Patent · US Expired

Magnetic semiconductor memory apparatus and method of manufacturing the same

US6560135B2 · kind B2 · utility

66Cited by
3References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 23, 2001
Grant dateMay 6, 2003
Priority date
Expiry dateAug 23, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B61/10

Abstract

Since a memory cell of a so-called MRAM utilizing a conventional tunnel magnetic resistance forms writing word lines below data lines, there are the following problems. A process becomes hard because it is necessary to execute a self-aligned contact opening process with passing through portions between the writing word lines, or since it is hard that the writing word lines sufficiently overlap with a magnetic resistance device in a planner manner due to a restriction of layout, the data writing becomes unstable. In order to solve the problems mentioned above, the present invention provides a structure of MRAM memory cell in which the writing word lines are formed above the bit lines, and a method of manufacturing the same. In accordance with the present invention, a process at a time of forming a memory cell plug becomes easy in comparison with a conventional one, there can be obtained a layout so that a magnetic field from the writing word line effectively acts on a magnetic resistance device due to the writing word line formed in an upper portion, and a stable writing can be executed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.