ULTRALOW ABSORPTION IN SILICON CARBIDE IN THEMILLIMETER-WAVE RANGE
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2016-11-01 |
| Authors | E. E. Chigryai, Š.Š. ŠŠ°ŃŠøŠ½, R. N. Denisyuk, D. S. Kalenov, I. P. Nikitin |
Abstract
Section titled āAbstractāDielectric properties of high-purity semi-insulating single-crystal 6H silicon carbide are investigated in the millimeter-wave (MM) range. A method and a setup are developed for measuring ultralow dielectric loss in the long-wavelength part of the millimeter-wave band at frequencies below 80 GHz in samples with relatively small transverse size (~20 mm) and arbitrary thickness (~1 mm or less). The method and the setup are based on a semisymmetric open resonator with spherical mirror with radius of curvature of 40 mm. The value of loss tangent measured at 69.4 GHz and room temperature is tand ~ 6Ć10-5, which is the lowest value ever observed in this material. This value is significantly lower than that observed in well-known low-loss materials such as single-crystal sapphire and quartz but exceeds the loss value in the best samples of CVD diamond. However, SiC has lower production cost compared to the latter. The loss mechanisms in silicon carbide are revealed. At low frequencies <20 GHz, the loss is due to absorption by free charge carriers. In the region 60-400 GHz, the loss can be attributed to the intrinsic lattice loss due to two-phonon absorption processes.
Tech Support
Section titled āTech SupportāOriginal Source
Section titled āOriginal Sourceā- DOI: None