GaN-on-Si HEMT power devices are projected an enormous growth in the next decade, if the remaining technical challenges in frontend processing can be solved. As a result, the epitaxial layer structures will further increase in complexity. Analogously, wafer uniformity requirements tighten. To keep the frontend processes of these structures in close control, optical metrology is indispensable. By connecting wafer-specific measurements and analysis results from different steps of the frontend process utilizing their individual sensitivities, a full 2D characterization of HEMT device structure epi-wafers can be obtained despite the increasing layer complexity and will become mandatory in the next years.
Johannes Zettler is a product manager at LayTec AG, a Berlin-based company that develops and manufactures optical metrology for the semiconductor industry. Johannes obtained his Ph.D. in experimental physics from the Humboldt University of Berlin in 2015 for his research on the growth of gallium nitride nanowires. Having already worked at LayTec as a working student, he returned to LayTec in 2015 as an R&D project manager. He has led numerous product and technology developments including the EpiX wafer mapping tools before taking over the role of product manager for the EpiX tools. He likes spending time with his two kids, enjoys cycling, hiking and playing football.