We have investigated the correlation between the microwave loss and patterning method for
coplanar waveguide titanium nitride resonators fabricated on silicon wafers. Three different
methods were investigated: fluorine-and chlorine-based reactive ion etches and an argon-
ion mill. At high microwave probe powers, the reactive etched resonators showed low
internal loss, whereas the ion-milled samples showed dramatically higher loss. At single-
photon powers, we found that the fluorine-etched resonators exhibited substantially lower …