KR100979263B1 - Driving Thin Film Transistor for Active Matrix type Organic Light Emitting Diode Device and Active Matrix type Organic Light Emitting Diode Device having the Driving Thin Film Transistor - Google Patents

Abstract

In the present invention, in order to provide a bottom gate structure AMOLED thin film transistor with improved device reliability and an AMOLED including the thin film transistor, a spaced interval between the source electrode and the drain electrode is formed in a ring or annular structure. Since the channel width has a value corresponding to the channel circumferential length, and the channel length corresponds to the separation interval between the source electrode and the drain electrode, the gate, source, and drain structures different from those of the related art are taken to increase the device reliability, thereby improving the amorphous silicon material. By dramatically improving the reliability of the bottom gate type thin film transistor used as a semiconductor layer, it can be easily applied as a driving thin film transistor for AMOLED, and by applying the existing amorphous silicon thin film transistor as a driving thin film transistor for AMOLED, The benefits that can increase the ripple effect Have

Description

(Driving Thin Film Transistor for Active Matrix Type Organic Light Emitting Diode Device and Active Matrix Type Organic Light Emitting Diode including the driving thin film transistor for active matrix type organic light emitting diode and the driving thin film transistor) Device having the Driving Thin Film Transistor}             

1 is a cross-sectional view of a conventional organic light emitting device panel.

2 is an equivalent circuit diagram of one pixel portion of a general AMOLED.

3A and 3B are views of a conventional thin film transistor for driving AMOLED, FIG. 3A is a plan view, and FIG. 3B is a cross-sectional view showing a section cut along the cutting line IIIb-IIIb of FIG. 3A.

4A and 4B are views illustrating a driving thin film transistor for AMOLED according to a first embodiment of the present invention. FIG. 4A is a plan view, and FIG. 4B is a cross-sectional view taken along the cutting line IVb-IVb of FIG. 4A. One section.

5A and 5B are views illustrating a driving thin film transistor for AMOLED according to a second embodiment of the present invention. FIG. 5A is a plan view, and FIG. 5B is a cross-sectional view taken along the cutting line Vb-Vb of FIG. 5A. One section.                 

6 to 8 are drawings of a driving thin film transistor for AMOLED according to a third embodiment of the present invention.

9 is a plan view of an AMOLED according to a fourth embodiment of the present invention.

10 is a plan view of an AMOLED according to a fifth embodiment of the present invention;

Description of the Related Art

110 substrate 112 gate electrode

116: semiconductor layer 118: source electrode

120: drain electrode

ch: channel

W: channel width

L: Channel Length

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting diode device (hereinafter abbreviated as AMOLED), and to a thin film transistor for driving an active matrix organic light emitting diode.

In the field of flat panel display (FPD) including the organic light emitting device, a liquid crystal display device (LCD) has been the most noticeable display device until now, but the liquid crystal display device Since the light-receiving device, not the light-emitting device, has technical limitations such as brightness, contrast, viewing angle, and large area, development of a new flat panel display device capable of overcoming these disadvantages is being actively developed.

The organic light emitting display device, which is one of the new flat panel displays, has a better viewing angle, contrast, and the like than a liquid crystal display because it is self-luminous, and is lightweight and thinner because it does not require a backlight. In addition, since it is possible to drive DC low voltage, fast response speed, and all solid, it is strong against external shock, wide use temperature range, and especially inexpensive in terms of manufacturing cost.

In particular, unlike the liquid crystal display device or the plasma display panel (PDP), all of the deposition and encapsulation equipments are manufactured in the organic electroluminescent device manufacturing process. Therefore, the process is very simple.

In particular, when the organic light emitting display device is driven by an active matrix method having a thin film transistor as a switching device for each pixel, the same luminance is displayed even when a low current is applied, and thus, low power consumption, high definition, and large size can be obtained.

Hereinafter, the basic structure and operation characteristics of the active matrix organic electroluminescent device (hereinafter abbreviated as AMOLED) will be described in detail with reference to the drawings.

1 is an overall cross-sectional view of a conventional AMOLED.                         

