27012021 1611755154

The downscaling of device dimensions in electronic integrated circuits (ICs) is requiring the integration of new materials, while it is simultaneously leading to challenges with respect to pattern alignment during fabrication. Together, these developments demand cutting-edge methods to grow ultrathin films in a controllable and preferably bottom-up manner. A technology which is playing a significant role in these developments is atomic layer deposition (ALD). This deposition technique relies on the cyclic dosing of a precursor (“A”) and a co-reactant (“B”) chemical. It allows for the growth of ultrathin films with a high uniformity on large-area substrates, and excellent conformality on 3D structures, while having a very precise thickness control. In this dissertation, advanced cycles beyond traditional AB-type cycles and ALD processes employing novel co-reactants were investigated for growth of aluminum fluoride (AlF3), Co and Ru. Examples of advanced ALD cycles are ABC-type cycles and supercycles comprised of two ALD cycles. As demonstrated in this work, such advanced ALD processes can for instance be employed for area-selective ALD, which enables bottom-up fabrication, thereby reducing the number of required lithography and etch steps. In addition, it is shown that novel co-reactants can enable deposition of new materials by ALD, as well as extension of process parameters. Ultimately, the obtained insights help to extend the ALD toolbox, in terms of the number of materials that can be deposited by ALD, as well as the possible applications of ALD.

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