Multimodal Characterization of Wide Bandgap Semiconductor Wafers

As the name suggests, wide bandgap semiconductor materials have high energy bandgaps that typically correspond to photon energies in ultraviolet (UV) part of the optical spectrum and higher. Their high bandgaps often mean they are thermally and electrically stable, and so lend themselves for use in critical applications such as power generation and storage as well as new applications such as electric vehicle mobility.

 

At the core of these applications are semiconductor chips made from wafers of wide bandgap semiconductors such as Silicon Carbide (SiC), Gallium Nitride (GaN) etc. For the applications driven by these chips to gain widespread use, the unit cost of the chips must continue to drop - sometimes by orders of magnitudes. And for chip cost to drop the yield for the wafers from which they are derived must increase. That is having more usable chips from a wafer for a given application.

 

There are many factors that affect wafer yield such as uniformity and defectivity amongst others. Currently optical spectroscopies such as Raman and Photoluminescence are some of the techniques of choice in assessing these wafer performance parameters.

 

In this webinar, we show the relevance of applying spectroscopic tools such Raman, Photoluminescence, Time-Resolved Photoluminescence and Cathodoluminescence in characterizing key wafer performance parameters for wide bandgap materials. We also address some of the unique challenges in doing these measurements for wide bandgap semiconductors and how to overcome them.

 

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