K.A. Vorotilov - Dr.Sc. (Eng.), Professor, Director, REC «Technological Center», Moscow Technological University. Е-mail: vorotilov@mirea.ru A.V. Kornyukhin - Post-graduate Student, Department of Nanoelectronics, Moscow Technological University. Е-mail: d_seregin@mirea.ru S.A. Kurdyukov - Post-graduate Student, Department of Nanoelectronics, Moscow Technological University. Е-mail: d_seregin@mirea.ru D.S. Seregin - Ph.D. (Eng.), Head of Department, REC «Technological Center», Moscow Technological University. Е-mail: d_seregin@mirea.ru M.V. Starilov - Post-graduate Student, Department of Nanoelectronics, Moscow Technological University. Е-mail: d_seregin@mirea.ru

Preparation of sol-gel nanoporous methyl-modified silica films is discussed. The films with the thickness from 60 to 500 nm are formed on silicon substrates by the spin-on technique. Template method with polyethylene glycol as a porogen is used for film nanoporous structure formation. Polyethylene glycol is added in the film-forming solution; it undergoes destruction during a film heat treatment. As a result pores with size from 60 to 700 nm are formed in the film. The pore size and the effective permittivity values of methyl-modified silica films are strongly depend on the polyethylene glycol concentration in the film-forming solution. The relative porosity of the film reaches 30 % after the thermal destruction of the polyethylene glycol molecules with molecular weight from 200 to 600 g/mol. The pore size decreases from 700 to 60 nm with increasing hydrochloric acid content in the film-forming solutions with 30 wt. % PEG 400 due to hydrolysis acceleration. An increase in annealing temperature from 250 °C to 400 °C leads to a decrease of the effective dielectric constant value up to 2.4-2.6.

 

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