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EP0200951A2
Expired / Lapsed
EP
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Anisotropic silicon etching in fluorinated plasma
Assignee: International Business Machines Corp
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Filing: 1986-04-11
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Granted: —
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Expires: 2006-04-11
Abstract
Abstract A method of high rate anisotropic etching of silicon in a high pressure plasma is described. The etching ambient is a mixture of either NF3 or SF 6 , N 2 , and a polymerizing gas such as CHF 3 that creates conditions necessary for anisotropy not normally possible with nonpolymerizing fluorinated gases in a high pressure regime. The etch process is characterized by high etch rates and good uniformity utilizing photoresist or similar materials as a mask. In one embodiment the present process is used to etch deep trenches in silicon using a photoresist mask.
Inventors
- 👤 Lee Chen
- 👤 Gangadhara Swami Mathad
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 01:59
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/24; H10P50/242
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
33 words
A method of etching a silicon body, comprising: placing said silicon body in a gaseous plasma environment including a fluorine containing gaseous compound, an inert gas, and a polymer for. ming gaseous compound.
Claim 2
Independent Claim
33 words
A method of etching a silicon body, comprising: placing said silicon body in a gaseous plasma environment including a fluorine containing gaseous compound, an inert gas, and a polymer for. ming gaseous compound.
Claim 3
Dependent Claim
23 words
The method of claim 1, wherein said silicon body has a patterned masking layer thereon, and the etching of the silicon is anisotropic.
Claim 4
Dependent Claim
22 words
The method of claim 2, wherein said silicon body to be etched comprises multiple layers of differently doped polysilicon and monocrystalline silicon.
Claim 5
Independent Claim
31 words
The method of claims 1 to 3, wherein said fluorine containing gas is selected from the group consisting of NF 3 and SF 6 , and said inert gas comprises nitrogen.
Claim 6
Independent Claim
22 words
The method of claims 1 to 4, wherein said polymer forming gas is selected from the group consisting of hydrogen containing freons.
Claim 7
Independent Claim
35 words
The method of claims 1 to 4, wherein said polymer forming gas is selected from the group consisting of CHF., C 2 F 4 , C 2 F 6 and C 3 F 8 .
Claim 8
Independent Claim
39 words
The method of claims 1 to 6, wherein said gaseous plasma environment comprises a pressure of about 1 to 7 mbar and a power density of about 2 to 5 watts/cm 2 at the surface of said silicon body.
Claim 9
Dependent Claim
30 words
The method of claim 2, wherein said patterned masking layer comprises silicon dioxide and said polymer forming gaseous compound is selected from the group consisting of chlorine containing polymerizing gases.
References Cited (Backward Citations)
No citation records indexed.
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