Exploring the limits of scanning electron microscopy for the metrology of critical dimensions of photoresist structures in the nanometer range

Evaluation techniques for semiconductor devices are keys for device development with low cost and short period. Especially, dopant and depletion layer distribution in device is critical for electrical property of the device and is needed to be evaluated. Super-higher-order nonlinear dielectric microscopy (SHO-SNDM) is one of the promising techniques for semiconductor device evaluation. We developed method for imaging detailed dopant distribution and depletion layer in semiconductor device using SHO-SNDM. As a demonstration, cross-section of a SiC power semiconductor device was measured by this method and detailed dopant distribution and depletion layer distribution were imaged.