Exploring the underlying mechanisms of ferroelectric behavior in metal-doped aluminum nitride: an in-depth review

This review explores the complex interplay between metal doping and the polarization-switching dynamics of wurtzite AlN thin films. We analyze how variations in dopant type, concentration, and crystal structure influence the ferroelectric characteristics of AlN. Particular emphasis is placed on Sc-doped AlN, recognized as a strong candidate for advancing next-generation ferroelectric applications. We investigate the mechanisms underlying polarization switching, addressing the significance of local chemical interactions, structural alterations, and domain wall dynamics. Furthermore, a comparative analysis of primary synthesis techniques—magnetron sputtering, molecular beam epitaxy (MBE), atomic layer deposition (ALD), and pulsed laser deposition (PLD)—is presented, outlining their respective advantages and challenges for producing high-quality ferroelectric films. By elucidating the fundamental principles that govern ferroelectricity in doped AlN, we aim to offer valuable perspectives for the design and optimization of advanced ferroelectric devices, enhancing both performance metrics and energy efficiency.