# US 9,040,989 B2 · Semiconductor device and manufacturing method thereof

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,040,989 B2
- Document ID: US9040989B2
- Status: Granted
- Kind: B2
- Application number: 14/021,406
- Filed: 2013-09-09
- Published: 2014-01-09
- Granted: 2015-05-26
- Earliest claimed: 2009-12-08
- Assignees: Semiconductor Energy Laboratory Co., Ltd.
- Applicants: Semiconductor Energy Laboratory Co., Ltd.
- Inventors: Shunpei Yamazaki
- Web page: https://patentgrep.com/patent/US9040989B2

## CPC

- H10D 30/6756: {Amorphous oxide semiconductors}
- H10D 30/6755: {Oxide semiconductors, e.g. zinc oxide, copper aluminium oxide or cadmium stannate}
- H10D 86/423: {comprising semiconductor materials not belonging to the Group IV, e.g. InGaZnO}
- H10D 86/60: wherein the TFTs are in active matrices
- H10P 95/94: {Hydrogenation or deuterisation, e.g. using atomic hydrogen from a plasma}
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10

## Abstract

One embodiment of the present invention is to achieve high mobility in a device using an oxide semiconductor and provide a highly reliable display device. An oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction substantially perpendicular to a surface is formed and an oxide insulating layer is formed over and in contact with the oxide semiconductor layer. Oxygen is supplied to the oxide semiconductor layer by third heat treatment. A nitride insulating layer containing hydrogen is formed over the oxide insulating layer and fourth heat treatment is performed, so that hydrogen is supplied at least to an interface between the oxide semiconductor layer and the oxide insulating layer.

## Claims

### Claim 1

A semiconductor device comprising:
a first gate electrode;
an oxide semiconductor layer over the first gate electrode, the oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction, wherein an angle between the direction and a surface of the oxide semiconductor layer is within a range of 80° to 100°;
a second gate electrode over the oxide semiconductor layer;
a nitride insulating layer containing hydrogen over the oxide semiconductor layer.

### Claim 2 (depends on 1)

The semiconductor device according to claim 1, wherein the oxide semiconductor layer is in a non-single-crystal state.

### Claim 3 (depends on 1)

The semiconductor device according to claim 1, wherein the second gate electrode is positioned under the nitride insulating layer.

### Claim 4 (depends on 1)

The semiconductor device according to claim 1, wherein off-state current density of a transistor comprising the oxide semiconductor layer is 100 aA/μm or less.

### Claim 5 (depends on 1)

The semiconductor device according to claim 1, wherein off-state resistivity of a transistor comprising the oxide semiconductor layer is greater than or equal to 1×109 Ω·m.

### Claim 6 (depends on 1)

The semiconductor device according to claim 1, wherein the oxide semiconductor layer comprises In—Ga—Zn—O based oxide.

### Claim 7

A semiconductor device comprising:
a first gate electrode;
an oxide semiconductor layer over the first gate electrode, the oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction, wherein an angle between the direction and a surface of the oxide semiconductor layer is within a range of 80° to 100°;
an oxide insulating layer over the oxide semiconductor layer;
a second gate electrode over the oxide semiconductor layer;
a nitride insulating layer containing hydrogen over the oxide insulating layer.

### Claim 8 (depends on 7)

The semiconductor device according to claim 7, wherein the oxide semiconductor layer is in a non-single-crystal state.

### Claim 9 (depends on 7)

The semiconductor device according to claim 7, wherein the second gate electrode is positioned between the oxide insulating layer and the nitride insulating layer.

### Claim 10 (depends on 7)

The semiconductor device according to claim 7, wherein off-state current density of a transistor comprising the oxide semiconductor layer is 100 aA/μm or less.

### Claim 11 (depends on 7)

The semiconductor device according to claim 7, wherein off-state resistivity of a transistor comprising the oxide semiconductor layer is greater than or equal to 1×109 Ω·m.

### Claim 12 (depends on 7)

The semiconductor device according to claim 7, wherein the oxide semiconductor layer comprises In—Ga—Zn—O based oxide.

### Claim 13

A semiconductor device comprising:
a first conductive layer;
an oxide semiconductor layer over the first conductive layer, the oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction, wherein an angle between the direction and a surface of the oxide semiconductor layer is within a range of 80° to 100°;
a source electrode electrically connected to the oxide semiconductor layer;
a drain electrode electrically connected to the oxide semiconductor layer;
a second conductive layer over the oxide semiconductor layer;
a nitride insulating layer containing hydrogen over the oxide semiconductor layer.

### Claim 14 (depends on 13)

The semiconductor device according to claim 13, wherein each of the first conductive layer and the second conductive layer is a gate electrode.

### Claim 15 (depends on 13)

The semiconductor device according to claim 13, further comprising an oxide insulating layer between the oxide semiconductor layer and the nitride insulating layer.

### Claim 16 (depends on 13)

The semiconductor device according to claim 13, wherein the oxide semiconductor layer is in a non-single-crystal state.

### Claim 17 (depends on 13)

The semiconductor device according to claim 13, wherein the second conductive layer is positioned under the nitride insulating layer.

### Claim 18 (depends on 13)

The semiconductor device according to claim 13, wherein off-state current density of a transistor comprising the oxide semiconductor layer is 100 aA/μm or less.

### Claim 19 (depends on 13)

The semiconductor device according to claim 13, wherein off-state resistivity of a transistor comprising the oxide semiconductor layer is greater than or equal to 1×109 Ω·m.

### Claim 20 (depends on 13)

The semiconductor device according to claim 13, wherein the oxide semiconductor layer comprises In—Ga—Zn—O based oxide.

### Claim 21

A semiconductor device comprising:
a first conductive layer;
an oxide semiconductor layer over the first conductive layer, the oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction substantially perpendicular to a surface of the oxide semiconductor layer;
a source electrode electrically connected to the oxide semiconductor layer;
a drain electrode electrically connected to the oxide semiconductor layer;
a second conductive layer over the oxide semiconductor layer;
a nitride insulating layer containing hydrogen over the oxide semiconductor layer,
wherein the oxide semiconductor layer comprises an oxide comprising indium.

### Claim 22 (depends on 21)

The semiconductor device according to claim 21, wherein each of the first conductive layer and the second conductive layer is a gate electrode.

### Claim 23 (depends on 21)

The semiconductor device according to claim 21, further comprising an oxide insulating layer between the oxide semiconductor layer and the nitride insulating layer.

### Claim 24 (depends on 21)

The semiconductor device according to claim 21, wherein the oxide semiconductor layer is in a non-single-crystal state.

### Claim 25 (depends on 21)

The semiconductor device according to claim 21, wherein the second conductive layer is positioned under the nitride insulating layer.

### Claim 26 (depends on 21)

The semiconductor device according to claim 21, wherein off-state current density of a transistor comprising the oxide semiconductor layer is 100 aA/μm or less.

### Claim 27 (depends on 21)

The semiconductor device according to claim 21, wherein off-state resistivity of a transistor comprising the oxide semiconductor layer is greater than or equal to 1×109 Ω·m.

### Claim 28 (depends on 21)

The semiconductor device according to claim 21, wherein the oxide semiconductor layer comprises In—Ga—Zn—O based oxide.