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US5496410A Expired / Lapsed US ⏱️ 0.0 years remaining

Plasma processing apparatus and method of processing substrates by using same apparatus

Assignee: Hitachi Ltd
•
Filing: 1993-03-10
•
Granted: 1996-03-05
•
Expires: 2013-03-10
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Abstract

Abstract In a plasma processing apparatus which forms a gaseous raw material into a plasma by using electron cyclotron resonance and processes a substrate, leading-edge opening portions of an introduction tube into which a gaseous raw material is introduced are formed in the inner wall surface of the container in such a way that they do not project within the vacuum container. A heater is wound around the introduction pipe so that the opening portions thereof can be heated. With this construction, even if a gaseous raw material which is a liquid or solid at normal temperature and normal pressure is made to flow, the gaseous raw material can be prevented from being liquefied or solidified in the opening portions of the introduction pipe, and the opening portions of the introduction pipe can be prevented from being clogged. In addition, since there are no projections within the vacuum container, the propagation of microwaves is not impeded, making it possible to uniformity process the substrate.

Inventors

  • 👤 Takuya Fukuda
  • 👤 Michio Ohue
  • 👤 Kazuo Suzuki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 02:09
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32431; H01J37/3244; C; C23; C23C; C23C16/00; C23C16/44; C23C16/4401; C23C16/448; C23C16/4481; C23C16/455; C23C16/50; C23C16/511

