SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF

• US 20170062619A1
• Filed: 08/12/2016
• Published: 03/02/2017
• Est. Priority Date: 08/26/2015
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: SASAGAWA, Shinya, HAMADA, Takashi, SHIMOMURA, Akihisa, OKAMOTO, Satoru, TOCHIBAYASHI, Katsuaki
• Granted Patent: US 9,773,919 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/465 Chemical or electrical treatment, e.g. electrolytic etching to form insulating layers H01L21/469
• CPC Class Codes: H01L 21/47573 Etching the layer
• CPC Class Codes: H01L 21/47635 After-treatment of these layers
• CPC Class Codes: H01L 27/1207 combined with devices in contact with the semiconductor body, i.e. bulk/SOI hybrid circuits
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 29/42372 characterised by the conducting layer, e.g. the length, the sectional shape or the lay-out H01L29/42324 takes precedence
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• 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 29/78648 arranged on opposing sides of the channel
• 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 minute transistor is provided. A transistor with low parasitic capacitance is provided. A transistor having high frequency characteristics is provided. A transistor having a high on-state current is provided. A semiconductor device including the transistor is provided. A semiconductor device having a high degree of integration is provided. A semiconductor device including an oxide semiconductor; a second insulator; a second conductor; a third conductor; a fourth conductor; a fifth conductor; a first conductor and a first insulator embedded in an opening portion formed in the second insulator, the second conductor, the third conductor, the fourth conductor, and the fifth conductor; a region where a side surface and a bottom surface of the second conductor are in contact with the fourth conductor; and a region where a side surface and a bottom surface of the third conductor are in contact with the fifth conductor.

Claims

1. A semiconductor device comprising:

an oxide semiconductor;

a first conductor;

a second conductor;

a third conductor;

a fourth conductor;

a fifth conductor;

a first insulator;

a second insulator; and

a third insulator,

wherein the second insulator is provided with an opening portion penetrating through the second insulator,

whereina region of a bottom surface of the opening portion is in contact with the oxide semiconductor,

whereina region of the first insulator is in contact with a side surface and the bottom surface of the opening portion,

whereina region of the first conductor faces the side surface and the bottom surface of the opening portion with the first insulator positioned therebetween,

whereinthe second conductor, the third conductor, the fourth conductor, and the fifth conductor are positioned between the oxide semiconductor and the second insulator,

whereina region of a side surface of the second conductor and a bottom surface of the second conductor is in contact with the fourth conductor,

whereina region of a side surface of the third conductor and a bottom surface of the third conductor is in contact with the fifth conductor, and

whereina region of the third insulator is in contact with the oxide semiconductor.

2. The semiconductor device according to claim 1, wherein the third insulator comprises at least one of main constituent elements of the oxide semiconductor other than oxygen.

3. The semiconductor device according to claim 1,

wherein a region of a fourth insulator is in contact with the first insulator, and

wherein the fourth insulator comprises at least one of main constituent elements of the oxide semiconductor other than oxygen.

4. The semiconductor device according to claim 1, wherein the first conductor comprises a region functioning as a gate electrode of a transistor having a gate line width longer than or equal to 3 nm and shorter than or equal to 60 nm.

5. The semiconductor device according to claim 1, further comprising a region in which a distance between an end portion of the second conductor and an end portion of the third conductor facing the second conductor is longer than or equal to 5 nm and shorter than or equal to 80 nm.

6. A method for manufacturing a semiconductor device, comprising the steps of:

forming a second insulator over a first insulator;

forming an oxide semiconductor over the second insulator;

forming a third insulator over the oxide semiconductor;

forming a resist mask over the third insulator by a lithography method;

etching part of the third insulator using the resist mask as an etching mask to form, in the third insulator, an opening portion for exposing a top surface of the oxide semiconductor;

forming a first conductor over the third insulator and the exposed top surface of the oxide semiconductor;

forming a second conductor over the first conductor;

polishing the second conductor and the first conductor to expose the third insulator;

etching the exposed portion of the third insulator;

etching the oxide semiconductor and the second insulator using the first conductor and the second conductor as an etching mask until the first insulator is exposed;

forming a fourth insulator over the first insulator, the first conductor, and the second conductor;

forming, in the fourth insulator, an opening portion for exposing the second conductor;

forming, in the second conductor, an opening portion for exposing the first conductor to divide the second conductor into a first conductor layer and a second conductor layer;

forming, in the first conductor, an opening portion for exposing the oxide semiconductor to divide the first conductor into a third conductor layer and a fourth conductor layer;

forming a fifth insulator over the fourth insulator and the oxide semiconductor;

forming a third conductor over the fifth insulator; and

polishing the third conductor and the fifth insulator to expose the fourth insulator,

wherein the second insulator comprises at least one of main constituent elements of the oxide semiconductor other than oxygen.

