Inventors:
JiJun Sun - Chandler AZ, US
John T. Martin - Chandler AZ, US
Jon M. Slaughter - Tempe AZ, US
Assignee:
Everspin Technologies, Inc. - Chandler AZ
International Classification:
H01L 21/316, H01L 27/115
US Classification:
438768, 438765, 257E2128, 3603242, 365158
Abstract:
Methods and apparatus are provided for magnetic tunnel junction (MTJ) devices and arrays, comprising metal-insulator-metal (M-I-M) structures with opposed first and second ferro-magnetic electrodes with alterable relative magnetization direction. The insulator is formed by depositing an oxidizable material (e. g. , Al) on the first electrode, naturally oxidizing it, e. g. , at about 0. 03 to 10 milli-Torr for up to a few thousand seconds at temperatures below about 35° C. , then further rapidly (e. g. , plasma) oxidizing at a rate much larger than that of the initial natural oxidation. The second electrode of the M-I-M structure is formed on this oxide. More uniform tunneling properties result. A second oxidizable material layer is optionally provided after the initial natural oxidation and before the rapid oxidation step during which it is substantially entirely converted to insulating oxide. A second natural oxidation cycle may be optionally provided before the second layer is rapidly oxidized.