  Trapping ions in Paul traps requires high radio-frequency voltages, which are
generated using resonators. When operating traps in a cryogenic environment, an
in-vacuum resonator showing low loss is crucial to limit the thermal load to
the cryostat. In this study, we present a guide for the design and production
of compact, shielded cryogenic resonators. We produced and characterized three
different types of resonators and furthermore demonstrate efficient impedance
matching of these resonators at cryogenic temperatures.
