p-type doping of MoS₂ thin films using Nb

Abstract

We report on the first demonstration of p-type doping in large area few-layer films of (0001)-oriented chemical vapor deposited (CVD) MoS 2 . Niobium was found to act as an efficient acceptor up to relatively high density in MoS 2 films. For a hole density of 4 x 10 20 cm -3Hall mobility of 8.5 cm 2 V -1 s -1 was determined, which matches well with the theoretically expected values. XRD and Raman characterization indicate that the film had good out-of-plane crystalline quality. Absorption measurements showed that the doped sample had similar characteristics to high-quality undoped samples, with a clear absorption edge at 1.8 eV. This demonstration of p-doping in large area epitaxial MoS 2 could help in realizing a wide variety of electrical and opto-electronic devices based on layered metal dichalcogenides.

Noncollinear exchange interaction in transition metal dichalcogenide edges

“…We consider p-doped triangular flakes with 50 rows of metal atoms, corresponding to 1275 sites ( 160Å on edge). We note that p doping has been achieved experimentally by substituting Mo by Nb in CVD-grown MoS 2 films [38], consistent with first principles studies [39]. Other suggestions include replacing Mo with Mn [40], and doping with a wide class of transition metal atoms [41].…”

“…In this Rapid Communication we use a three-orbital tightbinding model [37] to study the interaction between two magnetic impurities in zigzag-terminated MoS 2 nanoflakes with different Fermi levels, as provided by doping or gating of the sample [38][39][40][41]. For Fermi levels at midgap energies, associated with states located at the flake edges, we explore the role of 1D and strong SOC on the effective exchange interaction between impurities.…”

<inline-formula> <tex-math notation="TeX">${\rm MoS}_{2}$ </tex-math></inline-formula> Field-Effect Transistors With Graphene/Metal Heterocontacts

“…The on-state performance of the MoS 2 FETs is mainly limited by the large contact resistance at MoS 2 /metal interfaces [4][5][6][7][8][9]. Recent attempts to improve MoS 2 contacts had been concentrated on the following areas using:(1) low work function contact metal [10], (2) gas doping of MoS 2 flakes [11], and (3) molecular or solid doping on MoS 2 films [12,13]. However, the fundamental reason for the large contact resistance is the result of Fermi level pinning on MoS 2 near conduction band edge due to S-vacancy defect level and charge neutral level location [14,15].…”

Phosphorous doped p-type MoS2 polycrystalline thin films via direct sulfurization of Mo film

“…Therefore considerable efforts are required for scalable synthesis of p-type MoS 2 film to realize practical applications. To date, a direct growth method of MoS 2 thin films by chemical vapor deposition (CVD) via vapor-phase reaction of MoO 3 and sulfur (S) powders, [18][19][20][21] MoCl 5 and S powders, 22,23 and metal Mo films [24][25][26][27][28] in a CVD furnace have been demonstrated to overcome a large area film synthesis. Among them, the direct grown method of TMDs (e.g.…”