List of Thin Film Samples Available

WS2 on (0001) sapphire

2H-WS2 in monolayer form is a semiconductor with a room temperature optical gap of ~2 eV. This sample is a continuous epitaxial film of WS2 grown by MOCVD on a 2” diameter (0001) sapphire that is monolayer with 5-15% bilayer domain coverage and inversion domain fraction ranging from 5-35% within the monolayer.  See example certification sheet for more information.

MoS2 on (0001) sapphire

2H-MoS2 in monlayer form is a semiconductor with a room temperature optical gap of ~1.85 eV. This sample is a continuous epitaxial film of MoS2 grown by MOCVD on 2” diameter (0001) sapphire that is monolayer with 5-15% bilayer domain coverage. Inversion domain fraction has not yet been determined.  See example certification sheet for more information.

WSe2 on (0001) sapphire 

2H-WSe2 in monolayer form is a semiconductor with a room temperature optical gap of ~1.65 eV. This sample is a continuous epitaxial film of WSe2 grown by MOCVD on 2” diameter (0001) sapphire that is monolayer with 20% bilayer domain coverage. Inversion domain fraction has not yet been determined.

WSe2 on (0001) sapphire - Monolayer

2H-WSe2 in monolayer form is a semiconductor with a room temperature optical gap of ~1.64 eV. This sample is a continuous epitaxial film of WSe2 grown by MOCVD on 1 cm × 1 cm (0001) sapphire that is monolayer with 30-40% bilayer domain coverage. Inversion domain fraction has not yet been determined.  See example certification sheet for more information.

 

Photo coming

soon!

WSe2 on (0001) sapphire – Multi-layer

Our 2H-WSe2 multi-layer films are a semiconductor with a uniform distribution of Raman spectra breathing mode at 310 cm-1 at room temperature. This sample is a continuous epitaxial film of WSe2 grown by MOCVD on 1 cm × 1 cm (0001) sapphire that is >95% bilayer with 30-40% trilayer domain coverage. Inversion domain fraction has not yet been determined.  See example certification sheet for more information.

MoSe2 on (0001) sapphire

2H-MoSe2 in monolayer form is a semiconductor with a room temperature optical gap of ~1.58 eV. This sample is a continuous epitaxial film of MoSe2 grown by MOCVD on 2” diameter (0001) sapphire that is monolayer with 50-75% bilayer domain coverage. Inversion domain fraction has not yet been determined.

PtSe2 on (0001) sapphire

Bulk PtSe2 is a layered semimetal but in the monolayer form it is semiconducting with a room temperature optical gap of ~1.2 eV. PtSe2 ranges among the highest room-temperature electron mobility two-dimensional materials and is air-stable. This sample is a continuous epitaxial film of PtSe2 grown by MBE on (10x10) mm square (0001) sapphire. The PtSe2 layer is about 4 nm thick and single crystal. The rms surface roughness measured by AFM is about 0.4 nm.

Graphene on Cu Foils

Our CVD-grown graphene thin films on Cu foils are polycrystalline with >99.99% single-layer coverage with a maximum lateral size of ~30 x 50 mm2. Upon request, additional graphene layers can be grown under the first layer (max lateral size ~100 microns, up to 3 layers). See example certification sheet (part 1, part 2) for more information.

Epitaxial Graphene

Epitaxial graphene was formed on 6H-SiC (0001) in a graphite crucible via Si sublimation from the Si side of the substrate. By tuning the experimental conditions, EG samples with different thicknesses ranging from a buffer layer to 2-3 layers can be synthesized in a highly controlled fashion. See example certification sheet for more information.

Bi2Se3 on sapphire (0001), InP (111)A or GaAs (111)B

Bi2Se3 is a topological insulator with a band gap of ~0.3 eV. Due to intrinsic defects our MBE grown films are n-type with carrier densities around 1019 cm-3. Twinned inversion domain fractions range from 10-40% on sapphire and InP substrates, while GaAs has roughly equal orientations. Se capping is available.

 

Photo coming

soon!

(BixSb1-x)2Te3 on sapphire (0001), InP (111)A, GaAs (111)B or SrTiO3 (111)

(Cr and V doping available)

(BixSb1-x)2Te3 is topological insulator with a band gap of ~0.15 eV, depending on composition. The carrier density of our MBE grown thin films can be tuned with the Bi to Sb ratio so that the chemical potential can be placed very near the Dirac point. With Cr or V doping this allows samples that exhibit the quantum anomalous Hall effect (QAHE). SrTiO3 substrates can be used to back gate the samples. Se or Te capping is also available.

 

Share