THIN FILM TRANSISTOR AND DISPLAY DEVICE

• US 20110180802A1
• Filed: 10/07/2009
• Published: 07/28/2011
• Est. Priority Date: 10/08/2008
• Status: Active Grant

• Current Assignee: JDI Design and Development GK
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Terai, Yasuhiro, Arai, Toshiaki, Morosawa, Narihiro
• Granted Patent: US 8,461,594 B2
• Time in Patent Office: Days
• US Class Current: 257/59
• 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 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels

Abstract

Provided are a thin film transistor that is capable of suppressing desorption of oxygen and others from an oxide semiconductor layer, and reducing the time to be taken for film formation, and a display device provided therewith. A gate insulation film 22, a channel protection layer 24, and a passivation film 26 are each in the laminate configuration including a first layer 31 made of aluminum oxide, and a second layer 32 made of an insulation material including silicon (Si). The first and second layers 31 and 32 are disposed one on the other so that the first layer 31 comes on the side of an oxide semiconductor layer 23. The oxide semiconductor layer 23 is sandwiched on both sides by the first layers 31 made of aluminum oxide, thereby suppressing desorption of oxygen and others, and stabilizing the electrical characteristics of a TFT 20. Moreover, since the second layer 32 is made of an insulation material including silicon (Si), the time to be taken for film formation can be reduced compared with a single layer made of aluminum oxide.

Claims

1-15. -15. (canceled)

16. A thin film transistor comprising:

a gate insulation film between a gate electrode and an oxide semiconductor layer, wherein

on a side of the gate electrode and on a side opposite to the gate electrode of the oxide semiconductor layer, a laminated film including a first layer made of aluminum oxide and a second layer made of an insulation material including silicon (Si) is provided.

17. The thin film transistor according to claim 16, wherein:

the first layer and the second layer are disposed one on the other with the first layer positioned on a side of the oxide semiconductor layer.

18. The thin film transistor according to claim 16, wherein:

a substrate is provided thereon, in order, with the gate electrode, the gate insulation film, the oxide semiconductor layer, a channel protection film, source/drain electrodes, and a passivation film, and

the gate insulation film and one or both of the channel protection film and the passivation film are each the laminated film.

19. The thin film transistor according to claim 17, wherein:

a substrate is provided thereon, in order, with the gate electrode, the gate insulation film, the oxide semiconductor layer, a channel protection film, source/drain electrodes, and a passivation film, and

the gate insulation film and one or both of the channel protection film and the passivation film are each the laminated film.

20. The thin film transistor according to claim 16, wherein:

the second layer includes one or more of a silicon oxide film, a silicon nitride film, and a silicon oxynitride film.

21. A thin film transistor, wherein:

a substrate is provided thereon with, in order, a gate electrode, a gate insulation film, an oxide semiconductor layer, a channel protection film, source/drain electrodes, and a passivation film, and

the passivation film is made of an oxide, nitride, or oxynitride containing one or more of aluminum (Al), titanium (Ti), and tantalum (Ta).

22. The thin film transistor according to claim 21, wherein:

the passivation film is made of aluminum oxynitride or aluminum nitride.

23. The thin film transistor according to claim 21, wherein:

the passivation film has a density of 3.0 g/cm³ or higher but 4.0 g/cm³ or lower.

24. The thin film transistor according to claim 21, wherein:

the passivation film is a single-layer film.

25. The thin film transistor according to claim 22, wherein:

the passivation film is a laminated film.

26. The thin film transistor according to claim 25, wherein:

the laminated film includes a lower layer made of oxide including aluminum (Al), and an upper layer made of oxynitride or nitride including aluminum (Al).

27. The thin film transistor according to claim 21, wherein:

the passivation film is formed by sputtering.

28. A display device comprising:

a thin film transistor; and

a display element, wherein

the thin film transistor includes

a gate insulation film between a gate electrode and an oxide semiconductor layer, and

on a side of the gate electrode and on a side opposite to the gate electrode of the oxide semiconductor layer, a laminated film including a first layer made of aluminum oxide and a second layer made of an insulation material including silicon (Si) is provided.

29. The display device according to claim 28, wherein:

the display element is an organic light-emitting element including, in order from a side of the thin film transistor, an anode, an organic layer including a light-emitting layer, and a cathode.

30. A display device, comprising:

a thin film transistor; and

a display element, wherein

the thin film transistor includes

in order on a substrate, a gate electrode, a gate insulation film, an oxide semiconductor layer, a channel protection film, a source/drain electrode, and a passivation film, and

the passivation film is made of an oxide, nitride, or oxynitride containing one or more of aluminum (Al), titanium (Ti), and tantalum (Ta).

31. The display device according to claim 30, wherein:

the display element is an organic light-emitting element including, in order from a side of the thin film transistor, an anode, an organic layer including a light-emitting layer, and a cathode.