Patents by Inventor Ershad Ali Chowdhury

Ershad Ali Chowdhury 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: 9061500
    Abstract: A method of manufacturing a printhead substrate, including forming a metal pattern, including a portion forming a pair of electrodes, on an insulating member, forming a conductive film which covers the insulating member and the metal pattern, including a first portion forming a temperature detection element and a second portion except for the first portion, etching the second portion so as to form the pair of electrodes, and etching the first portion so as to form the temperature detection element which is connected to the pair of electrodes, wherein an etching amount in the etching the second portion is larger than a thickness of the conductive film, and an etching amount in the etching the first portion is smaller than the etching amount in the etching the second portion.
    Type: Grant
    Filed: October 7, 2014
    Date of Patent: June 23, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ershad Ali Chowdhury, Takayuki Kimura, Kenji Makino
  • Publication number: 20150109370
    Abstract: A method of manufacturing a printhead substrate, including forming a metal pattern, including a portion forming a pair of electrodes, on an insulating member, forming a conductive film which covers the insulating member and the metal pattern, including a first portion forming a temperature detection element and a second portion except for the first portion, etching the second portion so as to form the pair of electrodes, and etching the first portion so as to form the temperature detection element which is connected to the pair of electrodes, wherein an etching amount in the etching the second portion is larger than a thickness of the conductive film, and an etching amount in the etching the first portion is smaller than the etching amount in the etching the second portion.
    Type: Application
    Filed: October 7, 2014
    Publication date: April 23, 2015
    Inventors: Ershad Ali Chowdhury, Takayuki Kimura, Kenji Makino
  • Patent number: 7270398
    Abstract: A circuit board for a liquid discharging apparatus in which coating performance of a protective layer and a cavitation resistive film on a heat generating element is excellent and durability is excellent and a manufacturing method of such a circuit board are provided. A surface portion of a wiring material layer is processed so that an etching speed of the surface portion is made higher than that of the material forming the wiring material layer. It is desirable to execute a process for forming at least one selected from a fluoride, a chloride, and a nitride of the material forming the wiring material layer into the surface portion of the wiring material layer.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: September 18, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiichi Sasaki, Masato Kamiichi, Ershad Ali Chowdhury, Yukihiro Hayakawa
  • Patent number: 7244370
    Abstract: In order to provide a circuit substrate with a satisfactory step coverage by the protective layer and the anti-cavitation film in an edge portion of wirings and a liquid discharge head utilizing such circuit substrate, the invention provides a method for producing a circuit substrate provided, on an insulating surface of a substrate, with a plurality of elements each including a resistive layer and a pair of electrodes formed with a predetermined spacing on said resistive layer, including a step of forming an aluminum electrode wiring layer on the resistive layer, a step of isolating the electrode wiring layer by dry etching into each element, and a step of forming the electrode wiring into a tapered cross section with an etching solution containing phosphoric acid, nitric acid and a chelating agent capable of forming a complex with the wiring metal.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: July 17, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiichi Sasaki, Masato Kamiichi, Yukihiro Hayakawa, Ershad Ali Chowdhury
  • Patent number: 6838351
    Abstract: A circuit board for a liquid discharging apparatus in which coating performance of a protective layer and a cavitation resistive film on a heat generating element is excellent and durability is excellent and a manufacturing method of such a circuit board are provided. A surface portion of a wiring material layer is processed so that an etching speed of the surface portion is made higher than that of the material forming the wiring material layer. It is desirable to execute a process for forming at least one selected from a fluoride, a chloride, and a nitride of the material forming the wiring material layer into the surface portion of the wiring material layer.
    Type: Grant
    Filed: March 22, 2004
    Date of Patent: January 4, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiichi Sasaki, Masato Kamiichi, Ershad Ali Chowdhury, Yukihiro Hayakawa
  • Publication number: 20040191982
    Abstract: A circuit board for a liquid discharging apparatus in which coating performance of a protective layer and a cavitation resistive film on a heat generating element is excellent and durability is excellent and a manufacturing method of such a circuit board are provided. A surface portion of a wiring material layer is processed so that an etching speed of the surface portion is made higher than that of the material forming the wiring material layer. It is desirable to execute a process for forming at least one selected from a fluoride, a chloride, and a nitride of the material forming the wiring material layer into the surface portion of the wiring material layer.
    Type: Application
    Filed: March 22, 2004
    Publication date: September 30, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Keiichi Sasaki, Masato Kamiichi, Ershad Ali Chowdhury, Yukihiro Hayakawa