FIELD EFFECT TRANSISTOR AND PROCESS FOR PRODUCTION THEREOF

• US 20100084655A1
• Filed: 10/05/2009
• Published: 04/08/2010
• Est. Priority Date: 10/08/2008
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Iwasaki, Tatsuya, Itagaki, Naho
• Granted Patent: US 8,164,090 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: H01L 29/78618 characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• 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

A field effect transistor has a gate electrode, gate-insulating layer, a channel and a source and drain electrodes connected electrically to the channel, the channel comprising an oxide semiconductor, the source electrode or the drain electrode comprising an oxynitride.

Claims

1. A field effect transistor having a gate electrode, gate-insulating layer, a channel and a source and drain electrodes connected electrically to the channel,

the channel comprising an oxide semiconductor,

the source electrode or the drain electrode comprising an oxynitride.

2. The field effect transistor according to claim 1, wherein a main metallic element of the oxynitride is zinc (Zn) or indium (In).

3. The field effect transistor according to claim 1, wherein the main metallic element contained in the oxide semiconductor and the main metallic element contained in the oxynitride are the same.

4. The field effect transistor according to claim 3, wherein the oxide semiconductor contains zinc (Zn), indium (In), and oxygen (O), and has an amorphous structure, and

the oxynitride contains a crystal which contains zinc (Zn), indium (In), oxygen (O), and nitrogen (N).

5. The field effect transistor according to claim 1, wherein the compositional ratio of oxygen and nitrogen contained in the oxynitride is represented by the relational expression (1);

(Nitrogen atoms)/(Nitrogen atoms+Oxygen atoms)≧

0.01 

 

(1)

6. The field effect transistor according to claim 1, wherein an optical band gap of the oxynitride is smaller than an optical band gap of the oxide semiconductor.

7. The field effect transistor according to claim 1, wherein the source electrode and the drain electrode are a source region and a drain region formed by addition of nitrogen to the oxide semiconductor constituting the channel.

8. A process for producing a field effect transistor, comprising the steps of:

forming an oxide semiconductor film on a substrate,

adding nitrogen to parts of the oxide semiconductor film to form source and drain regions comprised of an oxynitride, and

leaving the non-nitrogen-added portion as a channel region.

9. The process for producing a field effect transistor according to claim 8, comprising the steps of:

forming a gate electrode, and

forming a source region and a drain region by addition of nitrogen, by use of the gate electrode as a mask, to unmasked regions of the oxide semiconductor film by self-aligning relative to the gate electrode.