Microwave dielectric relaxation of silicon crystals

The dielectric properties of Si crystals are studied in the frequency range of 0.5–13.5 GHz using convenient non-destructive measurement of a material permittivity system which consists of an open-ended co-axial line and a microwave vector network analyser. It is found that there exists a dielectric relaxation at microwave frequency in Czochralski grown silicon crystals (CZ-Si). The dielectric constant of CZ-Si varies from about 70.0 to 11.7 within the frequency region studied. In contrast to CZ-Si, floating zone grown silicon shows no such relaxation phenomenon. The correlation between the impurity properties and the dielectric relaxation in silicon crystals is discussed.