Thin-film integrated passive devices (IPD)
Integrated Passive Devices (IPDs) are attracting an increasing interest due to constant needs for lighter, smaller, faster, “smarter”, and more economical and sophisticated mobile devices. IPDs are multiple passive components sharing a substrate and a package, which can be designed as flip-chip mountable or wire bondable components, and are generally fabricated on silicon, silicon-on- insulator (SOI), GaAs, sapphire, or glass substrates using standard wafer fabrication technologies, such as thin film and photolithography processing. A variety of functional blocks, e.g. impedance matching circuits, harmonic filters, couplers and baluns, power combiner/divider, etc. can be realised by IPD technology (see Fig. 1).