Estimation of the dielectric properties of low-k materials using optical spectroscopy

The dielectric function spectra of low dielectric constant (low-k) material s have been determined using spectroscopic ellipsometry, near-normal incide nce spectroscopic reflectometry, and Fourier transform infrared transmissio n spectrometry over a wide spectral range from 0.03 to 5.4 eV (230 nm to 40 .5 mum wavelength region). The electronic and ionic contributions to the ov erall static dielectric constant were determined for representative materia ls used in the semiconductor industry for interlayer dielectrics: (1) FLARE -organic spin-on polymer, (2) HOSP-spin-on hybrid organic-siloxane polymer from the Honeywell Electronic Materials Company, and (3) SiLK-organic diele ctric resin from the Dow Chemical Company. The main contributions to the st atic dielectric constant of the low-k materials studied were found to be th e electronic and ionic absorptions. (C) 2001 American Institute of Physics.