Amorphous oxide semiconductor and thin film transistor using the same

• US 8,129,718 B2
• Filed: 08/03/2009
• Issued: 03/06/2012
• Est. Priority Date: 08/28/2008
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hayashi, Ryo, Omura, Hideyuki, Kumomi, Hideya, Shigesato, Yuzo
• Primary Examiner(s): STARK, JARRETT J
• Application Number:
  US12/534,436
• Publication Number:
  US 20100051938A1
• Time in Patent Office: 946 Days
• Field of Search: 257/43, 257/E29.296
• US Class Current: 257/43
• CPC Class Codes: H01L 29/78663 Amorphous silicon transistors
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

There is provided an amorphous oxide semiconductor including hydrogen and at least one element of indium (In) and zinc (Zn), the amorphous oxide semiconductor containing one of hydrogen atoms and deuterium atoms of 1×10²⁰ cm⁻³ or more to 1×10²² cm⁻³ or less, and a density of bonds between oxygen and hydrogen except bonds between excess oxygen (O_EX) and hydrogen in the amorphous oxide semiconductor being 1×10¹⁸ cm⁻³ or less.

Claims

1. An amorphous oxide semiconductor containing hydrogen and at least one element of indium (In) and zinc (Zn), wherein:

the amorphous oxide semiconductor contains one of hydrogen atoms and deuterium atoms, whose content is more than 1×

10 ²⁰ cm <sup>−

3</sup> to 1×

10²² cm⁻

or less; and

a density of bonds between oxygen and hydrogen except bonds between excess oxygen (O_Ex) and hydrogen in the amorphous oxide semiconductor is 1×

10¹⁸ cm<sup>−

3</sup> or less.

2. A thin film transistor comprising a channel layer, a gate insulating layer, a source electrode, a drain electrode, and a gate electrode,

wherein the channel layer comprises the amorphous oxide semiconductor according to claim 1.

3. The thin film transistor according to claim 2, wherein an electrical resistivity of the amorphous oxide semiconductor is more than 10Ω

and less than 1×

10⁶Ω

.

4. The thin film transistor according to claim 2, wherein the amorphous oxide semiconductor further comprises at least one of gallium (Ga) and tin (Sn).

5. A display apparatus comprising a display device and a thin film transistor,

the display device including an electrode connected to one of a source electrode and a drain electrode of the thin film transistor on a substrate,

wherein the thin film transistor comprises a thin film transistor according to claim 2.

6. The display apparatus according to claim 5, wherein the display device comprises an electroluminescent device.

7. The display apparatus according to claim 5, wherein the display device comprises a liquid crystal cell.

8. The display apparatus according to claim 5, wherein a plurality of the display devices and a plurality of the thin film transistors are disposed two-dimensionally on the substrate.

9. The thin film transistor according to claim 2, wherein the amorphous oxide semiconductor includes excess oxygen and hydrogen, and a ratio of number of the excess oxygen atoms to number of the hydrogen atoms is 1:

2 or more.