Abstract Strong ferroelectric behavior and potential for a wide memory window in wurtzite aluminum scandium nitride shows significant promise for non-volatile memory applications. However, significant DC electrical leakage impedes device applications. We demonstrate growth of polycrystalline wurtzite AlScN thin films using reactive sputtering that exhibit second harmonic generation and polar domains in differential phase contrast STEM despite exhibiting high DC electrical leakage. Electrical characterization indicates weak ferroelectricity consistent with polarization switching although the magnitude is significantly lower than what is expected in this material system. Our results suggest that ferroelectricity and free charge carrier conduction in wurtzite AlScN occur independently. Graphical abstract
Gamachchi et al. (Mon,) studied this question.