Claims
- 1. A method of fabricating a non-volatile ferromagnetic random access memory element, comprising the steps of:
- depositing a multilayered structure including:
- a first ferromagnetic layer and a second ferromagnetic layer, said first ferromagnetic layer having a magnetic moment that is co-planar with said first ferromagnetic layer, said second ferromagnetic layer having a magnetic moment and two preferred axes of magnetic orientation for said magnetic moment of said second ferromagnetic layer, wherein one of said preferred axes of magnetic orientation is closer to a parallel alignment with said magnetic moment of said first ferromagnetic layer than is said other of said preferred axes of magnetic orientation;
- a non-magnetic metallic layer sandwiched between said first and second ferromagnetic layers;
- a first end conducting layer defining an upper end surface of said multilayered structure; and
- a second end conducting layer defining a lower end surface of said multilayered structure, onto an upper surface of an insulating substrate;
- depositing a first photoresist layer over an upper surface of said multilayered structure;
- photolithographically defining a first set of lines in said first photoresist layer;
- selectively removing portions of said first photoresist layer defined by said lines to expose corresponding portions of said upper surface of said insulating substrate;
- removing said first photoresist layer to provide an assembly having an upper surface of lines of said multilayered structure upon said upper surface of said insulating substrate;
- depositing an insulating layer to planarize said upper surface of said assembly;
- depositing a second photoresist layer upon said planarized surface;
- photolithographically defining lines in said second photoresist layer, said lines in said second photoresist layer traversing said lines of said multilayered structure;
- depositing a layer of conductive metal over said second photoresist layer to fill said lines in said second photoresist layer;
- removing said second photoresist layer.
- 2. The method of claim 1, wherein said portions of first photoresist layer are selectively removed by ion-milling.
- 3. The method of claim 1, wherein said first and second ferromagnetic layers comprise Fe, Co or Ni.
- 4. The method of claim 1, wherein one of said first and second ferromagnetic layers is a hard ferromagnetic metal and the other of said first and second ferromagnetic layers is a soft ferromagnetic metal.
- 5. The method of claim 4, wherein said hard magnetic metal has coercive field of at least 100 Oe and said soft magnetic metal has a coercive field of less than 100 Oe.
Parent Case Info
This is a division of copending application Ser. No. 08/130,479, filed Oct. 1, 1993, to Gary A. Prinz, titled ULTRA HIGH DENSITY, NON-VOLATILE FERROMAGNETIC RANDOM ACCESS MEMORY.
US Referenced Citations (3)
Non-Patent Literature Citations (3)
Entry |
H.J. Kump et al. "Coupled NDRO Magnetic Film Memory" IBM TDB vol.13, No. 7ec. 1970 pp.2110-2111. |
Thompson et al., "Thin Magnetoresistors in memory, shorage, and Related applications" IEEE Trans. On Magnetics IIC4, 1039-50 Jul. 1975. |
Binasch et al. "Enhanced Magnetoresistance In Layered Magnetic Structures With Antiferromagnetic Interlayer Exchange" Physical Rev. B. 39C7, 4828-30, Mar. 1, 1989. |
Divisions (1)
|
Number |
Date |
Country |
Parent |
130479 |
Oct 1993 |
|