Selforganization

Self-organization cannot be regarded as a technological method in the proper sense. In fact, it is a molecular building scheme by which growth-and structure-forming processes in nature also take pace. In this process, individual building blocks such as molecules, atoms, and particles combine to form functioning units. The organization process is regulated by interactions between the individual building blocks (Eickenbusch et al. 2003). A pivotal characteristic of self-organization is that the information for the structural formation is stored in the individual building blocks. The most important role here is played by geometric shapes and charge distributions that permit the building blocks to fit together only in specific ways.

One method for the production of self-organized structures that is already being used in products intended for the marketplace is the formation of self-assembled monolayers.

Self-Assembled Monolayers (SAM): Long-chain organic molecules form densely packed single-layer structures by adsorption on oxidic and metallic surfaces. In this way, ultra thin films can be made with a structure that is pre-determined by the configuration of the substrate surface atoms, which form chemical bonds with the adsorbed molecules (see Fig. 11). These layers are referred to as self-organized monolayers (Jelinski 1999).

If the molecules deposited in the monolayer contain, in addition to the functional group needed for the bond to the substrate, an additional one at the opposite end of the molecule chain, this can be used as a template for the selective deposition of inorganic materials.

Fig. 11. Production of self-organized monolayers42
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