Patent US4134641A successfully refreshed from Google Patents.
Patent EP0617461A2 successfully refreshed from Google Patents.
EP0617461A2
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EP
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Oxynitride dielectric process for IC manufacture
Assignee: AT&T Inc
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Filing: 1994-03-16
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Granted: —
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Expires: 2014-03-16
Abstract
Abstract A method for making gate dielectrics (50) for MOS devices includes first forming a silicon oxynitride layer (70), and then forming a silicon dioxide layer (80) that underlies the oxynitride layer. The oxynitride layer functions as a membrane for controlled diffusion of oxygen to the oxidation region of the silicon substrate.
Inventors
- 👤 Young Ock Kim
- 👤 Lalita Manchanda
- 👤 Gary Robert Weber
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 12:24
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/01344; H10D64/60; H10D64/66; H10D64/68; H10D64/681; H10D64/685; H10D64/693; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6308; H10P14/6309; H10P14/6322; H10P14/6326; H10P14/6328; H10P14/6334; H10P14/66; H10P14/662; H10P14/668; H10P14/6681; H10P14/6682; H10D64/01346; H10P14/69; H10P14/692; H10P14/6921; H10P14/6922; H10P14/6927
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
106 words
A method for manufacturing at least one MOS device on a silicon substrate having a principal surface, the method comprising the steps of: a) forming a dielectric layer adjacent the principal surface; and b) depositing a gate electrode layer on the dielectric layer, CHARACTERIZED IN THAT (a) comprises the steps of: c) forming a silicon oxynitride layer; and d) after (c), subjecting the substrate to an oxidizing atmosphere such that chemical species comprising oxygen migrate through the oxynitride layer to a surface layer of the substrate and react therewith, resulting in a layer adjacent and underlying the silicon oxynitride layer, said underlying layer comprising silicon dioxide.
Claim 2
Dependent Claim
33 words
The method of claim 1, wherein (c) is carried out by chemical vapor deposition from an atmosphere comprising a gaseous compound of silicon and at least one gaseous compound of nitrogen and oxygen.
Claim 3
Dependent Claim
18 words
The method of claim 2, wherein the atmosphere comprises ammonia (NH₃), nitrous oxide (N₂O), and dichlorosilane (SiH₂ Cl₂).
Claim 4
Dependent Claim
30 words
The method of claim 1, wherein (c) is carried out by reacting a surface layer of the substrate in an atmosphere that comprises nitrous oxide (N₂O) or nitric oxide (NO).
Claim 5
Dependent Claim
18 words
The method of claim 1, wherein (d) is carried out at a temperature of at least about 900°C.
Claim 6
Dependent Claim
32 words
The method of claim 1, wherein (d) is carried out such that the resulting silicon-dioxide-comprising layer has a thickness of at least about 5 Å, but not more than about 30 Å.
Claim 7
Dependent Claim
26 words
The method of claim 1, wherein (c) comprises forming an oxynitride layer at least about 30 Å thick, but not more than about 70 Å thick.
Claim 8
Dependent Claim
43 words
The method of claim 1, wherein (c) is carried out such that the average ratio of the atomic concentration of nitrogen to the atomic concentration of oxygen in the resulting oxynitride layer is at least about 10%, but not more than about 40%.
Claim 9
Dependent Claim
12 words
The method of claim 8, wherein the average ratio is about 20%.
Claim 10
Dependent Claim
35 words
The method of claim 1, wherein (c) and (d) are carried out such that the resulting dielectric layer has a leakage current, at an applied field of 3 MV/cm, that is less than 1 nA/cm².
Claim 11
Dependent Claim
133 words
The method of claim 1, further comprising the steps of: e) patterning at least the gate electrode layer such that source and drain portions of the principal surface are defined, the source and drain regions being situated adjacent the gate electrode layer but not overlain thereby; f) implanting a dopant that comprises boron atoms into the gate electrode layer and into shallow portions of the substrate adjacent the source and drain portions of the principal surface; and g) heating the substrate such that a substantial portion of the boron atoms in the shallow substrate portions diffuse more deeply into the substrate; wherein: h) steps (c) and (d) are carried out such that during (g), no significant amount of boron diffuses from the gate electrode layer through the dielectric layer and into the substrate.
References Cited (Backward Citations)
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