Synthesis and characterization of methyltriethoxysilane based low permittivity (low-k) polymeric dielectrics

A low-permittivity (low-k) polymeric material has been synthesized using methyltriethoxysilane as base material. The films were reproduceably deposited, by spin-coating on Si wafers with a uniform thickness in the range of 0.3-0.5mum depending on speed. The parameters for spin coating (spin speed and spin time etc.,) have been optimized. The effects of various curing conditions on the structural and dielectric properties have been studied. Fourier Transform Infrared Spectroscopy (FTIR) shows prominent peaks of Si-CH3 stretch and Si-O stretch modes. Test structures on silicon were fabricated to measure the dielectric constant (k) of the material. The values of k were found to be in the range of 2.6-1.2 for annealing temperatures 150degreesC-450degreesC. The dielectric constant decreases as the curing temperature increases.