Molybdenum ditelluride (MoTe2) is a crystalline compound that if pure enough can be used as a transistor. Its molecular structure is an atomic sandwich made up of one molybdenum atom for every two tellurium atoms[HY1] . It was first made in the 1960's via several different fabrication methods, but until last year it had never been made in a pure enough form to be suitable for electronics.
Last year a multi-discipline research team led by South Korea's Institute for Basic Science (IBS) Center for Integrated Nanostructure Physics at Sungkyunkwan University (SKKU) director Young Hee Lee devised a fabrication method for the creation of pure MoTe2. Not only did they succeed in making MoTe2 in pure form, they were able to make two types of it -- a semiconducting variety called 2H-MoTe2 (2H because of its hexagonal shape) and a metallic variety called 1T'-MoTe2 (1T' because it has an octahedral shape) -- which are both stable at room temperature.
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