Molecular-Controlled Fracture and Release of Templated Nanoporous Organosilicate Thin Films

Molecular interactions between templating porogen particles and the underlying substrate can be exploited to create a controlled release mechanism while maintaining the bulk properties of the matrix material. Furthermore, these interactions can be reversed by priming the substrate with a hydrophobic layer to produce a strong interface with a nanoporous layer

Homogeneous Surface Oxidation of Organosilicates by Controlled Combustion of Adsorbed Fuels: A Facile Method for Low-Temperature Processing

We have developed a method for the oxidation of organosilicate materials at temperatures considerably lower than those typically required for uncatalyzed oxidation. The process utilizes a combustible fuel delivered to the surface in an oxidizing environment to locally oxidize materials with carbon–silicon bonds. It also provides a level of control that cannot be achieved through standard high-energy top-to-bottom oxidative procedures such as UV–ozone and O₂ plasmas. While the latter processes attack the outer interface, local oxidation can be achieved using our process by manipulating the distribution of the combustible fuel. We use this technique to generate oxidized porous organosilicate films with either a sharp oxidation front or uniform oxidation where the relative carbon content can be controlled through the film thickness depending on processing conditions. Further, we show that this process can also be used to seal bulk interconnected microporosity in films (<1 nm) without substantially changing the refractive index of the material. For both the nominally dense and porous films, the surface oxidation is accompanied by an increase in the Young’s modulus and the oxidized films can be readily functionalized using standard silane chemistry to provide a variety of chemical functionalities