As illustrated, the first and second substrates 10 and 60 are disposed to face each other, and the thin film transistor T is included on the first substrate 10 for each pixel region P, which is a minimum unit for implementing a screen. An array element layer AL is formed, and an organic light emitting diode having a structure in which a first electrode 48, an organic light emitting layer 54, and a second electrode 56 are sequentially stacked on the array element layer AL. The diode element E is formed. The light emitted from the organic light emitting layer 54 is emitted toward the transmissive electrode of the first and second electrodes 48 and 56, and may be classified into an upper light emitting method or a lower light emitting method. The bottom emission type structure in which the light emitted from the organic light emitting layer 54 selected from the light-transmitting material is emitted toward the first electrode 48 is provided.

In addition, the second substrate 60 is a kind of encapsulation substrate, and a recess 62 is formed therein, and an organic light emitting diode device is blocked in the recess 62 to absorb moisture from the outside. The moisture absorbent 64 for protecting (E) is enclosed.

Edge portions of the first and second substrates 10 and 60 are sealed by a seal pattern 70.

2 is an equivalent circuit diagram of one pixel portion of a general AMOLED.

As shown, a gate line (GL) is formed in which a scan signal is applied in a first direction, and a data line (DL) in which image signals are applied to be spaced apart from each other in a second direction crossing the first direction; A power supply line PL to which a data line and a power signal are applied is formed, and an area where the gate line GL, the data line DL, and the power supply line PL intersect is a pixel area. It is defined as (P).

In the pixel region P, a switching thin film transistor (Ts) for controlling a voltage applied from the gate line GL and the data line DL, and a switching thin film transistor Ts of the switching thin film transistor Ts. A driving thin film transistor Td for controlling light emission luminance is formed by using one of the driving electrodes and the voltage applied from the power supply line PL.

The driving electrode for the switch thin film transistor Ts forms a storage capacitor (hereinafter referred to as Cst) with the power supply line PL.

An organic light emitting diode (E) element is formed in connection with the driving thin film transistor Td.

In the conventional AMOLED thin film transistor structure, as shown in FIG. 1, a top gate structure using a polysilicon material as a semiconductor device is mainly used, but recently, an amorphous silicon material is used for the purpose of process simplification and cost reduction. A bottom gate structure using a semiconductor device as a semiconductor device has been proposed.

3A and 3B are views of a conventional thin film transistor for driving AMOLED. FIG. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along the cut line IIIb-IIIb of FIG. 3A.

As shown, a gate electrode 82 is formed on the substrate 80, a gate insulating film 84 is formed in a region covering the gate electrode 82, and a gate over the gate insulating film 84. The semiconductor layer 86 is formed in an area covering the electrode 82, and the source electrode 88 and the drain electrode 90 are formed on the semiconductor layer 86 so as to be spaced apart from each other.

The source electrode 88 and the drain electrode 90 are positioned to overlap both sides of the gate electrode 82 at a predetermined interval.

The semiconductor layer 86 includes an active layer 86a made of pure amorphous silicon material and an ohmic contact layer 86b made of impurity amorphous silicon material, and a section between the source electrode 88 and the drain electrode 90. An impurity amorphous silicon material is removed and a channel ch is formed in which the active layer material constituting the lower layer is exposed.

The channel width W is a direction orthogonal to the carrier movement direction, and the channel length L has a value corresponding to the separation distance between the source electrode 88 and the drain electrode 90.

The conventional bottom gate structure thin film transistor has a source electrode and a drain electrode partitioned, and when the thin film transistor having such a structure is used as a driving thin film transistor for AMOLED, the instability of the amorphous silicon material itself and Due to the structural factors of the thin film transistor itself due to the field concentration phenomenon, the characteristics of the thin film transistor element deteriorate with time, thereby causing a problem in device reliability.

 In order to solve the above problems, an object of the present invention is to provide a thin film transistor for the bottom gate structure AMOLED using an amorphous silicon material with improved device reliability.

