US5747866A
Expired / Lapsed
US
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Application of thin crystalline Si3 N4 liners in shallow trench isolation (STI) structures
Assignee: Infineon Technologies AG
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Filing: 1997-01-21
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Granted: 1998-05-05
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Expires: 2017-01-21
Abstract
Abstract Silicon integrated circuits use a crystalline layer of silicon nitride (Si 3 N 4 ) in shallow trench isolation (STI) structures as an O 2 -barrier film. The crystalline Si 3 N 4 lowers the density of electron traps as compared with as-deposited, amorphous Si 3 N 4 . Further, a larger range of low-pressure chemical-vapor deposited (LPCVD) Si 3 N 4 films can be deposited, providing a larger processing window for thickness controllability. An LPCVD-Si 3 N 4 film is deposited at temperatures of 720° C. to 780° C. The deposited film is in an amorphous state. Subsequently, a high-temperatures rapid-thermal anneal in pure nitrogen or ammonia is conducted at 1050° C. to 1100° for 60 seconds.
Inventors
- 👤 Herbert Ho
- 👤 Erwin Hammerl
- 👤 David M. Dobuzinsky
- 👤 Herbert Palm
- 👤 Stephen Fugardi
- 👤 Atul Ajmera
- 👤 James F. Moseman
- 👤 Samuel C. Ramac
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:18
CPC Classifications
H; H10; H10P; H10P95/00; H10P14/00; H10P14/60; H10P14/61; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/014; H10W10/10; H10W10/17; Y; Y10; Y10S; Y10S148/00; Y10S148/05
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
44 words
An improved shallow trench isolation (STI) structure for submicron integrated circuit devices comprising: a shallow trench of 0.5 μm or less etched in a silicon substrate; and a thin crystalline Si 3 N 4 liner 5 to 10 nm thick in said shallow trench.
Claim 2
Dependent Claim
44 words
An improved shallow trench isolation (STI) structure for submicron integrated circuit devices comprising: a shallow trench of 0.5 μm or less etched in a silicon substrate; and a thin crystalline Si 3 N 4 liner 5 to 10 nm thick in said shallow trench.
Claim 3
Dependent Claim
40 words
The improved STI structure recited in claim 1 further comprising a thin thermal oxide film of approximately 10 nm thickness grown in said shallow trench, said thin crystalline Si 3 N 4 liner being formed over the thin thermal oxide.
Claim 4
Dependent Claim
59 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure comprising: a shallow trench of 0.5 μm or less etched in a silicon substrate; and, a converted Si 3 N 4 film 5 to 10 nm thick deposited by low-pressure chemical-vapor deposition (LPCVD) at a temperature between 720° C. to 780° C.
Claim 5
Dependent Claim
59 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure comprising: a shallow trench of 0.5 μm or less etched in a silicon substrate; and, a converted Si 3 N 4 film 5 to 10 nm thick deposited by low-pressure chemical-vapor deposition (LPCVD) at a temperature between 720° C. to 780° C.
Claim 6
Dependent Claim
64 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 3 wherein immediately after deposition of Si 3 N 4 film, a rapid thermal anneal is conducted between 1050° C. and 1150° C. for approximately 60 seconds therefore converting said Si 3 N 4 film from an amorphous state to a crystalline state.
Claim 7
Dependent Claim
34 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 4 wherein said rapid thermal anneal is conducted at 1100° C. or less.
Claim 8
Dependent Claim
32 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 4 wherein said rapid thermal anneal is conducted in pure nitrogen.
Claim 9
Dependent Claim
31 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 4 wherein said rapid thermal anneal is conducted in ammonia.
Claim 10
Dependent Claim
78 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure comprising: a shallow trench of 0.5 μm or less etched in a silicon substrate; a thermal oxide layer of approximately 10 nm thickness coating said shallow trench; and, a converted Si 3 N 4 film of 5 to 10 nm thickness deposited over said thermal oxide layer by low-pressure chemical-vapor deposition (LPCVD) at a temperature between 720° C. to 780° C.
Claim 11
Dependent Claim
78 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure comprising: a shallow trench of 0.5 μm or less etched in a silicon substrate; a thermal oxide layer of approximately 10 nm thickness coating said shallow trench; and, a converted Si 3 N 4 film of 5 to 10 nm thickness deposited over said thermal oxide layer by low-pressure chemical-vapor deposition (LPCVD) at a temperature between 720° C. to 780° C.
Claim 12
Dependent Claim
73 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 8 wherein said converted Si 3 N 4 film is formed by conducting a rapid thermal anneal between 1050° C. and 1150° C. immediately after deposition of Si 3 N 4 film, for approximately 60 seconds, therefore converting said Si 3 N 4 film from an amorphous state to a crystalline state.
Claim 13
Dependent Claim
34 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 9 wherein said rapid thermal anneal is conducted at 1100° C. or less.
Claim 14
Dependent Claim
32 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 9 wherein said rapid thermal anneal is conducted in pure nitrogen.
Claim 15
Dependent Claim
31 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 9 wherein said rapid thermal anneal is conducted in ammonia.
Claim 16
Dependent Claim
30 words
A crystalline silicone nitride (Si 3 N 4 ) film in a shallow trench isolation (STI) structure as claimed in claim 8 wherein said thermal oxide layer removes etch damage.
References Cited (Backward Citations)
US4918028A
Cited
US5085711A
Cited
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