Repairing atomic vacancies in single-layer MoSe2 field-effect transistor and its defect dynamics

Abstract

Atomic defects are easily created in the single-layer electronic devices of current interest and cause even more severe influence than in the bulk devices since the electronic quantum paths are obviously suppressed in the two-dimensional transport. Here we find a drop of chemical solution can repair the defects in the single-layer MoSe 2 field-effect transistors. The devices' roomtemperature electronic mobility increases from 0.1 cm 2 /Vs to around 30 cm 2 /Vs and hole mobility over 10 cm 2 /Vs after the solution processing. The defect dynamics is interpreted by the combined study of the first-principles calculations, aberration-corrected transmission electron microscopy, and Raman spectroscopy. Rich single/double Selenium vacancies are identified by the highresolution microscopy, which cause some mid-gap impurity states and localize the device carriers. They are found to be repaired by the processing with the result of extended electronic states. Such a picture is confirmed by a 1.5 cm −1 red shift in the Raman spectra.

Improved Current Density and Contact Resistance in Bilayer MoSe2 Field Effect Transistors by AlOx Capping

“…Our AlO x -capped 2L devices achieve a record-high current density for atomically thin MoSe 2 of ∼65 μA/μm, with an I on / I off > 10 6 and R C of ∼60 kΩ·μm. 30 , 34 , 38 − 40 These results represent ∼20× improvement in R C and ∼30× enhanced current density compared to our (AlO x -capped) 1L devices. The AlO x doping effect aligns well with previously reported data for 1L and FL MoS 2 and ReS 2 encapsulation.…”

Flexible, Semitransparent, and Inorganic Resistive Memory based on BaTi0.95Co0.05O3 Film

“…Although all the conductive filaments already broke during the postannealing, its resistive‐switching parameters and flexible performance could recover to those of the original memory after the postannealed memory underwent electric forming at room temperature (Figure S8, Supporting Information). In a word, this temperature stability is better than those of the widely used flash memory and most organic memories under study …”

Chlorine doping of MoSe2 flakes by ion implantation

“…As an example, Se vacancies at the MoSe2 surface can be treated with Ethylenediaminetetraacetic acid (EDTA) disodium salt solution. 28 The EDTA molecules interact with the MoSe2 surface and they are bonded at the place of Se vacancies, significantly improving the carrier mobility. The efficient doping of MoS2 was realized also by the intercalation of Li, Na, or K ions.…”