We report on the implementation of vacuum parallel-plate capacitor MKIDs for astronomical applications. MKIDs features an intrinsic excess noise probably due to the two-level systems (TLS) generated at metal/dielectric interface, particularly when dielectrics are amorphous, as well as in the bulk substrate. To attempt to reduce TLS, several groups are intensively investigating the use of monocrystalline silicon , a-SiNx:H  or SiNx dielectrics which can feature low amount of defects. However, these would not guarantee a substantial gain in performance. The ideal solution is likely the use of capacitors without dielectrics as TLS would be predominant in this part of resonator. In this paper, we will present the performance of first vacuum parallel plate capacitor MKIDs implemented using a straightforward fabrication process that allowed to achieve resonators with internal quality factors of 2-4×10^5.
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|Less than 5 years of experience since completion of Ph.D||N|
|Student (Ph.D., M.Sc. or B.Sc.)||N|