Transparent OLED display with transparent storage capacitor and manufacturing method thereof

• US 10,446,633 B2
• Filed: 11/29/2017
• Issued: 10/15/2019
• Est. Priority Date: 10/24/2017
• Status: Active Grant

• Current Assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd.
• Original Assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd.
• Inventors: Liu, Zhaosong, Im, Jangsoon
• Primary Examiner(s): Hoang, Quoc D
• Application Number:
  US15/742,746
• Publication Number:
  US 20190123121A1
• Time in Patent Office: 685 Days
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/0274 Photolithographic processes
• CPC Class Codes: H01L 21/441 Deposition of conductive or insulating materials for electrodes
• 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 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 27/1259 Multistep manufacturing methods
• CPC Class Codes: H01L 27/1262 with a particular formation, treatment or coating of the substrate
• CPC Class Codes: H01L 27/127 with a particular formation, treatment or patterning of the active layer specially adapted to the circuit arrangement
• CPC Class Codes: H01L 28/60 Electrodes
• CPC Class Codes: H01L 29/24 including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22 including organic materials H10K99/00
• CPC Class Codes: H01L 29/42364 characterised by the insulating layer, e.g. thickness or uniformity H01L29/42324 and H01L29/4234 take precedence
• CPC Class Codes: H01L 29/42372 characterised by the conducting layer, e.g. the length, the sectional shape or the lay-out H01L29/42324 takes precedence
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/45 Ohmic electrodes
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
• CPC Class Codes: H10K 2102/00 : Constructional details relating to the organic devices covered by this subclass
• CPC Class Codes: H10K 2102/103 : comprising indium oxides, e.g. ITO
• CPC Class Codes: H10K 2102/351 : Thickness
• CPC Class Codes: H10K 50/81 : Anodes
• CPC Class Codes: H10K 50/816 : Multilayers, e.g. transparent multilayers
• CPC Class Codes: H10K 59/1201 : Manufacture or treatment
• CPC Class Codes: H10K 59/121 : characterised by the geometry or disposition of pixel elements
• 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
• CPC Class Codes: H10K 71/00 : Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: H10K 71/60 : Forming conductive regions or layers, e.g. electrodes

Abstract

The present disclosure provides a transparent OLED display and a manufacturing method thereof. The manufacturing method of the transparent OLED display forms an active layer and a first storage capacitor electrode in the same process. The first storage capacitor electrode is made of the transparent metal oxide semiconductor material. A second storage capacitor electrode is manufactured by two photolithography processes so the second storage capacitor electrode is made of only a transparent conductive oxide material. A storage capacitor region where the first storage capacitor electrode and the second storage capacitor electrode are located is a transparent region. Thus, light transmittance and transparent display effect of the transparent OLED display is enhanced. Further, a terminal located in a peripheral region is formed and only made of the transparent conductive oxide material to prevent it from being corroded by water and oxygen. It enhances service life of the transparent OLED display.

Claims

1. A method of manufacturing a transparent organic light-emitting diode (OLED) display, comprising steps of:

adopting a transparent metal oxide semiconductor material to manufacture a first storage capacitor electrode;

adopting a transparent conductive oxide material to manufacture a second storage capacitor electrode; and

forming a terminal comprising a second transparent conductive oxide layer in a peripheral region located on a periphery of a display region;

wherein the second storage capacitor electrode and the first storage capacitor electrode together form a storage capacitor;

the method further comprising steps of;

step S1;

providing a base substrate, forming a gate on the base substrate, and forming a gate insulating layer on the base substrate and covering the gate;

step S2;

forming an active layer corresponding to a top of the gate and the first storage capacitor electrode on the gate insulating layer at intervals, wherein the active layer and the first storage capacitor electrode are both made of a transparent metal oxide semiconductor material;

step S3;

forming an etching stop layer covering the active layer and the first storage capacitor electrode on the gate insulating layer, wherein the etching stop layer comprises a first through hole and a second through hole corresponding to two ends of the active layer;

step S4;

forming a source and a drain on the etching stop layer, wherein the source and the drain contact the two ends of the active layer via the first through hole and the second through hole;

step S5;

forming a passivation layer covering the source and the drain on the etching stop layer, wherein the passivation layer comprises a third through hole corresponding to a top of the first storage capacitor electrode and a first via hole corresponding to a top of the drain, and forming a flat layer on the passivation layer, wherein the flat layer comprises a second via hole corresponding to a top of the first via hole, the first via hole and the second via hole together form a fourth through hole, and the flat layer comprises a fifth through hole formed in a region of the third through hole;

step S6;

