EP-4102565-B1 - DISPLAY DEVICE

Inventors

• MOON, KYEONGJU
• Noh, Soyoung
• SHIN, HYUNSOO
• KIM, WONKYUNG

Dates

Publication Date

20260506

Application Date

20161124

Claims (9)

1. A display device comprising: a substrate (SUB) including a display area (AA) and a non-display area (NA) disposed around the display area; an intermediate insulating layer (ILD) disposed on the substrate (SUB); a second thin film transistor (T2) disposed on the intermediate insulating layer (ILD); a passivation layer (PAS) covering the second thin film transistor (T2); and an organic light emitting diode layer (OLE) disposed on the passivation layer (PAS), wherein the second thin film transistor (T2) includes: an oxide semiconductor layer (SA2, A2, DA2) disposed on the intermediate insulating layer (ILD); a second gate electrode (G2) overlapping a central region of the oxide semiconductor layer (A2); a second gate insulating layer (GI2) disposed between the oxide semiconductor layer (A2) and the second gate electrode (G2); and a second source electrode (S2) and a second drain electrode (D2) disposed on the passivation layer (PAS) and connected to the oxide semiconductor layer (SA2, DA2), wherein the organic light emitting diode (OLE) includes: an anode electrode (ANO) electrically connected to the second thin film transistor (T2); a cathode electrode (CAT) facing the anode electrode (ANO); and an organic light emitting layer (OL) disposed between the anode electrode (ANO) and the cathode electrode (CAT), wherein a color filter (CF) is disposed in a portion corresponding to an area in which the anode electrode (ANO) is disposed, wherein the display device further comprises a first thin film transistor (T1) spaced apart from the second thin film transistor (T2), wherein the first thin film transistor (T1) includes: a polycrystalline semiconductor layer (SA1, A1, DA1) disposed between the substrate (SUB) and the intermediate insulating film (ILD); a first gate insulating layer (GI1) covering the polycrystalline semiconductor layer (SA1, A1, DA1) between the substrate (SUB) and the intermediate insulating film (ILD); a first gate electrode (G1) disposed on the first gate insulating layer (GI1) and covered by the intermediate insulating layer (ILD); and a first source electrode (SA1) and a first drain electrode (DA1) disposed on the intermediate insulating layer (ILD) to be spaced apart from each other, characterised in that the display device further comprises a second light shielding layer (LS2) disposed under the second thin film transistor (T2), wherein the second light shielding layer (LS2) is disposed on the first gate insulating layer (GI1), wherein the intermediate insulating layer (ILD) is disposed on the second light shielding layer (LS2).
2. The display device of claim 1, wherein the second thin film transistor (T2) is a driving thin film transistor (DT) disposed in a pixel of the display area (AA) and driving the pixel.
3. The display device of claim 1, wherein the second gate electrode (G2) is disposed on the oxide semiconductor layer (A2).
4. The display device of claim 1, wherein the second gate insulating layer (GI2) includes a first portion having the same outer shape as the second gate electrode (G2).
5. The display device of claim 1, wherein the second gate insulating layer (GI2) further including: a second portion disposed between the first source electrode (S1) and the intermediate insulating layer (ILD) and having the same outer shape as the first source electrode (S1); and a third portion disposed between the first drain electrode (D1) and the intermediate insulating layer (ILD) and having the same outer shape as the first drain electrode (D1).
6. The display device of claim 5, wherein the first source electrode (S1) is electrically connected to a source region (SA1) of the polycrystalline semiconductor layer through a first source contact hole penetrating a second portion of the second gate insulating layer (GI2), the intermediate insulating layer (ILD), and the first gate insulating layer (GI1), and the first drain electrode (D1) is electrically connected to a drain region (DA1) of the polycrystalline semiconductor layer through a first drain contact hole penetrating a third portion of the second gate insulating layer (GI2), the intermediate insulating layer (ILD), and the first gate insulating layer (GI1).
7. The display device of claim 1, wherein the intermediate insulating layer (ILD) include a nitride layer and an oxide layer stacked on the nitride layer.
8. The display device of claim 1, further comprising: a first storage electrode (ST1) disposed between the first thin film transistor (T1) and the second thin film transistor (T2) on the same layer as the polycrystalline semiconductor layer (SA1, A2, DA1) and covered by the first gate insulating layer (GI1); and a second storage electrode (ST2) disposed on the intermediate insulating layer (ILD) to overlap the first storage electrode (ST1).
9. The display device of claim 1, wherein the cathode electrode (CAT) is connected to a ground line (Vss) at an outermost portion of the substrate (SUB) to receive a ground voltage.

