Michigan State University Physicists Develop New Method for Atomic-Scale Semiconductor Analysis

TapTechNews July 7th news, physicists at Michigan State University (MSU) have developed a new way to analyze semiconductors at the atomic scale. This method combines high-resolution microscopy with ultrafast lasers to detect the defects of semiconductors in an unprecedented way.

This research, led by Tyler Cocker, the Jerry Cowen Endowed Chair in Experimental Physics at Michigan State University, aims to overcome long-standing challenges. As devices become smaller and more powerful, tools to examine the constituent materials of devices become crucial.

This is especially important for components with nanoscale structures, Cocker explained. The application scope of this technology can be extended to the cutting-edge development of semiconductor technologies, including computer chips with nanoscale features and engineered materials just one atomic thick.

This new method can detect silicon atoms added to gallium arsenide, which is crucial in radar systems, high-efficiency solar cells, and modern telecommunication devices. These silicon atoms play a crucial role in regulating the movement of electrons through the semiconductor.

Although theoretical physicists have studied this type of defect for decades, the experimental detection of individual atoms has been difficult to achieve so far. For electrons, silicon atoms basically look like a deep pit, Cocker explained.

The research team at Michigan State University combined a scanning tunneling microscope (STM) with laser pulses at terahertz frequencies. These pulses flutter up and down a trillion times per second, and this combination creates a defect-sensitive probe.

When the STM probe encounters a silicon defect on the surface of gallium sulfide, a significant strong signal is generated in the measurement data. If the probe is moved by one atomic, the signal disappears.

As semiconductor devices continue to shrink, understanding and controlling atomic-scale defects becomes important for the performance and stability of devices.

TapTechNews noted that Cocker's team has already applied their method to examining atomically ultrathin materials such as graphene nanowires. We are conducting many open-ended projects, using this technology to study more materials and more exotic materials, he said. We basically incorporate it into everything we do and use it as a standard technology.

This method is relatively simple and versatile, making it an attractive tool for researchers worldwide. In addition, teams that combine scanning tunneling microscope and terahertz light in various ways have significantly increased the possibility of discovering more new materials across the materials field.

The team's research results were published in the journal Nature Photonics.