On Miniaturizing On-Chip Microstrip Inductors Using Embedded Radiating Dipoles

As RF mixed-signal and patch-antenna-equipped SOC devices are becoming the dominant products worldwide, concerns over the large real-estate consumption by the spiral inductors (including those for microstrip antennas and impedance-matching inductances), as well as their generally Q-low (quality factor) performance, are now being discussed more than ever. Liao et al. have recently addressed the Q-low issue via using location-selective proton beam bombardment, whereby Q-improvements of 100%–300% were evidenced. That success, nevertheless, is at times tarnished by some undesirable features, that is, the explosive rises of inductances near certain frequencies, which practically cut short the Q-enhancement and were identified to be due to resonant interactions between the inductor-propagating EM wave and the proton-caused defect dipoles. In this paper, however, the authors attempt to turn this resonance-caused undesirability to favor by proposing a new way to greatly shrink down the needed inductor size through dipoles engineering.