Zinc oxide thin films were deposited by atomic layer deposition (ALD). The structural and mechanical properties of the thin films were investigated by x-ray diffraction, transmission electron microscopy, atomic force microscopy, and nanoindentation. Diethyl zinc was used as the chemical precursor for zinc and water vapor was used as the oxidation agent. The samples were deposited at 150 • C and at a pressure of 2.1 × 10 −1 Torr in the ALD reactor. A growth rate of 2 Å per cycle was calculated in the ALD process window. The Nano Indenter XP was used in conjunction with the continuous stiffness method in depth control mode in order to measure and to analyze the mechanical properties of hardness and modulus of ALD ZnO thin film samples. For comparison, we benchmarked the mechanical properties of single crystal bulk ZnO samples against those of our ALD ZnO thin films.

We investigated the structural and mechanical properties of 400 nm and 40 nm thick ALD ZnO thin films. Diethyl zinc was used as the precursor for zinc and water vapor was used as the oxygen source. The samples were deposited at 150 o C and at a pressure of 2.1x10 -1 Torr. A growth rate of 2 Å per cycles was calculated in the ALD process window. The Nanoindenter XP from MTS was used in conjunction with the continuous stiffness measurement (CSM) in depth control mode to analyze the elasto-mechanical properties of ALD ZnO thin films samples. For comparison we benchmarked the mechanical properties of single crystal bulk ZnO samples against our ALD ZnO thin films. We measured the modulus and hardness values of 125±1.6GPa and 5.6±0.09GPa respectively for our single crystal bulk ZnO reference sample.

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