Effect of high-temperature annealing on lanthanum aluminate thin films grown by ALD on Si(100)

Amorphous lanthanum aluminate thin films were deposited by atomic layer deposition on Si(1 0 0) using La((i)PrCp)(3), Al(CH(3))(3) and O(3) species. The effects of post-deposition rapid thermal annealing on the physical and electrical properties of the films were investigated. High-temperature annealing at 900 degrees C in N(2) atmosphere leads to the formation of amorphous La-aluminosilicate due to Si diffusion from the substrate. The annealed oxide exhibits a uniform composition through the film thickness, a large band gap of 7.0 +/- 0.1 eV, and relatively high dielectric constant (kappa) Of 18 +/- 1.