Semiconductor film comprising an oxide containing in atoms, Sn atoms and Zn atoms

Patent metadata

Field	Value
Publication number	US-10644163-B2
Application number	US-200913060699-A
Country	US
Kind code	B2
Filing date	Aug 26, 2009
Priority date	Aug 27, 2008
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

A field effect transistor including: a substrate, and at least gate electrode, a gate insulating film, a semiconductor layer, a protective layer for the semiconductor layer, a source electrode and a drain electrode provided on the substrate, wherein the source electrode and the drain electrode are connected with the semiconductor layer therebetween, the gate insulating film is between the gate electrode and the semiconductor layer, the protective layer is on at least one surface of the semiconductor layer, the semiconductor layer includes an oxide containing In atoms, Sn atoms and Zn atoms, the atomic composition ratio of Zn/(In+Sn+Zn) is 25 atom % or more and 75 atom % or less, and the atomic composition ratio of Sn/(In+Sn+Zn) is less than 50 atom %.

First claim

The invention claimed is:

1. An amorphous semiconductor film comprising an oxide containing In atoms, Sn atoms and Zn atoms forming said semiconductor film, which film is amorphous,
the atomic composition ratio of Zn/(In+Sn+Zn) being 57 atom % or more and 66 atom % or less,
the atomic composition ratio of Sn/(In+Sn+Zn) being 10 atom % or more and 18 atom % or less,
the atomic ratio of Sn/Zn being 0.15 or more and 0.27 or less, and an electron carrier concentration of the amorphous semiconductor film is 10 13 to 10 18 /cm 3 , and
wherein the amorphous semiconductor film has an etching speed in PAN of less than 10 nm/min at 40° C. wherein the PAN comprises 87 wt % phosphoric acid, 3 wt % nitric acid and 10 wt % acetic acid.

2. The amorphous semiconductor film according to claim 1 , wherein an average valence number, as measured using X-ray photoelectron spectroscopy (XPS), of Sn is from +3.6 to +4.0.

3. The amorphous semiconductor film according to claim 1 , wherein an average valence number, as measured using X-ray photoelectron spectroscopy (XPS), of Sn is from +3.8 to +4.0.

4. The amorphous semiconductor film according to claim 1 , wherein an average valence number, as measured using X-ray photoelectron spectroscopy (XPS), of Sn is from +3.2 to +4.0.

5. The amorphous semiconductor film according to claim 1 , wherein the atomic ratio of Sn/In is 0.41 or more and 0.69 or less.

Assignees

• Yano Koki
• Kawashima Hirokazu
• Inoue Kazuyoshi
• Idemitsu Kosan Co

Inventors

• Yano Koki
• Kawashima Hirokazu
• Inoue Kazuyoshi

Classifications

• H10P14/3434

  being oxide semiconductor materials (Group IIB-VIA semiconductor materials H10P14/3424) · CPC title

• H10P14/3426

  Oxides · CPC title

• C22C30/04

  containing tin or lead · CPC title

• C23C14/165

  by cathodic sputtering · CPC title

• C22C30/06

  containing zinc · CPC title