电阻率对硅衬底微波传输特性影响分析

针对传统硅衬底介质损耗大的现象,通过软件电磁仿真手段分析不同电阻率硅衬底上微带线的传输特性,系统研究电阻率变化对硅衬底微波传输特性的影响,并与基于MEMS三维加工的低阻硅衬底进行比较。在30 GHz频率范围内,当硅衬底电阻率从10Ω·cm提升至4 000Ω·cm时,微带线插入损耗从20 dB/cm降低至0.6 dB/cm。电阻率大于100Ω·cm的高阻硅衬底微波传输特性优于带MEMS空腔的10Ω·cm低阻硅衬底。结果表明提升电阻率可有效降低硅衬底微波传输损耗,结合低成本成熟工艺等优点,高阻硅衬底具有广阔的微波集成应用前景。

Effect of resistivity on microwave transmission property of Si-substrate

In consideration of the phenomenon that the dielectric loss of common Si-substrate is high,the microwave trans-mission characteristics of microstrip line on Si-substrate with different resistivity is investigated based on EM simulation software. The effect of resistivity on microwave transmission property of Si-substrate is systematically researched. The Si-substrate is com-pared with the low resistivity Si-substrate fabricated by MEMS 3D machining method. In 30 GHz period,the insertion loss of mi-crostrip line is reduced from 20 dB/cm to 0.6 dB/cm while the resistivity of the Si-substrate is raised from 10 Ω/cm to 4000 Ω/cm The microwave transmission characteristics of the Si-substrate with resistivity higher than 100Ω·cm is better than that of the 10 Ω·cm Si-substrate with a MEMS cavity. The results show that microwave transmission loss of the Si-substrate can be effective-ly reduced by raising resistivity. With advantages including low cost and mature technology,high resistivity Si-substrate will have a wide prospect in microwave integration and application.