US5314845A
Expired / Lapsed
US
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Two step process for forming void-free oxide layer over stepped surface of semiconductor wafer
Assignee: Applied Materials Inc
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Filing: 1990-02-02
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Granted: 1994-05-24
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Expires: 2010-02-02
Abstract
Abstract A two step process is disclosed for forming a silicon oxide layer over a stepped surface of a semiconductor wafer while inhibiting the formation of voids in the oxide layer which comprises depositing a layer of an oxide of silicon over a stepped surface of a semiconductor wafer in a CVD chamber by flowing into the chamber a gaseous mixture comprising a source of oxygen, a portion of which comprises O 3 , and tetraethylorthosilicate as the gaseous source of silicon while maintaining the pressure in the CVD chamber within a range of from about 250 Torr to about 760 Torr and then depositing a second layer of oxide over the first layer in a CVD chamber by flowing into the chamber a gaseous mixture comprising a source of oxygen, a portion of which comprises O 3 ; and tetraethylorthosilicate as the gaseous source of silicon while maintaining the CVD chamber at a lower pressure than during the first deposition step.
Inventors
- 👤 Peter W. Lee
- 👤 David N. Wang
- 👤 Makoto Nagashima
- 👤 Kazuto Fukuma
- 👤 Tatsuya Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:44
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6921; H10P14/6922; H10P14/6923; C; C23; C23C; C23C16/00; C23C16/22; C23C16/30; C23C16/40; C23C16/401; C23C16/402; H10P14/65; H10P14/6516; H10P14/6534; H10P14/66; H10P14/662; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/092; H10W20/40; H10W20/45; H10W20/48; H10W74/00; H10W74/10; H10W74/131; H10W74/137; H10W74/40; H10W74/43; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6334; H10P14/6336; H10P14/668; H10P14/6681; H10P14/6682; H10P14/6684; H10P14/6686; H10P14/69215
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
160 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer while inhibiting the formation of voids in the oxide layer which comprises: a) depositing a void-free first layer of an oxide of silicon over said stepped surface of said semiconductor wafer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen and tetraethylorthosilicate as the gaseous source of silicon, while maintaining the pressure in said CVD chamber within a range of from about 250 Torr to about 760 Torr to form said void-free oxide layer; and b) depositing a second layer of oxide over said void-free first oxide layer in said CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen and tetraethylorthosilicate as the gaseous source of silicone, while maintaining said CVD chamber at a pressure within a range of from about 40 Torr to below about 250 Torr.
Claim 2
Dependent Claim
160 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer while inhibiting the formation of voids in the oxide layer which comprises: a) depositing a void-free first layer of an oxide of silicon over said stepped surface of said semiconductor wafer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen and tetraethylorthosilicate as the gaseous source of silicon, while maintaining the pressure in said CVD chamber within a range of from about 250 Torr to about 760 Torr to form said void-free oxide layer; and b) depositing a second layer of oxide over said void-free first oxide layer in said CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen and tetraethylorthosilicate as the gaseous source of silicone, while maintaining said CVD chamber at a pressure within a range of from about 40 Torr to below about 250 Torr.
Claim 3
Dependent Claim
31 words
The process of claim 1 wherein the pressure in said CVD chamber during said first deposition step is maintained within a range of from about 300 Torr to about 760 Torr.
Claim 4
Dependent Claim
31 words
The process of claim 2 wherein the pressure in said CVD chamber during said second deposition step is maintained within a range of from about 40 Torr to about 200 Torr.
Claim 5
Dependent Claim
31 words
The process of claim 3 wherein the pressure in said CVD chamber during said first deposition step is maintained within a range of from about 500 Torr to about 760 Torr.
Claim 6
Dependent Claim
31 words
The process of claim 4 wherein the pressure in said CVD chamber during said second deposition step is maintained within a range of from about 40 Torr to about 100 Torr.
Claim 7
Dependent Claim
36 words
The process of claim 1 wherein at least one of said deposition steps is carried out while maintaining a plasma in said CVD chamber at a power level of from about 25 to about 500 watts.
Claim 8
Dependent Claim
36 words
The process of claim 1 wherein both said first and second deposition steps are carried out while maintaining a plasma in said CVD chamber at a power level of from about 25 to about 500 watts.
