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DOE OSTI · 1828105

Ultrafast Electron Microscopy for Spatial-Temporal Mapping of Charge Carriers

Nakakura, Craig Y.·Ellis, Scott R.·Celio, Kim·Smoll, Eric·Chandler, David W.·Michael, Joseph Richard
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Abstract

This LDRD supported efforts to significantly advance the scanning ultrafast electron microscope (SUEM) for spatial-temporal mapping of charge carrier dynamics in semiconductor materials and microelectronic devices. Sandia's SUEM capability in Livermore, CA, was built and demonstrated with previous LDRD funding; however, the stability and usability of the tool limited the throughput for analyzing samples. A new laser alignment strategy improved the stability of the SUEM, and the design and characterization of a new micro-channel plate (MCP)- based detector improved the signal-to-noise of the SUEM signal detection. These enhancements to the SUEM system improved throughput by over two orders of magnitude (before, a single time series of SUEM measurements would take several days to several weeks to acquire; now, the same measurements can be completed in~90 minutes in an automated fashion). The SUEM system can now be routinely used as an analytical instrument and will be a central part of several multi-year projects starting in FY22.

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Nakakura, Craig Y., Ellis, Scott R., Celio, Kim, Smoll, Eric, Chandler, David W., Michael, Joseph Richard. 2021-09-01. Ultrafast Electron Microscopy for Spatial-Temporal Mapping of Charge Carriers. https://doi.org/10.2172/1828105

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