Influence of a thick nitride layer on transmission loss in GaN-on-3C-SiC/low resistivity Si

抄録

We report the effect of a thick nitride layer on transmission loss in GaN-on-3C-SiC/low resistivity Si (LR-Si). Microstrip lines of finite length and width with ground pads were fabricated on three GaN-on-3C-SiC/LR-Si epitaxial structures with varying nitride layer thicknesses of 3.2, 5.3, and 8.0µm. The loss performance of microstrip lines on different substrates was evaluated in the frequency range of 0.1 to 9GHz. The sample with 8.0µm thick nitride layer showed a minimal loss of 0.3dB/mm at 9GHz compared to the other samples. The evaluated data from electromagnetic (EM) simulation also confirmed a decreasing trend of loss with increasing nitride layer thickness. Temperature dependent loss evaluation also verified the above fact.