Active solid-state devices (e.g. – transistors – solid-state diode – Field effect device – Having insulated electrode
Reexamination Certificate
2005-03-10
2010-12-07
Chambliss, Alonzo (Department: 2892)
Active solid-state devices (e.g., transistors, solid-state diode
Field effect device
Having insulated electrode
C257S427000, C257SE29323, C257SE27104, C257SE29164, C257SE21208, C365S171000
Reexamination Certificate
active
07847327
ABSTRACT:
The output voltage of an MRAM is increased by means of an Fe(001)/MgO(001)/Fe(001) MTJ device, which is formed by microfabrication of a sample prepared by the following steps. A single-crystalline MgO (001) substrate11is prepared. An epitaxial Fe(001) lower electrode (a first electrode)17with the thickness of 50 nm is grown on a MgO(001) seed layer15at room temperature, followed by annealing under ultrahigh vacuum (2×10−8Pa) and at 350° C. A MgO(001) barrier layer21with the thickness of 2 nm is epitaxially formed on the Fe(001) lower electrode (the first electrode) at room temperature, using a MgO electron-beam evaporation. A Fe(001) upper electrode (a second electrode) with the thickness of 10 nm is then formed on the MgO(001) barrier layer21at room temperature. This is successively followed by the deposition of a Co layer21with the thickness of 10 nm on the Fe(001) upper electrode (the second electrode)23. The Co layer21is provided so as to increase the coercive force of the upper electrode23in order to realize an antiparallel magnetization alignment.
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A. Marquez, Esq. Juan Carlos
Chambliss Alonzo
Japan Science and Technology Agency
National Institute of Advanced Industrial Science and Technology
Stites & Harbison PLLC
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