To this end, in the present invention, since the channel width corresponds to the direction crossing the carrier movement direction, the separation section between the source electrode and the drain electrode is formed in an annular shape or a structure applied here, so that the channel width is Since the channel length corresponds to the separation distance between the source electrode and the drain electrode with a value corresponding to the circumferential length, the device reliability is improved by taking a gate, source, and drain structure different from the conventional method.

In addition, another object of the present invention is to provide a thin film transistor for AMOLED having a compact structure while improving device reliability.

To this end, the present invention is to form the source electrode and the drain electrode in a concentric polygonal structure.

In order to achieve the above object, in a first aspect of the present invention, an organic electroluminescent device for driving an organic light emitting diode device comprising an array element layer including a driving thin film transistor and an organic light emitting diode element connected to the driving thin film transistor. A thin film transistor, comprising: a gate electrode formed on a substrate; A semiconductor layer formed in a region covering the gate electrode and having a structure in which a pure amorphous silicon material layer and an impurity amorphous silicon material layer are sequentially stacked; A first driving electrode having a circular pattern structure positioned at a central portion on the semiconductor layer; A structure surrounding the first driving electrode, the second driving electrode having an annular shape spaced apart from the first driving electrode by a predetermined distance, wherein the first driving electrode is any one of a source electrode and a drain electrode, The second driving electrode is the other of the source electrode and the drain electrode, and the organic light emitting diode device is characterized in that a channel consisting of a pure semiconductor material region is formed in the interval between the first and second driving electrodes. Provides a thin film transistor for.

According to a second aspect of the present invention, there is provided a thin film transistor for driving an organic electroluminescent element comprising an array element layer including a driving thin film transistor and an organic light emitting diode element connected to the driving thin film transistor. A gate electrode formed on the; A semiconductor layer formed in a region covering the gate electrode and having a structure in which a pure amorphous silicon material layer and an impurity amorphous silicon material layer are sequentially stacked; A first driving electrode having a polygonal pattern structure positioned at a central portion on the semiconductor layer; A structure surrounding the first driving electrode, the second driving electrode being spaced apart from the first driving electrode at a predetermined interval and having a polygonal frame shape, wherein the first driving electrode is any one of a source electrode and a drain electrode. And the second driving electrode is the other of the source electrode and the drain electrode, and an organic electroluminescent light emitting device, characterized in that a channel composed of a pure amorphous silicon material region is formed in the interval between the first and second driving electrodes. Provided is a thin film transistor for driving a diode element.

The width of the channel according to the first and second features corresponds to a circumferential length at an intermediate point of an inner side of the first pattern and an outer side of the second pattern, and the length of the channel is a separation distance between the source electrode and the drain electrode. And having a value corresponding to.

According to the second aspect, the first and second driving electrodes may have any one of a square, a triangle, and a cross pattern structure.

The driving semiconductor layer according to the first and second features may include a plurality of divided patterns forming a radial structure, and the plurality of channels may correspond to the channels at positions corresponding to the plurality of semiconductor layers. A plurality of thin film transistors are connected in a parallel structure to form one driving thin film transistor.

According to a third aspect of the present invention, there is provided a semiconductor device comprising: a gate wiring formed in a first direction; Data and power lines formed in a second direction crossing the first direction and spaced apart from each other; A switching thin film transistor positioned at an intersection point of the gate wiring and the data wiring, the switching thin film transistor comprising a switching gate electrode, a switching semiconductor layer, a switching source electrode, and a switching drain electrode; A driving gate electrode connected to the switching drain electrode; A driving semiconductor layer formed in a region covering the driving gate electrode; A source electrode formed of any one of a circular or polygonal structure in a central portion of the driving semiconductor layer and connected to a power electrode branched from the power wire; A drain electrode having a structure surrounding a region excluding a connection portion of the source electrode with a power electrode, spaced apart from the source electrode at a predetermined interval, and having any one of an annular shape or a polygonal frame shape; A region where the gate wiring, the data wiring, and the power wiring cross each other is defined as a pixel region, and includes an electrode for an organic light emitting diode device formed in the pixel region by being connected to the drain electrode, and spaced apart from the source electrode and the drain electrode. A channel, which is a region in which pure amorphous silicon material of the semiconductor layer is exposed, is formed in the section, and the driving gate electrode, the driving semiconductor layer, the driving source electrode, and the driving drain electrode form a driving thin film transistor. An organic electroluminescent device is provided.