depositing a first transparent conductive oxide layer and an anode metal layer on the flat layer from bottom to top, wherein the first transparent conductive oxide layer and the anode metal layer are patterned to form an anode preset pattern, and depositing the second transparent conductive oxide layer on the anode preset pattern, the flat layer, and the etching stop layer, wherein the second transparent conductive oxide layer is patterned to form an anode corresponding to the anode preset pattern on the flat layer and the second storage capacitor electrode located on the etching stop layer located on a bottom of the fifth through hole, the anode comprises the first transparent conductive oxide layer, the anode metal layer, the second transparent conductive oxide layer sequentially laminated on the flat layer from bottom to top, the second storage capacitor electrode comprises the second transparent conductive oxide layer on the etching stop layer, the anode contacts the drain via the fourth through hole, and the second storage capacitor electrode and the first storage capacitor electrode together form a storage capacitor; and

step S7;

forming a pixel defining layer on the anode, the second storage capacitor electrode, and the flat layer, wherein the pixel defining layer comprises an opening corresponding to a top of the anode, forming an OLED light-emitting layer on the anode located inside the opening, and forming a cathode covering the OLED light-emitting layer on the OLED light-emitting layer and the pixel defining layer.

2. The method according to claim 1, wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer are made of a transparent conductive oxide material, the transparent conductive oxide material comprises indium tin oxide (ITO), a material of the anode metal layer comprises Ag, thicknesses of the first transparent conductive oxide layer or the second transparent conductive oxide layer are both 500 Å

-1000 Å

, and a thickness of the anode metal layer is 1000 Å

-3000 Å

.

3. The method according to claim 1, wherein a method of manufacturing the active layer and the first storage capacitor electrode comprises steps of:

depositing the transparent metal oxide semiconductor material on the gate insulating layer; and

patterning the transparent metal oxide semiconductor material to form the active layer and the first storage capacitor electrode by photolithography,

wherein the transparent metal oxide semiconductor material comprises a material selected from a group consisting of indium gallium zinc oxide (IGZO), indium zinc tin oxide (IZTO), and indium gallium zinc tin oxide (IGZTO), and thicknesses of the active layer and the first storage capacitor electrode are both 100 Å

-1000 Å

.

4. A transparent OLED display, comprising:

a first storage capacitor electrode manufactured by a transparent metal oxide semiconductor material;

a second storage capacitor electrode manufactured by a transparent conductive oxide material; and

a terminal comprising a second transparent conductive oxide layer formed in a peripheral region located on a periphery of a display region;

wherein the second storage capacitor electrode and the first storage capacitor electrode together form a storage capacitor;

the transparent OLED display further comprising;

a base substrate;

a gate disposed on the base substrate;

a gate insulating layer on the base substrate and covering the gate;

an active layer disposed on the gate insulating layer and corresponding to the top of the gate;

the first storage capacitor electrode disposed on the gate insulating layer and with the active layer at intervals;

an etching stop layer disposed on the gate insulating layer and covering the active layer and the first storage capacitor electrode;

a source and a drain disposed on the etching stop layer;

a passivation layer disposed on the etching stop layer and covering the source and the drain;

a flat layer disposed on the passivation layer;

an anode disposed on the flat layer;

the second storage capacitor electrode disposed on the etching stop layer and corresponding to a top of the first storage capacitor electrode;

a pixel defining layer disposed on the anode, the second storage capacitor electrode, and the flat layer;

an opening disposed on the pixel defining layer and corresponding to a top of the anode;

an OLED light-emitting layer disposed in the opening and located on the anode; and

a cathode disposed on the OLED light-emitting layer and the pixel defining layer and covering the OLED light-emitting layer;

wherein the etching stop layer comprises a first through hole and a second through hole corresponding to two ends of the active layer, the passivation layer comprises a third through hole corresponding to a top of the first storage capacitor electrode, the flat layer and the passivation layer comprise a fourth through hole corresponding to a top of the drain, and the flat layer comprises a fifth through hole in the region of the third through hole;

wherein the source and the drain respectively contact the two ends of the active layer via the first through hole and the second through hole, the anode contacts the drain via the fourth through hole, the second storage capacitor electrode is disposed on the etching stop layer located on the bottom of the fifth through hole, and the second storage capacitor electrode and the first storage capacitor electrode together form the storage capacitor;

wherein the active layer and the first storage capacitor electrode are both made of the transparent metal oxide semiconductor material, the anode comprises a first transparent conductive oxide layer, an anode metal layer, and the second transparent conductive oxide layer sequentially laminated on the flat layer from bottom to top, and the second storage capacitor electrode comprises a second transparent conductive oxide layer disposed on the etching stop layer.

