US4725560A
Expired / Lapsed
US
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Silicon oxynitride storage node dielectric
Assignee: International Business Machines Corp
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Filing: 1986-09-08
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Granted: 1988-02-16
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Expires: 2006-09-08
Abstract
Abstract An annealing process carried out at 800° C. in a wet O 2 ambient permits the manufacture of a reliable storage capacitor wherein the dielectric layer is comprised of silicon oxynitride formed by low pressure chemical vapor deposition (LPCVD). The manufacturing process includes first depositing the silicon oxynitride film by LPCVD, second annealing in wet O 2 at 800° C. or N 2 at 1000° C., third forming an N-type region in the silicon substrate by As + ion implantation through the silicon oxynitride film, fourth annealing in wet O 2 at 800° C., and fifth depositing an electrode.
Inventors
- 👤 John R. Abernathey
- 👤 David L. Johnson
- 👤 Pai-Hung Pan
- 👤 Charles A. Paquette
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:58
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6921; H10P14/6922; H10P14/6927; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/0134; H10D64/01344; H10D64/60; H10D64/66; H10D64/68; H10D64/693; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6334; H10P14/65; H10P14/6516; H10P14/6529; H10P30/00; H10P30/20; H10P30/202; H10P30/204; H10P30/21; H10P30/212; H10P30/28; H10P14/694; H10P14/6943; H10P14/69433; Y; Y10; Y10S; Y10S148/00; Y10S148/003; Y10S148/013; Y10S148/014; Y10S148/114
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
89 words
A method of forming a thin film of silicon oxynitride exhibiting a high breakdown voltage on a silicon substrate of a first conductivity type, comprising the steps of: forming a thin film of silicon oxynitride on the silicon substrate; then forming a region of a second conductivity type in at least part of the silicon substrate by ion implantation through said thin film of silicon oxynitride; and then annealing said silicon oxynitride film in a wet O 2 ambient at a temperature above 700° C. and below 1000° C.
Claim 2
Independent Claim
89 words
A method of forming a thin film of silicon oxynitride exhibiting a high breakdown voltage on a silicon substrate of a first conductivity type, comprising the steps of: forming a thin film of silicon oxynitride on the silicon substrate; then forming a region of a second conductivity type in at least part of the silicon substrate by ion implantation through said thin film of silicon oxynitride; and then annealing said silicon oxynitride film in a wet O 2 ambient at a temperature above 700° C. and below 1000° C.
Claim 3
Dependent Claim
45 words
The method of forming a thin film of silicon oxynitride recited in claim 1, further comprising a first annealing step performed after depositing the thin film of silicon oxynitride but before the step of forming said region of said second conductivity type in the substrate.
Claim 4
Dependent Claim
33 words
The method of forming a thin film of silicon oxynitride recited in claim 2, wherein said first annealing step is carried out in an N 2 ambient at a temperature of 1000° C.
Claim 5
Independent Claim
122 words
A method of forming a capacitor structure on the surface of a semiconductor substrate of a first conductivity type, comprising the steps of: depositing a thin layer of silicon oxynitride on the substrate by use of a low pressure chemical vapor deposition process; then carrying out a first anneal on said layer of silicon oxynitride; then implanting dopant ions of a second conductivity type through said layer of silicon oxynitride to form an implanted region the substrate; then carrying out a second anneal on said layer of silicon oxynitride, said second anneal being carried out in a wet O 2 ambient at a temperature above 700° C. and below 1000° C.; and then forming an electrode on said layer of silicon oxynitride.
Claim 6
Independent Claim
122 words
A method of forming a capacitor structure on the surface of a semiconductor substrate of a first conductivity type, comprising the steps of: depositing a thin layer of silicon oxynitride on the substrate by use of a low pressure chemical vapor deposition process; then carrying out a first anneal on said layer of silicon oxynitride; then implanting dopant ions of a second conductivity type through said layer of silicon oxynitride to form an implanted region the substrate; then carrying out a second anneal on said layer of silicon oxynitride, said second anneal being carried out in a wet O 2 ambient at a temperature above 700° C. and below 1000° C.; and then forming an electrode on said layer of silicon oxynitride.
Claim 7
Dependent Claim
26 words
The method of forming a capacitor structure as recited in claim 4, wherein said layer of silicon oxynitride is less than approximately 15 nm in thickness.
Claim 8
Dependent Claim
26 words
The method of forming a capacitor structure as recited in claim 5, wherein said layer of silicon oxynitride has a refractive index between 1.65 and 1.85.
Claim 9
Dependent Claim
36 words
The method of forming a capacitor structure as recited in claim 4, wherein the first anneal step is carried out in a dry N 2 ambient at a temperature above 800° C. and below 1000° C.
Claim 10
Dependent Claim
36 words
The method of forming a capacitor structure as recited in claim 4, wherein the first anneal step is carried out in a wet O 2 ambient at a temperature above 700° C. and below 900° C.
Claim 11
Dependent Claim
19 words
The method of forming a capacitor structure as recited in claim 4, wherein said electrode is comprised of polysilicon.
Claim 12
Independent Claim
123 words
A method of forming a high capacitance storage capacitor for a dynamic random access memory cell formed on a semiconductor substrate of a first conductivity type, comprising the steps of: forming a thin layer of silicon oxynitride on the substrate by the use of a low pressure chemical vapor deposition technique; then carrying out a first anneal cycle in an N 2 ambient at a temperature of approximately 1000° C.; then implanting ions of a second conductivity type through said thin silicon oxynitride layer into a surface portion of the substrate; then carrying out a second anneal cycle in a wet O 2 ambient at a temperature of approximately 800° C.; and then forming an electrode on said thin layer of silicon oxynitride.
Claim 13
Independent Claim
123 words
A method of forming a high capacitance storage capacitor for a dynamic random access memory cell formed on a semiconductor substrate of a first conductivity type, comprising the steps of: forming a thin layer of silicon oxynitride on the substrate by the use of a low pressure chemical vapor deposition technique; then carrying out a first anneal cycle in an N 2 ambient at a temperature of approximately 1000° C.; then implanting ions of a second conductivity type through said thin silicon oxynitride layer into a surface portion of the substrate; then carrying out a second anneal cycle in a wet O 2 ambient at a temperature of approximately 800° C.; and then forming an electrode on said thin layer of silicon oxynitride.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-15 | 1991-08-17 | 1992-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-15 | 1995-08-17 | 1996-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-15 | 1999-08-17 | 2000-02-16 | $7700.00 | Window Closed / Lapsed |