A GaNHFETDevice Technology on 3"SiCSubstrates for Wireless Infrastructure Applications

Thisreport presents aGaN HFET technology forwireless infrastructure applications. Usingan optimized process, lowDC-RFdispersion isseenvia pulsed I-Vmeasurements. Atadrainbiasof48V and frequency of2.14GHz,devices with0.3mm gate periphery produce 10-11 W/mm withassociated PAE'sin therangeof62-67%.Devices with12.6mm gatewidths produce asaturated output powerof74W (5.9 W/mm) withanassociated power-added efficiency (PAE)of55%. Undersingle-carrier W-CDMA conditions, an output powerofapproximately 10W and27%associated power- addedefficiency (PAE)isrealized atanACPRof-40dBc. I. INTRODUCTION Thelast fiveyearshaveseenrapid progress in AlGaN/GaN HFETtechnology. Thesimultaneous high electron sheet density andhighbreakdown voltage combined withhighelectron velocity ofGaN-based devices haveenabled order-of-magnitude increases in powerdensities foragiven operating frequency. The higherpowerdensities and subsequently lower capacitance perunitgatewidthafforded bythese devices inturn allow thedesigner tomatchAlGaN/GaN HlFET's overamuchwider bandwidth thanpreviously possible forSiorGaAsbased microwave transistors. In spite ofthese fundamental advantages that GaN-based transistors haveforpoweramplifier applications, ithas only beeninthelast twoyears that GaNonSiCwafer sizes havereached asize that may,atsomepoint, be economically viable forcommercial applications. A numberofreports on48Voperation forGaNonSiC- baseddevices forwireless infrastructure haveshown strong performance fordevices fabricated on2"GaN onSiCwafers (e.g. (1)). This paper demonstrates GaN- on-SiC devices forbasestation application fabricated using Freescale's baseline GaNprocess on3"GaN-on- SiCwafers. Measurements of DC characteristics show