论文标题
使用二氧化钒开关的可重构带式过滤器的温度依赖性
Temperature Dependence of Reconfigurable Bandstop Filters Using Vanadium Dioxide Switches
论文作者
论文摘要
在这封信中，我们报告并研究了用二氧化钒（VO2）开关的各种射频参数（RF）的温度依赖性（RF），最高可达55 GHz。在这里，在加热和冷却中分析了Vo2薄膜对滤波器的RF特性的影响，对vo2薄膜对过滤器的RF特性的影响的绝缘体（ITM）和金属到绝缘体过渡（MIT）磁滞。探索了谐振频率和最大插入损失（IL）稳定性以及温度变化的灵敏度。值得注意的是，从25°C使用50°C升高（或从120°C下降低50°C）将导致相对于OFF和共振频率的分数频率偏移小于1％。 VO2薄膜周围的尖锐直流电导率水平的变化对过渡温度的变化转化为对过滤器的共振特性的急剧影响。相反，最大IL水平对DC膜的敏感性不太敏感，在VO2过渡温度周围变化。最后，我们看到在80°C的加热和冷却中的RF参数上方（但接近）VO2的直流过渡温度表现出完全不同的共振频率。 RF结果报告接近VO2薄膜的过渡温度可能会在加热和冷却方面有所不同，因此对VO2可重构RF设备的更深入的了解必须包括在RF范围下低于MIT和ITM的温度下的温度依赖性测量值
In this letter we report and investigate the temperature dependency of various radio frequency parameters (RF) for a fabricated reconfigurable bandstop filter with vanadium dioxide (VO2) switches measured up to 55 GHz. Here the insulator to metal (ITM) and metal to insulator transition (MIT) hysteresis of the VO2 thin film influence on the RF characteristics of the filters is analyzed from 25 °C and 120 °C in heating and cooling. The resonance frequency and maximum insertion loss (IL) stability and sensitivity with temperature variations are explored. It is noticed that increasing the temperature with 50 °C from 25 °C (or decreasing it with 50 °C from 120 °C) will result in a less than 1% fractional frequency shift in respect to the off and on resonance frequencies. The sharp DC conductivity levels variations of the VO2 thin film around the transition temperatures translate into sharp effects on the resonance characteristics of the filters. On the contrary, the maximum IL levels are less sensitive to the DC films sharp conductivity changes around the VO2 transition temperature. Last, we see that the RF parameters in heating and cooling at 80 °C, above (but close to) the DC transition temperatures of VO2 exhibit completely different resonance frequencies. The RF results reported close to the transition temperatures for the VO2 thin films can diverge in heating and cooling, thus of a more insightful understanding of VO2 reconfigurable RF devices has to include temperature dependent measurements at various temperatures below MIT and ITM in the RF ranges too
