulating protective film, a step of forming a counter electrode on the other substrate of the pair of substrates, The A step of inserting the display medium between a pair of substrates; a step of applying a drive signal to the display medium through the pixel electrode and the counter electrode to optically detect a defect of the switching element; The connection portion between the picture element electrode connected to the switching element and the preliminary switching element adjacent to the picture element electrode is irradiated with light energy to electrically connect the picture element electrode and the preliminary switching element. Step of electrically connecting, and at the cutout portion of the picture element electrode connected to the switching element where a defect is detected, the connection end is cut by light energy irradiation, and the picture element electrode and the switching element A method of manufacturing an active matrix display device including the step of electrically disconnecting and.