Active matrix substrate, display device, and motherboard

An active matrix substrate including a resin substrate including a plurality of external connection terminals arranged near a display region, the active matrix substrate includes: a plurality of first lead wires each extending from one of the external connection terminals to the display region; and a plurality of second lead wires each extending from one of the external connection terminals to a separation line, the second lead wires being arranged with an arrangement pitch along the separation line, and the arrangement pitch of the second lead wires being greater than an arrangement pitch of the first lead wires.

TECHNICAL FIELD

The disclosure relates to an active matrix substrate including a plurality of external connection terminals arranged near a display region, a display device, and a method for manufacturing the active matrix substrate.

BACKGROUND ART

A display device, such as an organic electroluminescence (EL) display device, includes many terminals near a display region. These terminals are connected to external connection substrates including a flexible printed circuit (FPC).

Until the terminals are connected to such a substrate as an FPC in the manufacturing process of the display device, the manufacturing steps proceed with these many terminals exposed near an active matrix substrate. Here, if the display device is, for example, a liquid crystal display device, a pixel drive element is broken by static caused in the rubbing of an alignment film that controls an alignment direction of liquid crystals. The broken drive element frequently causes faulty characteristics of the device.

Hence, Patent Document 1 discloses an array substrate 100 designed with a known technique. As illustrated in FIG. 13, all the terminals are connected to a conductor or a semiconductor referred to as a short ring 102, and short-circuited. The short ring 102 prevents damage caused by static produced in the manufacturing process. Note that, immediately before terminals 101 of the display device are connected to a not-shown external connection substrate, the short ring 102 is separated along a separation line SL from electrical leads 103 each extending from one of the terminals 101 to the short ring 102.

CITATION LIST

Patent Literature

SUMMARY

Technical Problem

Recent display devices such as organic EL display devices provide images with high definition, and that is why the terminal spacing and the electrical-lead spacing are set narrowly. The narrow spacing causes a problem below when the electrical leads are separated with, for example, a laser beam.

That is, when the electrical leads are connected to a known short ring, the electrical leads are arranged with a pitch distance between the terminals maintained. Hence, the electrical-lead spacing along the separation line is significantly narrow. The short ring can be physically separated on a glass substrate. On a flexible substrate made of such a material as polyimide, however, the short ring is separated with, for example, a laser beam or a diamond cutter. In such a case, polyimide burns black to be carbon, becomes electrically conductive, and causes an electric leak between the terminals.

In view of the above known problem, an aspect of the disclosure is intended to provide an active matrix substrate, a display device, and a mother substrate capable of preventing a leak between terminals.

Solution to Problem

An active matrix substrate according to an aspect of the disclosure includes a resin substrate including a plurality of external connection terminals arranged near a display region. The active matrix substrate includes: a plurality of first lead wires each extending from one of the external connection terminals to the display region; and a plurality of second lead wires each extending from one of the external connection terminals to a separation line. The second lead wires are arranged with an arrangement pitch along the separation line, and the arrangement pitch of the second lead wires is greater than an arrangement pitch of the first lead wires.

A display apparatus according to an aspect of the disclosure includes the active matrix substrate. The separation line coincides with an end face of a display panel included in the display device.

A mother substrate according to an aspect of the disclosure includes a plurality of active matrix substrates planarly arranged and including the active matrix substrate.

Advantageous Effects of Disclosure

An aspect of the disclosure provides an active matrix substrate, a display device, and a mother substrate capable of preventing a leak between terminals.

DESCRIPTION OF EMBODIMENTS

First Embodiment

Described below is an embodiment of the disclosure, with reference toFIGS.1to4.

Basic Configuration of Display Region of Organic EL Substrate

Described below with reference toFIGS.2to4is a cross-sectional structure of a display panel40, of an organic EL display device1, including an active matrix substrate AMC1according to this embodiment.FIG.2is a cross-sectional view illustrating a configuration of a display region41, of an organic EL display device1, included in the display panel40.FIG.3(a), illustrating an end of the active matrix substrate of the organic EL display device1except the display region41, is a cross-sectional view of a first lead wire43aformed in the same layer as a gate terminal G is formed.FIG.3(b)is a cross-sectional view, taken along arrows A-A′ inFIG.3(a).FIG.4, illustrating an end of the active matrix substrate of the organic EL display device1except the display region41, is a cross-sectional view of a first lead wire43bformed in the same layer as a metal film formed to extend from a source electrode S and a drain electrode D.

As illustrated inFIG.2, the display region41of the display panel40includes from below: a resin substrate2; a barrier layer3acting as a second inorganic insulating film; a thin film transistor (TFT) layer10; a light-emitting element layer20; a sealing layer30; a bonding layer4; and a functional film5in the stated order.

The resin substrate2, the barrier layer3, and the TFT layer10constitute the active matrix substrate AMC1according to this embodiment.

As examples, materials of the resin substrate2include such resins as polyimide, epoxy, and polyamide. In this embodiment, polyimide is used.

When the display device is in use, the barrier layer3keeps water and impurities from reaching the TFT layer10and the light-emitting element layer20. An example of the barrier layer3can be a silicon oxide film or a silicon nitride film formed by the chemical-vapor deposition (CVD), or a multilayer film including those films.

