Oxide semiconductor thin-film and thin-film transistor consisted thereof

Patent metadata

Field	Value
Publication number	US-11677031-B2
Application number	US-201916529833-A
Country	US
Kind code	B2
Filing date	Aug 2, 2019
Priority date	Apr 10, 2017
Publication date	Jun 13, 2023
Grant date	Jun 13, 2023

Abstract

The present application discloses an oxide semiconductor thin-film and a thin-film transistor consisted thereof. The oxide semiconductor thin-film is fabricated by doping a certain amount of rare-earth oxide (RO) as light stabilizer to metal oxide (MO) semiconductor. The thin-film transistor comprising a gate electrode, a channel layer consisted by the oxide semiconductor thin-film, a source and drain electrode; the thin-film transistor employing etch-stop structure, a back-channel etch structure or a top-gate self-alignment structure.

First claim

What is claimed is:

1. An oxide semiconductor thin-film, wherein, the oxide semiconductor thin-film is fabricated from a (MO) x (RO) y semiconductor material by doping an amount of rare-earth oxide (RO) as a light stabilizer to a metal oxide (MO) semiconductor, wherein, 0.8≤x<1, 0.012≤y≤0.2, x+y=1;
the M in the metal oxide semiconductor consists of one or more elements selected from the group consisting of In, Zn, Ga, Sn, and combinations thereof;
the R in the rare-earth oxide is at least one element selected from the group consisting of Pr, Tb, Dy, and Yb.

2. The oxide semiconductor thin-film of claim 1 , wherein, the M in the metal oxide semiconductor is a combination of Zn with one or two elements selected from Sn, In and Ga.

3. The oxide semiconductor thin-film of claim 2 , wherein, the metal oxide semiconductor is one selected from the group consisting of indium-zinc-oxide, indium-gallium-zinc-oxide, indium-tin-zinc-oxide and tin-zinc-oxide.

4. The oxide semiconductor thin-film of claim 3 , wherein, ingredient mole ratio of In 2 O 3 :ZnO is 2:1 in the indium-zinc-oxide.

5. The oxide semiconductor thin-film of claim 3 , wherein, ingredient mole ratio of In 2 O 3 :Ga 2 O 3 :ZnO is 2:1:2 in the indium-gallium-zinc-oxide.

6. The oxide semiconductor thin-film of claim 3 , wherein, ingredient mole ratio of In 2 O 3 :SnO 2 :ZnO is 1:1:1 in the indium-tin-zinc-oxide.

7. The oxide semiconductor thin-film of claim 3 , wherein, ingredient mole ratio of ZnO:SnO 2 is 2:1 in the tin-zinc-oxide.

8. The oxide semiconductor thin-film of claim 1 , wherein, the (MO) x (RO) y semiconductor material is one selected from the group consisting of praseodymium-doped indium-zinc-oxide, terbium-doped indium-gallium-zinc-oxide, dysprosium-doped indium-tin-zinc-oxide, and ytterbium-doped tin-zinc-oxide.

9. The oxide semiconductor thin-film of claim 1 , wherein, the oxide semiconductor thin-film is fabricated by sputtering in Ar and O 2 mixture gas with an oxygen volume ratio at 0.1 to 0.6.

10. The oxide semiconductor thin-film of claim 1 , wherein, the oxide semiconductor thin-film is fabricated by sputtering in Ar and O 2 mixture gas with an oxygen volume ratio at 0.2 to 0.3.

11. The oxide semiconductor thin-film of claim 1 , wherein, the oxide semiconductor thin-film is fabricated by a solution process.

12. A thin-film transistor, comprising a channel layer consisted by an oxide semiconductor thin-film, wherein,
the oxide semiconductor thin-film is fabricated from a (MO) x (RO) y semiconductor material by doping an amount of rare-earth oxide (RO) as a light stabilizer to a metal oxide (MO) semiconductor, wherein, 0.8≤x<1, 0.012≤y≤0.2, x+y=1;
the M in the metal oxide semiconductor consists of one or more elements selected from In, Zn, Ga, Sn, and combinations thereof;
the R in the rare-earth oxide is at least one element selected from the group consisting of Pr, Tb, Dy, and Yb.

13. The thin-film transistor of claim 12 , further comprising: a substrate, a gate electrode, a gate insulator layer, an etch-stop layer, a source and drain electrode; wherein, the thin-film transistor employs an etch-stop structure.

14. The thin-film transistor of claim 12 , further comprising: a substrate, a gate electrode, a gate insulator layer, a source and drain electrode; wherein, the thin-film transistor employs a back-channel etch structure.

15. The thin-film transistor of claim 14 , wherein, the source and drain electrode is patterned under etchant of hydrogen peroxide based etching solution or aluminic based etching solution.

16. The thin-film transistor of claim 12 , further comprising: a substrate, a buffer layer, a gate insulator layer, a gate electrode, an interval layer, a source and drain electrode; wherein, the thin-film transistor employs a top-gate self-alignment structure.

17. The thin-film transistor of claim 16 , wherein, the substrate is a flexible substrate made from polyimide, polyethylene naphthalate, polyethylene terephthalate, polyethylene, polypropylene, polystyrene, or polyethersulfone.

18. The oxide semiconductor thin-film of claim 1 , having an indirect band-gap.

19. The thin-film transistor of claim 12 , wherein the oxide semiconductor thin-film has an indirect band-gap.

Assignees

• Univ South China Tech

Inventors

• Xu Miao
• Xu Hua
• Wu Weijing
• Chen Weifeng
• Wang Lei
• Peng Junbiao

Classifications

• H10P50/642

  Chemical etching · CPC title

• H10P14/6329

  using physical ablation of a target, e.g. physical vapour deposition or pulsed laser deposition · CPC title

• H10P14/3446

  Transition metal elements; Rare earth elements · CPC title

• H10P14/22

  using physical deposition, e.g. vacuum deposition or sputtering · CPC title

• H10P14/3426

  Oxides · CPC title