Active solid-state devices (e.g. – transistors – solid-state diode – Responsive to non-electrical signal – Magnetic field
Reexamination Certificate
2007-01-30
2009-10-06
Phung, Anh (Department: 2824)
Active solid-state devices (e.g., transistors, solid-state diode
Responsive to non-electrical signal
Magnetic field
C257S427000, C257SE21665, C365S158000, C365S171000
Reexamination Certificate
active
07598579
ABSTRACT:
A MTJ that minimizes spin-transfer magnetization switching current (Jc) in a Spin-RAM to <1×106A/cm2is disclosed. The MTJ has a Co60Fe20B20/MgO/Co60Fe20B20configuration where the CoFeB AP1 pinned and free layers are amorphous and the crystalline MgO tunnel barrier is formed by a ROX or NOX process. The capping layer preferably is a Hf/Ru composite where the lower Hf layer serves as an excellent oxygen getter material to reduce the magnetic “dead layer” at the free layer/capping layer interface and thereby increase dR/R, and lower He and Jc. The annealing temperature is lowered to about 280° C. to give a smoother CoFeB/MgO interface and a smaller offset field than with a 350° C. annealing. In a second embodiment, the AP1 layer has a CoFeB/CoFe configuration wherein the lower CoFeB layer is amorphous and the upper CoFe layer is crystalline to further improve dR/R and lower RA to ≦10 ohm/μm2.
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Horng Cheng T.
Tong Ru-Ying
Ackerman Stephen B.
Bernstein Allison P
MagIC Technologies, Inc.
Phung Anh
Saile Ackerman LLC
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