Patents by Inventor Daijitsu Harada

Daijitsu Harada has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9505166
    Abstract: A rectangular substrate is used as a mold after it is provided with a topological pattern. The substrate has A-side and B-side opposed surfaces, the A-side surface being provided with the topological pattern. The A-side surface includes a central rectangular region of 1 to 50 mm by 1 to 50 mm having a flatness of up to 350 nm. Use of the mold-forming substrate prevents the occurrence of a pattern misalignment or pattern error between the step of forming a pattern on a mold-forming substrate and the transfer step. Transfer of a fine size and complex pattern is possible.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: November 29, 2016
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Daijitsu Harada, Daiyu Okafuji, Hiroyuki Yamazaki, Masaki Takeuchi
  • Publication number: 20160332280
    Abstract: Proposed herein is a method for producing substrates, particularly those of synthetic quartz glass, while saving the substrate surface from killer defects without resorting to any large-scale apparatus and precision polishing plate, thereby reducing defectives and improving yields more than in production with conventional facilities. The method for producing substrates by polishing, includes steps of placing substrate stocks individually in work holes formed in a carrier on a lower polishing plate, bringing an upper polishing plate into contact with the surface of the substrate stocks, with the surface of the substrate stocks being coated with an impact-absorbing liquid and the lower polishing plate being rotated, and rotating the upper and lower polishing plates, with the surface of the substrate stocks being accompanied by a polishing slurry.
    Type: Application
    Filed: May 12, 2016
    Publication date: November 17, 2016
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Harunobu MATSUI, Daijitsu HARADA, Masaki TAKEUCHI
  • Patent number: 9487426
    Abstract: A method for heat treating a synthetic quartz glass having a hydroxyl concentration with a maximum/minimum difference (?OH) of less than 350 ppm involves the steps of first heat treatment of holding at 1,150-1,060° C. for a time of 0.5-10 hours, cooling down to a second heat treatment temperature at a rate of ?7° C./hr to ?30° C./hr, second heat treatment of holding at 1,030-950° C. for a time of 5-20 hours, and annealing at a rate of ?25° C./hr to ?85° C./hr. Two stages of heat treatment ensures that the glass has a low birefringence.
    Type: Grant
    Filed: February 13, 2015
    Date of Patent: November 8, 2016
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Hisashi Yagi, Masaki Takeuchi, Daijitsu Harada
  • Patent number: 9316902
    Abstract: 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 ?m.
    Type: Grant
    Filed: September 6, 2013
    Date of Patent: April 19, 2016
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Daijitsu Harada, Mamoru Morikawa, Masaki Takeuchi, Yukio Shibano
  • Patent number: 9309447
    Abstract: A method for recovery of cerium oxide from the abrasive waste composed mainly of cerium oxide arising from the polishing of glass substrates, said method including the steps of (i) adding to the abrasive waste an aqueous solution of a basic substance; (ii) adding to the resulting solution a precipitant, thereby forming precipitates composed mainly of cerium oxide, and removing the supernatant liquid; (iii) adding to the resulting precipitates a solution of an acid substance, thereby making said precipitate slightly acid to neutral; (iv) washing the precipitates with an organic solvent; and (v) drying and crushing the precipitates. The method males it possible to recycle abrasive waste into a pure abrasive composed mainly of cerium oxide which can be reused to polish synthetic quartz glass substrates for state-of-the-art semiconductor technology relating to photomasks and reticles.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: April 12, 2016
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Harunobu Matsui, Daijitsu Harada, Masaki Takeuchi
  • Publication number: 20150360997
    Abstract: A synthetic quartz glass substrate is prepared by furnishing a synthetic quartz glass block, coating an arbitrary surface and an opposite surface of the block with a liquid having a transmittance of at least 99.0%/mm at the wavelength of birefringence measurement, measuring the birefringence of the block by letting light enter one coated surface and exit the other coated surface, and sorting the block to an acceptable or unacceptable group, based on the measured birefringence value.
    Type: Application
    Filed: June 11, 2015
    Publication date: December 17, 2015
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Daijitsu Harada, Kazuo Shirota, Hisashi Yagi, Masaki Takeuchi
  • Publication number: 20150239766
    Abstract: A method for heat treating a synthetic quartz glass having a hydroxyl concentration with a maximum/minimum difference (?OH) of less than 350 ppm involves the steps of first heat treatment of holding at 1,150-1,060° C. for a time of 0.5-10 hours, cooling down to a second heat treatment temperature at a rate of ?7° C./hr to ?30° C./hr, second heat treatment of holding at 1,030-950° C. for a time of 5-20 hours, and annealing at a rate of ?25° C./hr to ?85° C./hr. Two stages of heat treatment ensures that the glass has a low birefringence.
