LAUSR

Continuous advancement in nonvolatile and morphotropic beyond-Moore electronic devices requires integration of ferroelectric and semiconductor materials. The emergence of hafnium oxide (HfO2)–based ferroelectrics that are compatible with atomic-layer deposition has opened interesting and promising avenues of research. However, the origins of ferroelectricity and pathways to controlling it in HfO2 are still mysterious. We demonstrate that local helium (He) implantation can activate ferroelectricity in these materials. The possible competing mechanisms, including He ion–induced molar volume changes, vacancy redistribution, vacancy generation, and activation of vacancy mobility, are analyzed. These findings both reveal the origins of ferroelectricity in this system and open pathways for nanoengineered binary ferroelectrics. Description Ion enhanced polarization Hafnium oxide is an exciting material because it has ferroelectric behavior that makes it attractive for various device applications. Kang et al. found that the ferroelectric properties improve by bombarding films of hafnium oxide with a beam of helium ions. The ion bombardment creates oxygen vacancies and strain changes from helium implantation that push more of the polycrystalline samples into the ferroelectric orthorhombic phase. This method may become an important tool for stabilizing the ferroelectric phase for the next generation of electronic devices. —BG Helium ion bombardment of hafnium dioxide thin films improves the ferroelectric properties.