According to a fourth aspect of the present invention, there is provided a semiconductor device comprising: a gate wiring formed in a first direction; Data and power lines formed in a second direction crossing the first direction and spaced apart from each other; A switching thin film transistor positioned at an intersection point of the gate wiring and the data wiring, the switching thin film transistor comprising a switching gate electrode, a switching semiconductor layer, a switching source electrode, and a switching drain electrode; A driving gate electrode connected to the switching drain electrode; A driving semiconductor layer formed in a region covering the driving gate electrode; A drain electrode formed of any one of a circular or polygonal structure in a central portion of the driving semiconductor layer; An area where the gate line, the data line, and the power line cross each other is defined as a pixel area, and is connected to the drain electrode and formed in the pixel area; It has a structure surrounding the region except for the connection between the drain electrode and the electrode for the organic light emitting diode device, spaced apart from the drain electrode at regular intervals, and has any one of an annular or polygonal frame shape, branched from the power wiring And a source electrode connected to a power electrode, wherein a channel, which is a region in which pure amorphous silicon material of the semiconductor layer is exposed, is formed in a spaced interval between the source electrode and the drain electrode, and includes the driving gate electrode, the driving semiconductor layer, and the driving electrode. The source electrode and the driving drain electrode provide an organic light emitting display device, which comprises a driving thin film transistor.

The width of the channel according to the third and fourth features is a circumferential length at an intermediate point between the source electrode and the drain electrode, and the length of the channel corresponds to a separation distance between the source electrode and the drain electrode. The organic light emitting diode device includes a first electrode connected to the drain electrode, an organic light emitting layer, and a second electrode, and the driving semiconductor layer comprises a plurality of divided patterns forming a radial structure. In a position corresponding to the plurality of semiconductor layers, the channel is formed in plural, and a plurality of thin film transistors are connected in parallel to correspond to the channel to form one driving thin film transistor.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

In one embodiment of the present invention, an embodiment of a thin film transistor for driving an annular channel structure AMOLED.

First Embodiment

4A and 4B are views illustrating a driving thin film transistor for AMOLED according to a first embodiment of the present invention. FIG. 4A is a plan view, and FIG. 4B is a cross-sectional view taken along the cutting line IVb-IVb of FIG. 4A. One cross section.                     

As illustrated, a gate electrode 112 is formed on the substrate 110, a gate insulating layer 114 is formed in an area covering the gate electrode 112, and a gate electrode (or an upper portion of the gate insulating layer 114). In the region covering 112, a semiconductor layer 116 having a structure in which a pure amorphous silicon material layer and an impurity amorphous silicon material layer are sequentially stacked is formed, and a center region of the gate electrode 112 on the semiconductor layer 116 is formed. At a corresponding position, a circular source electrode 118 and an annular drain electrode 120 are formed to be spaced apart from each other by a structure surrounding the source electrode 118.

In the spaced interval between the source electrode 118 and the drain electrode 120, a pure semiconductor material of the semiconductor layer 116 is exposed, the channel (ch) having an annular shape according to the pattern shape between the two electrodes is configured It is characterized by.

The channel width W has a value corresponding to the circumferential length of the channel between the source electrode 118 and the drain electrode 120, and the channel length L is a separation distance between the source electrode 118 and the drain electrode 120. In this case, the W / L ratio can be improved over the existing structure by adopting a gate, source, and drain structure different from those of the related art.

According to the present embodiment structure, since the channel ch does not have an angular edge portion, it is possible to prevent the field from being concentrated in the existing channel edge portion, thereby improving device life.

In the present exemplary embodiment, the gate electrode 112 and the semiconductor layer 116 are formed in a circular pattern structure to correspond to the source electrode 118 and the drain electrode 120, but are not limited to the circular pattern structure.                     

In addition, the circular pattern includes an elliptical structure.

In this invention, the case where the position of the said source electrode and the drain electrode is mutually changed is also included.

