- Frequently Asked Questions
Frequently Asked Questions
Find quick answers to your questions below...
What is a good email address to reach 2Dsemiconductors?
support _at_ 2dsemiconductors.com
Placing an order is as easy adding the item to the basket and proceeding to checkout. You can make the payment securely using Visa and Mastercard. For purchase orders (PO) please contact us.
What about Shipping&Handling?
Domestic (U.S states and territories): Our preferred courier service is FedEx. However, we can make arrangement if you prefer different service. We provide FedEx tracking number so that you can track your package.
International: We ship using FedEx services. It usually takes one (1) week to be delivered. FedEx delivers faster and does not experience long wait at the border. However, we can make arrangement if you prefer different service. We provide FedEx tracking number so that you can track your package.
How good are your synthetic materials?
At 2Dsemiconductors, we deliver World’s most pure and highest quality layered materials. Most of our materials are defect free, high quality, and 99.99% pure. Flakes from each growth batch are tested using advanced techniques as such XPS, AES, Raman, PL, XRD, SEM, STM, ARPES, and LEED. After all these tests, materials are tested using electrical conductivity, dielectric property, optical property tests. You can be 100% sure that the material is high quality and reliable.
How good are the naturally occurring bulk MoS2 samples?
All the natural MoS2 pieces are recovered from mines that have the least amount of defect and impurities. We currently disregard more than 95% of the mined MoS2 samples to provide you the top 5% the most pure flakes. MoS2 flakes are shiny, and layered. Samples are easy to cleave. Our materials show good physical properties such as high PL intensity at 670nm (when exfoliated to monolayers) and broad PL at 950nm in bulk. FWHM of Raman peaks are much lower than 5cm-1 indicating high crystallization. Further tests such as LEEDs, XRD, XPS, AES, SIMS, PL, Raman, AFM, and STM measurements are done routinely to test to quality of our materials.
How are the transitional metal dichalcogenides (MoS2, MoSe2, WS2, WSe2, ReSe2, SnSe2) grown?
Our synthetic layered materials - flakes are grown at our facilities in three (3) to six (6) full weeks. Our final product is pristine and very high quality. Please see each product description for detailed information or contact us via email.
How are the transitional metal chalcogenides (GaS, GaSe, GaTe) and other materials grown?
Transitional metal chalcogenides are grown at our facilities in 3 months using state-of-art techniques developed at our facilities. Our final product is pristine and very high quality. Please see each product description for detailed information or contact us via email.
How can I locate monolayer semiconductor?
We provide you the x and y coordinates of the monolayer semiconductor from the labelled part of the corner and are visible under the conventional 50-100x microscope.
Are monolayers visible?
Yes. The thickness of the thermal oxide has been optimized in a way that the contrast is at maximum and the monolayer semiconductors are visible under conventional optical microscope.
How many monolayer semiconductors does each sample contain?
At least one. However, we only provide (x,y) coordinates for one monolayer flake.
What are the typical sizes for monolayers?
The order of magnitude size of the monolayer is specified in the sample specifications and on the sample box. If you have any specification, please let us know or contact via email.
What is the origin of the bulk MoS2 (2H-MoS2)?
Naturally occurring MoS2 crystals were recovered by our miners all around the world; Russia, Australia, and Peru. In our experience, the most crystalline samples originate from Peru. If you have any specific request about the origin of the piece you like to receive, please contact us.
What to pick? Synthetic MoS2 or Naturally occurring MoS2?
Our synthetic MoS2 flakes are grown in our laboratories in three (3) full weeks, 21 days. Our final product is superior to natural MoS2 as it has least amount of impurities and defects. Typically, the crystal size is larger and exfoliation process yields large monolayer flakes.
What does sample with data mean?
We are glad to provide you the Raman spectroscopy, photoluminescence data, and optical images on the bulk pieces for extra charge. Such data is taken on various spots providing the digital data for your own records and use. However, monolayer MoS2 product already includes these measurements along with the (x,y) coordinates of the monolayer MoS2 making easier for you to spot the piece.