EP0440154A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Two step process for forming an oxide layer over a stepped surface of a semiconductor wafer
Assignee: Applied Materials Inc
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Filing: 1991-01-29
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Granted: —
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Expires: 2011-01-29
Abstract
Abstract A two step process is disclosed for forming a silicon oxide layer (40,50) over a stepped surface of a semiconductor wafer (10) while inhibiting the formation of voids in the oxide layer which comprises depositing a layer (40) of an oxide of silicon over a stepped surface of the semiconductor wafer (10) in a CVD chamber by flowing into the chamber a gaseous mixture comprising a source of oxygen, a portion of which comprises O₃, 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 (50) of oxide over the first layer (40) in a CVD chamber by flowing into the chamber a gaseous mixture comprising a source of oxygen, a portion of which comprises O₃; 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 Wai-Man Lee
- 👤 David Nin-Kou Wang
- 👤 Makoto Nagashima
- 👤 Kazuto Fukuma
- 👤 Tatsuya Sato
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 18:26
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: 10
Claim 1
Independent Claim
174 words
A two step process for forming a silicon oxide layer over a stepped surface of a semiconductor wafer which comprises: a) depositing a 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, preferably 500 Torr, to about 760 Torr; and b) depositing a second layer of oxide over said first layer in a CVD chamber by flowing into said chamber a gaseous mixture comprising a source of oxygen, preferably at least a portion of which comprises O₃, and tetraethylorthosilicate as the gaseous source of silicon, while maintaining said CVD chamber at a lower pressure than during said first deposition step, preferably within a range of from about 40 Torr to about 250 Torr, preferably 100 Torr, such that the formation of voids in the oxide layer is inhibited.
Claim 2
Dependent Claim
38 words
The process of claim 1 wherein at least one, preferably both 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 3
Dependent Claim
52 words
The process of claim 1 or 2, 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 4
Dependent Claim
72 words
The process of any preceding claim, 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 and preferably with said second step being carried out until about 1 micron of oxide has been deposited on horizontal surfaces of said wafer.
Claim 5
Dependent Claim
27 words
The process of any preceding claim which further comprises maintaining a wafer temperature during said deposition steps within a range of from about 300°C to about 600°C.
Claim 6
Dependent Claim
39 words
The process of any preceding claim 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 7
Dependent Claim
37 words
The process of any preceding claim 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 8
Dependent Claim
30 words
The process of any preceding claim which further comprises maintaining a ratio of TEOS to O₃ within a range of from about 1:100 to about 2:1 during said deposition steps.
Claim 9
Dependent Claim
55 words
The process of any preceding claim wherein said process further includes providing at least 1 vol.% O₃ in said gaseous source of oxygen with the balance comprising one or more gases selected from the class consisting of O₂, H₂O₂, helium, argon, and nitrogen, with at least 10 vol.% of such gases comprising an oxygen-containing gas.
Claim 10
Dependent Claim
75 words
The process of any preceding claim 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 3,000 sccm during said deposition steps and/or 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.
References Cited (Backward Citations)
EP0212691A1
Cited
EP0272140A2
Cited
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