Physical And Electrical Characterization of MoS₂ Layers Deposited by RF Magnetron Sputtering for 2D FETs

The electrical characterization by capacitance-voltage (CV) and by current-voltage (IV) measurements of Metal-Insulator-Semiconductor structures (MIS) using HfO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> as dielectric and MoS <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> as semiconductor layer, respectively, is presented, where both layers are deposited at room temperature by RF magnetron sputtering, from HfO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> and MoS <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> targets, respectively. Samples with and without temperature annealing are analyzed. The resistivity of the deposited layers as function of annealing temperature decreased in more than two orders after the annealing at 300 °C. The deposited MoS <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> layer presented P-type conductivity as revealed by CV measurements in MIS capacitors (Mo/HfO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> /MoS <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> /Mo), which seems to be related to plasma processes used during the fabrication of the devices. The calculated charge concentration of the MoS <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> layer was in the order of 3.9x10 16 cm -3 . The CV characteristics revealed bias stability, as well as repeatability of the fabrication processes. The presence and thickness of the MoS <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> layer was confirmed by Secondary Ion Mass Spectroscopy (SIMS) and Raman Spectroscopy.