5. The transparent OLED display according to claim 4, wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer are made of a transparent conductive oxide material, the transparent conductive oxide material comprises ITO, a material of the anode metal layer comprises Ag, thicknesses of the first transparent conductive oxide layer or the second transparent conductive oxide layer are both 500 Å

-1000 Å

, and a thickness of the anode metal layer is 1000 Å

-3000 Å

.

6. The transparent OLED display according to claim 4, wherein the transparent metal oxide semiconductor material comprises a material selected from a group consisting of IGZO, IZTO, and IGZTO, and thicknesses of the active layer and the first storage capacitor electrode are both 100 Å

-1000 Å

.

7. A method of manufacturing a transparent OLED display, comprising steps of:

adopting a transparent metal oxide semiconductor material to manufacture a first storage capacitor electrode; and

adopting a transparent conductive oxide material to manufacture a second storage capacitor electrode;

wherein the second storage capacitor electrode and the first storage capacitor electrode together form a storage capacitor, further comprising steps of;

step S1;

providing a base substrate, forming a gate on the base substrate, and forming a gate insulating layer on the base substrate and covering the gate;

step S2;

forming an active layer corresponding to a top of the gate and the first storage capacitor electrode on the gate insulating layer at intervals, wherein the active layer and the first storage capacitor electrode are both made of a transparent metal oxide semiconductor material;

step S3;

forming an etching stop layer covering the active layer and the first storage capacitor electrode on the gate insulating layer, wherein the etching stop layer comprises a first through hole and a second through hole corresponding to two ends of the active layer;

step S4;

forming a source and a drain on the etching stop layer, wherein the source and the drain contact the two ends of the active layer via the first through hole and the second through hole;

step S5;

forming a passivation layer covering the source and the drain on the etching stop layer, wherein passivation layer comprises a third through hole corresponding to a top of the first storage capacitor electrode and a first via hole corresponding to a top of the drain, and forming a flat layer on the passivation layer, wherein the flat layer comprises a second via hole corresponding to a top of the first via hole, the first via hole and the second via hole together form a fourth through hole, and the flat layer comprises a fifth through hole formed in a region of the third through hole;

step S6;

depositing a first transparent conductive oxide layer and an anode metal layer on the flat layer from bottom to top, wherein the first transparent conductive oxide layer and the anode metal layer are patterned to form an anode preset pattern, and depositing a second transparent conductive oxide layer on the anode preset pattern, the flat layer, and the etching stop layer, wherein the second transparent conductive oxide layer is patterned to form an anode corresponding to the anode preset pattern on the flat layer and the second storage capacitor electrode located on the etching stop layer located on a bottom of the fifth through hole, the anode comprises the first transparent conductive oxide layer, the anode metal layer, the second transparent conductive oxide layer sequentially laminated on the flat layer from bottom to top, the second storage capacitor electrode comprises the second transparent conductive oxide layer on the etching stop layer, the anode contacts the drain via the fourth through hole, and the second storage capacitor electrode and the first storage capacitor electrode together form a storage capacitor;

step S7;

forming a pixel defining layer on the anode, the second storage capacitor electrode, and the flat layer, wherein the pixel defining layer comprises an opening corresponding to a top of the anode, forming an OLED light-emitting layer on the anode located inside the opening, and forming a cathode covering the OLED light-emitting layer on the OLED light-emitting layer and the pixel defining layer;

wherein the base substrate comprises a display region and a peripheral region located on a periphery of the display region, and in the step S6, after patterning the second transparent conductive oxide layer to form the anode and the second storage capacitor electrode, a terminal is formed on the flat layer and in the peripheral region and comprises the second transparent conductive oxide layer disposed on the flat layer;

wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer are made of a transparent conductive oxide material, the transparent conductive oxide material comprises ITO, a material of the anode metal layer comprises Ag, thicknesses of the first transparent conductive oxide layer or the second transparent conductive oxide layer are both 500 Å

-1000 Å

, and a thickness of the anode metal layer is 1000 Å

-3000 Å

;

wherein a method of manufacturing the active layer and the first storage capacitor electrode comprises steps of;

depositing the transparent metal oxide semiconductor material on the gate insulating layer; and

patterning the transparent metal oxide semiconductor material to form the active layer and the first storage capacitor electrode by photolithography,

wherein the transparent metal oxide semiconductor material comprises a material selected from a group consisting of IGZO, IZTO, and IGZTO, and thicknesses of the active layer and the first storage capacitor electrode are both 100 Å

-1000 Å

.