Patents by Inventor Aya Nishiyama

Aya Nishiyama 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: 9871152
    Abstract: To provide a solar cell that reduces occurrence of a defect and has high photoelectric conversion efficiency. The solar cell includes a silicon substrate such as an n-type single-crystal silicon substrate single crystal with pyramid-shaped irregularities P formed thereon, and an amorphous or microcrystal semiconductor layer formed on the single-crystal silicon substrate. A flat part F is formed in a valley portion of the pyramid-shaped irregularities P provided on a surface of the single-crystal silicon substrate. With this configuration, a steep angle of 70° to 85° of a concave portion formed by a substantially (111) surface can be widened to between 115° and 135°. Accordingly, a change of atomic step morphology attributable to a rounded shape can be eliminated, thereby enabling to reduce epitaxial growth and defects in the amorphous or microcrystal semiconductor layer.
    Type: Grant
    Filed: October 15, 2012
    Date of Patent: January 16, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Aya Nishiyama, Hiroyuki Fuchigami, Hidetada Tokioka
  • Publication number: 20150068594
    Abstract: To provide a solar cell that reduces occurrence of a defect and has high photoelectric conversion efficiency. The solar cell includes a silicon substrate such as an n-type single-crystal silicon substrate single crystal with pyramid-shaped irregularities P formed thereon, and an amorphous or microcrystal semiconductor layer formed on the single-crystal silicon substrate. A flat part F is formed in a valley portion of the pyramid-shaped irregularities P provided on a surface of the single-crystal silicon substrate. With this configuration, a steep angle of 70° to 85° of a concave portion formed by a substantially (111) surface can be widened to between 115° and 135°. Accordingly, a change of atomic step morphology attributable to a rounded shape can be eliminated, thereby enabling to reduce epitaxial growth and defects in the amorphous or microcrystal semiconductor layer.
    Type: Application
    Filed: October 15, 2012
    Publication date: March 12, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Aya Nishiyama, Hiroyuki Fuchigami, Hidetada Tokioka