CN101414620B - Electronic device, thin-film transistor structure, and flat panel display having the same - Google Patents

Abstract

The present invention relates to electronic devices, thin film transistor structures and flat panel displays having the structures. The invention provides an electronic device for avoiding or reducing electrostatic discharge causing pixel failure. An electronic device manufactured according to the principles of the present invention may comprise a plurality of conductive layers intersecting but not in contact with each other, as well as tabs, wherein at least one of the conductive layers includes a width varying portion, the width of which varies along at least one of the conductive layers The lengthwise variation of the tabs is connected to at least one conductive layer in regions that do not intersect adjacent conductive layers. Alternatively, the width of the width varying portion may vary continuously along the length direction of the at least one conductive layer, and may also have blunt corner edges. The present invention also provides a flat-panel organic electroluminescent display (OELD) or LCD display device comprising such an electronic device.

Description

Electronic device, thin film transistor structure and flat panel display having the same

This application is a divisional application for an invention patent application with an application date of June 30, 2005, an application number of 200510080518.1, and an invention title of "Electronic Device, Thin Film Transistor Structure, and Flat Panel Display with the Structure". the

Cross-references to related applications

This application claims priority to Korean Patent Applications 10-2004-0050445 and 10-2004-0050446 filed with the Korean Intellectual Property Office on June 30, 2004, the disclosures of which are incorporated herein by reference in their entirety. the

technical field

The present invention generally relates to electronic devices such as thin film transistors (TFTs) and flat panel display devices having the same. However, the present invention particularly relates to an electronic device in which electrostatic breakdown caused by static electricity is avoided or reduced and a flat panel display device having the same. the

Background technique

There are a variety of display devices that can be used to display images. Recently, a variety of flat panel display devices have replaced cathode ray tube (CRT) displays. Flat panel display devices can be classified into emissive type and non-emissive type according to the type of light emission used. Emissive display devices include flat CRT display devices, plasma display panel devices, vacuum fluorescent display devices, field emission display devices, and organic/inorganic electroluminescence display devices, while non-emissive display devices include liquid crystal display devices. A planar emission type organic electroluminescence display device (OELD) has attracted attention since it is an emission type, does not include a light emitting device such as a backlight, and can operate at low power consumption and high efficiency. OELD devices have the advantages of low operating voltage, light weight, thin profile, wide viewing angle and fast video response time. the

A conventional electroluminescence unit of an OELD device includes a first electrode (anode), a second electrode (cathode) formed in a stacked type on a substrate, and an organic light emitting layer (thin film) interposed between the first electrode and the second electrode. In operation, the OELD device emits light with a specific wavelength through energy generated by excitons, which are formed by the recombination of electrons and holes injected through the anode and cathode in the organic thin film. An electron transport layer (ETL) may be disposed between the cathode and the organic light emitting layer. Similarly, a hole transport layer (HTL) may be disposed between the anode and the organic light emitting layer. Also, a hole injection layer (HIL) may be provided between the anode and the HTL. In addition, an electron injection layer (EIL) may be disposed between the cathode and the ETL. the

A passive matrix (PM) OELD device can use a manual driving method, while an active matrix (AM) type can use an active driving method. In PM OELD devices, the anodes are arranged in columns and the cathodes are arranged in rows. The row driving circuit provides scanning signals to the cathode, and the column driving circuit provides data signals to each pixel. AM OLED devices, on the other hand, use thin-film transistors (TFTs) to control signals input to pixels. Because the use of TFT enables AMOELD to process a large number of signals quickly, AMOELD is widely used to perform excitation. the

A disadvantage of conventional AM OELD devices is that one or more erroneous pixels may be generated in the display area due to the generation and/or discharge of static electricity during manufacture or use of the device. the

FIG. 1A is a planar photogram of a conventional OELD device showing erroneous pixels as bright spots. FIG. 1B is an enlarged view of a normal pixel marked as A in FIG. 1A , and FIG. 1C is an enlarged view of an error pixel marked as B in FIG. 1A . 1B and 1C are bottom views of the conventional OELD device of FIG. 1A. The bottom view is obtained through the multilayer structure of the substrate and the various electronic and electroluminescent components mounted on it. Therefore, in FIGS. 1B and 1C , the gate lines 3 a and 3 b appear above the conductive layer 5 . the

In FIG. 1B and FIG. 1C, each pixel 1a and 1b includes an electroluminescence unit, a gate electrode (2a of FIG. 1B and 2b of FIG. 1C) and a light-emitting thin film transistor (Ma of FIG. 1B and Mb of FIG. 1C), The light emitting thin film transistor transmits an electrical signal from a driving TFT (not shown) to the pixel. The source electrodes of the light emitting TFTs Ma and Mb are electrically connected to a driving TFT (not shown) via a conductive layer 5 . the

Figure 1D is an enlarged plan view of a portion denoted B' in Figure 1C. Referring to Figure ID, the conductive layer 5 may extend through other conductive layers. For example, in the enlarged bottom view of FIG. 1D, the conductive layer 5 is shown passing through the gate lines 3a/3b. In the illustrated figure, the gate lines 3 a / 3 b appear above the conductive layer 5 . In operation, the gate lines 3a/3b function as scan lines and/or scan line extension units for providing electrical signals to the thin film transistors. the