The TFT layer10includes: a semiconductor film11; an inorganic insulating film12formed above the semiconductor film11; a gate electrode G formed above the inorganic insulating film12; an inorganic insulating film13formed above the gate electrode G; a not-shown capacitance line formed above the inorganic insulating film13; an inorganic insulating film14formed above the capacitance line; the source electrode S and the drain electrode D formed above the inorganic insulating film14; and a planarization film15formed above the source electrode S and the drain electrode D.

The semiconductor film11, the inorganic insulating film12acting as a gate insulating film, and the gate electrode G constitute a thin film transistor Td functioning as a light-emission control transistor. The source electrode S and the drain electrode D are respectively connected to a source region and a drain region of the semiconductor film11.

The semiconductor film11is formed of, for example, low-temperature polysilicon (LTPS) or an oxide semiconductor. Note that, inFIG.2, the TFT including the semiconductor film11as a channel is of a top gate structure. Alternatively, the TFT may be of a bottom gate structure when, for example, the channel of the TFT is an oxide semiconductor.

The inorganic insulating films12,13, and14can be, for example, a silicon oxide (SiOx) film, or a silicon nitride (SiNx) film formed by the CVD, or a multilayer film including these films. The planarization film15, functioning as an interlayer insulating film, may be made of applicable and light-sensitive organic materials such as polyimide and acrylic.

The gate electrode G, the source electrode S, the drain electrode D, and terminals are a monolayer metal film formed of at least one of such metals as aluminum (Al), tungsten (W), molybdenum (Mo), tantalum (Ta), chromium (Cr), titanium (Ti), and copper (Cu), or a multilayer metal film formed of these metals.

The light-emitting element layer20in this embodiment is, for example, an organic light-emitting diode (OLED) layer. The light-emitting element layer20includes: an anode electrode21formed above the planarization film15; a pixel bank22defining a sub-pixel of the display region41that the light-emitting element layer20overlaps; a light-emitting layer23formed above the anode electrode21; and a cathode electrode24formed above the light-emitting layer23. An OLED is formed to include the anode electrode21, the light-emitting layer23, and the cathode electrode24.

The pixel bank22covers an edge of the anode electrode21. The light-emitting layer23is formed, by vapor deposition or an ink jet method, in a light-emitting region surrounded with the pixel bank22. If the light-emitting element layer20is an OLED layer, for example, a hole-injection layer, a hole-transport layer, the light-emitting layer23, an electron-transport layer, and an electron-injection layer are stacked on top of another on a bottom face, of the pixel bank22, where the anode electrode21is exposed. Here, the layers other than the light-emitting layer23may be a common layer.

The anode electrode (a positive electrode)21includes, for example indium tin oxide (ITO) and an alloy containing silver (Ag) stacked on top of another. The anode electrode21reflects light. The cathode electrode24can be formed of a translucent conductive material such as ITO or indium zinc oxide (IZO).

If the light-emitting element layer20is the OLED layer, holes and electrons recombine together in the light-emitting layer23by a drive current between the anode electrode21and the cathode electrode24, which forms an exciton. While the exciton transforms to the ground state, light is released. Since the cathode electrode24is translucent and the anode electrode21is light-reflective, the light emitted from the light-emitting layer23travels upward. This is how the organic EL display device1is of a top emission type.

The light-emitting element layer20does not have to be formed of an OLED element. Alternatively, the light-emitting element layer20may be formed of an inorganic light-emitting diode or a quantum dot light-emitting diode.

The sealing layer30is formed above the light-emitting element layer20. The sealing layer30is translucent, and includes: an inorganic sealing film31covering the cathode electrode24of the light-emitting element layer20; an organic sealing film32formed above the inorganic sealing film31; and an inorganic sealing film33covering the organic sealing film32.

An example of the inorganic sealing films31and33can be a silicon oxide film, a silicon nitride film, or a silicon oxide nitride film formed by the chemical-vapor deposition (CVD) using a mask, or a multilayer film including these films.

The organic sealing film32is a light-transparent organic film thicker than the inorganic sealing films31and33, and may be made of applicable and light-sensitive organic materials such as polyimide and acrylic. For example, ink containing such an organic material is applied to the inorganic sealing film31by an ink jet technique, and cured with an ultraviolet ray.

Hence, the sealing layer30covers the light-emitting element layer20, and prevents such foreign objects as water and oxygen from penetrating into the light-emitting element layer20.

The functional film5has such functions as optical compensation, touch sensing, and protection. The functional film5is bonded with the bonding layer4.

Configuration of End of Active Matrix Substrate and Frame Region of Display Panel

The display panel40includes a frame region42and the active matrix substrate AMC1both having an end provided with a first lead wire43extending from internal wiring of the display region41, as illustrated inFIG.3. That is, the first lead wire43is electrically connected to various kinds of the internal wiring in the TFT layer10illustrated inFIG.2. Hence, the first lead wire43includes two kinds of wires for the sake of the manufacturing steps; namely, a first lead wire43aand a first lead wire43b, depending on which internal wire in the TFT layer10the first lead wire43is connected to.

Specifically, for example, the first lead wire43ais connected to a not-shown gate wire provided in the display region41and connected to the gate electrode G. As illustrated inFIG.3, the first lead wire43aincludes: an internal lead wire DW; a relay wire LW; and a terminal wire TW.

