Improved Electrical Performance Thanks to Sb and N Doping in Se-Rich GeSe-Based OTS Selector Devices

Abstract

In this paper, we investigate the impact of Sb and N doping in Se-rich GeSe based Ovonic Threshold Switching (OTS) selector devices, targeting crossbar memory applications. Through physico-chemical analysis and electrical characterization we demonstrate that Sb doping allows low threshold voltage switching operations, while N doping improves the OFF state resistance stability of Se-rich GeSe based selector devices. Thus, we are able to demonstrate an endurance up to 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> cycles, an ON/OFF current ratio of ~ 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> and reading selectivity of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> . These values are among the best reported in the literature for an OTS selector. The described material engineering makes Se-rich GeSe based materials suitable for Back-End of Line (BEOL) selector integrations, such as resistive memory crossbar arrays up to 1Mb.