To meet design specifications, the width of each gate line 3a/3b may vary along its length. For example, in the conventional designs shown in FIG. 1B , FIG. 1C and FIG. 1D , the width of each gate line 3 a / 3 b changes at the portion where it intersects with the conductive layer 5 . As shown in FIG. 1D , the wider portion of the gate line 3b may be the width changing portion A _w , and the narrower connecting portion of the gate line 3a/3b may be the cross unit _Ac . The width changing portion _Aw and the intersecting unit _Ac may be insulated from the conductive layer 5 and located within respective boundaries. Electrostatic discharge (ESD) tends to occur at the corner portion _Ad of the width changing portion _Aw shown in FIG. 1D because current tends to discharge at the tip of the conductor. In most cases, ESD damages the corresponding pixel 1a/1b, causing it to emit excessive light (eg, a bright spot such as bright spot B shown in FIG. 1A appears). Such ESD is easily induced since static electricity is concentrated at the crossing portion, so if the insulating layer interposed between the conductive layers is damaged, the possibility of a short circuit between the crossing conductive layers increases. As described in FIG. 1B and FIG. 1C, even if the same current signal is input to the pixel 1a in FIG. 1B and the pixel 1b in FIG. 1C, the pixel 1b in FIG. Highlights of great brightness. A greater brightness occurs because the short-circuit currents between the different conductive layers 3b and 5 cause and use more than one desired different current signal. This unwanted ESD may degrade the image quality of planar OELDs, which require high uniformity across the entire display area.

Contents of the invention

The present invention provides an electronic device and a TFT structure, wherein the generation of wrong pixels caused by electrostatic damage of the conductive layer is reduced or avoided, and a planar emission type organic electroluminescent display (OELD) device having the structure is provided . the

One aspect of the present invention provides an electronic device, comprising: a first conductive layer; and a second conductive layer crossing the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the The first conductive layer includes a width variation portion in a region where the first conductive layer intersects the second conductive layer, and the width of the width variation portion varies along the length direction of the first conductive layer, wherein the The width of the second conductive layer is constant in the region where the first conductive layer intersects with the second conductive layer, and wherein the sum of the line segment connecting two points on the same plane as the outer line of the width changing portion and the The included angle between the parallel line segments in the longitudinal direction of the first conductive layer is less than 90°. the

One aspect of the present invention provides a TFT structure, comprising: a first conductive layer; and a second conductive layer crossing the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the The first conductive layer includes a width variation portion in a region where the first conductive layer intersects the second conductive layer, and the width of the width variation portion varies along the length direction of the first conductive layer, wherein the The width of the second conductive layer is constant in the region where the first conductive layer intersects with the second conductive layer, and wherein the line segment connecting two points on the same plane as the outer line of the width changing portion and the The included angle between the parallel line segments in the length direction of the first conductive layer is less than 90°. the

One aspect of the present invention provides a flat panel display device, comprising: a substrate; a TFT layer formed on the substrate; and a pixel layer including more than one pixel electrically connected to the TFT layer, wherein the TFT layer includes a first conductive layer and the A second conductive layer crossed by a first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the first conductive layer is intersected by the first conductive layer and the second conductive layer The area includes a width changing portion, the width of the width changing portion changes along the length direction of the first conductive layer, wherein the width of the second conductive layer is crossed by the first conductive layer and the second conductive layer is constant in the area of , and the angle between the line segment connecting two points located on the same plane as the outer line of the width changing portion and the line segment parallel to the length direction of the first conductive layer is less than 90°. the

One aspect of the present invention provides an electronic device, comprising: a first conductive layer; and a second conductive layer crossing the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the The first conductive layer includes a part whose cross-sectional area changes along the length direction of the first conductive layer, and the part is in the crossing area of the first conductive layer and the second conductive layer, wherein the second conductive layer The width of the layer is constant in the region where the first conductive layer intersects with the second conductive layer, and wherein a line segment connecting two points on the same plane as an outer line of a portion where the cross-sectional area changes and the second The included angle between the parallel line segments in the longitudinal direction of a conductive layer is less than 90°. the

One aspect of the present invention provides a TFT structure, comprising: a first conductive layer; and a second conductive layer crossing the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the The first conductive layer includes a part whose cross-sectional area changes along the length direction of the first conductive layer, and the part is in the crossing area of the first conductive layer and the second conductive layer, wherein the second conductive layer The width of the layer is constant in the region where the first conductive layer intersects with the second conductive layer, and wherein a line segment connecting two points on the same plane as an outer line of a portion where the cross-sectional area changes and the second The included angle between the parallel line segments in the longitudinal direction of a conductive layer is less than 90°. the

One aspect of the present invention provides a flat panel display device, comprising: a substrate; a TFT layer formed on the substrate; and a pixel layer including more than one pixel electrically connected to the TFT layer, wherein the TFT layer includes a first conductive layer and is connected to the TFT layer. A second conductive layer intersecting the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the first conductive layer includes a cross-sectional area that varies along the length direction of the first conductive layer part, which is in the region where the first conductive layer intersects the second conductive layer, wherein the width of the second conductive layer is in the region where the first conductive layer intersects the second conductive layer where is a constant, and wherein the angle between the line segment connecting two points located on the same plane as the outer line of the section with varying cross-sectional area and the line segment parallel to the length direction of the first conductive layer is less than 90°. the