The internal lead wire DW is formed to extend from the not-shown gate wire. The relay wire LW and the terminal wire TW are formed in the same step as the gate electrode G, and the gate wire are formed. Hence, the internal lead wire DW, the relay wire LW, and the terminal wire TW are made of the same material as the gate electrode G is made, and are formed on the inorganic insulating film12. Specifically, each of the internal lead wire DW, the relay wire LW, and the terminal wire TW is a monolayer film or a multilayer film formed of at least one of the metals stated before.

The terminal wire TW of the first lead wire43ais connected to a through electrode44aformed through the inorganic insulating films13and14. Connected to this through electrode44ais a terminal45acting as an external connection terminal. The terminal45is connected, for example, to not-shown terminals of a flexible printed circuit (FPC)50and a semiconductor chip. Note that the terminal45has a top face covered with the planarization film15. The top face has a portion exposed to be connected to the FPC50.

Meanwhile, the first lead wire43bis led from the source electrode S and the drain electrode D in the internal wiring of the TFT layer10illustrated inFIG.2. Here, the source electrode S and the drain electrode D are formed after the inorganic insulating film13is formed. Hence, as illustrated inFIG.4, the first lead wire43bis also formed on the inorganic insulating film13.

As illustrated inFIG.4, the first lead wire43bincludes: the internal lead wire DW; the relay wire LW; and the terminal wire TW, as the first lead wire43aincludes.

The internal lead wire DW is formed to extend from the source electrode S and the drain electrode D. The relay wire LW and the terminal wire TW are formed in the same step as the source electrode S and the drain electrode D are formed. Hence, each of the internal lead wire DW, the relay wire LW, and the terminal wire TW is a metal monolayer film or a metal multilayer film made formed of the same materials as the gate electrode G and the drain electrode D are formed, and is provided on the inorganic insulating film13.

As illustrated inFIG.4, the terminal wire TW of the first lead wire43bis connected to a through electrode44bformed through the inorganic insulating film14. Connected to this through electrode44bis the terminal45. The terminal45is connected to not-shown terminals of the FPC50and a semiconductor chip.

Short Ring

In the manufacturing process of the active matrix substrate AMC1, a plurality of terminals45, including the terminal45, are externally exposed before such components as the FPC50are attached to the terminals45. Hence, static produced in the manufacturing process breaks a pixel drive element, and the broken drive element frequently causes faulty characteristics of the organic EL display device1.

Hence, in the process of manufacturing the active matrix substrate AMC1, a second lead wire61illustrated inFIGS.3and4is formed to externally extend from each terminal45. This second lead wire61is connected to a conductor or a semiconductor referred to as a short ring62, and short-circuited. Hence, the short ring62, a conductor or a semiconductor, is provided to have all the terminals45short-circuited, so that, when static is produced, the short ring62discharges the static. At the end of the manufacturing process, this short ring62is separated as the second lead wire61is separated along a separation line SL. Each second lead wire61is separated in a predetermined position with a laser beam or a diamond cutter. The separation line SL is a line through which the separated second lead wires61are imaginarily connected together in the separated positions.

A configuration of the second lead wire61is described, with reference toFIGS.3and4.

As illustrated inFIG.3, if the first lead wire43ais connected to the gate electrode G, a second lead wire61ais formed as the second lead wire61.

The second lead wire61aillustrated, inFIG.3includes: a first through electrode TE1aconnected to the terminal wire TW of the first lead wire43a; an internal lead line. SE1connected to another end of the first through electrode TE1a; a second through electrode TE2connected to another end of the internal lead line SE1; and a conductive semiconductor layer ECS connected to another end of the second through electrode TE2. The first through electrode TE1apenetrates the inorganic insulating films13and14. The second through electrode TE2penetrates the inorganic insulating films13and14, and a portion of the inorganic insulating film12.

The first through electrode TE1a, the internal lead line SE1, and the second through electrode TE2included in the second lead wire61aare made of a metal film. The conductive semiconductor layer ECS included in the second lead wire61ais made of a conductive semiconductor layer.

Meanwhile, a second lead wire61billustrated inFIG.4includes: a first through electrode TE1bconnected to the terminal wire TW of the first lead wire43b: the internal lead line SE1connected to another end of the first through electrode TE1b; the second through electrode TE2connected to another end of the internal lead line SE1; and the conductive semiconductor layer ECS connected to another end of the second through electrode TE2. The first through electrode TE1bpenetrates the inorganic insulating film14. The second through electrode TE2penetrates the inorganic insulating films13and14, and a portion of the inorganic insulating film12.

The first through electrode TE1a, the internal lead line SE1, and the second through electrode TE2included in the second lead wire61bare made of a metal film. The conductive semiconductor layer ECS included in the second lead wire61bis made of a conductive semiconductor layer.

As a result, the only difference between the second lead wire61aand the second lead wire61bis the one between the first through electrode TE1aand the second through electrode TE1b.

Next, formed outside the second lead wires61aand61bis the short ring62made of a conductor or a semiconductor.

