Fully Integrated Low Phase-Noise VCOs: From Special Processing to Standard CMOS

An overview is given on the several options for and problems associated with creating high-quality integrated inductors for VCOs. Special processing techniques are reported that can enhance the performance of a normal planar inductor coil. Bonding Wire inductors are presented as an alternative, that allows state-of-the-art phase noise performance at no extra cost. Finally, it is shown that by thorough analysis of standard planar inductors with finite-element simulations, performances can be achieved that are even better than structures requiring extra processing cost. This is done despite a low-ohmic substrate with only two metal layers.