Stock material or miscellaneous articles – Composite – Of metal
Reexamination Certificate
2001-08-03
2004-08-31
Jones, Deborah (Department: 1775)
Stock material or miscellaneous articles
Composite
Of metal
C701S066000, C701S066000, C701S066000, C701S066000
Reexamination Certificate
active
06783863
ABSTRACT:
TECHNICAL FIELD
This invention relates to an internal member for plasma-treating vessel having an excellent resistance to plasma erosion and a method of producing the same.
Particularly, the invention is a technique capable of applying to members used in a plasma treatment under a plasma environment using a treating gas containing a halogen element such as deposit shield, baffle plate, focus ring, insulator ring, shield ring, bellows cover, electrode and so on.
Moreover, the invention is applicable to internal parts for plasma-treating vessels in a field of a semiconductor manufacturing device, a manufacturing apparatus for a liquid crystal device or the like.
BACKGROUND ART
In general, a fluoride such as BF
3
or NF
3
, a chloride such as BCl
3
or SnCl
4
, a bromide such as HBr, or the like is used as a treating gas for various treatments in the manufacturing process of semiconductors, liquid crystal devices and the like, so that there is a problem that parts in the treating vessel are considerably corroded and damaged.
For instance, as a material used in the plasma-treating vessel for the semiconductor manufacturing apparatus, there are known a metallic material such as Al, Al alloy or the like, an anodized oxide film of Al covering the surface of the metallic material, a sprayed coating such as boron carbide or the like, a sintered body film of Al
2
O
3
, Si
3
N
4
or the like, and a high polymer film of fluorine resin, epoxy resin or the like. These materials are known to be subjected to a chemical damage when being contacted with a halogen ion indicating a strong corrosive property, or to an erosion damage through fines particles of SiO
2
and Si
3
N
4
and an ion excited by a plasma.
Especially, a plasma is frequently used for more activating the reaction in the process using a halogen compound. However, the halogen compound is dissociated to atomic F, Cl, Br, I or the like indicating a very strong corrosive property under an environment using such a plasma. Even in this case, if a finely divided solid of SiO
2
, Si
3
N
4
, Si, W or the like is existent in such an environment, the member used in the plasma-treating vessel is strongly subjected to not only the chemical corrosion but also the erosion damage through the above fine particles.
And also, the environment excited by the plasma is ionized even by a gas having no corrosive property such as Ar gas to cause a phenomenon of strongly impinging to a solid face (ion bombardment), so that various members arranged in the above vessel are subjected to a stronger damage.
Heretofore, there was a method of forming a thin Al
2
O
3
film or the like as a technique adopted when being subjected to such a chemical corrosion or erosion damage. However, such a technique has the following problems.
(1) With respect to a material covered with Al
2
O
3
film (alumite) by subjecting Al and Al alloy to an anodization to provide corrosion resistance, there is a problem that the service life becomes shorter when being subjected to plasma erosion in an environment containing a halogen gas. And also, since it is an Al-containing film, AlF
3
particles are created, which bring about a fear of degrading quality of semiconductor product manufactured.
(2) There is a technique that a dense film of oxide, carbide, nitride, fluoride or the like of Group 3a element in the Periodic Table such as Sc, Y, La, Ce, Yb, Eu, Dy or the like is formed on the surface of a part through PVD or CVD process, or a single crystal of Y
2
O
3
is applied thereto (JP-A-10-4083). However, this technique has problems that the film forming rate is slow and the productivity is poor and plural film members (composite film) can not simultaneously be formed.
It is, therefore, an object of the invention to propose a surface-treated member for plasma-treating vessel or the like having large resistances to damage due to chemical corrosion and damage through plasma erosion under environment containing a halogen gas as well as a method of producing the same.
