Field effect transistor using amorphous oxide film as channel layer, manufacturing method of field effect transistor using amorphous oxide film as channel layer, and manufacturing method of amorphous oxide film

• US 8,154,024 B2
• Filed: 04/19/2011
• Issued: 04/10/2012
• Est. Priority Date: 09/06/2005
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Iwasaki, Tatsuya
• Primary Examiner(s): Nguyen, Dao H
• Application Number:
  US13/089,703
• Publication Number:
  US 20110193082A1
• Time in Patent Office: 357 Days
• Field of Search: 257/52, 257/55, 257/57, 257/72, 257/79, 257/98, 257/E21.46, 257/E21.441, 257/E21.461, 257/E29.145, 257/E29.273, 257/E29.299, 438/104, 438/151
• US Class Current: 257/72
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/78693 the semiconducting oxide being amorphous

Abstract

An amorphous oxide containing hydrogen (or deuterium) is applied to a channel layer of a transistor. Accordingly, a thin film transistor having superior TFT properties can be realized, the superior TFT properties including a small hysteresis, normally OFF operation, a high ON/OFF ratio, a high saturated current, and the like. Furthermore, as a method for manufacturing a channel layer made of an amorphous oxide, film formation is performed in an atmosphere containing a hydrogen gas and an oxygen gas, so that the carrier concentration of the amorphous oxide can be controlled.

Claims

1. A field effect transistor having a channel layer of an amorphous oxide film comprising at least one material selected from a Ga—

In—

Zn oxide, a Sn—

In—

Zn oxide, an In—

Zn—

Ga —

Mg oxide, an In-Sn oxide, an In—

Ga oxide, and an In—

Zn oxide,

wherein the amorphous oxide film shows an electron carrier concentration in the range of 10¹⁴ to 10¹⁸/cm³, and

wherein the amorphous oxide film contains hydrogen atoms at a concentration in the range of 10¹⁶ to 10²⁰/cm³.

2. The field effect transistor according to claim 1, wherein the concentration of hydrogen atoms contained in the amorphous oxide film is in the range of 10¹⁷ to 10¹⁹/cm³.

3. The field effect transistor according to claim 1, wherein the amorphous oxide film contains In and Zn, and

wherein the number of In atoms in the amorphous oxide film is in the range of 20 to 70 atomic percent of the total number of atoms except oxygen atoms.

4. The field effect transistor according to claim 1, wherein the amorphous oxide film contains In and Sn, and

wherein the number of In atoms in the amorphous oxide film is in the range of 20 to 80 atomic percent of the total number of atoms except oxygen atoms.

5. The field effect transistor according to claim 1, wherein the amorphous oxide film contains Ga, In and Zn.