Hereinafter, in another embodiment of the present invention, the interval between the source electrode and the drain electrode is configured in an annular shape, but the semiconductor layer is formed in a plurality of patterns for driving the AMOLED comprising a plurality of thin film transistors connected in a parallel structure. An embodiment of a thin film transistor structure.

Second Embodiment

5A and 5B are views illustrating a driving thin film transistor for AMOLED according to a second embodiment of the present invention. FIG. 5A is a plan view, and FIG. 5B is a cross-sectional view taken along the cutting line Vb-Vb of FIG. 5A. One cross section.

As illustrated, a gate electrode 212 having a circular open portion 211 is formed on the substrate 210, and a gate insulating film 214 is formed on the entire surface of the substrate covering the gate electrode 212. A plurality of semiconductor layers 216a, 216b, 216c, and 216d having an island pattern structure are formed to be spaced apart from each other in a radial structure on the gate insulating layer 214 to cover a width direction region of the gate electrode 212. A source electrode 218 having a circular structure in a region covering the circular open portion 211 at a position overlapping an inner portion of the gate electrode 212 at a predetermined interval on the upper portions 216a, 216b, 216c, and 216d, and a source electrode An annular drain electrode 220 overlapping the outer side of the gate electrode 212 by a predetermined structure is formed in a structure surrounding the 218.

In this case, the ends of each of the plurality of semiconductor layers 216a, 216b, 216c, and 216d are positioned to overlap the source electrode 218 and the drain electrode 220.

In the present embodiment, since the four semiconductor layers 216a, 216b, 216c, and 216d are located in the annular standoff area SA formed by the source electrode 218 and the drain electrode 220, the semiconductor layer 216a. , The first to fourth thin film transistors T1 having a parallel structure in which the separation areas SA including the second gates 216b, 216c, and 216d form the respective channels ch1, ch2, ch3, and ch4, and to which the same gate signal is applied. T2, T3, and T4).

That is, since the current of the thin film transistor for driving is calculated as the sum of the currents in the first to fourth thin film transistors, the current supply amount can be increased compared to the conventional thin film transistor, so that the driving capability can be improved.

In addition, by dispersing and driving a plurality of thin film transistors, damage to the thin film transistors can be minimized, thereby increasing device stability of the thin film transistors.

In the thin film transistor structure according to the first and second embodiments, since the source electrode and the drain electrode positioned in the upper layer have a circular structure, the first embodiment is applied as the basic structure to increase the space utilization of the pixel region. However, it is an embodiment in which the pattern of the source electrode and the drain electrode is modified in a compact structure.                     

Third Embodiment

6 to 8 are diagrams illustrating a thin film transistor for driving AMOLEDs according to a third embodiment of the present invention. FIG. 6A includes a rectangular frame channel, FIG. 6B a triangular frame channel, and FIG. 6C includes a cross channel. The cross-sectional structure can be applied to the structure shown in FIG. 4B, and therefore, a planar structure will be described.

FIG. 6 illustrates a structure in which a source electrode 318 is formed in a quadrangular shape and surrounds the source electrode 318. The drain electrode 320 having a rectangular frame shape is formed in the shape of the source electrode 318. The channel ch positioned in the separation region between the drain electrode 320 and the drain electrode 320 has a rectangular frame shape.

The channel width W and the channel length L, as in the first embodiment, have a circumferential length at an intermediate point between the outer side of the source electrode 318 and the outer side of the drain electrode 320. Since the separation distance between the source electrode 318 and the drain electrode 320 corresponds to the channel length L, the W / L ratio may be increased compared to the existing structure, thereby improving driving capability.

In the present embodiment, since the outer shape of the drain electrode 320 positioned at the outermost part is formed in a quadrangle, when the AMOLED is applied to the AMOLED, it can be formed in a compact structure in the pixel area, thereby improving the aperture ratio.

FIG. 7 illustrates a structure modified from the structure of FIG. 6A, wherein the source electrode 418 is formed in a triangular pattern, and the drain electrode 420 is formed in a triangular frame with a structure surrounding the source electrode 418. The channel ch between the electrodes is formed in a triangular frame shape, and the drain electrode 420 which is the outermost electrode is formed in a triangle.                     

