We describe the deposition of amorphous Zr-Sn-Ti-O (aZTT) dielectric thin films using conventional on-axis reactive sputtering. Thin films of composition Zr 0.2Sn 0.2Ti 0.6O 2 have excellent dielectric properties: 40-50-nm thick films with a dielectric constant of 50-70 were obtained, depending on the processing conditions, yielding a specific capacitance of 9-17 fF/μm 2. Breakdown fields were measured to be 3-5 MV/cm, yielding a figure of merit εε 0E br = 15-30 μC/cm 2, up to eightfold higher than conventional deposited SiO 2. Leakage currents, measured at 1.0 MV/cm, were in the range 10 -9-10 -7 A/cm 2. This material appears well-suited for use in Si-IC device technology, for example as storage capacitors in DRAM.