Shin-etsu Chemical Co., Ltd.

Yukio Shibano

Atsushi Watabe

Masaki Takeuchi

Shuhei Ueda

Daijitsu Harada

Daisuke Kusabiraki

Masaki Tabata

Mamoru Morikawa

Satoru Miharada

Hisatoshi Otsuka

Tetsushi Tsukamoto

Toshinari Murai

Disclosed is a polishing agent for synthetic quartz glass substrates, which is characterized by containing a colloidal solution of a colloidal silica or the like having a colloid concentration of 20-50% by mass, and a polycarboxylic acid polymer, an acidic amino acid, a phenol or a glycosaminoglycan.

Polishing agent for synthetic quartz glass substrate

A photomask-forming glass substrate having a square major surface is provided wherein two strip regions are defined on the major surface near a pair of opposed sides such that each region spans between 2 mm and 10 mm inward of the side and excludes end portions extending 2 mm inward from the opposed ends of the side, a least squares plane is computed for each of the two strip regions, the angle included between normal lines to the least squares planes of two strip regions is within 10 seconds, and the height difference between two strip regions is up to 0.5 &#x3bc;m.

Photomask-forming glass substrate and making method

A large-size synthetic quartz glass substrate is produced by measuring a flatness and parallelism of front and back surfaces of a synthetic quartz glass substrate stock having a diagonal length of at least 1,000 mm, and partially removing raised portions and thick portions of the substrate stock on the basis of the measured data of flatness and parallelism. The removing step includes abrasive working by a first working tool having a diameter of 15-50% of the diagonal length, and abrasive working by a second working tool having a smaller diameter.

Method for producing large-size synthetic quartz glass substrate

A large-size substrate adapted for light exposure is of a plate shape having a diagonal length or diameter of 500-2,000 mm, a thickness of 1-20 mm, and a peripheral surface with a roughness Ra of 0.05-0.4 &#x3bc;m. The number of particles released from the substrate periphery during cleaning is minimized, leading to an improved yield in the cleaning step. The substrate can be manually handled, achieving an improvement in substrate quality without a need for a handling mechanism.

Large-size substrate

A used large-size photomask substrate having a patterned light-shielding film is recycled by (i) removing the light-shielding film from the used substrate to provide a photomask-forming glass substrate stock, (ii) resurfacing the glass substrate stock by sand blasting, (iii) repolishing the resurfaced glass substrate stock to yield a regenerated glass substrate stock, (iv) applying a light-shielding film onto the regenerated glass substrate stock to yield a regenerated photomask-forming blank, and (v) processing the light-shielding film of the blank into a pattern corresponding to a desired exposure of a mother glass, yielding a regenerated photomask substrate.

Recycling of large-size photomask substrate

A large-sized substrate having a diagonal length of not less than 500 mm and a ratio of flatness/diagonal length of not more than 6&#xd7;10is disclosed. By use of the large-sized substrate for exposure of the present invention, the exposure accuracy, particularly the register accuracy and resolution are enhanced, so that it is possible to achieve high-precision exposure of a large-sized panel. With the processing method according to the present invention, it is possible to stably obtain a large-sized photomask substrate with a high flatness, and since the CD accuracy (dimensional accuracy) at the time of exposure of the panel is enhanced, it is possible to perform exposure of a fine pattern, leading to a higher yield of the panel. Furthermore, by applying the processing method according to the present invention, it is also possible to create an arbitrary surface shape.

Large-sized glass substrate

A large-size glass substrate, from which a photomask substrate is formed, is prepared by processing a large-size glass substrate stock by (1) a flattening removal quantity based on height data of the substrate stock in the vertical attitude plus a deformation-corrective removal quantity. The deformation-corrective removal quantity is calculated from (2) a deflection of the substrate stock by its own weight in the horizontal attitude, (3) a deformation of the photomask substrate caused by chucking in an exposure apparatus, and (4) an accuracy distortion of a platen for supporting a mother glass.

Large-size glass substrate for photomask and making method, computer-readable recording medium, and mother glass exposure method

A wafer substrate is polished by disposing the wafer substrate between an abrasive cloth on a polishing platen and a plate, and relatively rotating the polishing platen and the plate for mirror polishing the surface of the wafer substrate with the abrasive cloth. A liquid is fed onto the plate side surface of the wafer substrate so that the wafer substrate is directly held to the plate by the adsorption force of the liquid, while performing the mirror polishing.

Wafer polishing method and polished wafer

A large-sized substrate having a diagonal length of not less than 500 mm and a ratio of flatness/diagonal length of not more than 6.0&#xd7;10is disclosed. By use of the large-sized substrate for exposure of the present invention, the exposure accuracy, particularly the register accuracy and resolution are enhanced, so that it is possible to achieve high-precision exposure of a large-sized panel. With the processing method according to the present invention, it is possible to stably obtain a large-sized photomask substrate with a high flatness, and since the CD accuracy (dimensional accuracy) at the time of exposure of the panel is enhanced, it is possible to perform exposure of a fine pattern, leading to a higher yield of the panel. Furthermore, by applying the processing method according to the present invention, it is also possible to create an arbitrary surface shape.

Large-sized substrate and method of producing the same

A large-size substrate having improved flatness is prepared by measuring the flatness of one surface or opposite surfaces of a large-size substrate having a diagonal length of at least 500 mm, and partially removing raised portions on the one surface or opposite surfaces of the substrate by means of a processing tool on the basis of the measured data. The processing tool is adapted to blast a slurry of microparticulates in water carried on compressed air against the substrate.

Method for preparing large-size substrate

A silica glass substrate is obtained by polishing, cleaning, drying and etching a silica glass substrate slice. When the substrate on one surface is treated with a reactive reagent, defects having a size of at least 0.3 &#x3bc;m in a direction parallel to the substrate major surface are absent on the substrate surface. The silica glass substrate, in which no submicron defects manifest on the substrate surface even when treated as by cleaning or etching, serves as a reticle for use in photolithographic IC fabrication, achieving an improved manufacturing yield in the semiconductor device fabrication and microelectronic system fields.

Silica glass substrates and their selection

A glass substrate is to be used as a photomask having a patterned light-shielding film on a surface thereof and thus exposed to light. The substrate is leveled by local plasma etching such that an exposure surface may have a flatness of 0.04-2.2 nm/cm. Since the glass substrate is configured such that the exposure surface or hold surface of the resulting photomask is fully flat during the exposure step, it is suited for use as silica glass substrates for photomasks used in the photolithography of great interest in the fabrication of ICs, thus contributing to the achievement of finer patterns in the semiconductor field.

Glass substrate for photomasks and preparation method

A glass substrate having a surface which has been leveled, preferably to a flatness of 0.04-1.3 nm/cmof the surface, by local plasma etching is provided. A glass substrate whose surface carries microscopic peaks and valleys is leveled by measuring the height of peaks and valleys on the substrate surface, and plasma etching the substrate surface while controlling the amount of plasma etching in accordance with the height of peaks.

Glass substrate and leveling thereof

A synthetic quartz glass substrate is prepared by annealing a synthetic quartz glass member having a higher hydroxyl content in a peripheral portion than in a central portion, machining off the peripheral portion of the member, slicing the member into a plate shaped substrate, chamfering and etching the substrate. The synthetic quartz glass substrate has a minimized birefringence and is suited for use as a photomask in photolithography.

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Joetsu, Japan

Yukio Shibano