The short ring62illustrated inFIGS.3and4includes: a third through electrode TE3connected to the second lead wire61aor the second lead wire61b; an external lead line SE2connected to the third through electrode TE3; a fourth through electrode TE4connected to another end of the external lead line SE2; a source region SA connected to the fourth through electrode TE4; a semiconductor layer SC connected to the source region SA; a drain region DA connected to the semiconductor layer SC; a fifth through electrode TE5connected to an end of the drain region DA; and a redundant lead line SE3connected to another end of the fifth through electrode TE5. A gate terminal is formed above the semiconductor layer SC through the inorganic insulating film12. Moreover, a lead branch line SE4is formed above the gate terminal through the inorganic insulating films12and14.

This short ring62, to which the second lead wire61aor the second lead wire61bis connected, is either a conductor or a semiconductor as described before. Hence, each of the second lead wire61aand the second lead wire61bis short-circuited with the short ring62.

At the end of the manufacturing process, the second lead wires61aand61bare separated with a not-shown laser beam or diamond cutter along the separation line SL through which predetermined separation positions are imaginarily connected together as illustrated inFIGS.3and4.

Hence, as illustrated inFIGS.3and4in this embodiment, a slit63is formed of the inorganic insulating films12,13, and14(i.e., a first inorganic insulating film) along the separation line SL across the second lead wires61aand61bin a plan view. The slit63exposes the second lead wires61aand61b. Moreover, along the separation line SL across the second lead wires61aand61bin a plan view, the planarization film15fills the slit63to cover the second lead wires61aand61b.

When the second lead wires61aand61bare separated with a laser beam along the separation line SL in a plan view, the planarization film15made of resin can be readily cut with a laser beam or a diamond cutter.

Here, pitches between the second lead wires arranged across the separation line are conventionally the same as those between the first lead wires. Recent display devices, however, provide images with high definition, and that is why the terminal spacing and the electrical-lead spacing are set narrowly. A short ring region can be physically separated on a glass substrate. On a flexible substrate made of such a material as polyimide, the short ring region is separated with, for example, a laser beam and a diamond cutter. In such a case, polyimide burns black to be carbon, becomes electrically conductive, and causes an electric leak between the terminals.

Hence, the active matrix substrate AMC1according to this embodiment has a configuration illustrated inFIG.1.FIG.1is a plan view illustrating a main configuration of the active matrix substrate AMC1according to this embodiment.

That is, in the active matrix substrate AMC1of this embodiment illustrated inFIG.1, the second lead wires61are arranged with an arrangement pitch P1along the separation line SL. The arrangement pitch P1is greater than an arrangement pitch P2of the first lead wires43.

As a result, the active matrix substrate AMC1can prevent an electric leak between the terminals45.

Hence, the active matrix substrate AMC1according to this embodiment includes the terminals45as external connection terminals arranged near the display region41. The active matrix substrate AMC1includes: the first lead wires43each extending from one of the terminals45to the display region41; and the second lead wires61each extending from one of the terminals45to the separation line SL. The second lead wires61are arranged with the arrangement pitch P1along the separation line SL. The arrangement pitch P1is greater than the arrangement pitch P2of the first lead wires43extending from the terminals45. Note that, if the arrangement pitch P2of the first lead wires43includes a plurality of arrangement pitches P2, and the arrangement pitch P1, of the second lead wires61, along the separation line SL includes a plurality of arrangement pitches P1, the smallest pitches of the respective arrangement pitches P2and P1are compared.

For example, if the active matrix substrate AMC1includes a resin substrate, the resin is carbonized to be electrically conductive as the resin substrate is separated, and remained as carbon. The carbonized resin could cause an electric leak between the terminals45.

In this embodiment, however, the arrangement pitch P1, of the second lead wires61, along the separation line SL is greater than the arrangement pitch P2of the first lead wires43extending from the terminals45. Hence, even if the resin of the resin substrate is carbonized when the resin substrate is separated with, for example, a laser beam, the carbonized resin is less likely to remain across the first lead wires43.

As a result, the active matrix substrate AMC1can prevent an electric leak between the terminals45.

Moreover, the active matrix substrate AMC1, according to this embodiment, includes the inorganic insulating films12to14and the planarization film15stacked on top of another in the stated order on the second lead wires61aand62b. The inorganic insulating films12to14act as a first inorganic insulating film, and the planarization film15is made of resin. The active matrix substrate AMC1includes the slit63formed of the inorganic insulating films12to14along the separation line SL across the second lead wires61aand61bin a plan view. The slit63exposes the second lead wires61aand61b. Along the separation line SL across the lead wires61aand61bin a plan view, the planarization film15fills the slit63to cover the second lead wires61aand61b.

When the second lead wires61aand61bare separated with a laser beam along the separation line SL in a plan view, only the planarization film15made of resin is found above the second lead wires61aand61b. As a result, the second lead wires61aand61bare readily cut with a laser beam along the separation line SL.

The active matrix substrate AMC1according to this embodiment includes the barrier layer3as a second inorganic insulating film formed below, and in contact with, the second lead wires61aand61b. The resin substrate2is formed below the barrier layer3.

Such a configuration is the same as that of the display region41included in the active matrix substrate AMC1. As a result, the second lead wires61aand61bcan be readily formed in a step of forming the display region41of the active matrix substrate AMC1.

Such a feature makes it possible to form the second lead wires61aand61bwithout newly adding a different step, contributing to readily forming the second lead wires61aand61b.

