p-type MoSe2 crystals

More than a decade of growth optimization in chemical vapor transport (CVT) as well as flux growth lead to our flawless MoSe2 crystals. Our p-type MoSe2 crystals are doped with Nb atoms at 1E17-5E18cm-3 range. These electronically doped vdW MoSe2 crystals are treated as gold standards in 2D materials field. MoSe2 crystals from 2Dsemiconductors are known for its superior valleytronic performance, perfect crystallization, defect free structure, extremely narrow PL bandwidths, clean PL spectra (free of bound exciton shoulders), and high carrier mobility. Thousands of scientific articles have cited us and used these crystals for scientific accuracy and clean signals. Please also see our n- and p-type MoSe2 crystals doped with Au, Re, Nb, or other transition metal atoms.

Please note that doping into TMDCs greatly reduce the crystallization time (growth speeds), thus electronically doped TMDCs measure smaller than undoped (intrinsic) TMDCs.

Single crystal p-doped MoSe2 characteristics

Growth method matters> Flux zone or CVT growth method? Contamination of halides and point defects in layered crystals are well known cause for their reduced electronic mobility, reduced anisotropic response, poor e-h recombination, low-PL emission, and lower optical absorption. Flux zone technique is a halide free technique used for synthesizing truly semiconductor grade vdW crystals. This method distinguishes itself from chemical vapor transport (CVT) technique in the following regard: CVT is a quick (~2 weeks) growth method but exhibits poor crystalline quality and the defect concentration reaches to 1E11 to 1E12 cm-2 range. In contrast, flux method takes long (~3 months) growth time, but ensures slow crystallization for perfect atomic structuring, and impurity free crystal growth with defect concentration as low as 1E9 - 1E10 cm-2. During check out just state which type of growth process is preferred. Unless otherwise stated, 2Dsemiconductors ships Flux zone crystals as a default choice. 

http://meetings.aps.org/Meeting/MAR18/Session/K36.3

Summary of available doped layered materials

MoS2; n-type and p-type available (via Nb, Co, Ni, Au, or Re dopants)

WS2; n-type and p-type available (via Au or Nb doping; 

WSe2; n-type and p-type available (via Re or Nb doping)

MoSe2 ; n-type and p-type available (via Re or Nb doping)

Black phosphorus; n-type or p-type doping available (via Br or As doping)

ReX2 (X=S, Se); n-type or p-type doping available (via Mo or Nb doping)

Bi2X3 (X=S,Se, and Te); n-type or p-type doping available (via Ca doping)

XRD datasets collected from MoSe2

HRTEM image collected from MoSe2 crystals

Photoluminescence specturm collected from MoSe2 at 300K

Raman spectrum collected from MoSe2 sheets

Publications from this product 

Summary: Publications from MIT, Berkeley, Stanford, Rice, and Harvard teams at top journals like Nature, Nature Communications, Nano Letters, and Advanced Materials

Control of Exciton Valley Coherence in Transition Metal Dichalcogenide Monolayers, Phys. Rev. Lett. 117, 187401 (2016)

Measurement of the optical dielectric function of monolayer transition-metal dichalcogenides: MoS2, MoSe2, WS2, and WSe2, Yilei Li, Alexey Chernikov, Xian Zhang, Albert Rigosi, Heather M. Hill, Arend M. van der Zande, Daniel A. Chenet, En-Min Shih, James Hone, and Tony F. Heinz; Phys. Rev. B 90, 205422 (2014)

Y. Jin "A Van Der Waals Homojunction: Ideal p–n Diode Behavior in MoSe2" Advanced Materials 27, 5534–5540 (2015)

Tongay et. al. "Defects activated photoluminescence in two-dimensional semiconductors: interplay between bound, charged, and free excitons" Scientific Reports 3, Article number: 2657 (2013)

M. Yankowitz et. al. "Intrinsic Disorder in Graphene on Transition Metal Dichalcogenide Heterostructures" Nano Letters, 2015, 15 (3), pp 1925–1929

Tongay et.al. Thermally Driven Crossover from Indirect toward Direct Bandgap in 2D Semiconductors: MoSe2 versus MoS2; Nano Letters, 2012, 12 (11), pp 5576–5580

Manish Chhowalla, "Two-dimensional semiconductors for transistors" Nature Reviews Materials 1, Article number: 16052 (2016) doi:10.1038/natrevmats.2016.52

X Li et al. "Determining layer number of twodimensional flakes of transition-metal dichalcogenides by the Raman intensity from substrates" Nanotechnology 27 (2016) 145704