7. A method for manufacturing a semiconductor device, comprising the steps of:

forming a second insulator over a first insulator;

forming an oxide semiconductor over the second insulator;

forming a third insulator over the oxide semiconductor;

forming a resist mask over the third insulator by a lithography method;

etching part of the third insulator using the resist mask as an etching mask to form, in the third insulator, an opening portion for exposing a top surface of the oxide semiconductor;

forming a first conductor over the third insulator and the exposed top surface of the oxide semiconductor;

forming a second conductor over the first conductor;

polishing the second conductor and the first conductor to expose the third insulator;

etching the exposed portion of the third insulator;

etching the oxide semiconductor and the second insulator using the first conductor and the second conductor as an etching mask until the first insulator is exposed;

forming a fourth insulator over the first insulator, the first conductor, and the second conductor;

forming, in the fourth insulator, an opening portion for exposing the second conductor;

forming, in the second conductor, an opening portion for exposing the first conductor to divide the second conductor into a first conductor layer and a second conductor layer;

forming, in the first conductor, an opening portion for exposing the oxide semiconductor to divide the first conductor into a third conductor layer and a fourth conductor layer;

forming a fifth insulator over the fourth insulator and the oxide semiconductor;

forming a sixth insulator over the fifth insulator;

forming a third conductor over the sixth insulator; and

polishing the third conductor, the sixth insulator, and the fifth insulator to expose the fourth insulator,

wherein the second insulator comprises at least one of main constituent elements of the oxide semiconductor other than oxygen.

8. A method for manufacturing a semiconductor device, comprising the steps of:

forming a second insulator over a first insulator;

forming an oxide semiconductor over the second insulator;

forming a first conductor over the oxide semiconductor;

forming a third insulator over the first conductor;

forming a resist mask over the third insulator by a lithography method;

etching part of the third insulator using the resist mask as an etching mask to form, in the third insulator, an opening portion for exposing a top surface of the first conductor;

forming a second conductor over the third insulator and at least the exposed top surface of the first conductor;

polishing the second conductor to expose the third insulator;

etching the exposed portion of the third insulator and part of the first conductor;

etching the oxide semiconductor and the second insulator using the first conductor and the second conductor as an etching mask until the first insulator is exposed;

forming a fourth insulator over the first insulator and the second conductor;

forming, in the fourth insulator, an opening portion for exposing the second conductor;

forming, in the second conductor, an opening portion for exposing the first conductor to divide the second conductor into a first conductor layer and a second conductor layer;

forming, in the first conductor, an opening portion for exposing the oxide semiconductor to divide the first conductor into a third conductor layer and a fourth conductor layer;

forming a fifth insulator over the fourth insulator and the oxide semiconductor;

forming a third conductor over the fifth insulator; and

polishing the third conductor and the fifth insulator to expose the fourth insulator,

wherein the second insulator comprises at least one of main constituent elements of the oxide semiconductor other than oxygen.

9. A method for manufacturing a semiconductor device, comprising the steps of:

forming a second insulator over a first insulator;

forming an oxide semiconductor over the second insulator;

forming a first conductor over the oxide semiconductor;

forming a third insulator over the first conductor;

forming a resist mask over the third insulator by a lithography method;

etching part of the third insulator using the resist mask as an etching mask to form, in the third insulator, an opening portion for exposing a top surface of the first conductor;

forming a second conductor over the third insulator and at least the exposed top surface of the first conductor;

polishing the second conductor to expose the third insulator;

etching the exposed portion of the third insulator and part of the first conductor;

etching the oxide semiconductor and the second insulator using the first conductor and the second conductor as an etching mask until the first insulator is exposed;

forming a fourth insulator over the first insulator and the second conductor;

forming, in the fourth insulator, an opening portion for exposing the second conductor;

forming, in the second conductor, an opening portion for exposing the first conductor to divide the second conductor into a first conductor layer and a second conductor layer;

forming, in the first conductor, an opening portion for exposing the oxide semiconductor to divide the first conductor into a third conductor layer and a fourth conductor layer;

forming a fifth insulator over the fourth insulator and the oxide semiconductor;

forming a sixth insulator over the fifth insulator;

forming a third conductor over the sixth insulator; and

polishing the third conductor, the sixth insulator, and the fifth insulator to expose the fourth insulator,

wherein the second insulator comprises at least one of main constituent elements of the oxide semiconductor other than oxygen.