In FIG. 8, the source electrode 518 is formed in a rectangular pattern, and the drain electrode 520 is formed in a cross-shaped frame having a structure surrounding the source electrode 518 and having a cross-shaped open portion 519. .

According to this structure, since the outer shape of the drain electrode, which is the outermost driving electrode, includes a plurality of concave portions and convex portions, it may be easy to form a compact structure with neighboring devices when applied to the AMOLED.

In this embodiment, the shape of the channel is kept in an annular shape, and an example in which the outermost drive electrode is deformed into a concentric polygonal structure is also included.

In addition, the thin film transistor for driving may be fabricated using a plurality of thin film transistors connected in parallel by applying the structure of the second embodiment to the semiconductor layer.

As described above, according to the concentric circles or the concentric polygonal bottom gate structure thin film transistors according to the present embodiments, since the driving capability can be improved than before, the thin film transistor for driving AMOLED can be easily applied.

Hereinafter, another embodiment of the present invention is an embodiment in which the concentric thin film transistor is applied as a driving thin film transistor for AMOLED.

Fourth Embodiment

FIG. 9 is a plan view of an AMOLED according to a fourth embodiment of the present invention, and includes a driving thin film transistor in which the characteristic structure of the concentric thin film transistor according to the first embodiment is applied.

As shown, the gate wiring 612 is formed in the first direction, and the data wiring 614 and the power supply wiring 616 are formed to be spaced apart from each other in the second direction crossing the first direction. An area where the gate wiring 612, the data wiring 614, and the power supply wiring 616 cross each other is defined as a pixel area P.

At the point where the gate wiring 612 and the data wiring 614 intersect, the switching gate electrode 618, the switching semiconductor layer 620, the switching source electrode 622, and the switching drain electrode 624 are formed. The switching thin film transistor Ts is formed, and in the switching drain electrode 624, the capacitor electrode 626 extends in a region overlapping with the power supply wiring 616 and is separate from the switching drain electrode 624. The driving gate electrode 628 is connected through the contact hole, and the driving semiconductor layer 630 is formed in an area covering the driving gate electrode 628 and corresponds to the center of the driving gate electrode 628. The drive source electrode 632 has a circular structure.

At this time, the driving source electrode 632 has a first projecting part (PP1) on one side, and is separate from the power electrode 634 branched from the power supply wiring 616 through the first projecting part (PP1). It is electrically connected through the contact hole.

The driving source electrode 632 has a structure surrounding the driving source electrode 632, and an annular driving drain electrode 638 is formed to overlap the outer side of the driving gate electrode 628 at a predetermined interval. In this case, in order to prevent a short circuit from the driving source electrode 632, the driving unit may be spaced apart from the first protrusion PP1 of the driving source electrode 632.

It characterized in that the channel (ch) located in the separation section between the driving drain electrode 638 and the driving source electrode 632 has an annular shape, the drive capability by the increase in the W / L ratio by this structural feature Can increase.

However, the structure of the driving source electrode 632 and the driving drain electrode 638 is not limited to the present embodiment structure, and may be variously modified and applied to the above described first to third embodiment structures. In this case, a connection part for a connection between the driving source electrode 632 and the power electrode 634 and a connection between the driving drain electrode 638 and the electrode for the organic light emitting diode device 640 includes a channel (ch). Retains the features of annular or annularly deformed structures.

The driving gate electrode 628, the driving semiconductor layer 630, the driving source electrode 632, and the driving drain electrode 638 form a driving thin film transistor Td.

One outer side of the driving drain electrode 638 has another second protrusion PP2, and the electrode 640 for the organic light emitting diode device is connected through the second protrusion PP2.

In addition, one side of the switching drain electrode 624 forms a capacitor electrode 626 extending to an area overlapping the power supply wiring 616, and the power supply wiring 616 and the capacitor electrode 626 overlap each other. Area constitutes a storage capacitor Cst.

