A low-pressure chemical vapor deposition (CVD) reactor was modified to produce a continuous compositional spread of titanium, tin, and hafnium dioxides on a single Si(100) wafer. The corresponding anhydrous metal nitrates, Ti(NO3)4, Sn(NO3)4, and Hf(NO3)4, were used as single-source precursors to the component oxides. The compositions were mapped using X-ray photoelectron spectroscopy and Rutherford backscattering spectrometry. On a single wafer an array of 100 μm x 100 μm capacitors was used to map the effective dielectric constant (Keff) of the films. For compositional spreads grown at 400 and 450 °C Keff reached a maximum value in regions with the highest concentrations of TiO2. The formation of the orthorhombic α-PbO2 phase for a composition near Hf0.75Sn0.25O2 was also observed in the 450 °C compositional spread.