Claims Analysis

Total Claims: 38
Claim 1
Independent Claim 130 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a liquid or solid raw material and for supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the containers, the gas supply means including gas supply structure and said opening portion, none of the gas supply means extending into the container; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating said gas supply structure and said opening portion of the gas supply means including in a vicinity of the vacuum container.
Claim 2
Dependent Claim 130 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a liquid or solid raw material and for supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the containers, the gas supply means including gas supply structure and said opening portion, none of the gas supply means extending into the container; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating said gas supply structure and said opening portion of the gas supply means including in a vicinity of the vacuum container.
Claim 3
Dependent Claim 56 words
A plasma processing apparatus according to claim 1, wherein the gas supply means has a plurality of opening portions provided in the vicinity of said vacuum container, and the gas supply means is positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma.
Claim 4
Dependent Claim 25 words
A plasma processing apparatus according to claim 1, wherein said processing means has magnetic-field generating means for inducing electron cyclotron resonance and microwave guide means.
Claim 5
Dependent Claim 194 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; first gas supply means for gasifying a first liquid or solid raw material and supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, the first gas supply means including gas supply structure and said opening portion, none of the first gas supply means extending into the container; second gas supply means for gasifying a second liquid or solid raw material and supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in the inner wall of the container, the second gas supply means including gas supply structure and said opening portion; processing means for subjecting the supplied gas to electron cyclotron resonance conditions, to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for independently heating the gas supply structure and opening portions of both the first and second gas supply means including in a vicinity of the vacuum container, to temperatures independent of each other.
Claim 6
Dependent Claim 194 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; first gas supply means for gasifying a first liquid or solid raw material and supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, the first gas supply means including gas supply structure and said opening portion, none of the first gas supply means extending into the container; second gas supply means for gasifying a second liquid or solid raw material and supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in the inner wall of the container, the second gas supply means including gas supply structure and said opening portion; processing means for subjecting the supplied gas to electron cyclotron resonance conditions, to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for independently heating the gas supply structure and opening portions of both the first and second gas supply means including in a vicinity of the vacuum container, to temperatures independent of each other.
Claim 7
Dependent Claim 62 words
A plasma processing apparatus according to claim 4, wherein the first and second gas supply means have a plurality of opening portions provided in the vicinity of said vacuum container, and the first and second gas supply means are positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma.
Claim 8
Dependent Claim 25 words
A plasma processing apparatus according to claim 4, wherein said processing means has magnetic-field generating means for inducing electron cyclotron resonance and microwave guide means.
Claim 9
Dependent Claim 143 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a plurality of liquid or solid raw materials and supplying the gasified liquid or solid raw materials to the vacuum container through an opening portion provided in an inner wall of the container, the gas supply means including gas supply structure and said opening portion, the gas supply means terminating at the inner wall of the container, none of the gas supply means extending into the container; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the gas supply structure and the opening portion of the gas supply means including in the vicinity of the vacuum container.
Claim 10
Dependent Claim 143 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a plurality of liquid or solid raw materials and supplying the gasified liquid or solid raw materials to the vacuum container through an opening portion provided in an inner wall of the container, the gas supply means including gas supply structure and said opening portion, the gas supply means terminating at the inner wall of the container, none of the gas supply means extending into the container; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the gas supply structure and the opening portion of the gas supply means including in the vicinity of the vacuum container.
Claim 11
Dependent Claim 56 words
A plasma processing apparatus according to claim 7, wherein the gas supply means has a plurality of opening portions provided in the vicinity of said vacuum container, and the gas supply means is positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma.
Claim 12
Dependent Claim 25 words
A plasma processing apparatus according to claim 7, wherein said processing means has magnetic-field generating means for inducing electron cyclotron resonance and microwave guide means.
Claim 13
Dependent Claim 174 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; first gas supply means for supplying a first gaseous raw material to the vacuum container through an opening portion provided in an inner wall of the container, the first gas supply means terminating at the inner wall of the container, none of the first gas supply means extending into the container; second gas supply means for gasifying a liquid or solid second raw material and supplying the gasified second raw material to the vacuum container through a second opening portion provided in the inner wall of the container, the second gas supply means including gas supply structure and said second opening portion; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the gas supply structure and second opening portion of the second gas supply means including in the vicinity of the vacuum container.
Claim 14
Dependent Claim 174 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; first gas supply means for supplying a first gaseous raw material to the vacuum container through an opening portion provided in an inner wall of the container, the first gas supply means terminating at the inner wall of the container, none of the first gas supply means extending into the container; second gas supply means for gasifying a liquid or solid second raw material and supplying the gasified second raw material to the vacuum container through a second opening portion provided in the inner wall of the container, the second gas supply means including gas supply structure and said second opening portion; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the gas supply structure and second opening portion of the second gas supply means including in the vicinity of the vacuum container.
Claim 15
Dependent Claim 33 words
A plasma processing apparatus according to claim 4, wherein the second gas supply means terminates at the inner wall of the container, none of the second gas supply means extending into the container.
Claim 16
Dependent Claim 33 words
A plasma processing apparatus according to claim 10, wherein the second gas supply means terminates at the inner wall of the container, none of the second gas supply means extending into the container.
Claim 17
Dependent Claim 51 words
A plasma processing apparatus according to claim 1, wherein the processing means includes a means for introducing microwaves into the container, and the means for introducing microwaves introduces the microwaves into the container in a direction parallel to a surface of the workpiece to be processed by the plasma processing apparatus.
Claim 18
Dependent Claim 77 words