Hereinafter, another embodiment of the present invention is an embodiment of a structure in which the driving source electrode and the driving drain electrode are replaced with each other although the basic structure is the same as that of the fourth embodiment.

Fifth Embodiment

FIG. 10 is a plan view of an AMOLED according to a fifth embodiment of the present invention, and will be described with reference to characteristic parts distinguishing from the fourth embodiment.

The driving thin film transistor Td according to the present embodiment has a circular pattern in a central portion, and has a driving drain electrode 738 having a first protrusion PP1 extending to one side, and the driving drain electrode 738. ) And a driving source electrode 732 having an annular shape and having a second protrusion PP2 extending to a position overlapping with the power electrode 734.

The driving source electrode 732 is positioned to be spaced apart from the first protrusion PP1 of the driving drain electrode 738, and is located at a separation interval between the driving source electrode 732 and the driving drain electrode 738. The channel (ch) is characterized in that it has an annular structure.

The driving drain electrode 738 is connected to the organic light emitting diode device electrode 740 through the first protrusion PP1, and the driving source electrode 732 is connected to the power electrode through the second protrusion PP2. 734).

As described above, in the annular structure thin film transistor according to the present invention, the position of the driving source electrode and the driving drain electrode may be changed from each other, and the pattern may be changed to connect the elements connected to each electrode, but basically In a bottom gate structure thin film transistor using a semiconductor material made of an amorphous silicon material, it is important to apply the first to third embodiment structures as the channel shape and the pattern structure of the outermost driving electrode.

The electrode for an organic light emitting diode device mentioned in the fourth and fifth embodiments is either an anode electrode or a cathode electrode, and although not shown in the drawings, an organic light emitting layer and an upper portion of the organic light emitting diode device electrode are not shown. One electrode for an organic light emitting diode element is formed in sequence.

However, the present invention is not limited to the above embodiments and can be practiced in various ways without departing from the spirit of the present invention.

For example, in an embodiment in which the source electrode and the drain electrode are formed in a polygonal structure, the polygonal structures of the source electrode and the drain electrode are not limited to polygonal polygonal structures that resemble each other.

As described above, according to the concentric or concentric polygonal structure thin film transistor according to the present invention, by dramatically improving the reliability of the bottom gate type thin film transistor using an amorphous silicon material as a semiconductor layer, it is easily applied as a driving thin film transistor for AMOLED. In addition, by applying the existing amorphous silicon thin film transistor as a driving thin film transistor for AMOLED has the advantage that can increase the ripple effect in the related field.

Claims (10)