Description

BACKGROUND Field of the Invention The present disclosure relates to a display device including a thin film transistor substrate having two different type thin film transistors on the same substrate. Discussion of the Related Art KR 2015 0101413 A describes a thin film transistor substrate on which different types of thin film transistors are arranged on the same substrate, and a display device using the same. The display device includes a first thin film transistor, a second thin film transistor, a first middle insulating film, a second middle insulating film, and a third middle insulating film. The first thin film transistor includes a polycrystal semiconductor layer, a first gate electrode disposed on the polycrystal semiconductor layer, a first source electrode, and a first drain electrode; and is disposed in a first region. The second thin film transistor includes an oxide semiconductor layer, a second gate electrode disposed on the oxide semiconductor layer, a second source electrode, and a second drain electrode; and is disposed in a second region. The first middle insulating film covers the first gate electrode, is disposed below the oxide semiconductor layer, and includes an oxide film. The second middle insulating film is selectively disposed in the first region except for the second region on the first middle insulating film and includes a nitride film. The third middle insulating film covers the first gate electrode and the second gate electrode on the second middle insulating film and has an oxide film. In an example, an organic light emitting diode is disposed on a passivation layer that covers the second thin film transistor. The organic light emitting diode includes an anode electrode connected to a driving transistor, a cathode electrode facing the anode electrode, and an organic light emitting layer therebetween. A color filter is disposed in a portion corresponding to the area where the anode electrode is disposed. US 2015/0243685 A1 describes a thin film transistor substrate and a display using the same. US 2015/0055051 A1 relates to displays with silicon and semiconducting oxide thin-film transistors. US 2014/0014963 A1 relates to an EL display device in which a switching TFT 201 formed within a pixel has a multi-gate structure. Nowadays, as the information society is developed, the requirements of displays for representing information are increasing. Accordingly, the various flat panel displays (or 'FPD') are developed for overcoming many drawbacks of the cathode ray tube (or 'CRT') such as heavy weight and bulk volume. The flat panel display devices include the liquid crystal display device (or 'LCD'), the plasma display panel (or 'PDP'), the organic light emitting display device (or 'OLED') and the electrophoresis display device (or 'ED'). The display panel of a flat panel display may include a thin film transistor substrate having a thin film transistor allocated in each pixel region arrayed in a matrix manner. For example, the liquid crystal display device (or 'LCD') represents video data by controlling the light transitivity of the liquid crystal layer using the electric fields. For the organic light emitting diode display represents the video data by generating properly controlled light at each pixel disposed in a matrix manner as an organic light emitting diode is formed therein. As a self-emitting display device, the organic light emitting diode display device has the merits those the response speed is very fast, the brightness is very high and the view angle is large. The organic light emitting diode display (or OLED) using the organic light emitting diode having the good energy efficiencies can be categorized in the passive matrix type organic light emitting diode display (or PMOLED) and the active matrix type organic light emitting diode display (or AMOLED). As the personal appliances are more prevailed, portable and/or wearable devices are actively developed. To apply the display device for the portable and/or wearable device, the device has the characteristics of the low power consumption. However, using the technologies having developed until now, it is restricted to get display having the excellent low power consumption properties. SUMMARY Accordingly, the present invention is directed to a display device according to claim 1 that substantially obviate one or more of the problems due to limitations and disadvantages of the related art. An object of the present disclosure is to provide a thin film transistor substrate for flat panel display having at least two transistors of which characteristics are different each other on the same substrate, and a display using the same substrate. Another object of the present disclosure is to provide a non-claimed method for manufacturing a thin film transistor substrate for flat panel display having two different type transistors by the optimized processes and the minimized number of the mask processes, and a thin film transistor subst