  We demonstrate dispersion engineering of integrated silicon nitride based
ring resonators through conformal coating with hafnium dioxide deposited on top
of the structures via atomic layer deposition (ALD). Both, magnitude and
bandwidth of anomalous dispersion can be significantly increased. All results
are confirmed by high resolution frequency-comb-assisted-diode-laser
spectroscopy and are in very good agreement with the simulated modification of
the mode spectrum.
