Previous reply is correct.

To give a feeling: micro-ribg resonators are anywhere between 10 to 40 micrometer in diameter. You also need a bunch of other waveguides. The process in the paper uses silicon waveguides, with 400nm width if I'm not wrong. So any optical feature unfortunately isn't going down as much as CMOS technology.

Fun fact: the photolithography has the same limitations. They use all kinds of tricks (different optical affects to shrink the features) but fundamentally limited by the wavelength used. This is why we are seeing a push to a lower and lower wavelengths by ASML. That + multiple patterning helps to scale CMOS down.