AMOLED BACKPLANE STRUCTURE AND MANUFACTURING METHOD THEREOF

• US 20160336385A1
• Filed: 06/18/2015
• Published: 11/17/2016
• Est. Priority Date: 05/13/2015
• 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, Wang, Yifan
• Granted Patent: US 9,614,017 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 27/1248 with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 27/1262 with a particular formation, treatment or coating of the substrate
• CPC Class Codes: H01L 29/45 Ohmic electrodes
• CPC Class Codes: H10K 2102/103 comprising indium oxides, e.g. ITO
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 50/813 characterised by their shape
• CPC Class Codes: H10K 59/1201 Manufacture or treatment
• 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 59/124 Insulating layers formed between TFT elements and OLED elements
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass

Abstract

The present invention provides an AMOLED backplane structure and a manufacturing method thereof. In each sub-pixel, a TFT substrate (TS) includes a corrugation structure (4) formed in an area corresponding to an opening (71) of a pixel definition layer (7). The corrugation structure (4) includes a plurality of raised sections (41) and a recessed section (42) formed between every two adjacent ones of the raised sections (41). An upper surface of a portion of the planarization layer (5) and a portion of a pixel electrode (6) that correspond to and are located above the corrugation structure (4) include curved surfaces corresponding to the corrugation structure (4). The AMOLED backplane structure helps ensure the planarization layer (5) is smooth and free of abrupt change sites and also makes the pixel electrode (6) in a form of a curved surface to increase an effective displaying surface, extend the lifespan of the OLED, reduce difficulty of manufacturing, and improve resolution.

Claims

1. An active matrix organic light emitting display (AMOLED) backplane structure, comprising multiple sub-pixels arranged in an array, wherein in each of the sub-pixels, the AMOLED backplane comprises:

a thin-film transistor (TFT) substrate, a planarization layer formed on the TFT substrate, a pixel electrode formed on the planarization layer, a pixel definition layer formed on the pixel electrode, and a photo spacer formed on the pixel definition layer;

the TFT substrate comprises therein a switch TFT, a drive TFT, and a capacitor;

the pixel definition layer comprises an opening to expose a portion of the pixel electrode

the TFT substrate comprises a corrugation structure arranged in an area corresponding to the opening of the pixel definition layer, the corrugation structure comprising a plurality of raised sections and a recessed section formed between every two adjacent ones of the raised sections, the raised sections and the recessed sections having vertical dimensions identical to each other; and

an upper surface of a portion of the planarization layer and a portion of the pixel electrode that correspond to and are located above the corrugation structure have curved configurations corresponding to the corrugation structure.

2. The AMOLED backplane structure as claimed in claim 1, wherein in each of the sub-pixels, the TFT substrate comprises a base plate, first and second gate terminals formed on the base plate and spaced from each other, a gate insulation layer formed on the first and second gate terminals and the base plate, first and second semiconductor layers formed on the gate insulation layer and respectively located on the first and second gate terminals, an etch stop layer formed on the first and second semiconductor layers and the gate insulation layer, a first source terminal formed on the etch stop layer and in contact engagement with the first semiconductor layer, a first drain terminal formed on the etch stop layer and in contact engagement with the first semiconductor layer and the second gate terminal, a second source terminal formed on the etch stop layer and in contact engagement with the second semiconductor layer, a second drain terminal formed on the etch stop layer and in contact engagement with the second semiconductor layer, and a protective layer formed on the etch stop layer, the first source and drain terminals, and the second source and drain terminals;

the first gate terminal, the first semiconductor layer, the first source terminal, and the first drain terminal constituting the switch TFT, the second gate terminal, the second semiconductor layer, the second source terminal, and the second drain terminal constituting the drive TFT, the second gate terminal and the second source terminal also constituting the capacitor, the pixel electrode being in contact engagement with the second drain terminal.

3. The AMOLED backplane structure as claimed in claim 2, wherein the corrugation structure is formed in the protective layer of the TFT substrate.

4. The AMOLED backplane structure as claimed in claim 2, wherein the corrugation structure is formed in the protective layer and the etch stop layer of the TFT substrate.

5. The AMOLED backplane structure as claimed in claim 2, wherein in each of the sub-pixels, the TFT substrate further comprises a metal layer formed between the protective layer and the etch stop layer in the area corresponding to the opening of the pixel definition layer and the metal layer is formed simultaneously with the first source and drain terminals and the second source and drain terminals;

the corrugation structure being formed on the metal layer.

6. The AMOLED backplane structure as claimed in claim 2, wherein the protective layer and the etch stop layer comprise a material of silicon nitride, silicon oxide, or a combination thereof;

and the first and second gate terminals, the first source and drain terminals and the second source and drain terminals comprise a material of one of molybdenum, titanium, aluminum, and copper, or a combination thereof.