Claim 9
Dependent Claim
50 words
The process of claim 1 wherein one or both of said deposition steps are carried out while also flowing one or more additional gases into said CVD chamber selected from the class consisting of a gaseous source of boron, a gaseous source of phosphorus, or a mixture of such gases.
Claim 10
Dependent Claim
179 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer while inhibiting the formation of voids in the oxide layer which comprises: a) depositing a void-free first layer of an oxide of silicon over said stepped surface of said semiconductor wafer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen, at least a portion of which comprises O 3 , and tetraethylorthosilicate as the gaseous source of silicon, while maintaining the pressure in said CVD chamber within a range of from about 500 Torr to about 760 Torr to form said void-free oxide layer; and b) depositing a second layer of oxide over said void-free first oxide layer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen, at least a portion of which comprises O 3 , and tetraethylorthosilicate as the gaseous source of silicon, while maintaining said CVD chamber at a pressure within a range of from about 40 Torr to about 100 Torr.
Claim 11
Dependent Claim
179 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer while inhibiting the formation of voids in the oxide layer which comprises: a) depositing a void-free first layer of an oxide of silicon over said stepped surface of said semiconductor wafer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen, at least a portion of which comprises O 3 , and tetraethylorthosilicate as the gaseous source of silicon, while maintaining the pressure in said CVD chamber within a range of from about 500 Torr to about 760 Torr to form said void-free oxide layer; and b) depositing a second layer of oxide over said void-free first oxide layer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen, at least a portion of which comprises O 3 , and tetraethylorthosilicate as the gaseous source of silicon, while maintaining said CVD chamber at a pressure within a range of from about 40 Torr to about 100 Torr.
Claim 12
Dependent Claim
47 words
The process of claim 9 wherein said first step is carried out until low regions on said stepped surface between raised portions of said surface are filled with oxide up to at least the original level of adjoining regions of said stepped surface prior to said deposition.
Claim 13
Dependent Claim
27 words
The process of claim 10 wherein said second step is carried out until about 1 micron of oxide has been deposited on horizontal surfaces of said wafer.
Claim 14
Dependent Claim
28 words
The process of claim 9 which further comprises maintaining a wafer temperature during said deposition steps within a range of from about 300° C. to about 600° C.
Claim 15
Dependent Claim
38 words
The process of claim 9 which further comprises maintaining a flow rate into said vacuum chamber of said gaseous source of oxygen within a range of from about 500 sccm to about 10,000 sccm during said deposition steps.
Claim 16
Dependent Claim
36 words
The process of claim 9 which further comprises maintaining a flow rate into said vacuum chamber of said gaseous TEOS within a range of from about 100 sccm to about 10,000 sccm during said deposition steps.
Claim 17
Dependent Claim
30 words
The process of claim 9 which further comprises maintaining a ratio of TEOS to O 3 within a range of from about 1:100 to about 2:1 during said deposition steps.
Claim 18
Dependent Claim
63 words
The process of claim 9 wherein said process further includes providing at least 1 vol. % O 3 in said gaseous source of oxygen with the balance comprising one or more gases selected from the class consisting of O 2 , H 2 O 2 , helium, argon, and nitrogen, with at least 10 vol. % of such gases comprising an oxygen-containing gas.
Claim 19
Dependent Claim
50 words
The process of claim 9 wherein one or both of said deposition steps are carried out while also flowing one or more additional gases into said CVD chamber selected from the class consisting of a gaseous source of boron, a gaseous source of phosphorus, or a mixture of such gases.
Claim 20
Dependent Claim
38 words
The process of claim 17 which further comprises maintaining a flow rate into said vacuum chamber of each of said additional gases within a range of from about 10 sccm to about 3000 sccm during said deposition steps.
Claim 21
Dependent Claim
43 words
The process of claim 18 which further comprises maintaining a total flow rate into said vacuum chamber of said gaseous sources of boron, phosphorus, oxygen, and TEOS within a range of from about 650 sccm to about 20,000 sccm during said deposition steps.
Claim 22
Dependent Claim
34 words
The process of claim 9 wherein at least said second step is carried out while maintaining a plasma in said CVD chamber at a power level of from about 25 to about 500 watts.
Claim 23
Dependent Claim
34 words
The process of claim 9 wherein at least said first step is carried out while maintaining a plasma in said CVD chamber at a power level of from about 25 to about 500 watts.
