Discipline: Technology and Engineering
Subcategory: Materials Science
Patrick Rondomanski - Pennsylvania State University
Co-Author(s): Xiaotian Zhang, Joan M. Redwing, Pennsylvania State University, University Park, PA
Silicon integrated circuits have advanced quickly and reached their limits. The overall goal of this research project is to develop a synthesis process for SnS2 and SnSe2 thin films and investigate WSe2/SnS2/graphene and WSe2/SnSe2/graphene heterostructures to create tunneling transistors as replacements for conventional silicon complementary metal oxide semiconductors (CMOS) in low power integrated circuits. In this study, tin disulfide films were grown at atmospheric pressure using a horizontal hot-walled reactor. Precursors of sulfur and tin powders were placed at different locations inside of a liner tube that runs through the reactor with nitrogen gas flowing through it. The sulfur was placed near the inlet of the reactor with a temperature of ~400°C, and the tin was placed at the center of the reactor with a temperature of ~700°C. This allows both powders to supply sufficient vapor pressure to promote the reaction above and transfer to the substrate. In addition to the precursor vapor pressure, the total flow rate has a significant impact on the film deposition. The results show that the amount of tin disulfide deposited decreases with decreasing total flow rate. The total flow rate also affects the location of the film deposition. Higher flow rates require the substrate to be located further downstream from the tin precursor. By tuning the location of the substrate, we are able to achieve a uniform SnS2 thin film on c-plane sapphire substrate. Further investigation will focus on the growth of WSe2/SnS2/graphene and WSe2/SnSe2/graphene heterostructures and characterization of their properties.
Funder Acknowledgement(s): Financial support for this work was provided by the National Science Foundation through the EFRI REM program (Grant No. EFMA-1433378).
Faculty Advisor: Joan M. Redwing, firstname.lastname@example.org
Role: The synthesis and characterization of the thin films.