Ballistic electron microscopy study of ultrathin oxidized aluminum barriers for magnetic tunnel junctions
نویسندگان
چکیده
Ballistic electron emission microscopy has been used to study thin aluminum oxide tunnel junction barriers formed both by magnetron sputter deposition and thermal evaporation. We have found that the barriers made by oxidation of evaporated Al become fully formed at a significantly thinner mean deposited thickness ~;6 Å! than junctions made by sputter deposition. The effective barrier height of the aluminum oxide has been determined to be 1.2260.05 eV and is independent of the method of deposition, thickness, and oxidation conditions. © 2001 American Institute of Physics. @DOI: 10.1063/1.1352045#
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