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US5227334A
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LPCVD process for depositing titanium nitride (tin) films and silicon substrates produced thereby
Assignee: Micron Technology Inc
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Filing: 1991-10-31
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Granted: 1993-07-13
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Expires: 2011-10-31
Abstract
Abstract A process for depositing titanium nitride films on silicon substrates or the like which includes reacting nitrogen trifluoride, NF 3 , with a titanium containing reactant gas, such as a titanium containing metal organic precursor, in a low pressure chemical vapor deposition reaction chamber. This CVD chamber is preferably a single wafer chamber operated at a pressure between 0.1 and 10.0 Torr and at a elevated temperature on the order of about 500° C. This process is most useful, for example, in the formation of low resistivity, highly conformal coatings of TiN on the surfaces of vias etched vertically in silicon integrated circuits and adapted to receive a selected heavy metal such as tungsten in direct contact therewith.
Inventors
- 👤 Gurtej S. Sandhu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:27
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
74 words
A process for depositing titanium nitride films on silicon substrates which includes the steps of: a. heating a silicon substrate to an elevated temperature within a reaction chamber operated at a negative pressure, and b. introducing a mixture of tetramethylamidotitanium (TMAT), nitrogen trifluoride, and a selected carrier and dilution gas into said reaction chamber to deposit titanium nitride films on the surface of said silicon wafer in accordance with the following equation: TMAT+NF.sub.3 →TiN+fluorocarbons+amines.
Claim 2
Dependent Claim
74 words
A process for depositing titanium nitride films on silicon substrates which includes the steps of: a. heating a silicon substrate to an elevated temperature within a reaction chamber operated at a negative pressure, and b. introducing a mixture of tetramethylamidotitanium (TMAT), nitrogen trifluoride, and a selected carrier and dilution gas into said reaction chamber to deposit titanium nitride films on the surface of said silicon wafer in accordance with the following equation: TMAT+NF.sub.3 →TiN+fluorocarbons+amines.
Claim 3
Dependent Claim
23 words
The process defined in claim 1 wherein said titanium containing reactant gas is TMAT and said selected carrier and dilution gas is helium.
Claim 4
Dependent Claim
28 words
The process defined in claim 1 wherein said silicon substrate is heated to a temperature of approximately 500° C. at a preselected pressure between 0.1 and 10.0 Torr.
Claim 5
Dependent Claim
41 words
The process defined in claim 1 wherein said TMAT and said carrier and dilution gas are passed into a premixing chamber at a flow rate of about 50 sccm and said NF 3 flow rate is set at about 200 sccm.
Claim 6
Dependent Claim
29 words
The process defined in claim 2 wherein said silicon substrate is heated to a temperature of approximately 500° C. at a preselected pressure of between 0.1 and 10.0 Torr.
Claim 7
Dependent Claim
41 words
The process defined in claim 5 wherein said TMAT and said carrier and dilution gas are passed into a premixing chamber at a flow rate of about 50 sccm and said NF 3 flow rate is set at about 200 sccm.
Claim 8
Dependent Claim
110 words
A process for forming vertical electrical interconnects in silicon integrated circuits which includes the steps of: a. providing a silicon substrate having layers of conductor and dielectric thereon, b. opening vias through said conductor or dielectric layers to expose a surface area of said silicon substrate, c. exposing said substrate to a mixture of a tetramethylamidotitanium (TMAT), nitrogen trifluoride, and a selected carrier and dilution gas in a CVD reaction chamber to deposit a titanium nitride coating on the surface of said silicon substrate in accordance with the following equation: TMAT+NF.sub.3 →TiN+fluorocarbons+amines and, d. depositing a selected heavy metal in contact with said TiN coating to fill up said vias.
Claim 9
Dependent Claim
110 words
A process for forming vertical electrical interconnects in silicon integrated circuits which includes the steps of: a. providing a silicon substrate having layers of conductor and dielectric thereon, b. opening vias through said conductor or dielectric layers to expose a surface area of said silicon substrate, c. exposing said substrate to a mixture of a tetramethylamidotitanium (TMAT), nitrogen trifluoride, and a selected carrier and dilution gas in a CVD reaction chamber to deposit a titanium nitride coating on the surface of said silicon substrate in accordance with the following equation: TMAT+NF.sub.3 →TiN+fluorocarbons+amines and, d. depositing a selected heavy metal in contact with said TiN coating to fill up said vias.
Claim 10
Dependent Claim
15 words
The process defined in claim 7 wherein said selected carrier and dilution gas is helium.
Claim 11
Dependent Claim
28 words
The process defined in claim 7 wherein said silicon substrate is heated to a temperature of approximately 500° C. at a preselected pressure between 0.1 and 10.0 Torr.
Claim 12
Dependent Claim
41 words
The process defined in claim 7 wherein said TMAT and said carrier and dilution gas are passed into a premixing chamber at a flow rate of about 50 sccm and said NF 3 flow rate is set at about 200 sccm.
Claim 13
Dependent Claim
29 words
The process defined in claim 8 wherein said silicon substrate is heated to a temperature of approximately 500° C. at a preselected pressure of between 0.1 to 10.0 Torr.
Claim 14
Dependent Claim
41 words
The process defined in claim 11 wherein said TMAT and said carrier and dilution gas are passed into a premixing chamber at a flow rate of about 50 sccm and said NF 3 flow rate is set at about 200 sccm.
Claim 15
Dependent Claim
25 words
A process for forming a TiN film on a selected substrate which includes reacting NF 3 with tetramethylamidotitanium, TMAT in the presence of said substrate.
Claim 16
Dependent Claim
25 words
A process for forming a TiN film on a selected substrate which includes reacting NF 3 with tetramethylamidotitanium, TMAT in the presence of said substrate.
Claim 17
Dependent Claim
26 words
The process defined in claim 13 wherein the reaction is carried out in a chemical vapor deposition chamber at an elevated temperature and a negative pressure.
Claim 18
Dependent Claim
18 words
The process defined in claim 14 wherein the reaction proceeds in accordance with the following equation: TMAT+NF.sub.3 →TiN+fluorocarbons+amines.
Claim 19
Dependent Claim
23 words
The process defined in claim 15 wherein said TiN films are formed within vias on integrated circuit substrates and then coated with tungsten.
Claim 20
Dependent Claim
24 words
The process defined in claim 13 wherein said titanium nitride films are formed within vias on integrated circuit substrates and then coated with tungsten.
Claim 21
Dependent Claim
39 words
The process defined in claim 17 wherein the reaction is carried out in a chemical vapor deposition chamber at a predetermined elevated temperature on the order of about 500° C. and a predetermined pressure between 0.1 and 10.0 Torr.
References Cited (Backward Citations)
US4897709A
Cited
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