Probabilistic design approach for integrated passive devices in RF applications

This paper presents a new approach to designing robust circuits implementing integrated passive devices (IPD) for radio frequency applications fabricated with thin film technology. IMEC´s thin film rf-IPD technology allows defining high-accuracy and high-Q passive components, e.g. transmission lines, inductors, resistors and various types of capacitors, in a cost-effective process. This paper uses a case study based on electrical characterization data for a LC tank based filter using Ta₂O₅ and BCB dielectrics. The effect of the variations in the fabrication process on the performance of the filter and the resulting feedback to the manufacturing of the RF - IPDs is studied. Deterministic approaches are unable to take into account actual variability in design and manufacturing without over-dimensioning the design or assuming a too pessimistic view on the actual characteristics. The probabilistic design approach can be used to align the design with the realistic manufacturing tolerances so that the final design will be always reliable for the given processing variations.