One aspect of the present invention provides an electronic device comprising a plurality of conductive layers crossing but not in contact with each other. Wherein at least one conductive layer includes a width changing portion, and the width of the width changing portion changes along the length direction of the at least one conductive layer. The electronic device further includes a tab connected to at least one of the conductive layers or an adjacent conductive layer in a region remote from the overlapping region of the conductive layers. the

Another aspect of the present invention provides a TFT structure including a plurality of conductive layers crossing but not in contact with each other. Wherein at least one conductive layer includes a width changing portion, and the width of the width changing portion changes along the length direction of the at least one conductive layer. The TFT structure further includes a tab connected to at least one of the conductive layers or an adjacent conductive layer in a region away from the overlapping region of the conductive layers. the

Another aspect of the present invention provides a flat panel display device including a substrate, a TFT layer formed on the substrate, at least one insulating layer formed on the TFT layer, and a pixel layer, the pixel layer includes electrical connections through a through hole formed in the insulating layer. More than one pixel connected to the TFT layer. The TFT layer includes a plurality of conductive layers crossing but not in contact with each other. The at least one conductive layer includes a width varying portion, the width of which varies along the length of the at least one conductive layer. The flat panel display device further includes a tab connected to at least one conductive layer or an adjacent conductive layer at a region away from the overlapping region of the conductive layers. the

Another aspect of the present invention provides an electronic device comprising a plurality of conductive layers intersecting but not in contact with each other. The at least one conductive layer includes a width varying portion, the width of which varies along the length of the at least one conductive layer. The electronic device further includes an angle less than 90° between two line segments, one line segment connecting two points on the same plane as the outer line of the width changing portion, and the other line segment being parallel to the lengthwise direction of the at least one conductive layer. the

Another aspect of the present invention provides a TFT structure including a plurality of conductive layers crossing but not in contact with each other. The at least one conductive layer includes a width varying portion, the width of which varies along the length of the at least one conductive layer. The TFT structure further includes an included angle less than 90° between two line segments, one line segment connecting two points on the same plane as the outer line of the width changing portion, and the other line segment being parallel to the lengthwise direction of at least one conductive layer. the

Another aspect of the present invention provides a flat display device, comprising a substrate, a TFT layer formed on the substrate, at least one insulating layer formed on the TFT layer, and a pixel layer, the pixel layer comprising The vias are electrically connected to more than one pixel of the TFT layer. The TFT layer includes a plurality of conductive layers crossing but not in contact with each other. The at least one conductive layer includes a width varying portion, the width of which varies along the length of the at least one conductive layer. The TFT layer may further include an included angle less than 90° between two line segments, one line segment connecting two points on the same plane as the outer line of the width changing portion, and the other line segment being parallel to the lengthwise direction of at least one conductive layer. the

Another aspect of the present invention provides an electronic device comprising a plurality of conductive layers intersecting but not in contact with each other, wherein at least one conductive layer includes a portion whose cross-sectional area varies along the length direction of the at least one conductive layer. The electronic device may further comprise a tab connected to at least one conductive layer or an adjacent conductive layer at a region away from the overlapping region of the conductive layers. the

Another aspect of the present invention provides a TFT structure, including a plurality of conductive layers intersecting but not in contact with each other, wherein at least one conductive layer includes a portion whose cross-sectional area varies along the length direction of the at least one conductive layer. The TFT structure may further include a tab connected to at least one conductive layer or an adjacent conductive layer at a region away from the conductive layer overlapping region. the

Another aspect of the present invention provides a flat panel display device, comprising a substrate, a TFT layer formed on the substrate, at least one insulating layer formed on the TFT layer, and a pixel layer, the pixel layer comprising The vias are electrically connected to more than one pixel of the TFT layer. The TFT layer includes a plurality of conductive layers crossing but not in contact with each other. The at least one conductive layer includes portions that vary in cross-sectional area along the length of the at least one conductive layer. The flat panel display device may further include a tab connected to at least one conductive layer or an adjacent conductive layer at a region away from the overlapping region of the conductive layers. the

Another aspect of the present invention provides an electronic device comprising a plurality of conductive layers intersecting but not in contact with each other, wherein at least one conductive layer includes a portion whose cross-sectional area varies along the length direction of the at least one conductive layer. An angle between a line segment connecting two points on the same plane as the outer line of the width changing portion and a line segment parallel to the length direction of the at least one conductive layer is less than 90°. the

Another aspect of the present invention provides a TFT structure, including a plurality of conductive layers intersecting but not in contact with each other, wherein at least one conductive layer includes a portion whose cross-sectional area varies along the length direction of the at least one conductive layer. An angle between a line segment connecting two points on the same plane as the outer line of the width changing portion and a line segment parallel to the length direction of the at least one conductive layer is less than 90°. the

Another aspect of the present invention provides a flat panel display device, comprising a substrate, a TFT layer formed on the substrate, at least one insulating layer formed on the TFT layer, and a pixel layer, the pixel layer comprising The vias are electrically connected to more than one pixel of the TFT layer. The TFT layer includes a plurality of conductive layers crossing but not in contact with each other. The at least one conductive layer includes portions that vary in cross-sectional area along the length of the at least one conductive layer. An angle between a line segment connecting two points on the same plane as the outer line of the width changing portion and a line segment parallel to the length direction of the at least one conductive layer is less than 90°. the

