Atomic Layer Deposition of Ta_2O_5/Polyimide Nanolaminates

摘要

Ta_2O_5/polyimide nanolaminates are deposited at 170 8C by atomic layer deposition (ALD). The precursors are tantalum ethoxide and water for Ta_2O_5, and pyromellitic dianhydride (PMDA) and diaminohexane (DAH) for polyimide. The nanolaminates are characterized by X-ray reflection (XRR), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), capacitance and current-voltage measurements, and nanoindentation. The layered structure is confirmed by the XRR data and FESEM images. By controlling the relative thicknesses of the Ta_2O_5 and polyimide layers, the dielectric and mechanical properties of the nanolaminates are tailored over wide ranges. Dielectric properties of the nanolaminates are improved compared to bare Ta_2O_5 and polyimide films. Elasticity of the nanolaminate films increases with the polyimide content.