7. The AMOLED backplane structure as claimed in claim 2, wherein the pixel electrode comprises a material of indium tin oxide (ITO).

8. The AMOLED backplane structure as claimed in claim 1, wherein the corrugation structure is formed in a portion of or all the sub-pixels.

9. An active matrix organic light emitting display (AMOLED) backplane structure, comprising multiple sub-pixels arranged in an array, wherein in each of the sub-pixels, the AMOLED backplane comprises:

a thin-film transistor (TFT) substrate, a planarization layer formed on the TFT substrate, a pixel electrode formed on the planarization layer, a pixel definition layer formed on the pixel electrode, and a photo spacer formed on the pixel definition layer;

the TFT substrate comprises therein a switch TFT, a drive TFT, and a capacitor;

the pixel definition layer comprises an opening to expose a portion of the pixel electrode;

the TFT substrate comprises a corrugation structure arranged in an area corresponding to the opening of the pixel definition layer, the corrugation structure comprising a plurality of raised sections and a recessed section formed between every two adjacent ones of the raised sections, the raised sections and the recessed sections having vertical dimensions identical to each other; and

an upper surface of a portion of the planarization layer and a portion of the pixel electrode that correspond to and are located above the corrugation structure have curved configurations corresponding to the corrugation structure;

wherein in each of the sub-pixels, the TFT substrate comprises a base plate, first and second gate terminals formed on the base plate and spaced from each other, a gate insulation layer formed on the first and second gate terminals and the base plate, first and second semiconductor layers formed on the gate insulation layer and respectively located on the first and second gate terminals, an etch stop layer formed on the first and second semiconductor layers and the gate insulation layer, a first source terminal formed on the etch stop layer and in contact engagement with the first semiconductor layer, a first drain terminal formed on the etch stop layer and in contact engagement with the first semiconductor layer and the second gate terminal, a second source terminal formed on the etch stop layer and in contact engagement with the second semiconductor layer, a second drain terminal formed on the etch stop layer and in contact engagement with the second semiconductor layer, and a protective layer formed on the etch stop layer, the first source and drain terminals, and the second source and drain terminals;

the first gate terminal, the first semiconductor layer, the first source terminal, and the first drain terminal constituting the switch TFT, the second gate terminal, the second semiconductor layer, the second source terminal, and the second drain terminal constituting the drive TFT, the second gate terminal and the second source terminal also constituting the capacitor, the pixel electrode being in contact engagement with the second drain terminal;

wherein the corrugation structure is formed in a portion of or all the sub-pixels; and

wherein the pixel electrode comprises a material of indium tin oxide (ITO).

10. The AMOLED backplane structure as claimed in claim 9, wherein the corrugation structure is formed in the protective layer of the TFT substrate.

11. The AMOLED backplane structure as claimed in claim 9, wherein the corrugation structure is formed in the protective layer and the etch stop layer of the TFT substrate.

12. The AMOLED backplane structure as claimed in claim 9, wherein in each of the sub-pixels, the TFT substrate further comprises a metal layer formed between the protective layer and the etch stop layer in the area corresponding to the opening of the pixel definition layer and the metal layer is formed simultaneously with the first source and drain terminals and the second source and drain terminals;

the corrugation structure being formed on the metal layer.

13. The AMOLED backplane structure as claimed in claim 9, wherein the protective layer and the etch stop layer comprise a material of silicon nitride, silicon oxide, or a combination thereof;

and the first and second gate terminals, the first source and drain terminals and the second source and drain terminals comprise a material of one of molybdenum, titanium, aluminum, and copper, or a combination thereof.

14. A manufacturing method of an active matrix organic light emitting display (AMOLED) backplane, comprising the following steps:

(1) manufacturing a thin-film transistor (TFT) substrate and forming a corrugation structure during the manufacturing of the TFT substrate, wherein the corrugation structure comprises a plurality of raised sections and a recessed section between every two adjacent ones of the raised sections;

(2) coating organic photoresist on the TFT substrate that comprises the corrugation structure formed thereon to form a planarization layer in such a way that an upper surface of a portion of the planarization layer corresponding to and located above the corrugation structure comprises a curved configuration corresponding to the corrugation structure;

(3) forming a pixel electrode on the planarization layer in such a way that the pixel electrode shows a curved configuration; and

(4) forming, in sequence, a pixel definition layer and a photo spacer on the pixel electrode and the planarization layer;

the pixel definition layer comprising an opening to expose the curved configuration of the pixel electrode.

15. The manufacturing method of the AMOLED backplane as claimed in claim 14, wherein the corrugation structure is formed through an etching process.