Description of drawings

The above and other features and advantages of the present invention will be more apparent by describing the exemplary embodiments in detail with reference to the accompanying drawings. the

Fig. 1 A is the photo of the display area of conventional organic electroluminescence display device;

Figure 1B is a partial enlarged photo of the normal pixel marked as A in Figure 1A;

Figure 1C is a partially enlarged photo of the wrong pixel marked as B in Figure 1A;

Figure 1D is an enlarged bottom view of a portion of the pixel denoted B' in Figure 1C;

Figure 1E is a cross-sectional photo of a part of the pixel denoted as B' in Figure 1C;

2A is a schematic plan view of an organic electroluminescent display device according to an embodiment of the present invention;

Fig. 2B is the schematic circuit diagram of the pixel of the OELD device denoted as C in Fig. 2A;

2C is a partial cross-sectional view of a pixel denoted C in FIG. 2A according to one embodiment of the present invention;

Figure 2D is a partial plan view of a modified embodiment of a part shown in Figure 2C;

Figure 2E is a partially enlarged photo of the pixel in Figure 2C;

3A is a partial cross-sectional view of a pixel marked C in FIG. 2A according to another embodiment of the present invention;

Figure 3B is an enlarged view of a portion denoted D in Figure 3A according to an embodiment of the present invention;

FIG. 3C is a partially enlarged photograph of the pixel shown in FIG. 3A. the

Detailed ways

The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. the

Figure 2A is a schematic plan view of an organic electroluminescent display (OELD) device fabricated in accordance with the principles of the present invention. Referring to FIG. 2A, the substrate 110 includes a display area 200 on which a light emitting device such as an organic electroluminescent display device is disposed, and a sealing portion 800 of the substrate 110 is sealed with a sealing substrate (not shown) along the edge of the display area 200, And a terminal area 700 on which various terminals are arranged. However, the present invention is not limited thereto, and it may be embodied in various forms. For example, a sealing layer may be included which functions as a sealing portion. the

A driving power supply line 300 for supplying power to the display area 200 may be disposed between the display area 200 and the sealing part 800 . FIG. 2A shows an example of driving power supply lines of the present invention, but the present invention is not limited thereto. In order to ensure uniform brightness of the display area 200 , the driving power supply line 300 may surround the display area 200 to provide uniform driving power to the entire display area 200 . the

The driving power supply line 300 may be connected to a driving power line 310, which may be arranged across the display area 200, and electrically connected to the source electrode 170a (shown in FIG. 2C ) arranged under the protective layer 180 (shown in FIG. 2C ). Show). the

In addition, vertical and horizontal driving circuit units 500 and 600 may be arranged outside the boundary of the display area 200 . The vertical circuit unit 500 may be a scan driving circuit unit applying scan signals to the display area 200 , and the horizontal driving circuit unit 600 may be a data driving circuit unit applying data signals to the display area 200 . The vertical and horizontal driving circuit units 500 and 600 may be disposed outside the boundary of the sealing area as external integrated circuit (IC) or chip-on-glass (COG) units. the

The electrode power supply line 410 supplying the electrode power supply to the display area 200 may be arranged outside the boundary of the display area 200, and electrically connected to the first through hole 430 in the insulating layer formed between the electrode power supply line 410 and the second electrode layer. Two electrode layers, the second electrode layer is formed on the upper portion of the display area 200 . the

The drive power supply line 300, the electrode power supply line 410, and the vertical and horizontal drive circuit units 500 and 600 include terminals 320, 420, 520 and 620, respectively, and are electrically connected to the terminal area 700 arranged outside the boundary of the sealing area by lead wires . the

The display area 200 includes a plurality of pixels, which will be described below with reference to FIGS. 2B and 2C. FIG. 2B is a schematic circuit diagram of a pixel located at the nth column and the mth row of the OELD device denoted as C in FIG. 2A according to the embodiment of the present invention. the

As shown in FIG. 2B, a pixel includes five transistors and two capacitors, and each transistor is described as a PMOS TFT, but the present invention is not limited thereto. the

In use, the first scan signal and the second scan signal are input from the vertical circuit unit 500 to the display area 200 through a plurality of first scan lines and second scan lines respectively (see FIG. 2A ). The first scan signals S[n] and S[n-1] and the second scan signal E[n] are input through the first scan line and the second scan line, and the data voltage V _data[m] as a data signal is passed through the data The line input is in the pixel at column n and row m, denoted C in FIG. 2A.

The first TFT M1 supplies a current corresponding to a data voltage applied to the first TFT M1 through the second TFT M2 to an organic light emitting diode (OLED). the

The second TFT M2 switches the data voltage applied to the data line in response to the nth selection signal S[n] supplied from the first scan line. the

The third TFT M3 is diode-connected to the first TFT M1 in response to the (n-1)th selection signal S[n-1] applied to the first scan line. the

The fourth TFT M4 supplies a fixed voltage to one end of the first capacitor C1 in response to the (n-1)th selection signal S[n-1] applied to the first scan line. the

The fifth TFT M5 transfers the current supplied from the first TFT M1 to the OLED in response to the light emission signal E[n] applied to the second scan line. the

The first capacitor C1 maintains a portion of the voltage between the gate and source of the first TFT M1 for at least one frame, and the second capacitor C2 applies the data voltage as a compensated threshold voltage to the gate of the first TFT M1. the