A plasma processing apparatus according to claim 1, wherein the processing means includes a means for introducing microwaves into the container, wherein the means for introducing microwaves introduces the microwaves into the container in a direction perpendicular to a surface of the workpiece to be processed by the plasma processing apparatus, and wherein the gas supply means is positioned so as to supply the gasified liquid or solid raw material in a direction oblique to said surface.
Claim 19
Dependent Claim 160 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is to be placed; gas supply means for gasifying a liquid or solid raw material so as to form an obtained gas; a gas guide tube for leading the obtained gas from the gas supply means into the vacuum container through an opening portion provided in an inner wall of the vacuum container, the gas guide tube having a first part, and a leading end which is attached in alignment with the inner wall of the vacuum container; processing means for forming the obtained gas into a plasma by subjecting the obtained gas to electron cyclotron resonance conditions; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the gas flowing through the first part and the leading end of the gas guide tube, including the gas reaching the opening portion, the heating means extending to the opening portion.
Claim 20
Dependent Claim 160 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is to be placed; gas supply means for gasifying a liquid or solid raw material so as to form an obtained gas; a gas guide tube for leading the obtained gas from the gas supply means into the vacuum container through an opening portion provided in an inner wall of the vacuum container, the gas guide tube having a first part, and a leading end which is attached in alignment with the inner wall of the vacuum container; processing means for forming the obtained gas into a plasma by subjecting the obtained gas to electron cyclotron resonance conditions; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the gas flowing through the first part and the leading end of the gas guide tube, including the gas reaching the opening portion, the heating means extending to the opening portion.
Claim 21
Dependent Claim 257 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is to be placed; first gas supply means for gasifying a first liquid or solid raw material so as to form a first obtained gas; a first gas guide tube for leading the first obtained gas from the first gas supply means into the vacuum container through an opening portion provided in an inner wall of the vacuum container, the first gas guide tube having a first portion and having a leading end attached in alignment with the inner wall of the vacuum container; second gas supply means for gasifying a second liquid or solid raw material so as to form a second obtained gas; a second gas guide tube for leading the second obtained gas from the second gas supply means into the vacuum container through an opening portion provided in the inner wall of the container, the second gas guide tube having a first portion and having a leading end attached in alignment with the inner wall of the vacuum container; processing means for respectively forming the gases supplied from the first and second gas supply means into plasmas by subjecting the gases to electron cyclotron resonance conditions; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for separately heating the supplied gases flowing through the first portions and leading ends of the first and second gas guide tubes, including the gases reaching the respective opening portions, the heating means extending to the opening portions.
Claim 22
Dependent Claim 257 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is to be placed; first gas supply means for gasifying a first liquid or solid raw material so as to form a first obtained gas; a first gas guide tube for leading the first obtained gas from the first gas supply means into the vacuum container through an opening portion provided in an inner wall of the vacuum container, the first gas guide tube having a first portion and having a leading end attached in alignment with the inner wall of the vacuum container; second gas supply means for gasifying a second liquid or solid raw material so as to form a second obtained gas; a second gas guide tube for leading the second obtained gas from the second gas supply means into the vacuum container through an opening portion provided in the inner wall of the container, the second gas guide tube having a first portion and having a leading end attached in alignment with the inner wall of the vacuum container; processing means for respectively forming the gases supplied from the first and second gas supply means into plasmas by subjecting the gases to electron cyclotron resonance conditions; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for separately heating the supplied gases flowing through the first portions and leading ends of the first and second gas guide tubes, including the gases reaching the respective opening portions, the heating means extending to the opening portions.
Claim 23
Dependent Claim 244 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is to be placed; first gas supply means for supplying a first gas; a first gas guide tube for leading the gas supplied from the first gas supply means into the vacuum container through an opening portion provided in an inner wall of the vacuum container, a leading end of the first gas guide tube being attached in alignment with the inner wall of the vacuum container; second gas supply means for gasifying a raw liquid or solid material so as to form an obtained gas; a second gas guide tube for leading the gas supplied from the second gas supply means into the vacuum container through an opening portion provided on the inner wall of the vacuum container, the second gas guide tube having a first portion and having a leading end attached in alignment with the inner wall of the vacuum container; processing means for forming the gases supplied from the first and second gas supply means into a plasma by subjecting the gases supplied from the first and second gas supply means to electron cyclotron resonance conditions; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the supplied gas flowing through the first portion and the leading end of the second gas guide tube, including the gas reaching the opening portion, the heating means extending to the opening portion.
Claim 24
Dependent Claim 244 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is to be placed; first gas supply means for supplying a first gas; a first gas guide tube for leading the gas supplied from the first gas supply means into the vacuum container through an opening portion provided in an inner wall of the vacuum container, a leading end of the first gas guide tube being attached in alignment with the inner wall of the vacuum container; second gas supply means for gasifying a raw liquid or solid material so as to form an obtained gas; a second gas guide tube for leading the gas supplied from the second gas supply means into the vacuum container through an opening portion provided on the inner wall of the vacuum container, the second gas guide tube having a first portion and having a leading end attached in alignment with the inner wall of the vacuum container; processing means for forming the gases supplied from the first and second gas supply means into a plasma by subjecting the gases supplied from the first and second gas supply means to electron cyclotron resonance conditions; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the supplied gas flowing through the first portion and the leading end of the second gas guide tube, including the gas reaching the opening portion, the heating means extending to the opening portion.
Claim 25
Dependent Claim 27 words
A plasma processing apparatus according to claim 1, wherein said gas supply structure extends from a source of the liquid or solid material to said opening portion.
Claim 26
Dependent Claim 40 words
A plasma processing apparatus according to claim 4, wherein the gas supply structures of the first and second gas supply means each extend from respective sources of the first and second liquid or solid raw materials to respective opening portions.
Claim 27
Dependent Claim 28 words
A plasma processing apparatus according to claim 7, wherein said gas supply structure extends from a source of the liquid or solid raw materials to said opening portions.
Claim 28
Dependent Claim 35 words
