PIXEL STRUCTURE HAVING HIGH APERTURE RATIO AND CIRCUIT

• US 20160247869A1
• Filed: 09/19/2014
• Published: 08/25/2016
• Est. Priority Date: 09/02/2014
• Status: Active Grant

• Current Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Inventors: LI, Wenhui, LO, Changcheng, TSENG, Chihyuan, HU, Yutong
• Granted Patent: US 9,704,937 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G09G 2300/0465 Improved aperture ratio, e.g. by size reduction of the pixel circuit, e.g. for improving the pixel density or the maximum displayable luminance or brightness
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 29/786 Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785
• CPC Class Codes: H01L 29/78648 arranged on opposing sides of the channel
• CPC Class Codes: H10K 59/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 59/1216 the pixel elements being capacitors
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals

Abstract

The present invention provides a pixel structure having high aperture ratio and circuit. The first gate (21), the first source/the first drain (61), and the etching stopper layer (5), the first semiconductor layer (41), the gate isolation layer (3) sandwiched in-between of the pixel structure having high aperture ratio construct a first thin film transistor (TFT1); the second gate (22), the second source/the second drain (62), and the etching stopper layer (5), the second semiconductor layer (42), the gate isolation layer (3) sandwiched in between construct a second thin film transistor (TFT2); the transparent electrode (8), the pixel electrode (10) and the flat isolation layer (9)sandwiched in-between construct a transparent capacitor (C), and the transparent capacitor (C) constructs an activation area part of the pixel structure which is capable of increasing the activation area of the pixel and raising the aperture ratio to increase the display brightness and reduce the power consumption.

Claims

1. A pixel structure having high aperture ratio, comprising a substrate, a first gate and a second gate, located at one side of the substrate;

a gate isolation layer, located on the first, the second gates and the gate isolation layer, and the gate isolation layer completely covers the first gate and the substrate, and exposes two ends of the second gate;

a first semiconductor layer, located on the gate isolation layer and right over the first gate;

a second semiconductor layer, located on the gate isolation layer and right over the second gate;

an etching stopper layer, located on the first, the second semiconductor layer and the gate isolation layer;

a first source/a first drain, located on the first semiconductor layer and the etching stopper layer;

a second source/a second drain, located on the second semiconductor layer and the etching stopper layer, and the first source/the first drain are connected to the first semiconductor layer and one end of the second gate, and the second source/the second drain are connected to the second semiconductor layer;

a protective layer, located on the first source/the first drain, the second source/the second drain and the etching stopper layer;

a transparent electrode, located on the protective layer and at the other side of the substrate, and the transparent electrode is connected to the other end of the second gate;

a flat isolation layer, located on the protective layer and the transparent electrode;

a pixel electrode, located on the flat isolation layer, and the pixel electrode is connected to the second source/the second drain and overlaps with the transparent electrode;

a pixel definition layer, located on the flat isolation layer and the pixel electrode, and the pixel definition layer comprises an open corresponding to an overlapping district of the pixel electrode and the transparent electrode;

the first gate, the first source/the first drain, and the etching stopper layer, the first semiconductor layer, the gate isolation layer sandwiched in-between construct a first thin film transistor;

the second gate, the second source/the second drain, and the etching stopper layer, the second semiconductor layer, the gate isolation layer sandwiched in between construct a second thin film transistor;

the transparent electrode, the pixel electrode and the flat isolation layer sandwiched in-between construct a transparent capacitor.

2. The pixel structure having high aperture ratio according to claim 1, wherein the transparent capacitor constructs an activation area part of the pixel structure.

3. The pixel structure having high aperture ratio according to claim 1, wherein the transparent electrode is an ITO transparent electrode or an IZO transparent electrode, and the pixel electrode is an ITO pixel electrode or an IZO pixel electrode.

4. The pixel structure having high aperture ratio according to claim 1, further comprising a photoresist spacer located on the pixel definition layer.

5. The pixel structure having high aperture ratio according to claim 1, further comprising a first top gate electrode right over the first gate and between the protective layer and the flat isolation layer, and a second top gate electrode right over the second gate and between the protective layer and the flat isolation layer.

6. The pixel structure having high aperture ratio according to claim 5, wherein the first, the second top gate electrodes and the transparent electrode are formed at the same time.

7. The pixel structure having high aperture ratio according to claim 1, wherein the first semiconductor layer is an IGZO semiconductor layer, and the second semiconductor layer is an IGZO semiconductor layer.

8. A circuit of a pixel structure having high aperture ratio, comprising a first thin film transistor, a second thin film transistor, a transparent capacitor, and a light emitting diode, and both two electrodes constructing the transparent capacitor are transparent electrodes;

a gate of the first thin film transistor is coupled to a gate drive voltage signal, and a source thereof is coupled to a data drive voltage signal, and a drain thereof and a gate of the second thin film transistor are coupled;

a source of the second thin film transistor is coupled to a drive voltage signal, and a drain thereof is coupled to an anode of the organic light emitting diode;

a cathode of the organic light emitting diode is coupled to a ground signal;

one electrode of the transparent capacitor is coupled to the gate of the second thin film transistor, and the other electrode thereof is coupled to the source or the drain of the second thin film transistor.

9. The circuit of the pixel structure having high aperture ratio according to claim 8, further comprising an opaque capacitor, and one electrode of the opaque capacitor is coupled to the gate of the second thin film transistor, and the other electrode thereof is coupled to the source or the drain of the second thin film transistor.

10. The circuit of the pixel structure having high aperture ratio according to claim 9, wherein the source, the drain of the first thin film transistor are switchable, and the source, the drain of the second thin film transistor are switchable, too.

11. A circuit of a pixel structure having high aperture ratio, comprising a first thin film transistor, a second thin film transistor, a transparent capacitor, and a light emitting diode, and both two electrodes constructing the transparent capacitor are transparent electrodes;

a gate of the first thin film transistor is coupled to a gate drive voltage signal, and a source thereof is coupled to a data drive voltage signal, and a drain thereof and a gate of the second thin film transistor are coupled;

a source of the second thin film transistor is coupled to a drive voltage signal, and a drain thereof is coupled to an anode of the organic light emitting diode;

a cathode of the organic light emitting diode is coupled to a ground signal;

one electrode of the transparent capacitor is coupled to the gate of the second thin film transistor, and the other electrode thereof is coupled to the source or the drain of the second thin film transistor;

the circuit of the pixel structure having high aperture ratio further comprises an opaque capacitor, and one electrode of the opaque capacitor is coupled to the gate of the second thin film transistor, and the other electrode thereof is coupled to the source or the drain of the second thin film transistor;

wherein the source, the drain of the first thin film transistor are switchable, and the source, the drain of the second thin film transistor are switchable, too.