Patent EP0154483A2 successfully refreshed from Google Patents.
EP0154483A2
Expired / Lapsed
EP
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Improved pulsed plasma process
Assignee: Nortel Networks Ltd
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Filing: 1985-02-25
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Granted: —
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Expires: 2005-02-25
Abstract
Abstract 57 In a pulsed radio frequency plasma deposition process the pulse repetition frequency is matched to the gas exchange rate. This is achieved by using a pulse width of 50 to 500 microseconds and a pulse repetition rate corresponding to the time within which gas is exchanged in the reaction region.
Inventors
- 👤 Rudolf August Herbert Heinecke
- 👤 Suresh Mishrilal Ojha
- 👤 Ian Paul Llewellyn
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 02:57
CPC Classifications
C; C23; C23F; C23F4/00; C23C; C23C16/00; C23C16/44; C23C16/50; C23C16/515
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
65 words
A process for surface processing of a substrate material, including placing the substrate in an evacuated chamber, passing a gas through the chamber at reduced pressure, and applying high intensity pulsed radio frequency energy to the chamber to generate a plasma to which the substrate surface is exposed, wherein the pulse repetition frequency corresponds to the rate at which gas is exchanged within the chamber.
Claim 2
Dependent Claim
65 words
A process for surface processing of a substrate material, including placing the substrate in an evacuated chamber, passing a gas through the chamber at reduced pressure, and applying high intensity pulsed radio frequency energy to the chamber to generate a plasma to which the substrate surface is exposed, wherein the pulse repetition frequency corresponds to the rate at which gas is exchanged within the chamber.
Claim 3
Dependent Claim
20 words
A process as claimed in claim 1, wherein the pulse length of said pulse is from 50 to 500 microseconds.
Claim 4
Dependent Claim
17 words
A process as claimed in claim 2, wherein the pulse length is from 100 to 400 microseconds.
Claim 5
Dependent Claim
28 words
A process as claimed in claim 1, 2 or 3, wherein the partial pressure of the active components of the gas is from 10 to 100 m torr.
Claim 6
Dependent Claim
33 words
A process as claimed in any one of claims 1 to 4, wherein said gas is supplied as a series of pulses to said chamber, each gas pulse corresponding to a generator pulse.
Claim 7
Dependent Claim
18 words
A process as claimed in claim 5, wherein the composition of said gas is changed at each pulse.
Claim 8
Dependent Claim
18 words
A process as claimed in any one of claims 1 to 5, wherein said gas comprises an etchant.
Claim 9
Dependent Claim
14 words
A process as claimed in claim 7, wherein said substrate comprises a semiconductor structure.
Claim 10
Dependent Claim
22 words
A process as claimed in any one of claims 1 to 6, wherein a surface coating is applied to the substrate surface.
Claim 11
Dependent Claim
15 words
A process as claimed in claim 9, wherein said coating comprises a series of monolayers.
Claim 12
Dependent Claim
18 words
A process as claimed in claim 9 or 10, wherein said substrate comprises an infra-red lens or filter.
Claim 13
Dependent Claim
13 words
A process as claimed in claim 9, wherein said coating comprises silicon carbide.
Claim 14
Dependent Claim
19 words
A process as claimed in claim 12, wherein said coating is deposited from a mixture of silane and methane.
Claim 15
Dependent Claim
25 words
A process as claimed in any one of the preceding claims, wherein the plasma is exposed to a power density of at least 100 w/cc.
Claim 16
Dependent Claim
22 words
A process as claimed in any one of the preceding claims, wherein the pulse repetition frequency is from 5 to 10 Hz.
References Cited (Backward Citations)
No citation records indexed.
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