FIELD EFFECT TRANSISTOR, SEMICONDUCTOR DEVICE AND SEMICONDUCTOR DEVICE MANUFACTURING METHOD

• US 20110049511A1
• Filed: 01/16/2009
• Published: 03/03/2011
• Est. Priority Date: 01/17/2008
• Status: Active Grant

• Current Assignee: Idemitsu Kosan Company Limited
• Original Assignee: Idemitsu Kosan Company Limited
• Inventors: Inoue, Kazuyoshi, Yano, Koki, Tomai, Shigekazu
• Granted Patent: US 8,704,217 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• 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 including a source electrode 107a, a drain electrode 107b, a gate electrode 103, an insulating film 105 and a semiconductor layer 109 containing a crystalline oxide, wherein the source electrode 107a and the drain electrode 107b are self-aligned with the gate electrode 103 with the insulating film 105 therebetween.

Claims

1. A field effect transistor comprising a source electrode, a drain electrode, a gate electrode, an insulating film and a semiconductor layer containing a crystalline oxide, wherein the source electrode and the drain electrode are self-aligned with the gate electrode with the insulating film therebetween.

2. The field effect transistor according to claim 1, wherein the semiconductor layer is between the source electrode and the drain electrode.

3. The field effect transistor according to claim 1, wherein the source electrode and the drain electrode are self-aligned with the gate electrode with the insulating film and the semiconductor layer therebetween.

4. The field effect transistor according to claim 1, wherein the semiconductor layer is on the source electrode and the drain electrode.

5. The field effect transistor according to claim 2, wherein the source electrode and the drain electrode each are a conductive amorphous oxide film which has almost the same composition as that of the semiconductor layer.

6. The field effect transistor according to claim 1, which has a coplanar structure.

7. The field effect transistor according to claim 1, wherein the crystalline oxide comprises at least In.

8. The field effect transistor according to claim 1, wherein the crystalline oxide is a composite oxide which comprises In and a positive divalent element or a positive trivalent element.

9. The field effect transistor according to claim 1, wherein the crystalline oxide has a bixbite structure.

10. A semiconductor apparatus which comprises the field effect transistor according to claim 1 and comprises a conductor which is in contact with the source electrode or the drain electrode of the field effect transistor.

11. A method for producing a bottom-gate type field effect transistor comprising:

forming a gate electrode;

forming an insulating film on the gate electrode;

forming a conductive amorphous oxide film on the insulating film; and

heating the gate electrode using as a mask a pattern of the gate electrode to crystallize a part of the conductive amorphous oxide film which overlaps the gate electrode to allow it to be semiconductive, and to form the source electrode and the drain electrode from a part of the conductive amorphous oxide film which does not overlap the gate electrode.

12. A method for producing a bottom-gate type field effect transistor comprising:

forming a gate electrode;

forming an insulating film on the gate electrode;

forming a conductive amorphous oxide film on the insulating film;

heating the conductive amorphous oxide film so that the oxide film is crystallized to be semiconductive; and

forming a source electrode and a drain electrode using as a mask a pattern of the gate electrode.

13. A method for producing a top-gate type field effect transistor comprising:

forming a conductive amorphous oxide film;

forming an insulating film on the conductive amorphous oxide film;

forming a gate electrode on the insulating film; and

heating the gate electrode using as a mask a pattern of the gate electrode to crystallize a part of the conductive amorphous oxide film which overlaps the gate electrode to allow it to be semiconductive, and to form the source electrode and the drain electrode from a part of the conductive amorphous oxide film which does not overlap the gate electrode.

14. A method for forming a top-gate type field effect transistor comprising:

forming a source electrode and a drain electrode;

forming a conductive amorphous oxide film on the source electrode and the drain electrode;

forming an insulating film on the conductive amorphous oxide film;

forming a gate electrode on the insulating film using as a mask patterns of the source electrode and the drain electrode; and

heating the conductive amorphous oxide film so that the oxide film is crystallized to be semiconductive.

15. A method for producing a field effect transistor comprising a step of heating the gate electrode to 200 to 1400°

C. and, by using heat transmitted from the gate electrode, subjecting at least part of a conductive amorphous oxide film to solid-phase crystallization to allow it to be semiconductive.