The operation of the OELD device including the TFT layer and the pixel layer of this embodiment will be described below. The TFT layer may contain at least one TFT and other electronic components such as capacitors. The TFT layer can be regarded as a pixel circuit unit. the

When the (n-1)th selection signal S[n-1] is activated, the third TFT M3 is turned on, and then the first TFT M1, that is, the driving thin film transistor, enters a diode-connected state, and since the fifth TFT M5 is turned off, and the threshold voltage of the first TFT M1 is stored in the second capacitor C2. the

If the data voltage is input after the third TFT M3 is turned off in response to the (n-1)th selection signal S[n-1] and the first TFT M1 is turned on in response to the nth selection signal S[n], then the The corrected data voltage compensating for the threshold voltage is applied to the gate of the first TFT M1. the

At the same time, if the fifth TFT M5 is turned on in response to the nth light-emitting signal E[n], the current signal is transmitted to the OLED through the fifth TFT M5, and the OLED emits light. This current signal is applied to the gate of the first TFT M1. Pole voltage is adjusted. the

Fig. 2C is a partial cross-sectional view of OELD, OELD includes pixel layer R _P and TFT layer R _T , that is, electroluminescence unit and pixel layer, pixel layer includes first TFT M1 and fifth TFT M5, first TFT M1 is a driver The thin film transistor, the fifth TFT M5 is a switching thin film transistor that provides electrical signals for the pixel layer.

Referring to FIG. 2C , a TFT layer such as a first TFT M1 is formed on a portion of the substrate 110. The semiconductor active layer 130 of the first TFT M1 is formed on a portion of the upper surface of the buffer layer 120 formed on the surface of the substrate 110. The semiconductor active layer 130 may be an amorphous silicon layer or a polysilicon layer. Although not described in detail, the semiconductor active layer 130 includes source and drain regions doped with P-type or N-type dopants and a channel region. However, the thin film transistor including the semiconductor active layer 130 can be constructed in various ways. the

The gate electrode 150 of the first TFT M1 may be disposed on a portion of the semiconductor active layer 130. The gate electrode 150 is preferably composed of materials such as MoW and Al in view of contact with adjacent layers, surface smoothness of the stack, and processability, but is not limited thereto. the

A gate insulating layer 140 for insulating the gate electrode 150 from the semiconductor active layer 130 is disposed therebetween. The intermediate layer 160 as an insulating layer is a single layer or multiple layers and is formed on the gate electrode 150 and the gate insulating layer 140 . Source and drain electrodes 170a and 170b of the first TFT M1 are formed on the intermediate layer 160. The source and drain electrodes 170 a and 170 b may be formed of metal such as MoW, and heat-treated after being formed so as to make smooth ohmic contact with the semiconductor active layer 130 . the

The protective layer 180 is an insulating layer, which may consist of a passivation layer and/or a planarization layer, for protecting and/or leveling lower layers, and is formed on the source and drain electrodes 170a and 170b. As shown in FIG. 2C , the protection layer 180 can be a single layer composed of inorganic materials such as _SiNx or organic materials such as benzocyclobutene or acrylic, or a multilayer stack.

The first TFT M1 is electrically connected to the fifth TFT M5 functioning as a switching TFT through the extension unit 170c of the drain electrode 170b. The fifth semiconductor active layer 230 of the fifth TFT M5 is formed on the buffer layer 120 formed on the surface of the substrate 110 . The fifth semiconductor insulating layer 230 may be insulated from the second scan line and/or the fifth gate electrode 250 formed on the gate insulating layer 140 . The intermediate layer 160 and fifth source/drain electrodes 270a and 270b may be formed on the surface of the fifth gate electrode. The fifth source and drain electrodes 270 a and 270 b and the fifth semiconductor active layer 230 may be electrically connected through contact holes formed in the interlayer 160 and the gate insulating layer 140 . At least one protective layer 180 functioning as an insulating layer may be formed on the fifth source and drain electrodes 270a and 270b, including the pixel layer R of the first electrode layer 290, the electroluminescence unit 292, and the second electrode layer 400 stacked in sequence. _P may be formed on the protective layer 180 .

A method of forming the pixel layer R _P is described below. First, after the first electrode layer 290 is formed, the pixel defining layer 291 may be formed on the protective layer 180 outside the pixel open area 294 . The electroluminescence unit 292 including a light emitting layer may be disposed on the surface of the first electrode layer 290 of the pixel open area 294, and the second electrode layer 400 may be formed on the entire surface of the composite.

The electroluminescence unit 292 may be composed of a low molecular or polymer organic film. If the electroluminescent unit 292 is composed of a low-molecular organic film, the HIL, HTL, EML, ETL, and EIL can be laminated into a single structure or a composite structure, and low-molecular organic materials that can be used include copper phthalocyanine (CuPc), N, N'-Di(naphthalen-1-yl)-N,N'-diphenyl-benzidine (NPB), or aluminum tris-8-hydroxyquinolate (Alq3). A low-molecular organic film can be formed using an evaporation method. the

If the electroluminescence unit 292 is composed of a polymer organic film, it may include HTL and EML. HTL can be composed of PEDOT, while EML can be formed of poly-1,2-vinylidenephenyl (PPV) and polyfluorene. The polymeric organic film can be formed by various methods including, but not limited to, screen printing methods and inkjet printing methods. the

