Fully-integrated voltage controlled oscillator in low-cost HCBT technology

Design of cross-coupled voltage controlled oscillator in low-cost HCBT technology is presented. Beside the low-complexity front-end devices, only 2 metal layers are used and the passives are implemented in the available on-chip structures. Varactors are fabricated as pn-junctions by using the ion implantation from the technology. Symmetric inductors are fabricated by using the topmost metal layer. Since only 2 aluminum metal layers are available, small thickness of the aluminum layer and proximity of the silicon substrate limit the inductor quality factor. Varactor and inductor models for circuit simulations are developed by using the device and electromagnetic simulations, respectively, and are compared to measured characteristics of fabricated devices.