Used as a high-k dielectric material in semiconductor devices, especially in advanced transistor gate stacks to reduce leakage current. Enables scaling of integrated circuits in microprocessors and memory chips. Also applied in optical coatings due to its high refractive index and durability, suitable for lenses, lasers, and anti-reflective coatings. Investigated for use in nuclear reactors as a neutron absorber due to hafnium’s high neutron capture cross-section. Employed in wear-resistant and thermal barrier coatings in aerospace and cutting tools.