The second electrode layer 400 functions as a cathode, and may be deposited on the entire upper surface of the electroluminescence unit 292 . The second electrode layer 400 is not limited to be deposited on the entire upper surface. It can be formed of materials such as Al/Ca, ITO or Mg-Ag. The second electrode layer 400 may be formed in various forms such as multiple layers, and may further include an alkali-fluorinated or alkaline-earth fluorinated layer, such as a LiF layer. the

A first scan line and/or a scan line extension unit 240 (hereinafter referred to as a first scan line) may be formed between the first TFT M1 and the fifth TFT M5. The first scan line 240 may pass through the extension unit 170c of the drain electrode 170b of the first TFT M1 without contact. As shown in FIG. 2B, the first scan line 240 may be a conductive layer through which the (n-1)th selection signal S[n-1] is transmitted to the third and fourth TFTs M3 and M4, and The first scan line 240 includes a width varying portion A _w , whose width varies along the length direction of the first scan line due to different design specifications of the TFTs.

That is, as shown in a partial plan view of FIG _. 2C , the first scan line 240 may be formed as a conductive layer having an intersection area _Ac where the first scan line at least passes through but does not contact the extension unit 170c. The first scan line 240 may be disposed under the extension unit 170c extended from the drain electrode 170b. The first scan line 240 includes a width changing portion A _w whose width changes from the first width W _c to the second width W _w , or from the second width W _w to the first width W _c . The first width W _c and the second width W _w are different from each other, and the width W _c may be wider than the width W _w . The width variation portion A _w of the first scan line 240 may also be defined as a portion whose cross-sectional area varies along the length direction of the first scan line 240 .

The first scan line 240 may include one tab 241 at a region that does not cross the adjacent conductive layer 170c. Since the charge is concentrated on the tab 241 rather than the width changing portion _Aw , the generation of short circuit current in the width changing portion _Aw due to electrostatic discharge can be avoided.

The ratio of the effective width W _s of the tab 241 to the effective length W _d of the tab 241 may be smaller than the ratio of the second width W _w to the first width W _c so that static electricity is concentrated in the tab 241 . That is, W _s /W _d <W _w /W _c <1. Here, the first width W _c may be a measure of the maximum width of the width change portion, and the second width W _w may be a measure of the minimum width of the width change portion.

In this embodiment, the first scan line 240 may be a conductive layer, including the tab 241, and function as a gate electrode or a gate line. However, this is an exemplary embodiment of the present invention, and the present invention is not limited thereto. the

As shown in FIG. 2C , the tab 241 may be formed on the first scan line 240 (or the extended portion of the first scan line, that is, the conductive layer) extending toward the first TFT M1 . However, the tab 241 may be formed in many different forms as long as the tab 241 does not pass through adjacent conductive layers. In this way, the conductive layer connected to the tab 241 can be formed on the same layer of the source electrode and the drain electrode. The tab 241 may also extend in a direction relative to the first TFT M1. Alternatively, as shown in FIG. 2D , the tab 241 may be formed on the conductive layer including the width variation portion A _w and/or on the adjacent conductive layer.

FIG. 2E is a plan view of a partially enlarged photograph of the pixel shown in FIG. 2C. In FIG. 2E, tab 241 contacts the conductive layer region. In order to avoid and/or reduce electrostatic discharge, the area where the contact piece 241 contacts the conductive layer is far away from the area where the conductive layer overlaps. This structure can avoid or reduce electrostatic damage to the conductive layer of the TFT layer because the electrostatic discharge does not occur at the width changing portion _Aw but occurs at the tab 241 that does not intersect the conductive layer. In this way, short-circuit current faults between overlapping conductive layers and/or pixels can be avoided or reduced.

Figures 3A, 3B and 3C illustrate pixels of an OELD device fabricated in accordance with the principles of the present invention. A first scan line and/or a scan line extension unit 240 (hereinafter referred to as a first scan line) is formed between the first TFT M1 and the fifth TFT M5. The first scan line 240 passes through but does not contact the extension unit 170c of the drain electrode 170b of the first TFT M1. As shown in FIG. 2B, the first scan line 240 is a conductive layer to which the (n-1)th selection signal S[n-1] is transmitted, and the (n-1)th scan signal S[n-1] is transmitted. Refers to the third and fourth TFTs M3 and M4. The first scan line 240 may include a width varying portion A _w whose width varies in the length direction of the first scan line 240 . That is, as shown in the partial plan view shown in FIG. 3A , the first scan line 240 may be formed as a conductive layer having an intersection region _Ac passing through but not contacting at least the extension unit 170c extending from the drain electrode 170b. part. The first scan line may be disposed under the extension unit 170c. The first scan line 240 may include a width varying portion _Aw in the length direction of the first scan line 240, and the width of the width varying portion _Aw may continuously vary from _Wc to _Ww .

As shown in FIG. 3A, points denoted by reference numerals P1 and P2 (see FIG. 2B) located at the intersection of adjacent conductive layers are easily damaged by electrostatic discharge if the corresponding width-varying portions include sharp ends. However, in an embodiment of the present invention, the width variation portion A _w does not contain any sharp corner edges that may cause electrostatic discharge. In contrast, the width of the width varying portion A _w continuously varies along the first scan line 240 such that the width varying portion includes corner edges that are curved and are not at a 90° angle. Therefore, the charges causing electrostatic discharge are not concentrated in the width changing portion A _w , thereby avoiding or reducing electrostatic damage to the pixel.