In the active matrix substrate AMC1according to this embodiment, the second lead wires61aand61bacross the separation line SL are conductive, and formed of the same material as the semiconductor layer is formed. Such a feature allows the second lead wires61aand61bto readily function as a conductive material.

In the active matrix substrate AMC1according to this embodiment, the second lead wires61aand61binclude an internal lead line SE1made of a metal film formed of the same material, and in the same layer, as a metal wire in the display region41is formed. As a result, in a step of forming the display region41of the active matrix substrate AMC1, the internal lead line SE1is formed in the same steps of (i) forming the gate electrode as a metal wire and (ii) forming the source electrode as a metal wire connected to the source region and the drain electrode as a metal wire connected to the drain region. Such a feature makes it possible to readily form the second lead wires61aand61bincluding the internal lead line SE1made of a metal film.

The organic EL display device1as a display device according to this embodiment includes the active matrix substrate AMC1. The separation line SL coincides with a display panel end face40a(seeFIG.8to be shown later) included in the organic EL display device1. Such a feature allows the organic EL display device1to include the active matrix substrate AMC1capable of preventing an electric leak between the terminals45.

Second Embodiment

Described below is another embodiment of the disclosure, with reference toFIGS.5to7. This embodiment and the first embodiment share the same configurations except a configuration described in this embodiment. Like reference signs designate identical or corresponding components throughout the drawings between this embodiment and the first embodiment, and therefore will not be elaborated upon here.

The difference between an active matrix substrate AMC2of this embodiment and the active matrix substrate AMC1of the first embodiment is that the former includes the configuration of the latter, and further includes a short ring70provided with a ring transistor.

Described below is a configuration of the active matrix substrate AMC2according to this embodiment, with reference toFIGS.5to7.FIG.5is a plan view illustrating a configuration of a first short ring71aand a second short ring71bof the active matrix substrate AMC2according to this embodiment.FIG.6is a plan view illustrating a configuration of a first short ring72aand a second short ring72bof the active matrix substrate AMC2according to this embodiment.FIG.7is a plan view illustrating a configuration of a first short ring73aand a second short ring73bof the active matrix substrate AMC2according to this embodiment.

As illustrated inFIG.1, for example, suppose the short ring62is a single conductor or a single semiconductor, or is made only of a conductor partially including a semiconductor. If one of the terminals45produces static and the static flows into the second lead wire61a, the static might backflow into the second lead wire61bthrough the short ring62.

Hence, in the active matrix substrate AMC2of this embodiment as illustrated inFIG.5, the short ring70is dual-redundant and includes the first short ring71aand the second short ring71b.

The active matrix substrate AMC2includes ring transistors TR1and TR2provided to the second lead wires61aand61band formed between the separation line SL and the first short ring71a. Each of the ring transistors TR1and TR2has a gate terminal G and a source terminal S electrically connected together.

The gate terminal G and the source terminal S of each of the ring transistors TR1and TR2are electrically connected together. Hence, the ring transistors TR1and TR2act as diode transistors, and keep a current from flowing from a drain terminal D toward the source terminal S.

As a result, even if static flows into the first short ring71aand the second short ring71bof one of the second lead wires61aand61b, the flowing static does not backflow into another one of the second lead wires61aand61b.

In particular, as illustrated inFIG.5of this embodiment, the first ring transistor TR1is formed between the second lead wire61aand the first short ring71a. Furthermore, the second ring transistor TR2is formed to have a source terminal S and a gate terminal G electrically connected to the second lead wire61b, and a drain terminal D electrically connected to the second lead wire61a.

Hence, in the first short ring71a, the current flows only toward the left inFIG.5. In the second short ring71b, the current flows only toward the right inFIG.5.

As a result, the dual-redundant first short ring71aand second short ring71bdisperse the static therebetween, and conduct the static in the opposite directions. Such a feature makes it possible to efficiently disperse and reduce the static.

Note thatFIG.5illustrates an example of the first ring transistor TR1and the second ring transistor TR2when the second lead wires61aand61b, the first short ring71a, and the second short ring71bare each formed of a metal film.

Alternatively, the second lead wires61aand61b, a first short ring72a, and a second short ring72beach can be made of a semiconductor. In such a case, the first ring transistor TR1and the second ring transistor TR2can be configured as illustrated inFIG.6.

Furthermore, if the second lead wires61aand61b, a first short ring73a, and a second short ring73bare each formed of a metal film, the first ring transistor TR1and the second ring transistor TR2can be configured as illustrated inFIG.7. Note thatFIG.7illustrates an example in which the terminals45are staggered.

As can be seen, the active matrix substrate AMC2of this embodiment includes ring transistors; namely, the first ring transistor TR1and the second ring transistor TR2are provided to the second lead wires61aand61band are formed between the separation line SL and the first and second short rings73aand73b. Each of the first ring transistor TR1and the second ring transistor TR2has a gate terminal G and a source terminal S electrically connected together.

Thus, even if the static flows from the terminals45through the second lead wires61aand61b, the current of the static does not flow toward the terminals45from the first ring transistor TR1and the second ring transistor TR2. That is, the static does not backflow. Hence, even if the current of the static flows through the second lead wire61ainto the first short ring73aand the second short ring73b, the current does not backflow through the second lead wire61btoward the terminals45.

