讲述了一种高Q值的λ/4吸收型超导共面波导谐振器的设计、制备及在低温超导状态下对其传输特性的测量分析。通过磁控溅射工艺在硅基底上沉积一层铌膜,再通过光刻工艺制备出谐振器样品。在100mK的低温状态下,利用矢量网络分析仪测量其传输特性,并研究了温度对传输特性的影响。实验结果表明:该谐振器的Q值可达10^5量级,损耗在-15dB左右;温度升高时,谐振频率增大,传输系数S21,相位φ也随之发生变化。
Design, fabrication and measurement in ultra-low temperature state of high-Q λ/4 absorption-type superconducting coplanar waveguide (CPW) resonator is described. A layer of niobium film is deposited on the silicon substrate via magnetron sputtering technology, and then CPW resonator is made by photolithography. The transmission characteristics of the resona- tor is measured by the Agilent E5071C vector network analyzer (VNA) at 100 mK. The effect of the temperature on the transmission characteristics is studied. The experimental results show that the quality factor of this device is up to the order of 10^5, the loss is about -15 dB ; when the temperature increases, the resonance frequency becomes larger, the transmission coefficient S2, and the phase φ change with it at the same time.