微加工工艺误差对THz折叠波导行波管性能影响

Effect of microfabrication process on Terahertz folded waveguide TWT

在太赫兹频段,折叠波导慢波结构主要采用微细加工技术完成。讨论了目前折叠波导慢波结构主要的微加工工艺,分析了主要工艺误差包括波导深度、侧壁垂直度对0.41 THz折叠波导慢波结构高频特性的影响。通过分析比较,a值对折叠波导行波管性能影响很大,需要在工艺中精确控制。在侧壁垂直度为89°范围以内,侧壁垂直度的变化对折叠波导行波管性能影响不大。通过仿真分析,确定了工艺中必须控制加工精确度的工艺步骤,这对0.41 THz折叠波导行波管的研制有非常重要的意义。

In THz range, most of the folded waveguide slow-wave structures are fabricated by microfabrication processes. The principal microfabrication processes for fold waveguide structure nowadays are discussed. The influence of microfabrication process errors including the depth a and sidewall profile on the high frequency characteristics of 0.41 THz folded waveguide slow-wave structures are analyzed. Through the analysis, the depth a shows great influence on the performance of folded waveguide Travelling Wave Tubes(TWTs), therefore, it should be controlled accurately in the process. The sidewall profile has little effect on the performance of folded waveguide TWTs when the angle is above 89°. The key processes are determined by simulation, which is helpful for developing THz folded waveguide TWTs.