Hence, the static produced closer to the terminals45disperses only in one direction toward the first short ring73aand the second short ring73b, and does not backflow.

Moreover, in the active matrix substrate AMC2according to this embodiment, the short ring70is dual-redundant and includes the first short ring73aand the second short ring73b. The first ring transistor TR1is formed between the neighboring second lead wires61aand61b, and having a source terminal S and a gate terminal G electrically connected to the second lead wire61aand a drain terminal D electrically connected to the second lead wire61b. The second ring transistor TR2has a source terminal S and a gate terminal G electrically connected to the second lead wire61b, and a drain terminal D electrically connected to the second lead wire61a.

Thanks to such features, currents of the static flowing through the second lead wire61ainto the first short ring73aand into the second short ring73bflow in opposite directions. The currents flowing into the first short ring73aand the second short ring73bact on, and cancel out, each other. As a result, the static flowing into the first short ring73aand the second short ring73bcan be efficiently reduced.

The source terminal S and the gate terminal G of the first ring transistor TR1are respectively connected to the gate terminal G and the source terminal S of the second ring transistor TR2. Hence, when a current of large static flows to the source terminal S, the charges of the current also flow to the gate terminal G. As a result, the current is likely to flow from the source terminal S to the drain terminal D.

Hence, in this embodiment, the first ring transistor TR1and the second ring transistor TR2are more likely to conduct the current of the static as the static is larger. Such a feature allows the current to flow efficiently through the short ring70, and, as a result, the static disperses efficiently.

Third Embodiment

Described below is still another embodiment of the disclosure, with reference toFIGS.8to10. This embodiment and the first embodiment share the same configurations except a configuration described in this embodiment. Like reference signs designate identical or corresponding components throughout the drawings between this embodiment and the first embodiment, and therefore will not be elaborated upon here.

A mother substrate of this embodiment includes a plurality of the active matrix substrates AMC1and the AMC2.

Configurations of mother substrates60and60′ are described below, with reference toFIGS.8and9.FIG.8is a plan view illustrating a configuration of the mother substrate60including the active matrix substrates AMC1.FIG.9is a plan view illustrating a configuration of a modification of the mother substrate60; that is, the mother substrate60′ including the active matrix substrates AMC2. Note thatFIGS.8and9omit some of the first lead wires43.

In manufacturing the active matrix substrates AMC1and AMC2, preferably used are the mother substrate60and the mother substrate60′ respectively including a plurality of the active matrix substrates AMC1and a plurality of the active matrix substrates AMC2. Thanks to such a feature, the active matrix substrates AMC1and AMC are simultaneously manufactured in the same steps, improving efficiency in the manufacturing. Note that, inFIG.8, the separation line SL coincides with the display panel end face40aof the organic EL display device1. That is, the separation line SL is the display panel end face40a. Hence, the mother substrate60is divided by the separation line SL into individual display panels40.

In such a case, for example, the short ring62is also preferably shared between the display panels40. Hence, as illustrated inFIG.8, for example, the mother substrate60of this embodiment includes a plurality of the active matrix substrates AMC1planarly arranged. The mother substrate60inFIG.8includes at least one active matrix substrate pair in which the terminals45of a first active matrix substrate AMC1_1and the terminals45of a second active matrix substrate AMC1_2are planarly arranged to face each other. The mother substrate60includes, for example, three such active matrix substrate pairs.

Such a feature makes it possible to manufacture at least one active matrix substrate pair from one mother substrate60.

Moreover, in the mother substrate60according to this embodiment, one short ring62is provided in common with the terminals45of the first active matrix substrate AMC1_1and the terminals45of the second active matrix substrate AMC1_2.

Hence, the static produced closer to the terminals45disperses only in one direction toward the short ring62, and does not backflow. Moreover, one short ring62is provided in common with the first active matrix substrate AMC1_1and the second active matrix substrate AMC1_2, making it possible to reduce the number of short rings62.

Here, as illustrated inFIG.9, a modification of this embodiment; namely, the mother substrate60′, includes the short ring70shaped into frames each provided around one of the active matrix substrates AMC2.

Hence, the short ring70runs in a long distance. As a result, when the static disperses from one of the second lead wires61to the short ring70, the static travels through the long distance. Such a feature makes it possible to reduce a current of the static coming back to the terminals through another second lead wire61.

In other words, the mother substrate60′ of this embodiment includes a plurality of the active matrix substrates AMC2. Each of the active matrix substrates AMC2includes a short ring so that the second lead wires61of the matrix substrate AMC2extend across the separation line SL from the terminals45and connect to the short ring70.

The active matrix substrate AMC2of this embodiment includes the short ring70shaped into a frame. Described here is the short ring70on a side, of the active matrix substrate AMC2, not facing the terminals45.FIG.10is a plan view illustrating a configuration of the short ring70on a side, of the active matrix substrate AMC2, not facing the terminals45. Note thatFIG.10shows as an example of a conductor or a semiconductor to be extended when the active matrix substrate AMC2includes the first short ring71aand the second short ring71binFIG.5of the second embodiment.