The corners of the width changing portion A _w may preferably have obtuse angles and be rounded. Fig. 3B is an enlarged view of part D in Fig. 3A. Referring to Figure 3B, the angle θ is formed between the line segment O ₁ O ₂ and the line segment O ₁ O ₃ , the line segment O _{1 O 2} extending from the point O 1 to the point O ₂ , the two points at the width change that intersect each other but do not touch On the same plane of the part _Aw , the line segment O ₁ O ₃ extends from the point O ₁ to the point O ₃ , and the point O ₃ is located in the length direction of the first scanning line 240 . In order to avoid charge concentration on the edge of the first scan line 240, the angle θ between two line segments may be smaller than 45°.

FIG. 3C is a partially enlarged photograph of the pixel shown in FIG. 3A. Referring to FIG. 3C, since the width of the width variation portion A _w of the conductive layer passing through at least one adjacent conductive layer changes smoothly due to an obtuse angle, electrostatic damage to the conductive layer of the thin film transistor and/or the gap between adjacent conductive layers can be avoided. Short-circuit current, so the generation of wrong pixels can be avoided.

The above-mentioned embodiments are exemplary, and the present invention is not limited thereto. That is, the above-mentioned embodiments have been described with respect to the conductive layer formed in the extension portion between the drain electrode and the scan line, but the present invention can be applied to other conductive layers. Meanwhile, the present invention describes a TFT structure having five upper gate type transistors and two capacitors, and an OELD device including the TFT structure. However, the present invention can be modified in various forms as long as the conductive layer having the width changing portion is connected to the tab 241 at the conductive layer region not passing through the adjacent conductive layer. In addition, an angle between a line segment connecting corners of the width changing portion and a line segment parallel to the direction in which the conductive layer having the width changing portion extends may be smaller than 90°. The principles of the present invention can be applied to OELD devices and LCD devices regardless of the type of transistors. Further, the present invention can also be applied to electronic devices having a plurality of conductive layers crossing but not touching each other. the

The present invention may provide some or all of the advantages described below. First of all, including the tab 241 in the conductive layer region that does not pass through the adjacent conductive layer and using the tab-type conductive layer of the present invention in at least one TFT can avoid and/or reduce the time required for manufacturing and/or using the TFT. The generated static electricity damages the electrostatic discharge of the insulating layer formed between the conductive layers. the

Secondly, in a flat panel display device such as an OELD including a TFT layer, wherein the TFT layer includes a plurality of conductive layers, the tab 241 is connected to a conductive layer region that does not pass through an adjacent conductive layer, and the tab 241 is connected to at least one The conductive layer with the width varying portion, or connected to the adjacent conductive layer, which can avoid the generation of false pixels caused by the electrostatic discharge provided by the tab 241 . Such a structure can improve image quality. the

Third, a conductive layer containing more than one TFT may contain a portion thereof passing through but not touching an adjacent conductive layer. The conductive layer may include a width varying portion formed to substantially overlap the intersection region. The width of the width changing portion may be continuously changed so that corners of the width changing portion are obtuse angles. Since no sharp corner edges are present to concentrate electrostatic charges, damage to insulating layers formed between conductive layers due to electrostatic discharge can be avoided and/or reduced, thus avoiding product failure. the

Fourth, in a flat panel display device such as an OELD comprising one TFT layer, a conductive layer having a region crossing but not contacting an adjacent conductive layer may contain a width varying portion. Therefore, by avoiding the concentration of static electricity in the width variation portion, it is possible to reduce or eliminate the possibility of false pixel generation due to static electricity generated during the production or operation of the TFT. This can be achieved by continuously varying the width of the width varying portion and rounding the corners therein. Such a structure can avoid or reduce the generation of electrostatic charge in the width changing part, thereby improving the image quality. the

While the present invention has been shown and described with reference to exemplary embodiments thereof, those skilled in the art will understand that various changes in form and details do not depart from the spirit and scope of the invention as defined in the following claims. the

Claims (22)

