Amorphous insulator film and thin-film transistor

• US 8,044,402 B2
• Filed: 02/02/2008
• Issued: 10/25/2011
• Est. Priority Date: 02/19/2007
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kaji, Nobuyuki, Yabuta, Hisato, Hayashi, Ryo
• Primary Examiner(s): Dickey; Thomas L
• Application Number:
  US12/522,371
• Publication Number:
  US 20100051947A1
• Time in Patent Office: 1,361 Days
• Field of Search: 174/137.B, 257/57, 257/66, 257/E29.151, 257/E29.273, 249/43, 249/122, 249/138
• US Class Current: 257/66
• CPC Class Codes: H01L 21/28194 by deposition, e.g. evaporation, ALD, CVD, sputtering, laser deposition H01L21/28202 takes precedence
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/51 Insulating materials associated therewith for MIS structures on thin film semiconductor H01L29/4908
• CPC Class Codes: H01L 29/78609 for preventing leakage current H01L29/78618 takes precedence
• 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

An amorphous insulator film is provided which is composed of silicon (Si) oxide, in which the amorphous insulator film includes Ar and an amount of Ar included therein is equal to or larger than 3 at. % in terms of atomic ratio with respect to Si.

Claims

1. An amorphous insulator film which is used as a gate-insulator film of a thin-film transistor and comprises silicon oxide, wherein

the amorphous insulator film includes Ar;

Ar is included therein in an amount of equal to or larger than 3 at. % and equal to or smaller than 17 at. % in terms of atomic ratio with respect to Si; and

the amorphous insulator film has density which increases with the amount of Ar increases.

2. An amorphous insulator film according to claim 1, wherein the amount of Ar included in the amorphous insulator film is equal to or larger than 5 at. % or equal to or smaller than 16 at. % in terms of atomic ratio with respect to Si.

3. An amorphous insulator film according to claim 1, wherein the amorphous insulator film has a current-voltage characteristic in which a current density when an electric filed of 1 MV/cm is applied to the amorphous insulator film is equal to or smaller than 1×

10<sup>−

6</sup> A/cm².

4. An amorphous insulator film according to claim 1, wherein the amorphous insulator film has a current-voltage characteristic in which a current density when an electric filed of 1 MV/cm is applied to the amorphous insulator film is equal to or smaller than 3×

10<sup>−

7</sup> A/cm².

5. An amorphous insulator film according to claim 1, wherein the amorphous insulator film is produced by a sputtering method.

6. A thin-film transistor wherein the amorphous insulator film according to claim 1 is used as a gate-insulator film.

7. A thin-film transistor according to claim 6, which includes a channel comprising an oxide semiconductor.

8. A thin-film transistor according to claim 6, which includes a channel comprising an amorphous oxide semiconductor.