On January 30, a collaborative effort between the teams led by Prof. Jinlan Wang from the School of Physics, SEU and Prof. Xinran Wang from the Suzhou Laboratory/Nanjing University published their groundbreaking findings, entitled “Kinetic acceleration of MoS2 growth by oxy-metal-organic chemical vapor deposition,” online in the prestigious international academic journalScience (DOI: 10.1126/science.aec7259).
The team pioneered a growth strategy based on oxygen-assisted regulation of the reaction kinetics in oxy-metal-organic chemical vapor deposition (oxy-MOCVD). This successfully overcame the core technical challenges for mass-production of 6-inch (150 mm) transition metal sulfide (TMS) two-dimensional semiconductor singlecrystals. This breakthrough has fundamentally addressed critical issues such as carbon contamination, small crystalline domain size, and insufficient performance,aving the way for scaling up these novel materials from the lab to industrial applications,andmarking China’s entry into the international forefront in this field.
As a core candidate material for extending Moore’s Law, two-dimensional semiconductors like molybdenum disulfide (MoS?) and other transition metal sulfides offer unique advantages such as atomic-scale thickness, high carrier mobility, and low power consumption. They hold vast application potential in integrated circuits, flexible electronics, high-end sensors, and are considered a crucial direction for overcoming current bottlenecks in chip technology. However, their industrialization has long been hindered by a “mass production paradox”: commonly used lab techniques like chemical vapor deposition (CVD) can produce high-quality single crystals but are limited by small size, poor uniformity, and low reproducibility, failing to meet industrial demands. Conventional MOCVD, while promising for scale-up, is limited by reaction kinetics, often yielding polycrystalline materials with many defects and low electron mobility, unsuitable for high-performance electronic devices. Mass production technology for large-size and high-quality 2D semiconductor single crystals has thus been a core bottleneck restricting industry development.
Facing this “chokehold” challenge, Prof. Jinlan Wang’s teamfirst brokethe deadlock theoretically. Using first-principles calculations and simulations, the team discovered that in conventional MOCVD processes, the energy barrier for the sulfidation reaction of the precursor Mo(CO)? is as high as 2.02 eV. This severely limits the growth rate, restricting crystalline domain sizes to the nanometer scale, and makingthe process prone to carbon contamination. The key breakthrough came from the innovative idea of “introducing oxygen.” The team found that by introducing oxygen fundamentally reconstructs the reaction pathway: Mo(CO)? and CS? pre-react with oxygen to form molybdenum trioxide (MoO?) and active elemental sulfur intermediates. This not only lowers the reaction energy barrier from 2.02 eV to 1.15 eV, increasing the precursor reaction rate by approximately three orders of magnitude, but also suppresses the formation of carbon-containing intermediates at the source, completely solving the carbon contamination problem.
Guided by theory, the joint research team translated this core concept into an industrially viable technical solution. They designed a novel pre-reaction chamber structure to achieve precise mixing and pre-oxidation of oxygen with the precursors, thereby realizing a “carbon-free growth” mechanism. Experimental results demonstrate that this technique increases the MoS? crystalline domain size from the hundred-nanometer scale to several hundred micrometers (with a maximum of 260 μm) while achieving highly oriented alignment. Field-effect transistor arrays fabricated based on this material exhibit a maximum electron mobility of 123 cm2·V?1·s?1, a more than tenfold improvement over conventional methods, and an on/off ratio of 10?. These performance metrics fully meet the requirements for industrial applications. Crucially, the 6-inch fabrication scale precisely matches the current standards of semiconductor production lines, laying a solid foundation for subsequent technology transfer.
This achievement exemplifiesthesuccessful cross-institutional and interdisciplinary collaborative innovation at SEU. Ruikang Dong, a PhD graduate of SEU and now a postdoctoral researcher at the Suzhou Laboratory, is a co-first author of thispaper, and Prof. Jinlan Wang is a co-corresponding author. The researchwas funded by specialized programs such as the National Natural Science Foundation of China’s Innovative Research Group Project and Key Program. This technological breakthrough has not only validated the theoretical concept of “enhancing material quality through kinetic regulation” but also provides crucial support for China’s integrated circuit industry in overcoming technical bottlenecks and ensuring the security of industrial and supply chains.
Source: School of Physics, SEU
Translated by: Melody Zhang
Proofread by: Gao Min
Edited by: Leah Li