Claim 24
Dependent Claim
36 words
The process of claim 9 wherein both said first and second deposition steps are carried out while maintaining a plasma in said CVD chamber at a power level of from about 25 to about 500 watts.
Claim 25
Dependent Claim
281 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer while inhibiting the formation of voids in the oxide layer which comprises: a) depositing a void-free first layer of an oxide of silicon over said stepped surface of said semiconductor wafer in a CVD chamber by flowing into said chamber a gaseous mixture comprising: i) a source of oxygen, at least 1 vol. % of which comprises O 3 , with the balance comprising one or more gases selected from the class consisting of O 2 , H 2 O 2 , helium, argon, and nitrogen, with at least 10 vol. % of such gases comprising an oxygen-containing gas; and ii) tetraethylorthosilicate as the gaseous source of silicon; while maintaining a ratio of TEOS to O 3 in said gaseous mixture within a range of from about 1:100 to 2:1 during said deposition of said first layer; b) maintaining the pressure in said CVD chamber within a range of from about 500 Torr to about 760 Torr; and c) then depositing a second layer of oxide over said void-free first oxide layer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen, at least 1 vol. % of which comprises O 3 ; and tetraethylorthosilicate as the gaseous source of silicon, while maintaining said CVD chamber during said deposition of said second oxide layer at a pressure within a range of from about 40 Torr to about 100 Torr and while maintaining a ratio of TEOS to O 3 within a range of from about 1:100 to about 2:1 during said deposition of said second layer.
Claim 26
Dependent Claim
281 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer while inhibiting the formation of voids in the oxide layer which comprises: a) depositing a void-free first layer of an oxide of silicon over said stepped surface of said semiconductor wafer in a CVD chamber by flowing into said chamber a gaseous mixture comprising: i) a source of oxygen, at least 1 vol. % of which comprises O 3 , with the balance comprising one or more gases selected from the class consisting of O 2 , H 2 O 2 , helium, argon, and nitrogen, with at least 10 vol. % of such gases comprising an oxygen-containing gas; and ii) tetraethylorthosilicate as the gaseous source of silicon; while maintaining a ratio of TEOS to O 3 in said gaseous mixture within a range of from about 1:100 to 2:1 during said deposition of said first layer; b) maintaining the pressure in said CVD chamber within a range of from about 500 Torr to about 760 Torr; and c) then depositing a second layer of oxide over said void-free first oxide layer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen, at least 1 vol. % of which comprises O 3 ; and tetraethylorthosilicate as the gaseous source of silicon, while maintaining said CVD chamber during said deposition of said second oxide layer at a pressure within a range of from about 40 Torr to about 100 Torr and while maintaining a ratio of TEOS to O 3 within a range of from about 1:100 to about 2:1 during said deposition of said second layer.
Claim 27
Dependent Claim
182 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer which will form void-free oxide in low regions between raised portions of the wafer which comprises: a) depositing silicon oxide over said stepped surface of said semiconductor wafer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen and tetraethylorthosilicate as the gaseous source of silicon, while maintaining the pressure in said CVD chamber within a range of from about 250 Torr to about 760 Torr until said low regions on said stepped surface between said raised portions of said surface are filled with oxide up to at least the original level of said raised portions of said stepped surface prior to said deposition, to form said void-free oxide; and b) depositing further oxide over said void-free oxide on said wafer in said CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen and tetraethylorthosilicate as the gaseous source of silicon, while maintaining said CVD chamber at a pressure below 250 Torr.
Claim 28
Dependent Claim
182 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer which will form void-free oxide in low regions between raised portions of the wafer which comprises: a) depositing silicon oxide over said stepped surface of said semiconductor wafer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen and tetraethylorthosilicate as the gaseous source of silicon, while maintaining the pressure in said CVD chamber within a range of from about 250 Torr to about 760 Torr until said low regions on said stepped surface between said raised portions of said surface are filled with oxide up to at least the original level of said raised portions of said stepped surface prior to said deposition, to form said void-free oxide; and b) depositing further oxide over said void-free oxide on said wafer in said CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen and tetraethylorthosilicate as the gaseous source of silicon, while maintaining said CVD chamber at a pressure below 250 Torr.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-05-23 | 1997-11-22 | 1998-05-24 | $2000.00 | Window Closed / Lapsed |
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