Thickness Description of Thick GaN Film Stack and Measurement of Al Percentage in AlGaN Alloy with KLA SpectraShape™ 10K

Broadband spectroscopic ellipsometry (BBSE) has been successfully used to characterize and measure layer thicknesses in complex GaN/AIGaN/Ainfilm stacks using the KLA SpectraShape 10K dimensional metrology system. With a parametric oscillator model for the AlxGal-xN alloy dispersion, the dependence of the alloy bandgap from the Aluminum concentration was tracked and compared to reference photoluminescence (PL) data. A correlation table was created using a quadratic relation allowing for immediate measurement of the Al concentration directly on the SpectraShape 10K tool.