US5643640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorine doped plasma enhanced phospho-silicate glass, and process
Assignee: International Business Machines Corp
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Filing: 1995-11-27
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Granted: 1997-07-01
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Expires: 2015-11-27
Abstract
Abstract A fluorinated phosphosilicate glass (FPSG) is produced in a plasma-enhanced chemical vapor deposition process (PECVD) in which the plasma source comprises conventional phosphosilicate glass-forming materials together with one or more fluorine gas-forming materials. The deposited fluorine-gas enhances the filling of gaps or voids with dielectric glass compositions by etching the top of the via holes or gaps during the filling operation. The present fluorine-doped phosphosilicate glass compositions are stable compared to conventional phosphosilicate glass compositions which are relatively unstable and unsatisfactory for use as gap-filling dielectric glass compositions.
Inventors
- 👤 Ashima B. Chakravarti
- 👤 Terry M. Cheng
- 👤 Son Van Nguyen
- 👤 Michael Shapiro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:18
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/11; C03C3/112; C23; C23C; C23C16/00; C23C16/22; C23C16/30; C23C16/40; C23C16/401
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
106 words
Process for producing improved phosphosilicate glass dielectric compositions while reducing the dielectric constant thereof, which comprises introducing a supply of at least one fluorine-containing reactive gas to a chemical vapor deposition chamber containing reactive phosphosilicate glass-forming gases under a vacuum pressure and at a temperature between about 400° and 500° C., creating a plasma of said gases, and depositing said plasma as a fluorine-doped phosphosilicate glass dielectric containing between about 0.1 and 3 mole % of fluorine, said dielectric being capable of filling vias in a single continuous operation and having a lower dielectric constant than a corresponding dielectric composition produced in the absence of fluorine.
Claim 2
Dependent Claim
106 words
Process for producing improved phosphosilicate glass dielectric compositions while reducing the dielectric constant thereof, which comprises introducing a supply of at least one fluorine-containing reactive gas to a chemical vapor deposition chamber containing reactive phosphosilicate glass-forming gases under a vacuum pressure and at a temperature between about 400° and 500° C., creating a plasma of said gases, and depositing said plasma as a fluorine-doped phosphosilicate glass dielectric containing between about 0.1 and 3 mole % of fluorine, said dielectric being capable of filling vias in a single continuous operation and having a lower dielectric constant than a corresponding dielectric composition produced in the absence of fluorine.
Claim 3
Dependent Claim
141 words
A process for depositing a fluorine-containing phosphosilicate glass dielectric layer on a silicon layer comprising the step of: (a) supporting said silicon layer on a lower electrode having a positive uniformly spaced from an upper electrode connected to a source of RF energy, within chemical vapor deposition chamber connected to sources of a silicon-containing reactive gas and a phosphorous-containing reactive gas as phosphosilicate glass-forming reactants, and to a source of a fluorine-containing reactive gas; (b) creating a vacuum within said chamber; (c) introducing reactive proportions of said gases to said chamber while applying an RF potential across said electrodes, to create a gas plasma of said reactive gases; (d) depositing a film of said plasma in the surface of said silicon layer in the form of a stable, fluorine-containing phosphosilicate glass containing between about 0.1 and 3 mole % of fluorine.
Claim 4
Dependent Claim
141 words
A process for depositing a fluorine-containing phosphosilicate glass dielectric layer on a silicon layer comprising the step of: (a) supporting said silicon layer on a lower electrode having a positive uniformly spaced from an upper electrode connected to a source of RF energy, within chemical vapor deposition chamber connected to sources of a silicon-containing reactive gas and a phosphorous-containing reactive gas as phosphosilicate glass-forming reactants, and to a source of a fluorine-containing reactive gas; (b) creating a vacuum within said chamber; (c) introducing reactive proportions of said gases to said chamber while applying an RF potential across said electrodes, to create a gas plasma of said reactive gases; (d) depositing a film of said plasma in the surface of said silicon layer in the form of a stable, fluorine-containing phosphosilicate glass containing between about 0.1 and 3 mole % of fluorine.
Claim 5
Dependent Claim
33 words
Process according to claim 2 in which said silicon layer contains at least one wide gap via, and the layer deposited in step (d) completely fills said via in a single continuous operation.
Claim 6
Dependent Claim
21 words
Process according to claim 1 in which said phosphosilicate glass-forming gases include a silicon-containing reactive gas and a phosphorous-containing reactive gas.
Claim 7
Dependent Claim
14 words
Process according to claim 1 in which said fluorine-containing gas comprises ethyl hexafluoride gas.
Claim 8
Dependent Claim
14 words
Process according to claim 2 in which said silicon-containing reactive gas comprises tetraethoxy silane.
Claim 9
Dependent Claim
14 words
Process according to claim 2 in which said phosphorous-containing reactive gas comprises trimethyl phosphate.
Claim 10
Dependent Claim
14 words
Process according to claim 2 in which said fluorine-containing gas comprises ethyl hexafluoride gas.
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| 3.5 Years (Year 4) | 2000-06-30 | 2000-12-30 | 2001-07-01 | $2000.00 | Window Closed / Lapsed |
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