Low-k dielectric aerogel and preparation method therefor

A preparation method for a low-k dielectric organic/inorganic aerogel composite material, comprising:

• mixing step:
• mixing an alkoxysilane compound or a hydrophobically modified alkoxysilane compound with an organic mixed solvent to form a mixed solution;
• hydrolysis step:
• adding an acid catalyst into the mixed solution in order to perform a hydrolysis reaction;
• condensation step:
• adding a basic catalyst into the mixed solution after the hydrolysis reaction in order to perform a condensation reaction, and also adding a surfactant during the condensation reaction process;
• aging step:
• performing aging of an aerogel board formed via the condensation step in order to promote an aerogel structure to condense further and to achieve a aerogel board structure;
• drying step:
• after gelatinization in the condensation step and stabilization of the aerogel board structure, performing drying under an environment of constant pressure in order to obtain a low-k dielectric silicon-based aerogel board having a uniform structure;
• impregnating polymer solution step:
• impregnating the low-k dielectric silicon-based aerogel board into a dilute polymer solution in order to allow polymer chains to infiltrate into an internal of the low-k dielectric silicon-based aerogel board uniformly, thereby forming a wet polymer/silicon-based composite material, wherein the polymer chains are configured to be covered onto a network skeleton structure of the low-k dielectric silicon-based aerogel board;
• phase separation and drying step:
• placing the wet polymer/silicon-based composite material in order to allow a solvent in the dilute polymer solution to vaporize, thereby performing a liquid-solid phase separation on polymers inside the wet polymer/silicon-based composite material in order to further allow the polymer chains to cover onto the network skeleton structure of the low-k dielectric silicon-based aerogel board and to be dried gradually, and forming a polymer/silicon-based composite material after drying;
• and
• cross-linking and curing step:
• placing the polymer/silicon-based composite material after drying in order to allow the polymer chains covered onto the network skeleton structure of the low-k dielectric silicon-based aerogel board to perform a cross-linking reaction, and chemical reaction bonding occurred among the polymer chains and occurred between the polymer chains and silicon-based aerogel molecules of the low-k dielectric silicon-based aerogel board during the cross-linking reaction, thereby obtaining a porous and low-k dielectric polymer/silicon-based aerogel composite material after the cross-linking reaction.