US5464792A
Expired / Lapsed
US
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Process to incorporate nitrogen at an interface of a dielectric layer in a semiconductor device
Assignee: Apple Inc
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Filing: 1994-01-27
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Granted: 1995-11-07
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Expires: 2014-01-27
Abstract
Abstract Nitrogen is piled-up at a top interface of a gate dielectric layer by a process of the present invention. A gate dielectric layer (14) is formed on a substrate (12). A buffer layer (16), such as polysilicon, is formed on the dielectric layer. A nitrogen source layer (18), such as oxynitride, is formed on the buffer layer. The device is annealed to drive nitrogen from the source layer through the buffer layer and to an interface (15) between the polysilicon and the dielectric, resulting in a high nitrogen concentration at this interface. A nitrogen concentration may also be achieved at an interface (13) between the dielectric layer and the substrate.
Inventors
- 👤 Hsing-Huang Tseng
- 👤 Philip J. Tobin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:43
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D30/00; H10D30/01; H10D30/021; H10D30/0411; H10D64/01338; H10D64/031; H10D64/035; H10D64/60; H10D64/66; H10D64/68; H10D64/681; Y; Y10; Y10S; Y10S438/00; Y10S438/91
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
85 words
A process for fabricating a semiconductor device (10) comprising the steps of: providing a substrate (12); forming a first dielectric layer (14) on the substrate; depositing a buffer layer (16) on the first dielectric layer; depositing an oxynitride layer on the buffer layer; and annealing the device to diffuse nitrogen from the oxynitride layer through the buffer layer and into the first dielectric layer to create a region of high nitrogen concentration near an interface (15) between the buffer layer and the first dielectric layer.
Claim 2
Dependent Claim
85 words
A process for fabricating a semiconductor device (10) comprising the steps of: providing a substrate (12); forming a first dielectric layer (14) on the substrate; depositing a buffer layer (16) on the first dielectric layer; depositing an oxynitride layer on the buffer layer; and annealing the device to diffuse nitrogen from the oxynitride layer through the buffer layer and into the first dielectric layer to create a region of high nitrogen concentration near an interface (15) between the buffer layer and the first dielectric layer.
Claim 3
Dependent Claim
29 words
The process of claim 1 wherein the step of annealing comprises annealing the device using rapid thermal processing for a time period within a range of about 10-300 seconds.
Claim 4
Dependent Claim
16 words
The process of claim 1 wherein the step of depositing a buffer layer comprises depositing polysilicon.
Claim 5
Dependent Claim
17 words
The process of claim 1 wherein the step of depositing a buffer layer comprises depositing amorphous silicon.
Claim 6
Dependent Claim
29 words
The process of the claim 1 wherein the step of forming a first dielectric layer comprises forming a dielectric selected from a group consisting of silicon dioxide and oxynitride.
Claim 7
Dependent Claim
70 words
A process for fabricating a semiconductor device comprising the steps of: providing a substrate; forming a first dielectric layer on the substrate; depositing a buffer layer on the first dielectric layer; forming a nitrogen source layer on the buffer layer; and annealing the device to diffuse nitrogen from the source layer through the buffer layer to accumulate nitrogen at an interface between the buffer layer and the first dielectric layer.
Claim 8
Dependent Claim
70 words
A process for fabricating a semiconductor device comprising the steps of: providing a substrate; forming a first dielectric layer on the substrate; depositing a buffer layer on the first dielectric layer; forming a nitrogen source layer on the buffer layer; and annealing the device to diffuse nitrogen from the source layer through the buffer layer to accumulate nitrogen at an interface between the buffer layer and the first dielectric layer.
Claim 9
Dependent Claim
18 words
The process of claim 6 wherein the step of depositing a buffer layer comprises depositing a polysilicon layer.
Claim 10
Dependent Claim
17 words
The process of claim 6 wherein the step of depositing a buffer layer comprises depositing amorphous silicon.
Claim 11
Dependent Claim
19 words
The process of claim 6 wherein the step of depositing a nitrogen source layer comprises depositing an oxynitride layer.
Claim 12
Dependent Claim
29 words
The process of the claim 6 wherein the step of forming a first dielectric layer comprises forming a dielectric selected from a group consisting of silicon dioxide and oxynitride.
Claim 13
Dependent Claim
32 words
The process of claim 6 further comprising the steps of: removing the nitrogen source layer and the buffer layer; and forming a gate electrode (61 or 82) overlying the first dielectric layer.
Claim 14
Dependent Claim
72 words
A process for fabricating a semiconductor device comprising the steps of: providing a silicon substrate; forming a first dielectric layer on the substrate; depositing a silicon layer on the first dielectric layer; forming a second dielectric layer on the silicon layer, wherein the second dielectric layer comprises nitrogen; and diffusing nitrogen from the second dielectric layer through the silicon layer to an interface between the silicon layer and the first dielectric layer.
Claim 15
Dependent Claim
72 words
A process for fabricating a semiconductor device comprising the steps of: providing a silicon substrate; forming a first dielectric layer on the substrate; depositing a silicon layer on the first dielectric layer; forming a second dielectric layer on the silicon layer, wherein the second dielectric layer comprises nitrogen; and diffusing nitrogen from the second dielectric layer through the silicon layer to an interface between the silicon layer and the first dielectric layer.
Claim 16
Dependent Claim
29 words
The process of the claim 12 wherein the step of forming a first dielectric layer comprises forming a dielectric selected from a group consisting of silicon dioxide and oxynitride.
Claim 17
Dependent Claim
32 words
The process of claim 13 further comprising the steps of: removing the nitrogen source layer; and forming a gate electrode (61 or 82) overlying the first dielectric layer using the silicon layer.
Claim 18
Dependent Claim
57 words
The process of claim 14 wherein the step of depositing silicon comprises depositing a first layer of polysilicon, and wherein the step of forming a gate electrode comprises: after removing the nitrogen source layer, depositing a second polysilicon layer on the first polysilicon layer; and patterning the first and second polysilicon layers to form the gate electrode.
Claim 19
Dependent Claim
26 words
The process of claim 12 wherein the step of depositing a silicon layer comprises depositing a polysilicon layer having a thickness of between approximately 100-5000 angstroms.
Claim 20
Dependent Claim
17 words
The process of claim 12 wherein the step of depositing a buffer layer comprises depositing amorphous silicon.
Claim 21
Dependent Claim
19 words
The process of claim 12 wherein the step of forming a second dielectric layer comprises growing an oxynitride layer.
Claim 22
Dependent Claim
27 words
The process of claim 6 further comprising the steps of: removing the nitrogen source layer; and forming a gate electrode (61 or 82) from the buffer layer.
References Cited (Backward Citations)
JPH02114632A
Cited
US5063423A
Cited
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