Design Principles for Wurtzite-type Ferroelectrics
•Ferroelectrics (FEs) based on tetrahedral bonding such as wurtzite (Al,Sc)N, (Al,B)N, and (Zn,Mg)O alloys promise performance and semiconductor integration advantages over classic FEs.
•Challenge: Known tetrahedral FEs require large electric fields for polarization reversal (coercive fields).
•Approach: We performed a large-scale computational search to identify candidates for tetrahedral FEs; four compounds emerged as targets for further investigation and potential alloying.
•Materials Design Rules: Our findings highlight the fundamental materials properties—bond ionicity and strength–that affect the magnitude of coercive fields in tetrahedral ferroelectrics and showed that the popular design rule (c/a lattice constant ratio) applies only within a given alloy, not across different compounds