Superconducting Bandpass Fitter Using Hairpin-type Microstrip Line with Narrow Bandwidth Centered at 14 GHz

14 GHz 헤어핀형 초전도 대역통과 필터

In order to enhance satellite communication system performance, filters are required with the characteristics of sharp skirt, low insertion loss, and high power handling capability. But the performance of microwave passive filters is significantly declined by the conduction losses, especially in case of planar structures using film conductors. By using high temperature superconducting(HTS) film material as the conductor, higher performance could be expected. We have designed and developed narrow bandpass filters using haripin-type superconducting microstrip line for satellite communication. High quality superconducting YBCO thin films have been grown on MgO substrates by pulsed laser deposition(PLD) The deposited YBCO films were patterned by conventional wet-etching process. The transition temperatures of these films had shown 86 - 89 K. The film thicknesses were about 500 nm. Experimental results are presented for the insertion loss and return loss of the filter at 60 K.