Abstract: Provided is a silica glass disc in which the deformation amount thereof in heat treatment is minimized, and the surface area of a silica glass surface can be increased. There is provided a silica glass disc, including a dimple forming area in which a large number of dimples are formed on at least one of a front surface or a back surface of a silica glass body, and the dimples in the dimple forming area are regularly formed. It is preferred that the dimples be formed by a laser.

Abstract: Provided is a doped quartz glass member for plasma etching, which is used in a plasma etching process and is free from any problematic fluoride accumulation during use. The quartz glass member for plasma etching is used as a jig for semiconductor production in a plasma etching process, and includes at least two or more kinds of metal elements in a total amount of 0.01 wt % or more to less than 0.1 wt %, in which the metal elements are formed of at least one kind of a first metal element selected from metal elements belonging to Group 3B of the periodic table and at least one kind of a second metal element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, lanthanoids, and actinoids.

Abstract: A member for a plasma etching device, comprising a coating film of yttrium oxide or YAG having a coating film thickness of 10 ?m or more, a coating film thickness variance of 15% or less, preferably a surface roughness (Ra) of 1 ?m or less, formed on a surface of a member, comprising quartz glass which contains 1 to 10% by weight of yttrium oxide or YAG. The member for a plasma etching device has high plasma resistance, is not subjected to an abnormal etching on the basis of a partial change of electric properties and, accordingly, can be used for a long period of time. Even when the member is large enough to handle 12-inch Si wafers, the above-described advantageous properties are maintained and the member can be used for a long period of time.

Abstract: A member for a plasma etching device, which comprises a device substrate comprising quartz glass, aluminum, alumite or a combination thereof and, formed on the surface thereof, a coating film of yttrium oxide or YAG having a film thickness of 10 ?m or more and a variation in the thickness of 10% or less, and preferably a surface roughness (Ra) of 1 ?m or less; and a method for manufacturing the member for a plasma etching device, which comprises a step of plasma-spraying yttrium oxide or YAG to the surface of said device substrate or a step of fusing yttrium oxide or YAG with an oxyhydrogen flame, followed by coating the surface with the fused product, or a step of applying a solution containing yttrium, a yttrium compound or YAG on the above surface, followed by heating to fuse the resultant coating, or a combination of the above steps, thereby forming a coating film of yttrium oxide or YAG having a film thickness 10 ?m or more and a variation in the thickness of 10% or less, and preferably a surface roughne

Abstract: A member for a plasma etching device, which comprises a device substrate comprising quartz glass, aluminum, alumite or a combination thereof and, formed on the surface thereof, a coating film of yttrium oxide or YAG having a film thickness of 10 ?m or more and a variation in the thickness of 10% or less, and preferably a surface roughness (Ra) of 1 ?m or less; and a method for manufacturing the member for a plasma etching device, which comprises a step of plasma-spraying yttrium oxide or YAG to the surface of said device substrate or a step of fusing yttrium oxide or YAG with an oxyhydrogen flame, followed by coating the surface with the fused product, or a step of applying a solution containing yttrium, a yttrium compound or YAG on the above surface, followed by heating to fuse the resultant coating, or a combination of the above steps, thereby forming a coating film of yttrium oxide or YAG having a film thickness 10 ?m or more and a variation in the thickness of 10% or less, and preferably a surface roughne

Abstract: An object of the present invention is to provide a quartz glass body, especially a quartz glass jig for plasma reaction in producing semiconductors having excellent resistance against plasma corrosion, particularly, excellent corrosion resistance against F-based gaseous plasma; and a method for producing the same. A body made of quartz glass containing a metallic element and having an improved resistance against plasma corrosion is provided that contains bubbles and crystalline phase at an amount expressed by projected area of less than 100 mm2 per 100 cm3.

Abstract: An object of the present invention is to provide a quartz glass jig, which, when employed in a processing apparatus using plasma, is less in generation of abnormal etching and particles and low in contamination with impurities. This object is obtained by a quartz glass jig for a processing apparatus using plasma, wherein a surface of the jig is subjected to grinding or a sandblast processing and has a surface roughness Ra in the range of from 2 ?m to 0.05 ?m, and microcracks of grinding marks formed during the grinding or sandblast processing have a depth of 50 ?m or less.

Abstract: An object of the present invention is to provide a fluororesin-coated quartz glass jig free from peeling off of fluororesin coating on using hydrofluoric acid or from generating particles due to the etching of quartz glass, while yet preventing the generation of chipping by relaxing the impact imposed on the quartz glass by silicon wafers. It also is an object of the present invention to provide a production method of the fluororesin-coated quartz glass jig. The object above is achieved by a fluororesin-coated quartz glass jig the surface thereof is wholly covered with a pinhole-free fluororesin coating, and by a method for producing the same.

