Miniaturized Multilayer Inductors onGaAs Three-dimensional

Newlydeveloped multi-layer inductors onGaAs We present miniaturized multilayer inductors, whichwe three-dimensional MMICs arepresented. We tested single-, useinGaAs3D-MMICtechnology todevelop morehighly double-, triple-, andquadruple-layer stacked-type inductors in integrated chips. whatmaybethefirst report oninductors onaGaAsMMIC with three ormorelayers. Theseproposed multilayer inductors can II.INDUCTOR DESIGN produce higher inductance inthesameareaasconventional 2D- MMICs.Theperformance ofthesingle- andmultilayer inductorsThe3D MMIC fabrication process incorporates five wasmeasured onwaferandcalculated byelectromagnetic fieldpolyimide layers andfourwiring metals onthesurface ofthe analysis using thefinite element method. Thoughtheyarethe GaAswafer.Figure 2 showsthemultilayer inductors. The samesize, themultilayer inductors produce 2-11timeshigherspiral pattern still consists ofa2-ptm-thick top-level low-loss inductance thanthesingle-layer inductors. Inaddition, the Auline ofthe3-Dprocess. A 1-ptm-thick TFMSline located degradation ofthemultilayer inductor performances, suchas 2.5ptm underthespiral pattern isusedastheinductor resistance, Q-factor andself-resonant frequency, wasnotseenunderpass. Theopenground plane isformed onthelower- compared withthesingle-layer inductors. Multilayer inductorslevel Aulayer ofthe3-DMMIC process, just overtheGaAs makeitpossible toshrink circuit size frommanyhundreds of MHztothemillimetre wave. active process. IndexTerms-GaAs, multilayer inductors, stacked inductors, TFMSline BroadsideMultilayer Dielectric three-dimensional MMIC technology. coupler inductor layers