Fabrication of NbO₂ based IMT Selector Devices via a 300mm Based Memory Test Vehicle

The demand for differentiated devices in the backend-of-line increases necessitates the need for a test vehicle that enables the integration and electrical characterization of such devices. An Insulator-Metal Transition based NbO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> device was integrated onto the NY CREATES/UAlbany memory test vehicle (MTV) utilizing a 65nm process technology to fabricate nanoscale devices with a footprint down to 120x120 nm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>. NbO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>, the metastable allotrope of niobium oxide, was deposited onto coupons diced out of the 300mm MTV. This occurred in an oxygen-controlled environment yielding phase-pure NbO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> after a 750 °C crystallization anneal. An endurance of at least 25x10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> cycles was demonstrated with an R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</inf>/R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</inf> ratio above 100 and an extrapolation towards >2000 with further device scaling.