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Possible Breakthrough of semiconductor manufacturing



As 3nm process manufacturing kicked-off, the development is not as smooth as expected. Associate Professor Lan Yann Wen and Postdoctoral researcher Chun I. Lu from the Department of Physics at National Taiwan Normal University participated in the Taiwan-German cross-border research team formed by the National Synchrotron Radiation Research Center (NSRRC). They have studied the "Cobalt/Molybdenum Disulfide Heterostructure" and found that through heterostructure "orbital hybridization", "spontaneous magnetic anisotropy" may be produced. If it is used in electronic components in the future, the development of semiconductor and optoelectronic industries may reach a breakthrough.

At present, the world is facing the physical limitations of traditional semiconductor materials, mainly in how to overcome the physical limit of shrinking in transistor and end Moore's Law, which indicates that the number of transistors in dense integrated circuits doubles roughly every two year. This has become the key to the urgent development of the semiconductor industry.

The international research team at NSRRC, led by Researcher Wei Der Hsin cooperates with Associate Professor Lan Yann Wen, Postdoctoral researcher Chun I. Lu from the Department of Physics and researcher Christian Tusche from Peter Grünberg Institute. They have spent more than 2 years to conduct the research of cobalt-molybdenum disulfide (Co/MoS2) heterojunction with Taiwan Light Source, TLS and Elettra.


The abstract of the paper is as follows:

Magnetic anisotropy (MA) is a material preference that involves magnetization aligned along a specific direction and provides a basis for spintronic devices. Here we report the first observation of strong MA in a cobalt-molybdenum disulfide (Co/MoS2) heterojunction. Element-specific magnetic images recorded with an X-ray photoemission electron microscope (PEEM) reveal that ultrathin Co films, of thickness 5 monolayers (ML) and above, form micrometer (μm)-sized domains on monolayer MoS2 flakes of size tens of μm. Image analysis shows that the magnetization of these Co domains is oriented not randomly but in directions apparently correlated with the crystal structure of the underlying MoS2. Evidence from micro-area X-ray photoelectron spectra (μ-XPS) further indicates that a small amount of charge is donated from cobalt to sulfur upon direct contact between Co and MoS2. As the ferromagnetic behavior found for Co/MoS2 is in sharp contrast with that reported earlier for non-reactive Fe/MoS2, we suggest that orbital hybridization at the interface is what makes Co/MoS2 different. Our report provides micro-magnetic and micro-spectral evidence that consolidates the knowledge required to build functional heterojunctions based on two-dimensional (2D) materials.