1. An electronic device, comprising: the first conductive layer; and a second conductive layer intersecting the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the first conductive layer includes a width variation portion in a region where the first conductive layer intersects the second conductive layer, and the width of the width variation portion varies along the length direction of the first conductive layer, wherein the width of the second conductive layer is constant in the region where the first conductive layer intersects the second conductive layer, and wherein the angle between the line segment connecting two points on the same plane as the outer line of the width changing portion and the line segment parallel to the length direction of the first conductive layer is less than 90°, and the width of the width changing portion is along the The lengthwise direction of the first conductive layer changes continuously, and corners of the width changing portion are obtuse and rounded. 2. The electronic device according to claim 1, wherein the first conductive layer is a gate electrode of a TFT or an extension of a gate electrode of a TFT. 3. The electronic device according to claim 1, wherein the first conductive layer is a source electrode or a drain electrode of a TFT, or is an extension of a source electrode or a drain electrode of a TFT. 4. A TFT structure, comprising: the first conductive layer; and a second conductive layer intersecting the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the first conductive layer includes a width variation portion in a region where the first conductive layer intersects the second conductive layer, and the width of the width variation portion varies along the length direction of the first conductive layer, wherein the width of the second conductive layer is constant in the region where the first conductive layer intersects the second conductive layer, and wherein the angle between the line segment connecting two points on the same plane as the outer line of the width changing portion and the line segment parallel to the length direction of the first conductive layer is less than 90°, and the width of the width changing portion is along the The lengthwise direction of the first conductive layer changes continuously, and corners of the width changing portion are obtuse and rounded. 5. The TFT structure of claim 4, wherein the first conductive layer is a gate electrode of a TFT or an extension of the gate electrode. 6. The TFT structure according to claim 4, wherein the first conductive layer is a source electrode or a drain electrode of a TFT, or is an extension of a source electrode or a drain electrode of a TFT. 7. A flat panel display device, comprising: Substrate; a TFT layer formed on the substrate; and a pixel layer comprising more than one pixel electrically connected to the TFT layer, Wherein the TFT layer includes a first conductive layer and a second conductive layer crossing the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, wherein the first conductive layer includes a width variation portion in a region where the first conductive layer intersects the second conductive layer, and the width of the width variation portion varies along the length direction of the first conductive layer, wherein the width of the second conductive layer is constant in the region where the first conductive layer intersects the second conductive layer, and Wherein the angle between the line segment connecting two points on the same plane of the outer line of the width changing part and the line segment parallel to the length direction of the first conductive layer is less than 90°, the width of the width changing part is along the width of the width changing part The length direction of the first conductive layer changes continuously, and the corners of the width changing portion are obtuse and rounded. 8. The flat panel display device according to claim 7, wherein the first conductive layer is a gate electrode. 9. The flat panel display device according to claim 7, wherein the first conductive layer is a source electrode or a drain electrode. 10. The flat panel display device according to claim 7, wherein the pixel layer comprises: first electrode; an electroluminescent cell formed on the first electrode; and The second electrode is formed on the electroluminescence unit. 11. The flat panel display device of claim 7, further comprising at least one insulating layer formed on the TFT layer, wherein pixels of the pixel layer are electrically connected to the TFT layer through contact holes formed in the at least one insulating layer. 12. An electronic device comprising: the first conductive layer; and a second conductive layer intersecting the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, Wherein the first conductive layer includes a part whose cross-sectional area changes along the length direction of the first conductive layer, and the part is in a region where the first conductive layer intersects with the second conductive layer, wherein the width of the second conductive layer is constant in the region where the first conductive layer intersects the second conductive layer, and Wherein the angle between the line segment connecting two points located on the same plane as the outer line of the cross-sectional area and the line segment parallel to the length direction of the first conductive layer is less than 90°, the width of the cross-sectional area is along the The length direction of the first conductive layer changes continuously, and the corners of the cross-sectional area are obtuse and rounded. 13. The electronic device according to claim 12, wherein the first conductive layer is a gate electrode of a TFT or an extension of a gate electrode of a TFT. 14. The electronic device according to claim 12, wherein the first conductive layer is a source electrode or a drain electrode of a TFT, or an extension of a source electrode or a drain electrode of a TFT. 15. A TFT structure comprising: the first conductive layer; and a second conductive layer intersecting the first conductive layer, wherein the first conductive layer does not contact the second conductive layer, Wherein the first conductive layer includes a part whose cross-sectional area changes along the length direction of the first conductive layer, and the part is in a region where the first conductive layer intersects with the second conductive layer, wherein the width of the second conductive layer is constant in the region where the first conductive layer intersects the second conductive layer, and Wherein the angle between the line segment connecting two points located on the same plane as the outer line of the cross-sectional area and the line segment parallel to the length direction of the first conductive layer is less than 90°, the width of the cross-sectional area is along the The length direction of the first conductive layer changes continuously, and the corners of the cross-sectional area are obtuse and rounded. 16. The TFT structure of claim 15, wherein the first conductive layer is a gate electrode of a TFT or an extension of a gate electrode of a TFT. 17. The TFT structure according to claim 15, wherein the first conductive layer is a source electrode or a drain electrode of a TFT, or an extension of a source electrode or a drain electrode of a TFT. 18. A flat panel display device comprising: Substrate; a TFT layer formed on the substrate; and a pixel layer comprising more than one pixel electrically connected to the TFT layer, Wherein the TFT layer includes a first conductive layer and a second conductive layer crossing the first conductive layer, Wherein the first conductive layer does not contact the second conductive layer, wherein the first conductive layer includes a portion whose cross-sectional area changes along the length direction of the first conductive layer, the portion is in the first conductive layer In the region intersecting with the second conductive layer, wherein the width of the second conductive layer is constant in the region where the first conductive layer intersects the second conductive layer, and Wherein the angle between the line segment connecting two points located on the same plane as the outer line of the cross-sectional area and the line segment parallel to the length direction of the first conductive layer is less than 90°, the width of the cross-sectional area is along the The length direction of the first conductive layer changes continuously, and the corners of the cross-sectional area are obtuse and rounded. 19. The flat panel display device of claim 18, wherein the first conductive layer is a gate electrode. 20. The flat panel display device of claim 18, wherein the first conductive layer is a source electrode or a drain electrode. 21. The flat panel display device of claim 18, wherein the pixel layer comprises: first electrode; an electroluminescent cell formed over the first electrode; and A second electrode is formed on the electroluminescence unit. 22. The flat panel display device of claim 18, further comprising at least one insulating layer formed on the TFT layer, wherein pixels of the pixel layer are electrically connected to the TFT layer through contact holes formed in the at least one insulating layer.

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