Tunable Schottky barrier width and enormously enhanced photoresponsivity in Sb doped SnS2 monolayer

Abstract

Doping, which is the intentional introduction of impurities into a material, can improve the metal-semiconductor interface by reducing Schottky barrier width. Here, we present high-quality two-dimensional SnS 2 nanosheets with well-controlled Sb doping concentration via direct vapor growth approach and following micromechanical cleavage process. X-ray photoelectron spectroscopy (XPS) measurement demonstrates that Sb contents of the doped samples are approximately 0.22%, 0.34% and 1.21%, respectively, and doping induces the upward shift of the Fermi level with respect to the pristine SnS 2. Transmission electron microscopy (TEM) characterization exhibits that Sb-doped SnS 2 nanosheets have a high-quality hexagonal symmetry structure and Sb element is uniformly distributed in the nanosheets. The phototransistors based on the Sb-doped SnS 2 monolayers show n-type behavior with high mobility which is one order of magnitude higher than that of pristine SnS 2 phototransistors. The photoresponsivity and external quantum efficiency (EQE) of Sb-SnS 2 monolayers phototransistors are approximately three orders of magnitude higher than that of pristine SnS 2 phototransistor. The results suggest that the method of reducing Shottky barrier width to achieve high mobility and photoresponsivity is effective, and Sb-doped SnS 2 monolayer has significant potential in future nanoelectronic and optoelectronic applications.

On the Role of Contact Resistance and Electrode Modification in Organic Electrochemical Transistors

“…In brief, as V G is applied and electrons are injected from the Au S/D electrodes, cations are drawn from the electrolyte into the n‐type OSC . Electrons are subsequently transferred/donated from the ions to dope the OSC, shifting the Fermi level and reducing the height/width of the Schottky barrier, hence reducing R C . This results in similar R C at high V G , regardless of the initial R C magnitude.…”

Effective Modulation of Optical and Photoelectrical Properties of SnS2 Hexagonal Nanoflakes via Zn Incorporation

“…Similarly, in our previous work, we reported enhanced optical and electrical properties of SnS 2 nanoflakes via Cu doping [35]. More recently, Liu et al reported enhanced photoresponsivity in Sb doped SnS 2 monolayer [36]. Based on the above literatures we test the ability of doping Zn ions in SnS 2 to significantly enhance conductivity and sensitivity favorable for its performance in photoelectronics.…”

Novel two-dimensional monoelemental and ternary materials: growth, physics and application

“…Last but not the least, Duan et al used their famous two-step CVD method to fabricate a Sb/WSe 2 heterostructure. The thickness of Sb nanosheet on WSe 2 can be effectively reduced to monolayer [45].…”

“…Nevertheless, because of the covalent bonding between the anion/ion atoms and the general weak interlayer coupling effect, TMCs and their heterostructures have suffered from intrinsic/extrinsic disorder (vacancies, anti-site, substitution) and interface impurity (small molecules), leading to the downtrend or strange phenomenon in electronic and optoelectronic properties [38,39]. Fortunately, the charge transport [40], photoluminescence [41], layer-dependent magnetism [42] and electrical properties [43][44][45][46] of TMCs can be enhanced via some specific kinds of defects (point substitution or deep levels). Among them, monoelement doping in 2DLMs has attracted researchers because of the unique properties of monoelements.…”