The deposition of Al2O3 thin films by atomic layer epitaxy was investigated using Al(CH3)(2)Cl as a new aluminum precursor. All the films grown in the temperature range of 125-500 degrees C were amorphous as examined by x-ray diffraction analysis. The residual contents of carbon, chlorine, and hydrogen in the film deposited at 200 degrees C were 0.2, 2.1, and 12 at. %, respectively, and diminished rapidly with increasing growth temperature. The refractive index of the films increased with deposition temperature, stabilizing at the highest value of 1.68 above 300 degrees C. The permittivity of the films increased from 7.3 to 8.7 with increasing growth temperature from 200 to 500 degrees C. The leakage current density was lowest in the him deposited at 200 degrees C and increased markedly at higher deposition temperatures.