Patents Assigned to NIKKA SEIKO CO., LTD.
  • Patent number: 11608433
    Abstract: A formulation for a wafer dicing process comprises 1.0 to 1.5 mass % of a partially saponified polyvinyl alcohol having a polymerization degree of 200 to 400 and a saponification degree of 75 to 85 mol %; 0.4 to 0.6 mass % of polyoxyethylene-polyoxypropylene glycol ether having a number average molecular weight of 10,000 to 20,000 with a polymerization ratio of polyoxyethylene to polyoxypropylene of 75:25 to 85:15; and pure water (all mass % based on 100 mass % of formulation). The formulation is used in the form of a processing solution obtained by diluting it 10,000 to 100,000 times by pure water and flowing it on a dicing blade in a wafer dicing process to effectively remove dicing offcuts from the wafer and minute pieces of adhesive released from an adhesive layer of a dicing tape.
    Type: Grant
    Filed: August 16, 2019
    Date of Patent: March 21, 2023
    Assignee: NIKKA SEIKO CO., LTD.
    Inventors: Tsuyoshi Tadano, Masafumi Hirose, Yuta Akutsu
  • Patent number: 10700016
    Abstract: A protective film material for laser processing comprises a solution of a water-soluble adhesive and a water-soluble laser beam absorbent added to adjust absorbance at a wavelength of 355 nm (absorbance as calculated as a 200-times diluted solution) to 0.3 to 3. The protective film effectively absorbs an irradiated laser beam, reduces generation of debris during laser beam irradiation, and can be removed by washing with water after completion of the laser processing treatment, thereby providing reliable processing. The water-soluble adhesive is preferably a blend of polyvinyl alcohol and poly-N-vinyl acetamide, which are preferably blended at a ratio of 100 to 200:1 in terms of amounts of respective components.
    Type: Grant
    Filed: June 18, 2018
    Date of Patent: June 30, 2020
    Assignee: NIKKA SEIKO CO., LTD.
    Inventors: Tsuyoshi Tadano, Masafumi Hirose, Daisuke Tomita
  • Patent number: 9502295
    Abstract: A protective film material for protecting a surface of a wafer during a laser processing treatment contains a water soluble poly-N-vinyl acetamide. The protective film material is applied to the surface of the wafer which is then irradiated with a laser beam through the protective film material to perform a laser processing treatment. After the laser processing treatment, the protective film material is removed by washing with water.
    Type: Grant
    Filed: December 15, 2014
    Date of Patent: November 22, 2016
    Assignee: NIKKA SEIKO CO., LTD.
    Inventors: Masaaki Shinjo, Yoshimasa Takeuchi, Tsuyoshi Tadano, Masafumi Hirose