    Type: Application
    Filed: February 13, 2015
    Publication date: August 27, 2015
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Hisashi Yagi, Masaki Takeuchi, Daijitsu Harada
  • Patent number: 9090502
    Abstract: A nanoimprint-mold release agent including an alkoxysilane compound represented by general formula (1) is provided wherein Rf and Rf? are each independently a fluoroalkyl group of 1 to 10 carbon atoms; R1 is a hydrogen atom or an aliphatic monovalent hydrocarbon group of 1 to 6 carbon atoms; R2 and R3 are each independently methyl group or ethyl group; X and Y are each independently an ether linkage or an ester linkage; a and b are each 0 or 1; m, n, and p are each an integer of 0 to 6; q is an integer of 1 to 6 and r is an integer of 0 to 2.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: July 28, 2015
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Hiroyuki Yamazaki, Daijitsu Harada, Masaki Takeuchi, Takayuki Honma, Ayumu Kiyomori, Tohru Kubota
  • Publication number: 20150202731
    Abstract: A synthetic quartz glass substrate is prepared by immersing a starting substrate in an aqueous solution of a nonionic surfactant and precision polishing the substrate with a colloidal silica water dispersion. A synthetic quartz glass substrate having a few defects and low surface roughness is obtained while the polishing rate is improved and the polishing time is reduced.
    Type: Application
    Filed: January 15, 2015
    Publication date: July 23, 2015
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Harunobu Matsui, Daijitsu Harada, Masaki Takeuchi
  • Publication number: 20150021292
    Abstract: 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.
    Type: Application
    Filed: October 9, 2014
    Publication date: January 22, 2015
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Daijitsu HARADA, Masaki TAKEUCHI, Yukio SHIBANO, Shuhei UEDA, Atsushi WATABE
  • Patent number: 8927754
    Abstract: Disclosed are silazane compounds having two fluoroalkyl groups, represented by the following general formula (1): wherein Rf and Rf? are each a fluoroalkyl group, R1 is a hydrogen atoms or an aliphatic monovalent hydrocarbon group, R2 and R3 are each an aliphatic monovalent hydrocarbon group, R4 is a hydrogen atom or an aliphatic monovalent hydrocarbon group, a and b are each 0 or 1, m, n and p are each an integer of 0 to 6, q is an integer of 1 to 6, and r is 1 or 2. By treating an inorganic material with the silazane compound having two fluoroalkyl groups, high water and oil repellency and high sliding properties can be imparted to the inorganic material in good balance.
    Type: Grant
    Filed: April 12, 2012
    Date of Patent: January 6, 2015
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Takayuki Honma, Ayumu Kiyomori, Tohru Kubota, Daijitsu Harada, Hiroyuki Yamazaki, Masaki Takeuchi
  • Publication number: 20140295738
    Abstract: A polishing composition comprising a colloidal dispersion of spherical silica particles and associated silica particles as abrasive is provided. When used in the step of polishing synthetic quartz glass substrates, the polishing composition ensures a higher polishing rate than conventional colloidal silica and is effective for preventing any microscopic defects on the substrate surface, thus providing the substrate with a high smoothness. The polishing composition can be used as the ceria replacement polishing composition for polishing a lapped surface.
    Type: Application
    Filed: March 24, 2014
    Publication date: October 2, 2014
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Harunobu Matsui, Daijitsu Harada, Masaki Takeuchi
  • Publication number: 20140242884
    Abstract: A polishing slurry comprising a collagen derivative and a colloidal solution is effective for polishing of synthetic quartz glass substrates. It prevents formation of defects having a size that can be detected by a high-sensitivity flaw detector.
    Type: Application
    Filed: May 5, 2014
    Publication date: August 28, 2014
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Harunobu MATSUI, Daijitsu HARADA, Masaki TAKEUCHI
  • Publication number: 20140120198
    Abstract: A rectangular substrate is used as a mold after it is provided with a topological pattern. The substrate has A-side and B-side opposed surfaces, the A-side surface being provided with the topological pattern. The A-side surface includes a central rectangular region of 1 to 50 mm by 1 to 50 mm having a flatness of up to 350 nm. Use of the mold-forming substrate prevents the occurrence of a pattern misalignment or pattern error between the step of forming a pattern on a mold-forming substrate and the transfer step. Transfer of a fine size and complex pattern is possible.