FIG.10illustrates the side not facing the terminals45that act as external connection terminals of the active matrix substrate AMC2. The side is provided with a first connection wire71a′ and a second connection wire71b′ running in parallel with the side. The first connection wire71a′ and the second connection wire71b′ respectively extend from the first short ring71aand the second short ring71billustrated inFIG.5. Each of the first connection wire71a′ and the second connection wire71b′ partially includes an intrinsic semiconductor layer TSC. The intrinsic semiconductor layer TSC of the first connection wire71a′ includes: a first ring side transistor TR1acting as a diode transistor and having a source terminal S and a gate terminal G of the first connection wire71a′ electrically connected together; and the intrinsic semiconductor layer TSC of the second connection wire71b′ includes a second ring transistor TR2acting as a diode transistor and including a source terminal S and a gate terminal G of the second connection wire71b′ electrically connected together. Note that the side, of the active matrix substrate AMC2, not facing the terminals45includes three sides other than a side, of the active matrix substrate AMC2, having the terminals45. Moreover, the intrinsic semiconductor layers TSC are not conductive.

Hence, the first short ring71a, the first connection wire71a′, the second short ring71b, and the second connection wire71b′ formed all around the AMC2disperse currents of static in opposite directions. Such a feature makes it possible to disperse the static more efficiently.

Note that, in the above example, only the first short ring71aand the second short ring71billustrated inFIG.5correspond to the first connection wire71a′ and the second connection wire71b′. However, the corresponding relationship in an aspect of the disclosure may include any given one. For example, the corresponding relationship may also be applicable to the first short ring72aand the second short ring72billustrated inFIG.6, and to the first short ring73aand the second short ring73binFIG.7.

Fourth Embodiment

Described below is still another embodiment of the disclosure, with reference toFIG.11. This embodiment and the first to third embodiments share the same configurations except a configuration described in this embodiment. Like reference signs designate identical or corresponding components throughout the drawings between this embodiment and the first to third embodiments, and therefore will not be elaborated upon here.

The active matrix substrate AMC2of this embodiment is different in that a terminal transistor is provided between the terminals45and the separation line SL.

Described below is a configuration of the active matrix substrate AMC2according to this embodiment, with reference toFIG.11.FIG.11is a plan view illustrating a configuration of an end of the active matrix substrate AMC2according to this embodiment.

The active matrix substrate AMC2of this embodiment is the one illustrated inFIG.7, and further includes a terminal transistor81between the terminals45and the separation line SL.

For example, when the short ring70is separated by the separation line SL across the second lead wires61aand61b, static might enter from an exposed portion of the second lead wires61aand61b. In this embodiment, the second lead wires61aand61bare partially formed of the semiconductor layer SC. Hence, the semiconductor layer SC, a part of the second lead wires61aand61b, is provided with: a terminal45as a source terminal S; a drain terminal D toward the separation line SL; and a gate terminal G above the semiconductor layer SC. Such a configuration forms a transistor. Moreover, in this embodiment, the terminal transistor81has the source terminal S and the gate terminal G electrically connected together. Hence, a current does not flow from the drain terminal D to the source terminal S.

As a result, even if static enters from the portion of the second lead wires61aand61bexposed on the separation line SL, the current of the static does not flow toward the terminals45from the terminal transistor81.

Such a feature makes it possible to keep the static from coming toward the terminals45after the separation of the second lead wires61aand61b.

Note that, in the above example, the active matrix substrate AMC2illustrated inFIG.7is provided with the terminal transistor81. However, in an aspect of the disclosure, the active matrix substrate AMC2shall not be limited to the one illustrated inFIG.7. Alternatively, for example, the active matrix substrate AMC2illustrated inFIGS.5and6may also be provided with the terminal transistor81.

Fifth Embodiment

Described below is still another embodiment of the disclosure, with reference toFIG.12. This embodiment and the first to fourth embodiments share the same configurations except a configuration described in this embodiment. Like reference signs designate identical or corresponding components throughout the drawings between this embodiment and the first to fourth embodiments, and therefore will not be elaborated upon here.

The active matrix substrate AMC2of this embodiment is different in that a terminal transistor is provided between the terminals45and the separation line SL.

Described below is a configuration of the active matrix substrate AMC2according to this embodiment, with reference toFIG.12.FIG.12is a plan view illustrating a configuration of an end of the active matrix substrate AMC2according to this embodiment.

The active matrix substrate AMC2of this embodiment is the one illustrated inFIG.7, and further includes a third ring transistor82between the separation line SL and the short ring70.

In this embodiment, the second lead wires61aand61bare partially formed of the semiconductor layer SC. Hence, the semiconductor layer SC, a part of the second lead wires61aand61b, is provided with: a terminal45as a source terminal S; a drain terminal D toward the separation line SL; and a gate terminal G above the semiconductor layer SC. Such a configuration forms a transistor. Moreover, in this embodiment, the third ring transistor82has the source terminal S and the gate terminal G electrically connected together. Hence, a current does not flow from the drain terminal D to the source terminal S.

When static flows from one of the of the terminals45through a second lead wire61ato the short ring70, such a feature can prevent backflow of the static from the short ring70through a second lead wire61btoward the terminals45.

If the third ring transistor82is not provided, a route from one of the terminals45to the second lead wire61a, to the short ring70, to the second lead wire61b, and to another terminal45should preferably be long in view of the prevention of the backflow of the static. However, the route should preferably be short in view of a space for installing the second lead wire61a.