DISCLOSURE OF THE INVENTION
The invention solves the aforementioned problems and drawbacks of the conventional techniques by adopting means as mentioned below. That is, the construction of the invention is as follows:
(1) A cover member comprising a substrate and a layer of Y
2
O
3
sprayed coating having a porosity of 0.2-10% and a thickness of 50-2000 &mgr;m formed on a surface of the substrate through a thermal spraying process.
(2) A cover member comprising a substrate, and a composite layer consisting of a coating of one or more metals or alloys selected from Ni and an alloy thereof, W and an alloy thereof, Mo and an alloy thereof and Ti and an alloy thereof, which are excellent in an adhesion property to Y
2
O
3
sprayed coating, formed at a thickness of 50-500 &mgr;m as an undercoat on a surface of the substrate under a plasma generating condition in an environment containing a halogen compound through, preferably, a thermal spraying process and a Y
2
O
3
sprayed coating formed at a thickness of 50-2000 &mgr;m on the undercoat in case of an environment having a strong corrosion property.
(3) A cover member comprising a substrate and a multilayer composite layer consisting of the above metal coating (preferably sprayed coating) formed on a surface of the substrate as an undercoat, a Al
2
O
3
coating (preferably sprayed coating) formed on the undercoat as a middle layer and the above Y
2
O
3
sprayed coating formed on the middle layer as a topcoat through thermal spraying in case of an environment having a strong corrosion property.
(4) A cover member comprising a substrate and a multilayer composite layer consisting of the above metal coating (preferably sprayed coating) formed on a surface of the substrate as an undercoat, a film of Al
2
O
3
and Y
2
O
3
(preferably sprayed coating) formed on the undercoat as a middle layer and the above Y
2
O
3
sprayed coating formed on the middle layer as a topcoat through thermal spraying in case of an environment having a strong corrosion property.
(5) A cover member is covered with the Y
2
O
3
sprayed coating directly formed on the surface of the substrate or indirectly formed through the undercoat or middle layer in the above method, wherein the sprayed coating is obtained by using Y
2
O
3
powder having a purity of not less than 95% and adopting a spraying method selected from plasma-spraying the powder in air, plasma-spraying in an Ar gas containing no oxygen under a reduced pressure, high-speed flame spraying, explosion spraying and the like.
Among them, the method of plasma-spraying under the reduced pressure of Ar gas is also effective for the improvement of the corrosion resistance.
The present invention relates to an internal member for a plasma treating vessel comprising a substrate and a Y
2
O
3
sprayed coating covered on a surface thereof.
The present invention also relates to an internal member for a plasma treating vessel comprising a substrate, a metal coating formed on a surface thereof as an undercoat, and a Y
2
O
3
sprayed coating formed on the undercoat as a top coat.
The present invention also relates to an internal member for a plasma treating vessel comprising a substrate, a metal coating formed on a surface thereof as an undercoat, a middle layer formed on the undercoat and a Y
2
O
3
sprayed coating formed on the middle layer as a top coat.
The present invention also relates to a method of producing an internal member for a plasma treating vessel, which comprises covering Y
2
O
3
on a surface of a substrate through a spraying process to form a Y
2
O
3
sprayed coating, the Y
2
O
3
in the sprayed coating having a purity of not less than 95%.
The present invention also relates to a method of producing an internal member for a plasma treating vessel, which comprises applying at least one surface treating process selected from CVD process, PVD process and thermal spraying process to a surface of a substrate to form a composite layer composed of a layer of a metal of Ni, W, Mo or Ti or an alloy thereof as an undercoat and Y
2
O
3
as a top coat.
The pre
Hamaguchi Tatsuya
Harada Yoshio
Mitsuhashi Kouji
Nagayama Nobuyuki
Takeuchi Jun-ichi
Greenblum & Bernstein P.L.C.
Jones Deborah
Savage Jason
Tocalo Co., Ltd.
LandOfFree
Plasma processing container internal member and production... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Plasma processing container internal member and production..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Plasma processing container internal member and production... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3298092