A plasma processing apparatus according to claim 10, wherein the gas supply structure of the second gas supply means extends from a source of the liquid or solid second raw material to the opening portion.
Claim 29
Dependent Claim 160 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a liquid or solid raw material and for supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, none of the gas supply means extending into the container, wherein the gas supply means has a plurality of opening portions provided in the vicinity of said vacuum container, and the gas supply means is positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating an opening portion of the gas supply means in a vicinity of the vacuum container.
Claim 30
Dependent Claim 160 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a liquid or solid raw material and for supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, none of the gas supply means extending into the container, wherein the gas supply means has a plurality of opening portions provided in the vicinity of said vacuum container, and the gas supply means is positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating an opening portion of the gas supply means in a vicinity of the vacuum container.
Claim 31
Dependent Claim 216 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; first gas supply means for gasifying a first liquid or solid raw material and supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, none of the first gas supply means extending into the container; second gas supply means for gasifying a second liquid or solid raw material and supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in the inner wall of the container; wherein the first and second gas supply means have a plurality of opening portions provided in the vicinity of said vacuum container and the first and second gas supply means are positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma; processing means for subjecting the supplied gas to electron cyclotron resonance conditions, to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for independently heating the opening portions of the first and second gas supply means in a vicinity of the vacuum container, to temperatures independent of each other.
Claim 32
Dependent Claim 216 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; first gas supply means for gasifying a first liquid or solid raw material and supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, none of the first gas supply means extending into the container; second gas supply means for gasifying a second liquid or solid raw material and supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in the inner wall of the container; wherein the first and second gas supply means have a plurality of opening portions provided in the vicinity of said vacuum container and the first and second gas supply means are positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma; processing means for subjecting the supplied gas to electron cyclotron resonance conditions, to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for independently heating the opening portions of the first and second gas supply means in a vicinity of the vacuum container, to temperatures independent of each other.
Claim 33
Dependent Claim 173 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a plurality of liquid or solid raw materials and supplying the gasified liquid or solid raw materials to the vacuum container through an opening portion provided in an inner wall of the container, the gas supply means terminating at the inner wall of the container, none of the gas supply means extending into the container, wherein the gas supply means has a plurality of opening portions provided in the vicinity of said vacuum container, and the gas supply means is positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the opening portions of the gas supply means in the vicinity of the vacuum containers.
Claim 34
Dependent Claim 173 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a plurality of liquid or solid raw materials and supplying the gasified liquid or solid raw materials to the vacuum container through an opening portion provided in an inner wall of the container, the gas supply means terminating at the inner wall of the container, none of the gas supply means extending into the container, wherein the gas supply means has a plurality of opening portions provided in the vicinity of said vacuum container, and the gas supply means is positioned such that gas flow through all the opening portions is provided perpendicularly to a surface of said workpiece exposed to the plasma; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating the opening portions of the gas supply means in the vicinity of the vacuum containers.
Claim 35
Dependent Claim 155 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a liquid or solid raw material and for supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, none of the gas supply means extending into the container; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom, wherein the processing means includes a means for introducing microwaves into the container, and the means for introducing microwaves introduces the microwaves into the container in a direction parallel to a surface of the workpiece to be processed by the plasma processing apparatus; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating an opening portion of the gas supply means in a vicinity of the vacuum container.
Claim 36
Dependent Claim 155 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a liquid or solid raw material and for supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, none of the gas supply means extending into the container; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom, wherein the processing means includes a means for introducing microwaves into the container, and the means for introducing microwaves introduces the microwaves into the container in a direction parallel to a surface of the workpiece to be processed by the plasma processing apparatus; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating an opening portion of the gas supply means in a vicinity of the vacuum container.
Claim 37
Dependent Claim 181 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a liquid or solid raw material and for supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, none of the gas supply means extending into the container; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom, wherein the processing means includes a means for introducing microwaves into the container, wherein the means for introducing microwaves introduces the microwaves into the container in a direction perpendicular to a surface of the workpiece to be processed by the plasma processing apparatus, and wherein the gas supply means is positioned so as to supply the gasified liquid or solid raw material in a direction oblique to said surface; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating an opening portion of the gas supply means in a vicinity of the vacuum container.
Claim 38
Dependent Claim 181 words
A plasma processing apparatus, comprising: a vacuum container in which a workpiece is placed; gas supply means for gasifying a liquid or solid raw material and for supplying the gasified liquid or solid raw material to the vacuum container through an opening portion provided in an inner wall of the container, none of the gas supply means extending into the container; processing means for subjecting the supplied gas to electron cyclotron resonance conditions to form a plasma therefrom, wherein the processing means includes a means for introducing microwaves into the container, wherein the means for introducing microwaves introduces the microwaves into the container in a direction perpendicular to a surface of the workpiece to be processed by the plasma processing apparatus, and wherein the gas supply means is positioned so as to supply the gasified liquid or solid raw material in a direction oblique to said surface; evacuation means for maintaining the inside of the vacuum container at a vacuum condition; and heating means for heating an opening portion of the gas supply means in a vicinity of the vacuum container.

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USPTO Annuity & Maintenance Windows

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7.5 Years (Year 8) 2003-03-05 2003-09-04 2004-03-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-03-05 2007-09-04 2008-03-05 $7700.00 Window Closed / Lapsed

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