Characterization of LC-tank circuits for mm-wave applications in 90 nm CMOS

In recent years, CMOS millimeter-wave design got significant research interest. In such frequency band, the parasitic elements of passive devices have a large influence on the circuit´s performance which should be carefully considered. In this work, two on-chip spiral inductors have been designed in 90 nm CMOS technology for mm-wave applications. Then based on these self-designed spiral inductors and foundry based MIM capacitors, two different resonant tank circuits have been designed and characterized at 60 GHz and 40 GHz respectively. Good agreements between the measurement and simulation results have been obtained which validate our design process and mm-wave measurements including the utilized on-chip de-embedding technique. The performance of inductors and tanks has been characterized up to 100 GHz which are helpful for the optimization of mm-wave VCO designs.