A thin film transistor for driving an organic light emitting device comprising an array element layer including a driving thin film transistor and an organic light emitting diode device connected to the driving thin film transistor, A gate electrode formed on the substrate; A semiconductor layer formed in a region covering the gate electrode and having a structure in which a pure amorphous silicon material layer and an impurity amorphous silicon material layer are sequentially stacked; A first driving electrode having a circular pattern structure positioned at a central portion on the semiconductor layer; A second driving electrode having a structure surrounding the first driving electrode and having an annular shape spaced apart from the first driving electrode at a predetermined interval; The first driving electrode may be any one of a source electrode and a drain electrode, and the second driving electrode may be the other one of the source electrode and the drain electrode, and may be spaced apart from the first and second driving electrodes. A thin film transistor for driving an organic light emitting diode device, characterized in that a channel consisting of a pure semiconductor material region. A thin film transistor for driving an organic light emitting device comprising an array element layer including a driving thin film transistor and an organic light emitting diode device connected to the driving thin film transistor, A gate electrode formed on the substrate; A semiconductor layer formed in a region covering the gate electrode and having a structure in which a pure amorphous silicon material layer and an impurity amorphous silicon material layer are sequentially stacked; A first driving electrode having a polygonal pattern structure positioned at a central portion on the semiconductor layer; A second driving electrode having a structure surrounding the first driving electrode and positioned spaced apart from the first driving electrode at a predetermined interval and having a polygonal frame shape. The first driving electrode may be any one of a source electrode and a drain electrode, and the second driving electrode may be the other one of the source electrode and the drain electrode, and may be spaced apart from the first and second driving electrodes. A thin film transistor for driving an organic light emitting diode device, characterized in that a channel consisting of a pure amorphous silicon material region. The method according to claim 1 or 2, The width of the channel corresponds to a circumferential length at an intermediate point of an inner side of the first pattern and an outer side of the second pattern, and the length of the channel has a value corresponding to a separation distance between the source electrode and the drain electrode. A thin film transistor for driving an organic light emitting diode device. The method of claim 2, The thin film transistor for driving the organic light emitting diode device, wherein the first and second driving electrodes have any one of a square, a triangle, and a cross pattern structure. The method according to claim 1 or 2, The driving semiconductor layer is formed of a plurality of divided patterns forming a radial structure, and at a position corresponding to the plurality of semiconductor layers, the channel is composed of a plurality of thin film transistors in parallel to correspond to the channel. A thin film transistor for driving an organic light emitting diode device which is connected to form a single thin film transistor for driving. A gate wiring formed in a first direction; Data and power lines formed in a second direction crossing the first direction and spaced apart from each other; A switching thin film transistor positioned at an intersection point of the gate wiring and the data wiring, the switching thin film transistor comprising a switching gate electrode, a switching semiconductor layer, a switching source electrode, and a switching drain electrode; A driving gate electrode connected to the switching drain electrode; A driving semiconductor layer formed in a region covering the driving gate electrode; A source electrode formed of any one of a circular or polygonal structure in a central portion of the driving semiconductor layer and connected to a power electrode branched from the power wire; A drain electrode having a structure surrounding a region excluding a connection portion of the source electrode with a power electrode, spaced apart from the source electrode at a predetermined interval, and having any one of an annular shape or a polygonal frame shape; An area where the gate wiring, the data wiring, and the power wiring cross each other is defined as a pixel region, and is connected to the drain electrode and formed in the pixel region. And a channel that is a region in which pure amorphous silicon material of the semiconductor layer is exposed in a spaced interval between the source electrode and the drain electrode, and includes the driving gate electrode, the driving semiconductor layer, the driving source electrode, and the driving drain. The electrode is an organic light emitting display device, characterized in that the drive comprises a thin film transistor. A gate wiring formed in a first direction; Data and power lines formed in a second direction crossing the first direction and spaced apart from each other; A switching thin film transistor positioned at an intersection point of the gate wiring and the data wiring, the switching thin film transistor comprising a switching gate electrode, a switching semiconductor layer, a switching source electrode, and a switching drain electrode; A driving gate electrode connected to the switching drain electrode; A driving semiconductor layer formed in a region covering the driving gate electrode; A drain electrode formed of any one of a circular or polygonal structure in a central portion of the driving semiconductor layer; An area where the gate line, the data line, and the power line cross each other is defined as a pixel area, and is connected to the drain electrode and formed in the pixel area; It has a structure surrounding the region except for the connection between the drain electrode and the electrode for the organic light emitting diode device, spaced apart from the drain electrode at regular intervals, and has any one of an annular or polygonal frame shape, branched from the power wiring Source electrode connected to the power electrode And a channel which is a region in which pure amorphous silicon material of the semiconductor layer is exposed in a spaced interval between the source electrode and the drain electrode, and includes the driving gate electrode, the driving semiconductor layer, the driving source electrode, and the driving drain. The electrode is an organic light emitting display device, characterized in that the drive comprises a thin film transistor. The method according to any one of claims 6 to 7, The width of the channel is a circumferential length at an intermediate point between the source electrode and the drain electrode, the length of the channel is a value corresponding to the separation distance between the source electrode and the drain electrode. The method according to any one of claims 6 to 7, The organic light emitting diode device includes an organic light emitting diode comprising a first electrode connected to the drain electrode, an organic light emitting layer, and a second electrode. The method according to any one of claims 6 to 7, The driving semiconductor layer is formed of a plurality of divided patterns forming a radial structure, and at a position corresponding to the plurality of semiconductor layers, the channel is composed of a plurality of thin film transistors in parallel to correspond to the channel. The organic light emitting device is connected to form a thin film transistor for driving.

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