Reversible and Precisely Controllable p/n‐Type Doping of MoTe₂ Transistors through Electrothermal Doping

Abstract

Precisely controllable and reversible p/n-type electronic doping of molybdenum ditelluride (MoTe ) transistors is achieved by electrothermal doping (E-doping) processes. E-doping includes electrothermal annealing induced by an electric field in a vacuum chamber, which results in electron (n-type) doping and exposure to air, which induces hole (p-type) doping. The doping arises from the interaction between oxygen molecules or water vapor and defects of tellurium at the MoTe surface, and allows the accurate manipulation of p/n-type electrical doping of MoTe transistors. Because no dopant or special gas is used in the E-doping processes of MoTe , E-doping is a simple and efficient method. Moreover, through exact manipulation of p/n-type doping of MoTe transistors, quasi-complementary metal oxide semiconductor adaptive logic circuits, such as an inverter, not or gate, and not and gate, are successfully fabricated. The simple method, E-doping, adopted in obtaining p/n-type doping of MoTe transistors undoubtedly has provided an approach to create the electronic devices with desired performance.

Insulators for 2D nanoelectronics: the gap to bridge

“…As an attempt to address this limitation, 2D semiconductors, such as MoS 2 [10][11][12][13][14][15][16] , other transition metal dichalcogenides (TMDs, e.g. MoSe 2 17 , MoTe 2 18 , WS 2 19 , WSe 2 20 ) or black phosphorus (BP) [21][22][23] , have been recently demonstrated as channel materials in FETs.…”

High Mobilities in Layered InSe Transistors with Indium‐Encapsulation‐Induced Surface Charge Doping

“…Because of the down scaling limit of silicon‐based devices, 2D materials with prominent mechanical flexibility and carrier transport performance have provided significant potential for their use in the new generation atomic electronic devices . Following in the footsteps of the discovery of monolayer graphene in 2004, diverse layered transition metal dichalcogenides with tunable band gaps have been shown to exhibit extraordinary electrical and optical properties in logic circuits, photodetectors, light‐emitting diodes, gas sensors, and energy storage devices . However, owing to their low mobility ceiling of a few hundred cm 2 V −1 s −1 , 2D‐based field‐effect transistors (FETs) still encounter a bottleneck for their application in high‐frequency electronic devices.…”

“…With an increase of the In thickness, a larger band bending occurs, and, subsequently, a stronger surface charge transfer can be expected. Taking the equation of n ∝ exp (−Δ E / k B T ) into consideration, where Δ E = E C − E F , k B , and T are the energy difference between the E C and the E F , the Boltzmann constant, and the absolute temperature in Kelvin, respectively, the Δ E for both the w/o In and w/In 32 nm thick cases could be roughly quantified . Compared with the w/o In FETs, the E F position occurs an upward shift close to E C in the w/In 32 nm thick FETs through the SCTD procedure; this difference between Δ E (for w/o) and Δ E (for w/In) could be further quantified to be 50 meV.…”

p-/n-Type modulation of 2D transition metal dichalcogenides for electronic and optoelectronic devices

“…Therefore, the main PL peak of MoS2 and WSe2 shifted along with the change of doping levels. Utilizing the p-type doping effect of H2O and O2 adsorption, a reversible doping of MoTe2 could be realized by electrothermal annealing, that modulate the adsorption and desorption processes of H2O and O2 [117]. When MoTe2 was annealed in vacuum, H2O and O2 were desorbed and refreshed the original conduction type of MoTe2 (n-type) (procedure 1 to 2 in Fig.…”