    Type: Application
    Filed: October 31, 2013
    Publication date: May 1, 2014
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Daijitsu HARADA, Daiyu OKAFUJI, Hiroyuki YAMAZAKI, Masaki TAKEUCHI
  • Publication number: 20140004309
    Abstract: 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 ?m.
    Type: Application
    Filed: September 6, 2013
    Publication date: January 2, 2014
    Applicant: SHIN-ETSI CHEMICAL CO., LTD.
    Inventors: Daijitsu HARADA, Mamoru MORIKAWA, Masaki TAKEUCHI, Yukio SHIBANO
  • Patent number: 8551346
    Abstract: 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 ?m.
    Type: Grant
    Filed: December 10, 2010
    Date of Patent: October 8, 2013
    Assignee: Shin-Etsu Chemcial Co., Ltd.
    Inventors: Daijitsu Harada, Mamoru Morikawa, Masaki Takeuchi, Yukio Shibano
  • Patent number: 8536359
    Abstract: Disclosed are alkoxysilane compounds having two fluoroalkyl groups and represented by the following general formula (1): wherein Rf and Rf? are each a fluoroalkyl group of 1 to 10 carbon atoms, R1 is a hydrogen atom or an aliphatic monovalent hydrocarbon group of 1 to 6 carbon atoms, R2 and R3 are each methyl group or ethyl group, X and Y are each an ether linkage or an ester linkage, a and b are each 0 or 1, m, n and p are each an integer of 0 to 6, q is an integer of 1 to 6, and r is an integer of 0 to 2. By treating an inorganic material with the alkoxysilane compound having ether linkage and two fluoroalkyl groups, high water and oil repellency and high sliding properties can be imparted to the inorganic material. The alkoxysilane compounds can be easily purified, owing to enhancement of volatility by the branched structure.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: September 17, 2013
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Takayuki Honma, Ayumu Kiyomori, Tohru Kubota, Daijitsu Harada, Hiroyuki Yamazaki, Masaki Takeuchi
  • Patent number: 8500517
    Abstract: A synthetic quartz glass substrate is prepared by (1) polishing a synthetic quartz glass substrate with a polishing slurry comprising colloidal particles, an ionic organic compound having an electric charge of the same type as the colloidal particles, and water, and (2) immersing the polished substrate in an acidic or basic solution for etching the substrate surface to a depth of 0.001-1 nm. The method produces a synthetic quartz glass substrate while preventing formation of defects of a size that is detectable by the high-sensitivity defect inspection tool, and providing the substrate with a satisfactory surface roughness.
    Type: Grant
    Filed: December 13, 2010
    Date of Patent: August 6, 2013
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Daijitsu Harada, Masaki Takeuchi
  • Patent number: 8360824
    Abstract: Disclosed is a method of processing a synthetic quartz glass substrate for a semiconductor, wherein a polishing part of a rotary small-sized processing tool is put in contact with a surface of the synthetic quartz glass substrate in a contact area of 1 to 500 mm2, and is scanningly moved on the substrate surface while being rotated so as to polish the substrate surface. When the method is applied to the production of a synthetic quartz glass such as one for a photomask substrate for use in photolithography which is important to the manufacture of ICs or the like, a substrate having an extremely excellent flatness and capable of being used even with the EUV lithography can be obtained comparatively easily and inexpensively.
    Type: Grant
    Filed: January 26, 2010
    Date of Patent: January 29, 2013
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Daijitsu Harada, Masaki Takeuchi, Harunobu Matsui
  • Publication number: 20120263816
    Abstract: A nanoimprint-mold release agent including an alkoxysilane compound represented by general formula (1) is provided wherein Rf and Rf? are each independently a fluoroalkyl group of 1 to 10 carbon atoms; R1 is a hydrogen atom or an aliphatic monovalent hydrocarbon group of 1 to 6 carbon atoms; R2 and R3 are each independently methyl group or ethyl group; X and Y are each independently an ether linkage or an ester linkage; a and b are each 0 or 1; m, n, and p are each an integer of 0 to 6; q is an integer of 1 to 6 and r is an integer of 0 to 2.
    Type: Application
    Filed: April 11, 2012
    Publication date: October 18, 2012
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Hiroyuki Yamazaki, Daijitsu Harada, Masaki Takeuchi, Takayuki Honma, Ayumu Kiyomori, Tohru Kubota