Abstract: A silica glass jig for semiconductor industry, characterized by having, on the surface of the jig, pyramidal projected structures with their cut-off apices and concave portions provided therebetween, and small projections are uniformly distributed thereon; the silica glass jig has a surface with many dimple-form concave portions each having a width of from 20 to 300 &mgr;m exist and there are grooves each having a width of from 0.5 to 50 &mgr;m at an interval of from 20 to 300 &mgr;m, and small projections each having a width of from 1 to 50 &mgr;m and having a height of from 0.1 to 10 &mgr;m are uniformly distributed between the grooves and in the grooves.

Abstract: An object of the present invention is to provide a quartz glass tank for use in ultrasonic cleaning that can be used for a long time without causing etching or layer peeling of the quartz glass and a method for producing the same.

Abstract: It is an object of the present invention to provide a quartz glass jig excellent in the plasma etching resistant characteristics, which does not generate an abnormal etching and particles when used for a plasma generating apparatus. The above Object is obtained by a plasma resistant quartz glass jig that is used for an apparatus of generating plasma, wherein the surface roughness Ra of the quartz glass surface is in a range of from 5 &mgr;m to 0.05 &mgr;m, the number of microcracks of the surface is not more than 500 microcracks/cm2, and the hydrogen molecule concentration in the quartz glass is at least 5×1016 molecules/cm3.

Abstract: An object of the present invention is to provide a quartz glass jig, which, when employed in a processing apparatus using plasma, is less in generation of abnormal etching and particles and low in contamination with impurities. This object is obtained by a quartz glass jig for a processing apparatus using plasma, wherein a surface of the jig is subjected to grinding or a sandblast processing and has a surface roughness Ra in the range of from 2 &mgr;m to 0.05 &mgr;m, and microcracks of grinding marks formed during the grinding or sandblast processing have a depth of 50 &mgr;m or less.

Abstract: A quartz glass member for use in dry etching, wherein at least the inner surface of the member to be brought into contact with plasma is constructed of synthetic quartz glass, and a dry etching system equipped with the same member. A dry etching system equipped with the quartz glass member, which minimizes the generation of particles and which prevent a drop in electrical characteristics from occurring on the silicon wafer.

Abstract: A quartz glass jig having large irregularities on the surface thereof, wherein said irregularities have a center line roughness Ra in the range of from 2 to 30 &mgr;m, a maximum height Rmax in the range of from 10 to 150 &mgr;m, and a width in the range of from 10 to 500 &mgr;m, and by a method which comprises forming an inorganic thin film on the surface of a quartz glass jig free from microcracks and having fine irregularities on the surface thereof and thereafter rinsing it a plurality of times.

Abstract: An object of the present invention is to provide a fluororesin-coated quartz glass jig free from peeling off of fluororesin coating on using hydrofluoric acid or from generating particles due to the etching of quartz glass, while yet preventing the generation of chipping by relaxing the impact imposed on the quartz glass by silicon wafers. It also is an object of the present invention to provide a production method of the fluororesin-coated quartz glass jig. The object above is achieved by a fluororesin-coated quartz glass jig the surface thereof is wholly covered with a pinhole-free fluororesin coating, and by a method for producing the same.

Abstract: A silica glass jig for semiconductor industry, which is does not contaminate semiconductor elements, and generates less cracks and a production method thereof are provided.

Abstract: An object of the present invention is to provide a quartz glass body, especially a quartz glass jig for plasma reaction in producing semiconductors having excellent resistance against plasma corrosion, particularly, excellent corrosion resistance against F-based gaseous plasma; and a method for producing the same. A body made of quartz glass containing a metallic element and having an improved resistance against plasma corrosion is provided that contains bubbles and crystalline phase at an amount expressed by projected area of less than 100 mm2 per 100 cm3.

Abstract: It is an object of the present invention to provide a quartz glass jig excellent in the plasma etching resistant characteristics, which does not generate an abnormal etching and particles when used for a plasma generating apparatus.

Abstract: Opaque silica glass having a density of 2.0 to 2.18 g/cm.sup.3, sodium and potassium elements concentrations in the silica glass of each 0.5 ppm or less and an OH group concentration of 30 ppm or less, and containing bubbles which are independent bubbles having the following physical values: a bubble diameter of 300 .mu.m or less, and a bubble density of 100,000 to 1,000,000 bubbles/cm.sup.3, and a production process for opaque silica glass, including: filling quartz raw material grain having a particle size of 10 to 350 .mu.m in a heat resistant mold, heating it in a non-oxidizing atmosphere from a room temperature up to a temperature lower by 50 to 150.degree. C. than a temperature at which the above raw material grain is melted at a temperature-raising speed not exceeding 50.degree. C./minute, then, slowly heating it up to a temperature higher by 10 to 80.degree. C. than the temperature at which the quartz raw material grain is melted at the speed of 10.degree. C.

Abstract: An object of the present invention is to provide a quartz glass body, especially a quartz glass jig for plasma reaction in producing semiconductors having excellent resistance against plasma corrosion, particularly, excellent corrosion resistance against F-based gaseous plasma; and a method for producing the same. A body made of quartz glass containing a metallic element and having an improved resistance against plasma corrosion is provided that contains bubbles and crystalline phase at an amount expressed by projected area of less than 100 mm2 per 100 cm3.