Two mask MTJ integration for STT MRAM
A method for forming a magnetic tunnel junction (MTJ) for magnetic random access memory (MRAM) using two masks includes depositing over an interlevel dielectric layer containing an exposed first interconnect metallization, a first electrode, a fixed magnetization layer, a tunneling barrier layer, a free magnetization layer and a second electrode. An MTJ structure including the tunnel barrier layer, free layer and second electrode is defined above the first interconnect metallization by a first mask. A first passivation layer encapsulates the MTJ structure, leaving the second electrode exposed. A third electrode is deposited in contact with the second electrode. A second mask is used to pattern a larger structure including the third electrode, the first passivation layer, the fixed magnetization layer and the first electrode. A second dielectric passivation layer covers the etched plurality of layers, the first interlevel dielectric layer and the first interconnect metallization.
QUALCOMM Incorporated
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H01L G11C H01L
inventional inventional inventional
Seung H. Shiqun Xia Matthew
Kang Gu Li Nowak