Using an improved reactive sputter deposition technique, zirconium dioxide is deposited on cooled and uncooled substrates at low, medium, and high rates of 51.7, 95.4, and 152.4 nm/min, respectively. The films are deposited by sputtering a Zr target in an oxygen–argon plasma. The Zr target remains in the metallic state. The films are characterized by measuring the stoichiometry, refractive index, optical transmission, stress, and crystallinity as a function of deposition rate. Films deposited on (100) N‐type silicon substrates were annealed at temperatures ranging from 200 to 500 °C in steps of 50 °C. X‐ray diffraction patterns show that the ‘‘as‐deposited’’ films contain polycrystalline and amorphous phases of various amounts depending on the deposition rate and substrate temperature. Amorphous components crystallize into the cubic phase as the annealing temperature increases. At deposition rates of 95.4 and 152.4 nm/min, the refractive index and optical transmission (at 820 nm) of the unannealed, as‐deposited films are not affected by the quantity of material in the amorphous state and are also independent of substrate temperature.