Hence, the active matrix substrate AMC2of this embodiment is provided with the third ring transistor82, making it possible to reliably prevent the backflow of the static. As a result, the second lead wires61aand61bcan be shortened between the terminals45and the separation line SL. Such a feature makes it possible to reduce a space for the second lead wires61aand61bbetween the terminals45and the separation lines SL, contributing to downsizing of the display panel40.

Note that, in the above example, the active matrix substrate AMC2illustrated inFIG.7is provided with third ring transistor82. However, in an aspect of the disclosure, the active matrix substrate AMC2shall not be limited to the one illustrated inFIG.7. Alternatively, for example, the active matrix substrate AMC2illustrated inFIGS.5and6may also be provided with the third ring transistor82.

SUMMARY

An active matrix substrate according to a first aspect of the disclosure includes a resin substrate including a plurality of external connection terminals arranged near a display region. The active matrix substrate includes: a plurality of first lead wires each extending from one of the external connection terminals to the display region; and a plurality of second lead wires each extending from one of the external connection terminals to a separation line. The second lead wires are arranged with an arrangement pitch along the separation line, and the arrangement pitch of the second lead wires is greater than an arrangement pitch of the first lead wires. Note that each second lead wire is separated in a predetermined position. The separation line is a line through which the separated lead wires are imaginarily connected together in the separated positions. Moreover, if the arrangement pitch of the first lead wires includes a plurality of arrangement pitches, and the arrangement pitch, of the second lead wires, along the separation line includes a plurality of arrangement pitches, the smallest pitches of the respective arrangement pitches are compared.

The active matrix substrate according to a second aspect of the disclosure may further include: a first inorganic insulating film and a planarization film stacked on top of another in a stated order on the second lead wires, the planarization film being made of resin; and a slit formed of the first inorganic insulating film along the separation line across the second lead wires in a plan view, the slit exposing the second lead wires. Along the separation line across the second lead wires in a plan view, the planarization film may fill the slit to cover the second lead wires.

The active matrix substrate according to a third aspect of the disclosure may further include a second inorganic insulating film formed below, and in contact with, the second lead wire. The resin substrate may be formed below the second inorganic insulating film.

In the active matrix substrate according to a fourth aspect of the disclosure, the second lead wires across the separation line may be conductive, and formed of the same material as a semiconductor layer is formed.

In the active matrix substrate according to a fifth aspect of the disclosure, the second lead wires may include a portion made of a metal film formed of the same material, and in the same layer, as a metal wire in the display region is formed.

The active matrix substrate according to a sixth aspect of the disclosure may further include a terminal transistor formed on the second lead wires and provided between the external connection terminals and the separation line. The terminal transistor may have a gate terminal and a source terminal electrically connected together.

A display apparatus according to a seventh aspect of the disclosure includes the active matrix substrate. The separation line coincides with an end face of a display panel included in the display device.

A mother substrate according to an eighth aspect of the disclosure includes a plurality of active matrix substrates planarly arranged and including the active matrix substrate.

In the mother substrate according to a ninth aspect of the disclosure, each of the active matrix substrates may include a short ring, so that the second lead wires of the active matrix substrate may extend across the separation line from the terminals and connect to the short ring. Note that the short ring, a conductor or a semiconductor, is provided to have all the terminals short-circuited, so that, when static is produced, the short ring discharges the static.

In the mother substrate according a tenth aspect of the disclosure, the short ring may be provided in common with neighboring active matrix substrates included in the active matrix substrates.

In the mother substrate according to an eleventh aspect of the disclosure, the short ring may be shaped into frames each provided around one of the active matrix substrates.

The mother substrate according to a twelfth aspect of the disclosure may further include a ring transistor provided to the second lead wires and formed between the separation line and the short ring. The ring transistor may have a gate terminal and a source terminal electrically connected together.

In the mother substrate according to a thirteen aspect of the disclosure, the short ring may be dual-redundant and includes a first short ring and a second short ring, and the ring transistor may include: a first ring transistor formed between neighboring second lead wires included in the second lead wires, and having a source terminal and a gate terminal electrically connected to one of the neighboring second lead wires and having a drain terminal electrically connected to another one of the neighboring second lead wires; and a second ring transistor having a source terminal and a gate terminal electrically connected to the other one of the neighboring, second lead wires, and a drain terminal electrically connected to the one of the neighboring second lead wires.

In the mother substrate according to a fourteenth aspect of the disclosure, each of the active matrix substrates may have a side not facing the external connection terminals. The side may be provided with a first connection wire, and a second connection wire may run in parallel with the side and respectively extend from the first short ring and second short ring. Each of the first connection wire and the second connection wire may partially include an intrinsic semiconductor layer including a diode transistor having a source terminal and a gate terminal, of the first connection wire and the second connection wire, electrically connected together. Note that the side, of the active matrix substrate, not facing the terminals includes three sides other than a side, of the active matrix substrate, having the terminals.

Note that an aspect of the disclosure shall not be limited to the embodiments described above, and can be modified in various manners within the scope of claims. The technical aspects disclosed in different embodiments are to be appropriately combined together to implement another embodiment. Such an embodiment shall be included within the technical scope of the aspect of the disclosure. Moreover, the technical aspects disclosed in each embodiment may be combined to achieve a new technical feature.