2015/02/02 by Nihar Pradhan, N. R. Pradhan, D. Rhodes +21
Materials Science · Physics and Astronomy · #2D Materials and Applications #Condensed matter physics #Dangling bond #Dielectric #Electrical engineering #Electrical resistivity and conductivity #Electron mobility #Field effect #Field-effect transistor #Graphene research and applications #Hall effect #MXene and MAX Phase Materials #Materials science #Optoelectronics #Physics #Silicon #Substrate (aquarium) #Thermal conduction #Transistor #Variable-range hopping #Voltage #cond-mat.mes-hall
paper · pdf · doi:10.1038/srep08979
published as Sci. Rep. 5, 8979 (2015) · 35 pages including supplementary information. 7 figures in main text, 4 figures in supplementary file
arxiv created 2015/02/02 · openalex publication_date 2015/03/11 · arxiv updated 2015/03/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Here, we present a temperature (T) dependent comparison between field-effect and Hall mobilities in field-effect transistors based on few-layered WSe2 exfoliated onto SiO2. Without dielectric engineering and beyond a T-dependent threshold gate-voltage, we observe maximum hole mobilities approaching 350 cm(2)/Vs at T = 300 K. The hole Hall mobility reaches a maximum value of 650 cm(2)/Vs as T is lowered below ~150 K, indicating that insofar WSe2-based field-effect transistors (FETs) display the largest Hall mobilities among the transition metal dichalcogenides. The gate capacitance, as extracted from the Hall-effect, reveals the presence of spurious charges in the channel, while the two-terminal sheet resistivity displays two-dimensional variable-range hopping behavior, indicating carrier localization induced by disorder at the interface between WSe2 and SiO2. We argue that improvements in the fabrication protocols as, for example, the use of a substrate free of dangling bonds are likely to produce WSe2-based FETs displaying higher room temperature mobilities, i.e. approaching those of p-doped Si, which would make it a suitable candidate for high performance opto-electronics.