The miniaturization of conventional ring resonators is demonstrated by forcing a voltage minimum at one end of the resonator. In addition, the resonator is loaded with a capacitance to achieve further miniaturization and reducing its sensitivity to substrate thickness tolerance. The final resonator is 73% smaller than a conventional ring resonator and has a tenfold decrease in sensitivity to substrate thickness variations. Using this resonator a 4-pole quasi-elliptic filter is fabricated showing good agreement between simulation and experimental results.